Introduction Isospora belli History of Discovery Transmission Clinical Presentation Treatment Web Links References

Diagnostic Tests

Mature oocyst under bright field microscope (2)

Developing oocyst with acid-fast stain (6)

Stool examinations (5):

Bright field microscopy

Differential interference contrast

UV fluorescence microscopy

Acid-fast stain

Blood count may indicate mild eosinophelia


Drug treatment involves primarily a combination of the antibiotics, sulfamethoxazole and trimethoprim, but alternative drugs are also effective. In immunocompetent individuals, the symptoms disappear in 2-3 days with treatment and longer without treatment. In either case, the illness disappears completely. Side effects of antibiotic treatment are uncommon and generally mild. They include sore throat, skin rash, and, the most severe, anemia due to folic acid deficiency. (5)

In immunocompromised patients, symptoms will disappear after a few days but the illness may return after as little as 2 months (5).

Control and Prevention

The most effective means of prevention is improved sanitation standards and practices. Increased awareness and attention should be given in areas of higher Isosporiasis occurence and with immunocompromised patients (5).