Cyclospora Infection (Cyclosporiasis) Follow-up

Updated: Jul 16, 2021
  • Author: Chinelo N Animalu, MD, MPH, FIDSA; Chief Editor: Pranatharthi Haran Chandrasekar, MBBS, MD  more...
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Further Outpatient Care

Administer a complete course of oral antibiotics.

Follow up 1 week after discharge to verify continuing clinical improvement.


Further Inpatient Care

Assess patients for response to rehydration and antibiotic therapy.

Discharge to outpatient management when patients demonstrate clinical improvement and can tolerate oral intake and oral medication.


Inpatient & Outpatient Medications

TMP-SMZ is the drug of choice. It is usually administered orally but can be administered intravenously if the patient cannot tolerate peroral medications because of nausea, vomiting, or underlying gastrointestinal problems.

Ciprofloxacin has been used as an alternative if the patient has an allergy to TMP-SMZ, but the response may not be as favorable.



The risk of acquiring Cyclospora infection can be reduced significantly (but not eliminated), particularly in developing countries, by adhering to health guidelines, including the following:

  • Wash hands with soap and water before to and after handling food. Wash non-food items (eg, cutting board, countertop) with hot soap and water between preparation of raw animal products and fruits.

  • Drink only purified water. In developing countries, tap water is considered unpurified. Consume only bottled water known to be safe.

  • Purify water either by boiling (bringing to a boil is sufficient) or iodination or chlorination (as with Cryptosporidium, whether effective commercial products are available for use by the traveler appears to be controversial).

  • Wash fresh fruits with purified water and peel them after washing hands with soap and purified water. Wash fresh vegetables with purified water and prepare them after washing hands with soap and water. As a caveat, one study suggests that only washing vegetables and fruit that cannot be peeled may not remove Cryptosporidium and Cyclospora completely. [39]

  • Raspberries and similar fruits eaten in developing countries and imported from developing countries are a particular risk for Cyclospora contamination because they cannot be decontaminated easily, even with an iodine wash solution.

  • For any fruit or vegetable that was cut or cooked and not in use for the current dish, refrigerate within 2 hours, making sure to do so away from raw animal products.

  • For people with kitchen gardens, ensure it is safe from dogs, cats, and wild animals. [40]



Several complications have been reported as case reports and are detailed below.

Guillain-Barré syndrome (GBS)

One week after the onset of Cyclospora infection secondary to Guatemalan raspberries, a 58-year-old man developed GBS (confirmed by nerve conduction study), initially manifested as generalized weakness and altered sensation in the hands and feet; within 18 hours he was quadriparetic, areflexic, and had to be mechanically ventilated. He responded to therapy for the GBS (plasmapheresis, intravenous immunoglobulin), but, at 2 months after hospital discharge, he still had significant bilateral hand weakness, although he could jog 50 yards.

Acalculous cholecystitis

Cyclospora trophozoites, merozoites, and oocysts demonstrated in gallbladder epithelium after resection. A 35 year-old man with history of HIV (CD4-11; noncompliant) developed Cyclospora infection and 5 days later developed acute right upper quadrant pain. He was admitted on day 10 of his illness. Because he was allergic to TMP-SMZ, he was treated with levofloxacin. On day 13 of his illness, he underwent a laparoscopic cholecystectomy. Pathology revealed acute and chronic cholecystitis and Cyclospora. Two weeks after surgery, his stool was negative for ova and parasites. [41]

A 28 year-old man who had diarrhea for 6 months and a 46-year-old man who had diarrhea for 10 days, both with HIV, both treated with TMP-SMZ, developed right upper quadrant abdominal pain and elevated alkaline phosphatase levels. Gallbladder ultrasound demonstrated wall thickening in both patients. After TMP-SMZ treatment, symptoms resolved, alkaline phosphatase levels returned to normal, Cyclospora oocysts ceased to be excreted, and the ultrasound findings returned to normal. These findings suggest, but do not prove, Cyclospora -related reversible gallbladder pathology.

Reactive arthritis syndrome (RAS)

RAS developed in a 31-year-old man with documented Cyclospora infection 5 months after the exposing event and approximately 2 months after the absence of Cyclospora on intestinal biopsies. He had not received TMP-SMZ because of sulfa allergy, and no other antibiotic was prescribed. At the time of the RAS diagnosis (dysuria, negative urinalysis, eye pain, documented iritis, arthralgias, right buccal painful ulcer), serology was negative for Lyme disease and chlamydia; HLA testing was negative for HLA-B27; and stools were negative for parasites. He responded dramatically to oral steroids and doxycycline.

One study suggested that Cyclospora in the gut disrupts the natural microbiome and could increases risk for T1DM and Celiac disease.  [42]

Pulmonary conditions

Cyclospora has been isolated from the sputum of two patients: one with active tuberculosis and the other with weight loss, cough, and purulent sputum. Its role as a pulmonary pathogen is not clear.

Biliary disease 

This condition has been reported in association with cyclosporiasis.



In immunocompetent patients, the prognosis is excellent.

In immunocompromised patients with HIV, diarrhea may last several months. After resolution, patients require prophylactic TMP-SMZ 3 times a week to prevent reinfection.


Patient Education

All travelers to developing countries should follow the food and water precautions outlined in Deterrence/Prevention.

Raspberries imported from developing countries may be contaminated with Cyclospora. Because of the nature of this berry, decontaminating with running water or the use of an iodine wash solution is considered very difficult, if not impossible. Anyone who is immunocompromised should be aware of the possibility of developing cyclosporiasis as a result of eating raspberries imported from developing countries.