Page 73 - Medical Parasitology_ A Textbook ( PDFDrive )

66 7 Coccidia

Pathogenesis and Clinical Features

Infection is through faecal oral route by ingestion of contaminated water and vege-
tables. Enterocytes show features of acute and chronic inflammation with blunting
and atrophy of villi and hyperplasia of crypts. It causes prolonged diarrhoea with
abdominal pain, low-grade fever and fatigue. The infection is more severe in immu-
nocompromised hosts, especially AIDS patients. Incubation period is 1–7 days.

Diagnosis

1. Microscopic examination
Direct wet mount to detect oocysts in faeces. Oocyst stains pink with Ziehl
Neelsen.

2. Biopsy
Histopathology examination of biopsied specimen from jejunum.

Treatment

Co-trimoxazole (160 mg trimethoprim/800 mg sulfamethoxazole twice/day for 7
days) is used for its treatment. Long term suppressive maintenance therapy is given
to HIV-infected patients.

Prevention and Control

1. Proper faecal disposal
2. Personal hygiene
3. Boiling of drinking water
4. Filtration of drinking water
5. Wash fruits and vegetables with clean water before eating
6. Health education

Sarcocystis

Distribution

It is worldwide in distribution. The 3 species that can infect humans are
Sarcocystis hominis (transmitted through cattle), Sarcocystis suihominis (trans-
mitted through pig) and Sarcocystis lindemanni (unknown mode of
transmission).