• one celled microscopic parasite that causes intestinal infection
  • fecal-oral transmission
  • endemic in tropical and subtropical regions


  • watery (sometimes explosive) diarrhea, loss of appetite, weight loss, [[abdominal pain/cramps, bloating, increased flatus, nausea, and fatigue
  • can last days to over a month
  • In immunocompromised hosts, cyclospora may cause severe, intractable, voluminous diarrhea resembling cryptosporidiosis. Extraintestinal disease in patients with AIDS may include cholecystitis and disseminated infection.


  • stool O&P
  • Detection is facilitated by staining stool samples with modified acid-fast stain or modified safranin stain. Multiple (≥ 3) stool specimens may be needed because cyst secretion may be intermittent (2)


  • Bactrim: 160mg TMP and 800mg SMX PO BID for 7 to 10 days for cyclosporiasis or for 10 days. Children are given 5mg/kg TMP and 25mg/kg SMX PO BID for the same number of days.
  • Immunocompromised patients may require higher doses and longer duration of treatment, and treatment of acute infection is usually followed by long-term suppressive therapy