Cystoisosporiasis Flashcards
What is the other name for Isosporiasis?
Cystoisosporiasis
In which regions is Isosporiasis predominantly found?
Tropical and subtropical regions
Who is at increased risk for chronic, debilitating illness due to Isosporiasis?
Immunocompromised patients, including those who are HIV-infected
How do humans acquire infection from Isospora (Cystoisospora) belli?
By ingesting sporulated oocysts from contaminated food or water
What is the most common clinical manifestation of Isosporiasis?
Watery, non-bloody diarrhea
List some symptoms associated with Isosporiasis besides diarrhea.
- Abdominal pain
- Cramping
- Anorexia
- Nausea
- Vomiting
- Low-grade fever
What are potential complications of Isosporiasis in immunocompromised patients?
- Severe dehydration
- Electrolyte abnormalities (e.g., hypokalemia)
- Weight loss
- Malabsorption
How is Isosporiasis typically diagnosed?
By detecting Isospora oocysts in fecal specimens
What are the dimensions of Isospora oocysts?
23–36 µm by 12–17 µm
What diagnostic techniques can facilitate the detection of Isospora oocysts?
- Modified acid-fast techniques
- UV fluorescence microscopy
What is the primary method to prevent exposure to I. belli?
Avoiding potentially contaminated food or water
What chemoprophylaxis has been associated with lower incidence of Isosporiasis?
Trimethoprim-sulfamethoxazole (TMP-SMX)
What is the antimicrobial agent of choice for treating Isosporiasis?
TMP-SMX
What is the traditional treatment regimen for Isosporiasis?
10-day course of TMP-SMX (160/800 mg) administered orally four times daily
What should be considered if symptoms persist despite TMP-SMX therapy?
- Noncompliance
- Malabsorption
- Concurrent infections/enteropathies
What is the second-line agent for treating Isosporiasis?
Ciprofloxacin
What is recommended for patients with CD4 cell counts <200 cells/mm3 regarding prophylaxis?
Secondary prophylaxis with TMP-SMX
When can chronic maintenance therapy be discontinued?
When CD4 count >200 cells/mm3 for >6 months after ART initiation without active I. belli infection
What is the recommendation for pregnant women with symptomatic I. belli infection?
TMP-SMX therapy
What should be monitored in patients receiving TMP-SMX therapy?
- Clinical response
- Adverse events
True or False: Immune reconstitution with ART has been shown to result in fewer relapses of isosporiasis.
True
What is an alternative therapy for acute infection for patients with sulfa intolerance?
Pyrimethamine 50–75 mg PO daily + leucovorin 10–25 mg PO daily
What is the risk associated with the combination of pyrimethamine and sulfadoxine?
Increased risk of severe cutaneous reactions, including Stevens-Johnson syndrome
What should be done if a patient with Isosporiasis is not receiving ART?
Consider starting TMP-SMX therapy and ART simultaneously
What is the effect of TMP-SMX in the context of Pneumocystis pneumonia?
It provides indirect evidence of a protective effect against Isosporiasis
