Chapter IX: Dysentery

DEFINITION AND SYNONYMS

=Definition.=—The designation dysentery refers to a symptom-complex of (1) small, frequently passed mucous or muco-sanguinolent stools and (2) pains connected with spasm of the sphincter ani (tenesmus) or intestinal gripings (tormina).

The condition may be set up by numerous causes but of these two so outweigh the others that it is usual to have in mind either bacillary or amoebic dysentery when the term is employed.

=Synonyms.=—The Bloody Flux. French: Dysenterie. German: Ruhr.

GENERAL CONSIDERATIONS

As will be noted in the sections dealing with amoebic and bacillary dysentery our present knowledge of these conditions is of recent date. There was so much that was etiologically, epidemiologically and clinically contradictory that the subject was impossible of elucidation until the existence of a group of dysentery bacilli was generally accepted, following the reporting, in 1898, by Shiga, of his bacillus of dysentery.

Although Hippocrates was the first accurately to describe the
disease we now know as dysentery yet there is good ground for
believing that the disease existed in Egypt and India for centuries
before Christ.

Many of the older writers failed to differentiate conditions which
showed admixtures of mucus and blood in the stools from those with
blood alone.

Commencing with the last century, authorities have considered
the association of mucus with the blood as essential in clinical
diagnosis.

It is interesting that with a better knowledge of etiology we are
now recognizing as of dysenteric nature diarrhoeal conditions in
which there is an absence of the typical stool of dysentery.

Our views as to the etiology and epidemiology of bacillary
dysentery have been fairly definite for at least twenty years,
while those relating to amoebic dysentery, notwithstanding the
important researches of Kartulis, Councilman and Lafleur, Schaudinn
and others have remained rather chaotic until quite recently.

_The Term Dysentery._—By the term dysentery we understand a symptom-complex of more or less characteristic stools and more or less characteristic pains.

As a rule the stool is composed of one or more teaspoonfuls of
greenish yellow or dirty brown mucus, the altered blood being
intimately admixed with the mucus, or we may have a whitish to
grayish muco-purulent mass with streaks or flecks of blood on the
outside. These mucoid masses may be found suspended in serous,
sanguineous or more or less feculent discharges which are usually
small in amount and passed with much frequency.

The terms tormina and tenesmus are the ones used to designate the
characteristics of the pains of dysentery, tormina for the griping
colicky pains, which center about the umbilicus or run in the
direction of the large intestine, and tenesmus for the painful
spasmodic contractions of the sphincter ani to which is due the
sensation of lack of ability to complete the act of defecation
leading to straining and justifying Manson’s description “glued to
the commode.”

It is usually stated that the nearer the dysenteric process is to
the rectum, the greater the tenesmus and the nearer to the caecum,
the greater the tormina.

THE MODERN CLASSIFICATION OF DYSENTERIES IS BASED ON ETIOLOGY RATHER THAN UPON CLINICAL MANIFESTATIONS

Owing to the great importance of the two main kinds of dysentery,
amoebic, or that caused by _Entamoeba histolytica_, and bacillary,
or that caused by some strain of _Bacillus dysenteriae_, we shall
consider them separately from the other causes of the dysenteric
symptom-complex.

=A. Dysenteries caused by animal parasites.=

_Protozoal dysenteries._

1. Amoebic dysentery (_Entamoeba histolytica_).

2. Flagellate dysenteries (_Lamblia intestinalis_, _Trichomonas intestinalis_ and _Chilomastix mesnili_).

While in adults these intestinal flagellates usually cause only
a diarrhoea, with at times marked nervousness, they may produce
dysenteric symptoms in young children. The onset in children under
three years of age may be insidious and attended with fever. The
stool contains much mucus with only a little blood.

In cases of amoebic dysentery, the diarrhoeal attacks, which at times occur, are often associated with an abundance of flagellates, which may well be the cause of the complication. Cases of dysenteric diarrhoea have been reported from Gallipoli in which _Lamblia (Giardia)_ were apparently the only parasites involved. Such stools are often of a yellow ochre color. Relapses are common features of _Lamblia_ infections. _Lamblia_ is an inhabitant of the upper intestine while _Trichomonas_ and _Chilomastix_ belong to the large intestine, especially in the region of the caecum. While these last named flagellates are often found in the stools of those convalescent from dysentery there is a general opinion that they are nonpathogenic. These organisms may be present in diarrhoeal conditions in which case it is common to designate such diarrhoeas as flagellate diarrhoeas. Fantham and Porter have reported 187 cases of pure lambliasis.

In diagnosis it is important to recognize the encysted _Lamblia_.
These are oval cysts, about 10 × 7µ and show a curved central line,
with two lateral dots. When stained these dots show as chromatin
areas. These cysts may be found in the faeces in great numbers. The
vegetative _Lamblia_ has 4 pairs of flagella, is about 15µ long and
has a tumbling motion. Calomel alone or calomel and ipecac give
good results at times. Enemata of organic silver salts may be of
benefit.

Porter recommends bismuth salicylate. Low has noted the tendency of
lambliasis to recur and thinks many of the reported cases of cures
are only temporary. His experience with bismuth, salol, thymol and
cyllin has not been encouraging.

It is well known that lambliasis is of rather frequent occurrence
in mice and rats so that these rodents may be factors in spreading
the infection through the agency of their faeces deposited about
human food.

Of other drugs recommended in treatment Dobell and Low have had no
success with methylene blue, turpentine or beta-naphthol. These
authors failed to find any increase in either large mononuclears or
eosinophiles in a case of the infection.

Since Lamblia inhabit the upper parts of the small intestine, it
may be that the administration of drugs by the duodenal tube will
prove an effective method of treatment. Owens reports successful
results in the treatment of amoebic dysentery from ipecac so
administered. Stiles has recommended sulphur in lambliasis.

3. Ciliate dysenteries (_Balantidium coli_).

While various ciliates may cause a severe type of dysentery it is very exceptional that others than _Balantidium coli_ do so. This oval ciliate is from 60 to 100 microns long by about 50 to 70 microns broad. It is a commensal of hogs and the disease in man is usually found in those having the care of hogs. Infections have been reported from various parts of the world, temperate as well as tropical regions. These ciliates may be found in the faeces of persons apparently well but in such cases symptoms may eventually appear. The parasites multiply in the submucosa and the pathologic process is similar to that observed in the large intestine in amoebic dysentery.

The parasite is so large and has such an active motility that
it would be impossible to fail to detect it in a microscopic
examination of the faeces. Encysted parasites are round. The
onset is rather insidious with diarrhoea which may be followed by
dysentery. A severe form of anemia may be noted.

Ipecac, emetine, arsenic and quinine appear to be of little
value in the treatment, but Walker considers the organic silver
compounds, as protargol, etc., of value. Methylene blue enemata
(1-3000) and 2-grain pills by mouth have been recommended.

4. There are also dysenteric manifestations noted in the terminal stages of kala-azar (_Leishmania donovani_) and in algid pernicious malaria (_Plasmodium falciparum_). These conditions are taken up under the diseases kala-azar and malaria.

Wenyon noted a case of coccidial infection (_Isospora hominis_)
in which there was a dysenteric syndrome. There have been about
seventy cases of infection with this parasite reported, chiefly
from soldiers serving in Gallipoli. The usual opinion is that they
are nonpathogenic parasites. The oocysts are ovoid, with one end
narrowed, and measure 28 × 14 microns. There are two sporocysts,
each of which contains four sporozoites. The cyst when first passed
is unsegmented.

_Helminthic dysenteries._—1. In addition to the protozoal causes above noted we may have dysenteric symptoms following infections with trematodes, especially _Schistosoma mansoni_ and _S. japonicum_. In these cases we have mucus coating the stool with more or less clotted blood in which mucus we may find the diagnostic ova. A rather high eosinophilia is present.

2. Infections with _Gastrodiscus hominis_ also give rise to
dysenteric manifestations.

3. A very small cestode, _Heterophyes heterophyes_, has been noted
to cause a condition suggestive of dysentery.

4. In 1902, Brumpt noted the finding of a nematode,
_Oesophagostomum brumpti_, in the large intestine of an African
native, which caused dysenteric symptoms and, more recently,
another species, _O. stephanostomum_, has been reported as causing
a fatal dysentery in a Brazilian at Manaos.

5. There have also been reported cases with dysenteric
manifestations which were apparently connected with intestinal
myiasis.

=B. Dysenteries caused by bacteria.=

1. Those caused by either the more toxic, nonacid mannite strain of Shiga, or the less toxic, acid mannite strains of the Flexner group.

2. Morgan has reported as the cause of certain bacillary dysenteries a bacillus known as B. Morgan No. 1. It is motile, produces indol, and in glucose bouillon gives a very slight amount of gas. It does not change mannite and does not produce a primary acidity in litmus milk. This organism is a frequent cause of summer diarrhoea of children. Flies from houses with such cases often show Morgan’s bacillus.

Paratyphoid infections may give the clinical picture of a colitis
and such cases at times show a large amount of blood in the
dysenteric stools. Usually the symptoms are rather those of an
entero-colitis or a gastro-enteritis.

3. In Japan, dysentery-like epidemics of a very fatal disease, termed _ekiri_, occur among young children. The organism is very motile, producing gas and acid in glucose, but not in lactose media. It is reported at times to show indol production. Apparently a member of the Gärtner group.

4. Spirillar dysentery. LeDantec has reported a type of dysentery which shows the presence of great numbers of spiral forms. These are Gram negative and noncultivable. It is in question whether they belong to the bacteria. There is no fever in this type of dysentery.

5. Other bacterial causes. Cases of dysentery have been reported as caused by _B. pyocyaneus_, streptococci, atypical _B. coli_ and organisms of the Gärtner group.

In a _Pyocyaneus_ infection the color of the stools would be
suggestive. This cause should be borne in mind in the dysenteric
infections of debilitated children in the tropics. Some of the
cases of so-called ptomaine poisoning due to members of the Gärtner
group have clinical similarities to dysentery especially at the
commencement of the attack.

=C. Dysenteries resulting from mechanical irritants or poisonous substances.=

A very interesting form of poisoning which gives rise to serious
illness or death and is attended with marked abdominal pain and
manifestations of dysentery is that reported from North China
through the use of short lengths of bristles which are given mixed
with the food.

Various irritant metallic poisons as arsenic, antimony and mercury
may give rise to dysenteric symptoms. In cancer and syphilis of the
rectum there may be a suspicion that the process is an ordinary
dysenteric one.

Intussusception shows marked tenesmus with bloody rather than
muco-sanguineous stools.

While dysenteric symptoms may be present in the terminal stages
of various chronic diseases, especially tuberculosis and cardiac
affections, yet it is in chronic nephritis, leading to uremia, that
we may see symptoms of a marked catarrhal or even diphtheritic
colitis.