Diarrhea appears promptly
In severe cases, the feces may contain large amounts of blood, mucus,
and polymorphonuclear leukocytes.
In the fully developed severe form of the disease, the stools may
ultimately consist of only frequently evacuated masses of sticky, bloodstained mucus,
which contains enormous numbers of dysentery bacilli.
Abdominal pain may be severe. The evacuations may be involuntary and
accompanied by very painful straining. Bacillary dysentery usually is a self-limited
disease, running its course in about 2 weeks.
Many patients have only transient diarrhea or no intestinal symptoms.
Shigellosis should be suspected from the clinical course, even though, mild cases with
generally normal stools are common.
e. In the Military. In large groups of men, as in the military, the disease often
smolders unrecognized for some weeks before it breaks out in a fashion, which attracts
attention.
2-7.
AMEBIASIS (AMEBIC DYSENTERY)
a. Identification. Amebic dysentery (Figure 2-2) may be acute or chronic, with
an incubation time varying from a few days to several months. It is caused by an
ameba, Entamoeba histolytica, which lives in the colon of man.
b. Development. A resistant form (cyst) of this protozoan (single celled animal)
is passed in the feces. Susceptibles ingest the cysts with food or water containing the
cysts. The active form (trophozoite) then breaks out of the cyst and invades the large
intestine, where it multiplies. It may also spread via the bloodstream to the liver, lungs,
brain, and skin.
c. Signs/Symptoms. Symptoms, which vary in character and severity, may be
present in one of three recognized forms:
Abdominal discomfort and diarrhea, alternating with constipation
Chronic diarrhea
Acute dysentery, in which the amount of blood and mucus passed, is
marked, but pus is scant.
NOTE:
This contrasts with pus passed in cases of bacillary dysentery.
MD0152
2-12