Microsporidium

• Unicellular spore-forming parasitic protozoa that are found pervasively throughout the environment.[1] Microsporidiosis most commonly affects immunosuppressed individuals and seldom has implications for the immunocompetent patient.

Clinical manifestations are wide ranging and typically affect immunosuppressed hosts (e.g. HIV/AIDS, long-term steroid use, transplant and chemotherapy patients), travelers, children, and the elderly[2]. The most common manifestation is copious diarrhea with volume depletion leading to electrolyte derangements.[3]

• Microsporidiosis
• Cryptosporidiosis
• CMV (CD4 < 100)
• MAC (CD4 < 100)
• Adenovirus
• Isospora
• Giardia
• E. coli
• C. difficile

• Initial treatment consists of the ABCs
  • IV fluid resuscitation with LR or NS
  • Oral rehydrating solution for mild dehydration and tolerating PO intake
  • Address electrolyte derangements
• Albendazole 400 mg PO bid for 14-28 days in adults (15mg/kg PO bid for 7 days in children)
• Ondansetron or promethazine for nausea (avoid metoclopramide due to pro-motility effects)
• Loperamide for symptom reduction (contraindicated with bloody stool)

• Discharge: immunocompetent or low risk patients with unclear etiology but normal examination findings after rehydration
• Admission: patients with life-threatening volume loss, failure to improve after resuscitation, electrolyte abnormalities requiring gradual and/or significant correction, toxic or ill-appearing, intolerant of PO intake or significant risk factors (CD4 < 100, chemotherapy, transplant, etc.)
• Pearl: Obtain contact information for patients PCP and specialist providers (oncology, infectious disease, rheumatology, etc). Consultation and coordination of care is especially important for patients with significant and relevant co-morbidities

• CDC-Microsporidiosis