eMedicine Specialties > Pediatrics: General Medicine > Parasitology
Isosporiasis: Differential Diagnoses & Workup
Updated: Jan 22, 2009
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
Differential Diagnoses
Other Problems to Be Considered
Aeromonas infection
Clostridium difficile infection
Celiac disease
Kaposi sarcoma
Lymphoma
Microsporidiosis
Sarcocystis infection
Workup
Laboratory Studies
- Stool examination for ova and parasites is the test of choice for isosporiasis.
- Mature oocysts measure 30 X 12 µm and have a thin translucent wall and 2 round sporocysts, each of which has 4 crescentic sporozoites.
- Auramine-rhodamine fluorescent, modified Kinyoun acid-fast, hematoxylin/eosin, Giemsa, and/or carbol fuchsin staining may be helpful in identifying the translucent oocysts.
- Oocysts autofluoresce under ultraviolet epifluorescence illumination using a 450- to 490-nm excitation filter.
- Charcot-Leyden crystals and high fat content are often observed.
- CBC count may reveal mild peripheral eosinophilia in one half of patients.
- Serologic testing is not available.
- Electron microscopy may be helpful, but it is labor intensive and lacks specificity.
Imaging Studies
Double contrast barium upper GI series with small-bowel follow-through may be helpful.
- The severity of radiographic findings seems to depend on duration of illness and to correlate with the degree of villous atrophy noted on biopsy findings.
- Short-term disease (<1 y) seems to result in minimal or irregular thickening of mucosal folds.
- Long-term disease seems to correlate with markedly granular mucosal appearance with effacement of the folds.
Other Tests
- The Entero-Test (swallowed string test to provide a duodenal sample) may yield a positive specimen, if stool study results are negative.
Procedures
Upper GI endoscopy may provide useful specimens for examination, if the following test results are negative:
- Duodenal aspirate for ova and parasite examination
- Small bowel biopsy for histopathology
Histologic Findings
- Histologic findings appear to correlate with the severity of the symptoms observed. Focal-to-widespread mucosal changes are associated with severe symptoms.
- In mild cases, the only findings may range from flattened villi to mild, nonspecific alterations and increased inflammatory cells in the lamina propria.
More on Isosporiasis |
| Overview: Isosporiasis |
 Differential Diagnoses & Workup: Isosporiasis |
| Treatment & Medication: Isosporiasis |
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References
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Further Reading
Keywords
isosporiasis, Apicomplexa coccidia protozoan, dehydration, diarrhea, foul-smelling flatus, gastrointestinal infection, GI infection, Isospora, Isospora belli, I belli, I belli disease, I belli infection, parasitic infection, steatorrhea
