Chapter XXIV: Part 24

The bronchi contain morbid secretions in the form of clear viscid mucus in the early stage, while later they are filled with creamy pus. In some cases there are also found small subpleural collections of more or less inspissated yellowish secretion contained in dilated alveoli or in small globular dilatations of terminal bronchioles. The most plausible explanation of their nature is, as suggested by Fauvel, that they are caused by the suction of particles of bronchial secretion into the alveoli in the forcible inspiratory effects which follow paroxysms of cough, and especially such paroxysms as occur when whooping cough is complicated with catarrhal pneumonia.

The lung-tissue itself exhibits, associated in varying degrees, congestion, oedema, emphysema, collapse, and pneumonic consolidation. The patches of simple collapse are to be easily recognized by their familiar appearance, being depressed below the surrounding tissue, bluish in color, non-crepitant and solid to the touch, and on section smooth, airless, firm, and not friable. They sink in water. As already stated, they can, when recent, be readily inflated, and thus restored to their normal condition. Such patches are most common at the postero-inferior parts of the lungs. They are mostly pyramidal in shape, and vary in size from a few lines to one or two inches in diameter, though in severe cases an entire lobe, or even an entire lung, may pass into this state of collapse. On the other hand, the areas of pneumonic consolidation appear as slightly prominent nodules, varying in size from that of a pea to that of a hazelnut, which may be distinctly felt with the finger, if occurring in the midst of a collapsed patch, by their elevation above the surrounding depressed tissue. They are usually scattered throughout both lungs, often with some symmetry of disposition, especially in the postero-inferior portions. The surrounding zone of tissue is more or less congested and oedematous, and when the nodules are closely adjacent they may become confluent, so that large portions of a lobe or an entire lobe may become infiltrated. Vigorous inflation will usually show in such cases, however, that the consolidation is not uniform or complete. Section of the lung will show that the most varied stages of the inflammatory process are represented in the different nodules; and this is a highly characteristic feature of the disease. The recent nodules are brownish-red or grayish-red, faintly granular, smooth, friable, and yield on scraping a small quantity of thick reddish secretion. Later they become reddish-gray and yellowish-gray in color, yield a thick, airless, milky substance, and finally grow more firm and dry: the inflammatory product undergoes fatty degeneration, is gradually removed by absorption or by expectoration, and the affected area of lung-tissue is slowly restored to its normal state. This is the course in favorable cases, while in those which run into a chronic form or which terminate fatally at an early period the lesions undergo various modifications. In some instances the inflammatory product undergoes more acute degeneration, with destruction of the pulmonary tissue in the affected area, and the subsequent formation of abscesses, which are not to be confounded with the minute aspiration-abscesses above described. I have notes of autopsies in which the lungs have presented every stage of the process of catarrhal pneumonia, from the nodules of incomplete consolidation to {357} circumscribed abscesses. In other cases the thickening of the walls of the alveoli and of the bronchi, together with dilatation of the tubes, has become marked, and the interstitial changes in the zones of peribronchitic pneumonia extend and induce a slow process of fibroid thickening which results in that form of chronic pneumonia which has been called cirrhosis of the lung and fibroid phthisis. In still other cases the morbid products in the alveoli, with or without an antecedent process of suppuration, undergo caseation; and the presence of the degenerate cheesy foci, associated with alveolar and peribronchial thickening, may lead to catarrhal phthisis with or without true tuberculous formations.

The microscopic examination of the pneumonic nodules shows that the essential condition consists in a morbid accumulation within the alveoli, together with changes in the walls of the vesicles, which become infiltrated with cells in the same way as the bronchial walls. These changes become more marked after the disease has lasted some time. The epithelium lining the alveolar walls is the seat of cloudy swelling, becomes less closely attached, and undergoes proliferation, with the formation of large epithelial elements. The morbid product filling the alveoli is composed in varying proportions of these latter elements, of the richly cellular bronchial secretion which has been sucked in from the bronchioles, of leucocytes, and much more rarely of red blood-corpuscles which have escaped from the pulmonary capillaries, and finally of fibrillated exudation. In contrasting these minute appearances of catarrhal pneumonia with those of the croupous form it is to be noted that in the former the fibrinous element is not constant, or is at most scanty, and that the results of diapedesis, leucocytes, and especially red corpuscles, are much less prominent. At a later period of the process fatty infiltration and degeneration of the alveolar contents usually occur, which is the most favorable change, since it disposes toward evacuation with restitution of the lung to its normal state; but at times a larger proportion of pyoid cells appears, and the alveolar walls become involved and break down, so that small abscesses are formed, or, again, the contents may become inspissated and caseous, associated with nuclear growth in the walls of alveoli and bronchioles.

An account has thus been given of the lesions in fully-developed and disseminated catarrhal pneumonia; but I would again ask attention to the existence of a mild and circumscribed form of the disease, which rarely if ever causes death of itself. In these mild attacks, which occur frequently in adults, the part affected may be the base of the lung, but more commonly it is the root, the apex, or the lower anterior portion of the upper lobe. The anatomical condition is probably one of congestion, with extension of catarrhal inflammation into the alveoli without any preceding collapse, and with a varying degree of implication of the walls of the vesicles and of epithelial accumulation in the alveoli, though the process may not always go on to the production of fully-formed pneumonic nodules, such as above described. Yet it seems to me not only illogical, but eminently unsafe, to regard such cases otherwise than as catarrhal pneumonia, since while under proper treatment and in fairly healthy constitutions they uniformly terminate in resolution, on the other hand, they will, if neglected or if occurring in highly-vulnerable constitutions, run into a subacute form, with more extensive implication of the alveolar walls and peribronchial tissue, and will induce catarrhal phthisis. Allusion will be made again to these cases when speaking of the symptoms and diagnosis of catarrhal pneumonia.

In addition to the pulmonary lesions, the bronchial glands are, with rare exceptions, swollen and congested. In cases of longer standing foci of suppuration have been occasionally noted in them (Steiner), though cheesy nodules are more common. Acute miliary tuberculosis is a comparatively frequent complication. Oedema and congestion of the brain and meninges occur {358} frequently, but are to be regarded as secondary lesions without special significance. It is probable, however, that more numerous examinations, in cases where death has been preceded by grave cerebral symptoms, would reveal the occasional occurrence of circumscribed areas of meningitis, with or without miliary tubercles. The liver is congested in acute cases, while in older ones there is apt to be fatty degeneration, which we have seen occur in irregularly distributed patches, imparting a peculiar mottled appearance to the organ. The kidneys also may be congested, but serious changes in the epithelium are rarely met with. Vastly more common are the lesions of catarrhal inflammation of the mucous membrane of the stomach and intestine. While in acute cases they may be superficial and slight, in those which have run a longer course Peyer's patches are prominent, and the solitary glands are enlarged, and not rarely oval ulcerations exist which may coalesce, so that I have seen quite extensive destruction of the mucous membrane of the colon simulating the effects of dysentery.

SYMPTOMS.--Before entering on a detailed description of the symptoms of catarrhal pneumonia it must be premised that this disease presents a far greater range in its degrees of severity than does croupous pneumonia. In this latter disease, although clinical evidence shows that its extent and course are less uniform than is often assumed, there is a remarkable uniformity in the stages through which the inflammatory exudation passes; but in catarrhal pneumonia, as in all forms of catarrhal disease, it is a marked characteristic that the process varies almost infinitely in different cases, both in the location, the extent, and the degree of development of the lesions. It is difficult to avoid the conclusion that a corresponding variety is presented by the symptoms, and that a complete clinical picture of catarrhal pneumonia must include cases of very mild character and of short duration, as well as those of a more severe and fully-developed type. I propose, therefore, to describe a mild form, an acute form of the ordinary well-developed disease, and also a subacute and chronic form.

The mild form is undoubtedly often overlooked, the attack being regarded merely as a feverish cold or as an ordinary bronchitis. Yet certain peculiarities in the symptoms, the course, and the tendencies of the cases I refer to serve to distinguish them, and enable them to be recognized as of more serious nature. More commonly the attacks occur in young adults whose systems are abnormally sensitive either from original weakness or in consequence of overwork, previous sickness, or the action of other depressing and exhausting causes. After some imprudent exposure there is a slight rigor, followed by headache, flushed, feverish feeling, soreness in the chest, aching in the limbs, and tight, dry, painful cough. A careful examination soon after the onset would reveal the familiar signs of a bronchial catarrh, though even now there might be noted a tendency for the affection to be less diffused than is usual in ordinary bronchitis.

If the patient is not prudent and solicitous about his health, no physician is summoned at once, and not rarely in the course of forty-eight or seventy-two hours the general symptoms have subsided so considerably that the patient feels able to move about, and may be led by pressure of business claims to resume his occupation. He finds himself so weak, however, and the cough is so much aggravated, that medical advice is sought. Distinct fever of remittent type is found, the morning temperature not exceeding 100° or 100½°, while in the evening it rises to 102° or 103°. There is a tendency to perspiration, especially on exertion, while exposure to a cool wind or draught causes a chilly feeling; exertion soon fatigues; sleep is restless; appetite is impaired; the tongue coated; the bowels irregular; and the urine high-colored. Cough is troublesome and somewhat painful, and the chest feels sore and weak. Physical examination will reveal, in the first place, bronchitic {359} râles, dry and moist (sonorous, sibilant, and mucous), on both sides of the chest, though not rarely much more markedly on one side than on the other, or even limited to a portion of one side.

In addition to this, careful auscultation, especially if conducted not only during ordinary respiration, but during the strong inspirations which follow cough, will detect in certain localities subcrepitant râles, associated with feeble respiratory murmur and slightly prolonged and blowing expiration. The percussion resonance or the vocal fremitus or resonance may be only slightly impaired. These signs, which are connected with an extension of catarrhal inflammation into the alveoli and the consequent partial occlusion of certain lobules, may be met with in the subclavicular spaces, at the lower anterior margin of the upper lobes, at the roots of the lungs, or elsewhere. If the patient be confined to bed and suitable treatment be employed, the local and general symptoms will pass away in five to ten days. The cough grows looser, and the sputa, which were at first very scanty and mucoid, grow muco-purulent, and then diminish in amount. There follows a greater degree of anæmia and of weakness than would have been expected from what is apparently so slight an ailment, and especially there remains a marked sensitiveness of the throat and chest, so that after any slight recurrence of catarrh there may be a temporary return of râles at the affected spot, until gradually the general health and the healthy tone of the lungs are restored. But if, on the other hand, the patient persists in keeping about and exposing himself, the febrile process of remittent type will be prolonged, and though the disturbance of general health will gradually subside, repeated renewals of catarrhal irritation will occur, and the local disease will become more deeply seated, will be attended with increased infiltration of the lobules, and if the reaction of the system be greatly depressed will end by becoming chronic. According to my observation, it is in this way--and this fact confers its great importance upon the mild circumscribed form of catarrhal pneumonia now under discussion--that very many cases of pulmonary phthisis begin; and according to the power of resistance of the tissues, and to the tendency of the system to become infected by the products of unhealthy inflammation will be the disposition for the disease to assume this unfavorable development. It is true that the precise anatomical conditions present in the early stages of such cases cannot be demonstrated, since death rarely if ever occurs at that period; but it seems difficult to regard them as differing from those found in partially developed patches of consolidation in more severe and typical cases of catarrhal pneumonia. The constitutional symptoms, the local signs, and the course and results of the affection all indicate that it is not an ordinary bronchial catarrh, but that it is properly to be regarded as a mild type of catarrhal pneumonia. Without pretending to describe minutely all the clinical features of these interesting cases, it may suffice to have called attention to their frequent occurrence and great actual importance, and to the fact that owing to the indifference of the patient or to the hasty examination of the physician their true nature is often overlooked and the disease is allowed to pass far beyond its original character of a local catarrhal trouble.

Acute catarrhal pneumonia in its fully-developed form occurs most commonly in children, especially as a complication of measles or in the course of capillary bronchitis. It is evident, therefore, that the passage from the stage of severe bronchial catarrh to that of alveolar inflammation may be barely perceptible at first. This is especially true because in such cases the development of the pneumonia is usually preceded by a considerable amount of pulmonary collapse. The child is already suffering with fever, rapid shallow breathing accompanied with movements of the nostrils and possibly with inspiratory retraction of the thorax, and with frequent painful cough. No rigor, as a rule, occurs to mark the inception of the pneumonic complication. {360} The fever, however, nearly always rises rapidly, and from 102° or 103°, which has been the maximum during the preceding catarrh, it quickly reaches 104° or 105°, or even higher. It will be promptly noticed also that the respirations become even more accelerated, shallow, and imperfect; in some cases they reach 100 in the minute. The alæ nasi play violently; the elevation movement of the thorax is marked, while expansion is but slight; there is retraction of the base of the chest during inspiration, which is short and quick, while expiration is prolonged and labored. Severe suffocative paroxysms occur from time to time. The cough is frequent and painful, so that adults complain severely of it, while in children it causes moaning or crying. Later, when the nervous symptoms grow more prominent, the cough grows much less frequent and severe, or even ceases. Sputa are rarely raised by children unless with the act of vomiting; they are tenacious, but not rusty colored, though they may be slightly streaked with blood. The pulse soon grows very rapid, 160, 180, or even 200 in young children, and loses force and volume. The appetite is lost, but thirst is extreme. The tongue becomes brown and parched from deficient secretion and from mouth-breathing. Diarrhoea is not uncommon, owing to the frequent presence of intestinal catarrh as a complication. The urine occasionally contains a small amount of albumen; and it is stated (Bednär) that the chlorides persist. The nervous symptoms are prominent. As the dyspnoea increases there is extreme restlessness, the child tossing about incessantly, with slight delirium. Soon the flush on the face yields to a distinct cyanotic appearance, with coolness of the extremities. The restlessness subsides, and there is a tendency to stupor, alternating with spells of active and restless delirium, and finally deepening into coma, at times with rolling of the head, so that there may be a close resemblance to the later stage of tuberculous meningitis.

During the development of these symptoms the physical signs are for the most part unsatisfactory and require great care to determine and to interpret them. As already intimated, inspection shows inspiratory retraction of the base of the chest, increased movement of elevation, with defective expansion. Percussion does not usually give definite results, owing to the fact that the lesions may be symmetrical in the two lungs, and because the pneumonic process is complicated to a very variable extent with the results of pulmonary collapse. In children especially the most gentle and careful percussion is requisite to detect and map out the affected areas. Some assistance may be rendered by the fact that the dulness dependent on collapse is often found in the form of symmetrical elongated areas in either intervertebral groove. The results of palpation are even less satisfactory than those of percussion. If the patches of consolidation are not extensive and are scattered, no change will be detected; and it is only when superficial areas of considerable extent are consolidated that distinct increase of vocal fremitus can be determined. It may be remarked here that, on the contrary, there is impairment of fremitus over areas of pulmonary collapse.

Auscultation usually shows the continuance of the râles due to the preceding bronchitis. In addition to these coarser dry and moist râles there is also heard fine moist crackling over the area of pulmonary consolidation; these fine subcrepitant râles are heard both during inspiration and expiration. Pure bronchial breathing, such as is heard in croupous pneumonia, is by no means constantly present. Over large areas of catarrhal pneumonia, when the small bronchial tubes are comparatively unobstructed, it may exist; but, on the other hand, there may merely be weak diffused blowing breathing.

In adults an equally grave type of acute catarrhal pneumonia is not of such common occurrence. Cases are met with, however, occurring especially in subjects whose systems are depressed--as, for instance, by overwork--in old or feeble persons, or in connection with diphtheria, typhoid fever, or influenza. The {361} disease may then run a course closely resembling that described above as found in children, the rapidly developing interference with aëration of the blood, the speedy failure of cardiac power, and the appearance of grave nervous symptoms all being strongly marked. Such cases constitute a notable proportion of what is commonly styled typhoid pneumonia, especially in the aged, the disease being often in reality catarrhal instead of croupous. I have also met with rapidly fatal catarrhal pneumonia developed during the course of typhoid fever, particularly during the later stages of cases marked by considerable bronchitis and great nervous depression. In one instance the patient, a young man of twenty-six years, who had been much exhausted by mental worry and anxiety, passed through a well-marked attack of typhoid fever with moderate pyrexia, but with decided nervous symptoms. Convalescence seemed established on the twenty-first day, when he was carelessly allowed to sit up in a chair, and while there was exposed to a draught of air; he felt chilly, fever reappeared with cough, but no rusty sputa; centres of catarrhal pneumonia developed in the lower lobe of the right lung, then in the middle lobe; the fever varied from 101½° or 102° in the mornings to 103½° or 104° in the evenings. On the seventh day there was a sudden fall to 99°, with a rise in the afternoon to 106°; centres of inflammation appeared in the left lung. For the next five days there were remarkable fluctuations of temperature, the range being from 100½° or 101° in the morning to 106° and 106½° in the evening. The variations in the pulse-rate were not so marked. Respiration was hurried and imperfect. Nervous symptoms of a typhoid and ataxic nature developed, and death occurred on the twelfth day. Considerable daily fluctuations in temperature, though rarely so regular and extreme as in this case, are often noted in catarrhal pneumonia, and are of some diagnostic importance. I have many tracings to show the remittent though atypical course of the pyrexia of this disease. Such grave cases of acute catarrhal pneumonia are very fatal, even in adults, scarcely less so indeed than in children; and when recovery occurs the convalescence is protracted, and often interrupted by more or less serious renewals of catarrhal inflammation with constitutional disturbance.

As already remarked, the pulse-rate, which soon becomes rapid, 110 to 124, does not vary as much as the temperature; and even during marked remissions of the pyrexia the pulse usually continues rapid. The appetite is greatly diminished or lost; the tongue is coated, often heavily so; vomiting is not often present spontaneously, but may be excited by the spasmodic attacks of cough. The respirations are hurried and superficial, frequently rising to 40, 50, or 60 in the minute in adults, and this rapidity persists during remissions of the fever just as does the rapidity of the pulse. As a rule, it is not possible to observe any marked difference in the movements of the two sides, owing to the irregular distribution of the foci of disease. The cough is frequent and may be painful. It is apt to occur in paroxysms, and the spells may be so severe as to cause alarming interference with respiration, and also to induce serious exhaustion.

The sputa are at first scanty and consist of tenacious mucus, which may possibly show fine blood-points, but which are quite different from the rusty-colored sputa of croupous pneumonia. Later the sputa become more abundant and less consistent, being much affected by the amount of bronchitis attendant.

The results of physical examination are much more satisfactory in adults than in children, owing partly to the less frequency of pulmonary collapse as a complication, and partly to the assistance obtained from the more careful study of the vocal fremitus and resonance possible in the former. Inspection will not show inspiratory retraction of the base of the chest to anything like the extent seen in children, owing to the greater rigidity of the thoracic walls. {362} In the later stage of the disease, however, when considerable infiltration and obstruction of the lungs has developed, such retraction and also an inspiratory depression of the suprasternal space may be noted. Palpation does not give such clear results as in croupous pneumonia, yet careful observation will show relative increase of fremitus over the affected areas. Auscultation of the voice usually gives valuable results. They are not constant, however, nor is it common, even when a considerable area is consolidated, to meet with such bronchophony as in the second stage of croupous pneumonia. Still, it is nearly always possible to detect some alteration of the vocal resonance by comparing corresponding portions of the two sides; and this, as contrasted with the negative results in bronchitis, possesses high value. The respiratory murmur is usually feeble and blowing over the patches of catarrhal infiltration. In some cases it is as intensely bronchial as in the croupous form; but more commonly the greater or less obstruction of the bronchioles renders it weaker and more distant and diffused. I have observed considerable areas of consolidation due to catarrhal pneumonia, over which the respiratory murmur was so feeble as to suggest the presence of moderate pleuritic exudation. Râles are apt to be present at all stages of the disease. Usually they are fine subcrepitant or fine dry crackling râles, audible in both inspiration and expiration; and even over consolidated areas these may be audible, being doubtless transmitted from the fine bronchioles.

As the case progresses toward resolution the râles become larger and looser. It often happens that the râles are variable, changing in character, extent, and position from day to day vastly more than occurs in croupous pneumonia.

Percussion gives valuable data if practised with care over symmetrical areas of the two lungs. From such comparative study alone can satisfactory results be obtained, since in many cases the areas of disease are too small or not sufficiently superficial to yield more than relative dulness. But it must happen rarely that spots are not found where resonance is at least relatively impaired, while of course in some cases actual dulness is readily detected. It has been stated that collapse of the lung is a comparatively rare complication in adults, yet careful study of the physical signs from day to day will occasionally show its existence in a marked degree. It may occur in a striking manner in the subacute catarrhal pneumonia of emphysematous subjects; but in acute cases also considerable areas of the affected lung may quickly pass into a state of collapse. In a fatal case of the acute form in a young man I observed the abrupt development of the signs of pulmonary collapse over the whole lower lobe of the right lung, requiring care to avoid the error of supposing a considerable pleuritic exudation to have supervened, but passing away in the course of thirty-six hours with renewed expansion of the lobe and restoration of the previously existing physical signs.

It is not necessary to give any detailed discussion of the other symptoms of acute catarrhal pneumonia as occurring in adults--the atypical remittent type of fever; the rapid pulse and breathing; the digestive symptoms, anorexia, thirst, occasional nausea, and a comparatively frequent tendency to diarrhoea; the nervous restlessness and depression, with delirium supervening, at first slight, later more active, and toward the close of fatal cases of such violence as to require restraint, alternately with deepening stupor from exhaustion and defective aëration of the blood. Albuminuria may be present in a slight degree toward the close of severe cases. When death occurs in these acute cases it usually does so from the tenth to the sixteenth day. In children it may occur suddenly during or after a violent paroxysm of cough, or an attack of convulsions may be the immediate cause of death. More commonly death is preceded by evidences of increasing intensity of interference with the aëration of the blood, and with deepening stupor and nervous {363} disturbances such as have been described. The degree of cardiac failure present is to be ascribed rather to nervous exhaustion than, as in many cases of croupous pneumonia, to the action of hyperpyrexia on the muscle of the heart. The extreme interference with respiration in catarrhal pneumonia is readily accounted for, not only by the extent of lung-tissue actually involved in the process, but by the associated bronchitis with swelling of the mucous membrane, by the accumulated bronchial secretions, and by the frequent complication with collapse. When recovery is to follow, the disease declines gradually and irregularly, slight recurrences of fever and renewed catarrhal irritation being observed from time to time. These exacerbations may not rarely be traced to atmospheric influences or to trifling indiscretions on the part of the patient. The pain declines gradually; and the pulse-rate also falls, but even after the temperature has become normal some degree of rapidity of the pulse is apt to remain for a considerable time. The physical signs gradually disappear: the respirations, like the pulse, remain somewhat rapid, or at least are for some time readily accelerated; and there is apt to be some cough remaining, with gradually decreasing muco-purulent expectoration. The digestive functions are also apt to be left in an enfeebled condition, and the recovery of full nutrition and health is often slow. A peculiar sensitiveness of the general system is frequently noted after this disease, so that morbid processes, especially of catarrhal type, are readily excited.

As would be expected, catarrhal pneumonia frequently presents much less violent symptoms and runs a much less acute course than above described, so that it may be said to assume a subacute or chronic form.

In children this may occur as the result of an acute attack, the severe symptoms gradually subsiding, and passing into a less violent but persistent type. In other cases the disease assumes this form from the beginning, and such instances are more commonly noted after ordinary bronchitis of moderate severity or after whooping cough. In adults this form also is less common than in children. It is met with as an intercurrent affection in certain cases of phthisis; and not rarely the exacerbations of that disease are due to the development of centres of catarrhal pneumonia which too often become later the seat of an extension of the tuberculous process. It occurs in this form also in the old and cachectic, and doubtless proves the undetected source of death in many cases where the end is preceded by irregular pains and by some signs of hypostatic infiltration of the lungs. In a feeble and exhausted state of the system at all ages it is liable to be induced. At times this is brought about by a series of recurring slight catarrhal attacks, gradually deepening into a subacute process of catarrhal pneumonia; while in other cases a more powerful disturbing cause will in such states of system directly induce this type of the disease. It develops insidiously. There is little or no pain. The fever is highly irregular; the maxima usually occur in the evening and reach 102° or 103°, but there may be such marked remissions as to make the case closely simulate one of intermittent malarial fever complicated with bronchitis, and I have known such an error to be made in repeated instances. In some cases, especially in the old and feeble, there may be very little fever, at least until the disease is more fully developed. The dyspnoea is not urgent; the pulse is not extremely rapid; and cough may actually seem diminished if the disease has originated in the course of severe bronchitis. The physical signs develop slowly, but may eventually appear over considerable areas of lung-tissue. In this way with an irregular fluctuating pyrexia, presenting from time to time marked exacerbations, with an equally varying amount of cough and muco-purulent expectoration, and with marked and progressive debility and emaciation, these forms of catarrhal pneumonia pursue a course extending over many weeks or months. Complete recovery is still possible, after a tedious convalescence. Commonly, {364} however, some permanent lesion of the lungs, as emphysema, dilatation of the bronchial tubes, or circumscribed induration of the lung, will remain as sequels. In a large proportion of cases a fatal result finally follows, more commonly from the passage of the morbid process into pulmonary phthisis usually associated with true tuberculosis; while in some cases acute miliary tuberculosis supervenes and proves rapidly fatal. Undoubtedly, however, cases of chronic catarrhal pneumonia may continue purely as such, with recurring exacerbations at irregular intervals from the development of new centres of disease, until death is finally induced by exhaustion.

COMPLICATIONS AND SEQUELS.--It is needless to repeat what has been said as to the essential connection between catarrhal pneumonia and bronchitis, so that the latter is to be regarded as an invariable symptom and attendant rather than as a complication. As might be expected also, catarrhal laryngitis of varying degrees of severity is of comparatively common occurrence. Especially in cases occurring in connection with measles, where the upper respiratory tract is already inflamed, the increased intensity of the laryngitis may induce so much swelling as to cause some mechanical obstruction to respiration which will arouse fears of pseudo-membranous formation, and which, during the spasms of cough and dyspnoea which are apt to occur occasionally, will closely simulate true croup. Pleurisy rarely appears in such a high degree as to constitute a serious complication. When the areas affected are superficial, there is apt to be circumscribed plastic exudation on the corresponding portions of the pleura. Less frequently quite extensive plastic pleurisy occurs, with layers of exudation sufficiently thick to modify the physical signs; and in still more rare instances does fibro-serous effusion occur. I have noted the occurrence of purulent pleurisy, as has Jürgensen; and in two cases it was found to be associated with subpleural purulent foci, one at least of which had ruptured. In the other cases the purulent character of the pleurisy was presumably due to the constitutional dyscrasia. Allusion has already been made to the occurrence of emphysema and bronchiectasis in connection with catarrhal pneumonia, especially of the subacute and chronic varieties. The observations of Delafield on the tendency of the catarrhal inflammatory process to extend laterally through the bronchial wall into the peribronchial zones of lung-tissue are of special interest in their bearing on the liability to dilatation of the bronchial tubes and to deep-seated circumscribed indurations of lung-tissue as sequels of catarrhal pneumonia.

Gangrene of the lung I have known to occur as a complication in one case of extraordinary severity, but in which recovery ultimately followed a very tedious process of reparation. It was attended with recurring attacks of hæmoptysis. The case occurred in a young man of twenty-four years of age: the lesions existed chiefly over the right back, though there were smaller centres elsewhere; and the spot of gangrene and from which the hemorrhages occurred was near the right root. He was four months in bed; his convalescence extended over a year; evidences of induration at the above spot lasted five years; and now, eight years after the attack, he is in vigorous health, though still with slight cough.

Pneumothorax may occur as a sequel in protracted cases in consequence of the rupture of a subpleural abscess. I have elsewhere reported cases of this, and Steffen has also reported two instances.

Tuberculosis occurs in various ways in connection with catarrhal pneumonia. There may be a development of acute general miliary tuberculosis, owing to the depressing and irritating effect of the disease upon a constitution strongly predisposed to tuberculosis. Or tuberculous pulmonary phthisis may ensue, either directly as a complication or as a sequel to ulcerative changes of inflammatory nature in the lung. Finally, those who have passed through {365} an attack of catarrhal pneumonia are usually left with such vulnerability of system that any predisposition to phthisis or to tuberculosis is very apt to be readily called into activity. It seems highly important to note this close and complicated connection between catarrhal pneumonia, in its various types and even in its mild and circumscribed form, and subsequent organic disease.

Further evidence of the profound disturbance of nutrition often effected by an attack of this disease may be found in the occasional development of marked rachitis, and in the much more frequent establishment of subsequent anæmia and debility, which prove obstinate and are associated with a high degree of susceptibility of the system to morbid influences, and which are doubtless, in some instances at least, dependent upon impaired primary assimilation due to lesions of the intestinal canal, which existed as complications of the original attack of catarrhal pneumonia. It has been mentioned that gastro-intestinal irritation is often present, both in the acute and in the more chronic forms, and this may reach such a high degree as to justify the name of a complication. It has seemed to be especially in these cases, or in those where, owing to the subsequent vulnerability of the system, gastro-intestinal catarrh occurs as a sequel, that the serious impairment of nutrition above mentioned is most likely to ensue.

Lastly, allusion must be made to the frequency with which severe nervous symptoms appear, especially during the later stage of the attack. As has been seen, convulsions are not rare in children, while at all ages active delirium and extreme restlessness, often requiring restraint, are of frequent occurrence. These cannot be attributed, as a rule, to uræmic intoxication, but are to be referred to the high systemic irritation, the great nervous exhaustion, and the marked interference with respiration and aëration of the blood. It is probable also that circumscribed areas of lepto-meningitis, or even of tuberculous meningitis, are of occasional occurrence in these cases.

DIAGNOSIS.--The direct recognition of catarrhal pneumonia in its acute stage is not always free from difficulty, while both in the acute and chronic forms there are certain conditions with which care must be used not to confound it.

In the first place, it is important to recognize at the earliest moment the development of the pneumonic process during acute bronchitis of the finer tubes. In all cases of the latter, especially in children and in patients of debilitated system, this occurrence must be constantly apprehended. Its occurrence may be strongly suspected if sudden rise in the fever and in the rate of respiration and pulse is noted, though if the areas affected are small, scattered, or deeply seated it may not at first be possible to demonstrate it. It must be remembered also that in the capillary bronchitis of children the fever and disturbance of pulse and respiration may be aggravated quite abruptly from extensions of the disease, so that actually it must be recognized that in such cases the presence of small pneumonic centres can only be assumed, but can neither be proved nor disproved. The course of the pyrexia may afford some assistance, since I believe more marked diurnal variations, amounting at times to distinct remissions, will be noted in cases of catarrhal pneumonia than in those of severe bronchitis not so complicated. In adults less hesitation need be felt in admitting the development of pneumonic foci under such circumstances, even though the physical signs are negative. Usually, however, carefully repeated examination will soon reveal the signs of infiltration in irregularly disposed areas; and I suspect it must be infrequent that the close study of the relative physical signs afforded by examination of the corresponding areas on the two sides of the chest will not afford substantial ground for diagnosis.

It must always be remembered that areas of consolidation arising in the {366} course of severe bronchitis of the finer tubes may be from collapse, and not from pneumonia. This is especially apt to be the case in children, but occurs not rarely in feeble adults. The diagnosis of catarrhal pneumonia from mere collapse must therefore be carefully considered. The occurrence of collapse, though it may be marked by sudden and severe increase of dyspnoea, pulse-rate, and distress, is not accompanied by a corresponding rise of temperature; and this is a point of capital importance. Again, the development of the physical signs is usually much more abrupt than where catarrhal pneumonia is occurring. Considerable areas of dulness on percussion appear in the course of twelve or twenty-four hours, between the successive visits of the physician, without corresponding increase of fever; and these areas may subsequently present marked peculiarities, at times disappearing almost as abruptly, to be succeeded by similar areas in other portions of the lungs, though at times also they persist and pass through the changes already described. The physical signs furnish further assistance. Retraction of the base of the chest during inspiration is much more common in collapse, especially when the areas are at all extensive and when they occur in the lower lobes, since there is necessarily a reduction in the volume of the lungs; and this, added to the inability to inflate the affected lobules, induces this important sign, which should always be carefully looked for. The dulness over collapsed lung-tissue is rarely as marked as over extensive areas of catarrhal pneumonia; the vocal resonance and fremitus are diminished; râles are wanting or are feeble and transmitted; and again, it must be mentioned that the physical signs present remarkable variations within short periods of time. It is, however, necessary to suspect the existence of pneumonic areas in cases of severe bronchitis where portions of lung become collapsed, and continue so, while the general symptoms indicate persistence of inflammatory action. The differential diagnosis is therefore in many instances rather as to the relative proportion of these factors than as to the total absence of either.

Catarrhal may be confounded with croupous pneumonia. This error may most readily be made if the case be not seen until a consolidated area of considerable extent is present, since, as we have seen, in some instances the foci of catarrhal pneumonia may chiefly occupy one lung and may coalesce. Even then, however, the dulness of percussion rarely corresponds with the outline of the lobe, and is rarely as complete as in croupous pneumonia, nor are the bronchial respiration, the bronchophony, and the exaggerated vocal fremitus as pronounced, for the simple reason that the consolidation is not so uniform, and that many of the smaller bronchial tubes are more or less obstructed by swelling of the mucous membrane or by the accumulation of viscid secretions. It will rarely happen, moreover, that strong efforts at respiration--induced, if necessary, by having the patient cough during the auscultation, so as to ensure a full inspiration--will fail to develop subcrepitant râles at some point of the catarrhal consolidation. To this must be added the information drawn from the history of the case; the character of the cough and sputa; and, above all, the atypical course of the pyrexia, and the fact that carefully-repeated examinations will show frequent and abrupt variations in the physical signs around the margins of the affected area. If the case is observed during its development, there will be less difficulty in making a correct diagnosis. The process is very rarely unilateral throughout its development; and the evident bronchitis, the development of irregularly scattered foci of partial consolidation in both lungs, and the frequent coexistence of collapse, combined with the absence of the characteristic symptoms and course of the croupous form, make the nature of the case apparent.

The diagnosis of ordinary pleurisy with effusion from catarrhal pneumonia presents no difficulty. But, on the other hand, it is not easy to recognize the {367} occurrence of a moderate pleuritic effusion complicating a catarrhal pneumonia. The fact that the lower lobes of both lungs are apt to be involved in the pneumonic process interferes with the displacement of the heart, and the enfeebling of the respiratory and vocal phenomena may be attributed to bronchial obstruction or to collapse. A careful study of the outline of the dull area, and of the effect upon it of changes in the position of the patient's body, has proved of service. After all, this is a rare complication; but not so rare is the coexistence of plastic pleurisy with catarrhal pneumonia, and this also may give rise to doubt in the diagnosis. An area of dulness appearing near the base and extending with moderate rapidity, attended with bronchial irritation, with irregular fever of slight or of moderate degree, and with some evidences of engorgement of the lower part of the opposite lung, and presenting over the affected area, in addition to marked percussion dulness, bronchial respiration not of intense concentrated type, distant bronchophony, no increase of vocal fremitus, and crackling râles irregularly scattered over the affected area, represent a clinical condition, occasionally met with in adults, which requires care to ensure its proper interpretation. I have observed crackling râles in particular in such cases, which might have been regarded either as intrapleural or as developed in the finest bronchioles. It will be observed, however, that the degree of dulness is excessive for a mere plastic pleurisy; that the respiratory and vocal signs, while not typical of croupous consolidation, are yet far more developed than would be consistent with the presence of a quantity of plastic pleural exudation sufficient to cause such dulness; that any such grade of plastic pleurisy is very rare; and that the general symptoms and the course of the disease are indicative of much more gravity than would attach to such a pleuritic process if it were to exist. It is altogether probable that there has been here a coexistence of catarrhal pneumonia with a moderate degree of plastic exudation on the corresponding part of the pleura.

Again, it is essential to distinguish catarrhal pneumonia from acute miliary tuberculosis with special localization in the lungs and meninges. This diagnosis may present marked difficulties both in children and in adults, but of course chiefly in the former, and especially at a late period of the case, when cerebral symptoms, closely simulating those characteristic of tubercular meningitis, may have appeared. The irregular fever, the marked disturbance of pulse and respiration, with evidence of diffuse bronchial irritation, but out of proportion to the physical signs of consolidation, the occasional vomiting in the early stage, and the appearance of nervous symptoms, are present in both conditions. But in tuberculosis there may be high fever before any marked evidences even of bronchial irritation appear; there is not so much bronchitis to aid in explaining the dyspnoea; there is not so much tendency to pulmonary collapse, and the physical signs present are more persistent; the pulse presents the characteristic successive stages of alteration; vomiting is apt to be more frequent, while the diarrhoea which is often present in catarrhal pneumonia is replaced by constipation; the Cheyne-Stokes respiration is more apt to appear; and, finally, an ophthalmoscopic examination may reveal retinal tubercles. It remains true, however, that in some cases it must evidently be wellnigh impossible to decide whether the case is one of acute tuberculosis, with a high grade of bronchitis, and very probably with some centres of pneumonic infiltration associated, or one of catarrhal pneumonia developing out of a severe bronchitis. It must be remembered, moreover, that even when the case has begun as one of catarrhal pneumonia there is a tendency to the development of tuberculosis, both pulmonary and general; so that it may be found after death that the nervous symptoms, which were reasonably ascribed to congestion, to high temperature, to prolonged and exhausting nervous irritation, and to the effect of imperfectly aërated blood, are in reality connected with the {368} presence of miliary tubercles in the meninges, while at the same time these have also been developing around the pneumonic foci in the lungs.

It is no less important to bear in mind the necessity for close study in distinguishing between chronic catarrhal pneumonia and phthisis. There are not a few cases of the former where the protracted irregular fever of hectic type, the progressive debility and emaciation, the moist râles, the areas of altered percussion resonance, possibly the signs of a dilated bronchus, and the purulent sputa, may closely simulate true phthisis, but yet which microscopic examination of the sputa for bacilli and elastic fibre, and the effect of treatment and climatic change, prove to be merely inflammatory. On the other hand, it appears undoubted, from the standpoint of clinical observation, that in many cases, especially where a predisposition exists, catarrhal pneumonia terminates in phthisis.

DURATION, TERMINATIONS, PROGNOSIS.--The duration of this disease is highly irregular, and care must be taken not to confound the subsidence of the marked general symptoms with a full restoration of the affected areas. A considerable period is required for this latter process to be effected, and during this interval the lung-tissue continues in a highly sensitive and vulnerable state. Speaking with reference to the obvious symptoms, however, it may be said that mild acute cases may terminate in seven to ten days; fully-developed acute cases, in fifteen to twenty-five days; while the subacute and chronic forms may last several or many months.

Death may occur in from two to four days, especially in weak young children, while more commonly the fatal result occurs from the seventh to the tenth day. Of course in the chronic form death may occur after many weeks or months.

The various terminations are in complete recovery; in apparent recovery, but with vulnerable lungs or general system; in partial recovery, but with residual lesions, such as bronchial dilatation or emphysema; or the disease may pass into the chronic form, associated with chronic bronchitis, or it may lead to the development of acute tuberculosis or of chronic phthisis.

The rate of mortality of catarrhal is much higher than that of croupous pneumonia. Excluding the mild circumscribed form, if such is admitted to exist, as I believe it does, the mortality varies from 30 to 60 per cent. It is apparently less fatal when occurring in the course of measles than in connection with some other diseases, as diphtheria or whooping cough. The nature and tendencies of this disease make it evident that debility and frailty of the patient would render catarrhal pneumonia much more fatal. So it is found that in infants within the year death almost constantly follows, and in older children of bad constitution, especially in those who are scrofulous or rachitic and subjected to malhygienic influences, it is almost equally fatal. After puberty the mortality is chiefly influenced by the constitutional state of the subject and by the extent of the pneumonic process.

The greater tendency to pulmonary collapse and to severe capillary bronchitis in young children justifies Jürgensen's generalization, that before the age of puberty the danger from catarrhal pneumonia grows greater in proportion to the youth of the individual. Partly because the disease is more apt to assume the subacute form in feeble and sickly individuals, partly because in this form the pneumonic process is more apt to run into destructive lesions of the lung-tissue or to induce tuberculosis, it is found that the mortality from the subacute is even greater than from the ordinary acute form.

It is needless to detail the special symptoms of unfavorable significance. The most important considerations to guide us in prognosis are, therefore, the age, constitution, and vital resistance of the individual; the extent of the pneumonia and of the associated pulmonary collapse and capillary bronchitis; the degree of gastro-intestinal irritation; the vigor of the circulation {369} and respiration, and the manner in which aëration of the blood is maintained; and, finally, the grade of the fever and the character of the nervous symptoms.

TREATMENT.--It is difficult to lay down definite rules for the treatment of catarrhal pneumonia, as the indications are extremely variable and complicated.

In the first place, it is scarcely necessary to call attention to the importance of guarding against the development of this disease in all cases of bronchitis occurring in children or in delicate adults. This care is essential not only in idiopathic bronchitis, but in those general diseases, such as measles and whooping cough, in which bronchitis is constantly present. As children of bad constitution and those exposed to depressing hygienic conditions, such as over-crowding, bad air, and the like, are most liable to become attacked with this form of pneumonia during the course of a bronchitis, it is especially in such cases that our precautions must be most stringent. They should include a strict attention to the condition of the sick-room, which should be well ventilated, but free from drafts, the temperature not being allowed to rise above 68° or 70°, and the air being kept moist by the generation of steam. The diet must be carefully regulated, so that the child's strength shall be as far as possible maintained, and stimulants must be used if indicated by weakness of the pulse or by a tendency to failure of respiratory power. Stimulating applications should be made to the chest, both to serve as counter-irritants and because they stimulate respiration. It would be manifestly unsuitable to enter here into the details of the treatment of such cases of bronchitis, and the above remarks have been made chiefly for the purpose of calling attention in an emphatic manner to the great importance and value of strict and thorough treatment of all severe cases of bronchitis, especially in children, not only with a view to the prompt cure of the primary disease, but because thus also will the development of the more serious conditions of pulmonary collapse and of pneumonia most surely be prevented.