a family of 4 presented with complaints of recurrent attacks of diarrhea since the last one month with the present attack lasting since two days with severe abdominal cramps, tenesmus, anorexia and fatigue.
One 19 year old, complained of bloody mucoid stools altering with difficulty in defecation/constipation at times over the last one month.
On physical examination, they had mildly raised temperature, stable vitals and vague abdominal tenderness.
Complete blood picture and Stool examination were ordered for.
On the wet mount (of the stool sample) certain large ovoid cysts with central kidney shaped nuclear material were visualized.
On enquiring they consumed pork habitually and reared a few as a side line business.
The family was started on oral Metronidazole 750 mg, thrice daily for 10 days with oral rehydration advise after which they significantly improved.
Balantidium coli is a ciliated protozoan parasite inhabiting the large intestine of man, monkeys and pigs, feeding on the cell debris, starch granules and bacteria and living as a lumen parasite. It is the largest protozoan parasite measuring 40-60 micron metres or more making it easily visible in a stool preparation.
Mostly harmless
m/c clinical presentation: Chronic recurrent diarrhea alternating with constipation
Severe cases mimic intestinal amebiasis
Extra intestinal involvement: liver abscess, peritonitis, pleuritis & pneumonia
Lab diagnosis:
- Stool examination:
Easy to identify owing to it’s size
In acute cases: trophozoites are found in large numbers
In chronic/carriers: cysts are frequently identified
Trophozoites:
motile
oval in shape, with outer pellicle having linear striations and cilia
has 2 nucliei: 1 Macro nucleus and 1micro nucleus, 2 contactile vacuoles and numerous . food vacuoles
Microscopic appearance:
outer membrane with cilia
kidney shaped macronucleus
show rotatory boring movement on a wet mount preparation
stains yellow/brown with iodine with prominent macronucleus
Cysts:
double walled
mature cysts are immobile where the newly formed ones can exhibit limited motion.
has 2 nucleus, 2 contractile vacuoles
-
Biopsy: with H&E
(sigmoidoscope guided biopsy sample/scrapings of ulcers) -
Culture:
not done routinely to diagnose since stool examination and Histology are sufficient
can grow on any media that supports E.histolytica (refer #C11)
Treatment:
Tetracycline 500 mg qid x 10 days
or
Metronidazole 750 mg tid x 10 days
Preventive measures:
Hygienic rearing (of pigs)
Prevent human to pig contact
Preventive measures to avoid fecal contamination of food and water.
Thorough washing/ proper cooking
Hand hygiene
Treatment of human carriers or cyst shedders.