Definition
A.Cyclosporiasis is a one-cell parasite that infects the upper small intestines. Causes of cyclosporiasis include consuming infected water or produce (fresh fruits, especially raspberries and vegetables) or exposure to the organism during travel to countries where it is endemic.
B.It manifests as protracted and relapsing gastroenteritis. The clinical syndrome consists of explosive watery diarrhea, nausea, anorexia, weight loss, fatigue, and abdominal cramps that may persist for 7 days to several weeks, with a waxing and waning course.
C.In an immunocompromised host, onset is insidious, and the condition becomes chronic; the shedding of oocysts continues indefinitely. Symptoms associated with cyclosporiasis are more severe in HIV/AIDS patients.
D.The oocysts are resistant to most disinfectants used in food and water processing and can remain viable for prolonged periods.
Incidence
A.Cyclosporiasis affects approximately 16,000 persons per year in the United States among 76 million cases of food-borne diarrhea. It is endemic in other regions of the world.
B.Most outbreaks in the United States and Canada have been associated with consumption of imported fresh produce. Most cases are diagnosed between May and August. Reported cases increased between summer 2016 and summer 2017.
C.It affects all ages.
D.In the United States, one-third of cases occur in international travelers, one-third of cases are acquired without travel, and one-third occur without known risk factors.
E.The highest incidences are in Guatemala and Peru, with other countries in Central America, South Americana, Asia, and the Caribbean also contributing to reported cases among travelers.
Pathogenesis
A.Infection is caused by an 8- to 10-μm spore-forming coccidian protozoan called Cyclospora cayetanensis. Transmission of oocysts is by the oral-fecal route. The incubation period ranges from 2 days to 2 weeks after excretion, depending on temperature and humidity.
Predisposing Factors
A.Incompetent or compromised immune system (e.g., infection with HIV).
B.Travel to underdeveloped or tropical countries.
C.Ingestion of contaminated food or water.
D.Contact with animals that carry the parasite.
Common Complaints
A.Abrupt, profuse, malodorous, watery diarrhea.
B.Nausea.
C.Vomiting.
D.Anorexia.
E.Substantial weight loss.
F.Flulike symptoms.
G.Abdominal cramps and bloating.
Other Signs and Symptoms
A.Asymptomatic—common among individuals residing in endemic regions.
B.Low-grade fever.
C.Nausea and vomiting.
D.Profound fatigue.
E.Yellow-to-khaki-green stools.
F.Flatus.
G.Dehydration.
Subjective Data
A.Review onset, duration, and course of symptoms. Is diarrhea acute or chronic?
B.Question the patient about travel to areas known for cyclospora, such as Guatemala, Haiti, Puerto Rico, Pakistan, India, Mexico, Nepal, New Guinea, and Peru.
C.Review the patient’s intake of medications and other substances that can cause diarrhea, especially antibiotics, laxatives, quinidine, magnesium-containing antacids, digitalis, loop diuretics, antihypertensives, alcohol, caffeine, herbal teas, and sorbitol-containing (sugar-free) gum and mints.
D.Ask about the nature of the patient’s bowel movements (BMs), including frequency, consistency, volume, and presence of blood, pus, or mucus.
E.Review associated symptoms that need evaluation: fever, abdominal pain, and anorexia.
F.Ask the patient if other family members or sexual contacts are also ill.
G.Establish the patient’s normal weight and any recent weight loss. How much weight was lost and over what period of time?
Physical Examination
A.Check temperature, pulse, respirations, blood pressure (BP) (vital signs are normal in most cases), height and weight to calculate body mass index (BMI).
B.Inspect:
1.Inspect general appearance for signs of illness and dehydration:
a.Inspect mucous membranes.
b.Note the presence of decreased skin turgor.
C.Auscultate the abdomen for bowel sounds in all quadrants.
D.Palpate:
1.Palpate the abdomen for masses, rebound tenderness, guarding; may exhibit right upper quadrant (RUQ) pain (biliary disease).
2.Palpate lymph nodes for enlargement.
E.Perform rectal exam.
Diagnostic Tests
Identification may be made by microscopic examination of a stool preparation by modified acid-fast staining, fluorescence microscopy, or review of wet mounts of stool by experienced microscopists. Finding large numbers of white cells suggests an inflammatory or invasive diarrhea. The following tests are done:
A.Acid-fast Ziehl–Neelsen stained slide of stool—8 to 10 micron cyclospora oocysts are visible.
B.Stool culture for ova and parasites: Parasites are passed intermittently, so three or more stools on alternating days should be examined. Specific requests to assess for cyclospora is necessary.
C.Endoscopy with small bowel biopsy.
Differential Diagnoses
A.Cyclospora infection.
B.Giardiasis.
C.Malabsorption.
D.Escherichia coli infection: E. coli causes diarrhea within hours of ingesting contaminated food. Confirm by checking if others were affected.
E.Irritable bowel syndrome (IBS): Leukocyte-free mucus is the hallmark of IBS.
F.Viral diarrhea.
G.Lactose intolerance.
H.Other bacterial infections, for example, Shigella, Salmonella, and Campylobacter.
I.Cholera.
J.Inflammatory bowel disease (IBD; Crohn’s disease (CD) or ulcerative colitis [UC]).
K.Cryptosporidium—retain acid-fast stain but are smaller, only 5 microns.
Plan
A.General interventions:
1.Advise the patient to tell household members and sexual contacts to seek medical examination and treatment.
2.Children and caregivers with diarrhea should be excluded from child care centers until they become asymptomatic.
3.Fresh produce should always be washed thoroughly before it is eaten.
B. 
See Section III: Patient Teaching Guide Diarrhea
:
1.Discuss safe sexual practices.
2.Teach contact precautions to those caring for diapered and/or incontinent children.
C.Dietary management:
1.Tell the patient to increase fluids. Fluid replacement is the basic approach to prevent dehydration from diarrhea.
2.Tell the patient to restrict milk products to rule out lactose intolerance.
3.Give the patient a copy of a diet to control nausea and vomiting. See Appendix B for Nausea and Vomiting Diet Suggestions.
D.Pharmaceutical therapy:
1.The drug of choice is trimethoprim-sulfamethoxazole (TMP-SMZ). It can reduce shedding, and stop diarrhea within 2 days:
a.Adults:
i.Immunocompetent host: TMP 160 mg/SMZ 800 mg tablet orally twice a day for 7 to 10 days.
ii.Immunocompromised host: TMP 160 mg/SMZ 800 mg tablet orally four times a day for 10 days, followed by prophylaxis with TMP 160 mg/SMZ 800 mg orally three times per week.
2.For sulfa allergic patients: Nitazoxanide (500 mg twice daily for 7 days)
3.Ciprofloxacin (Cipro). Treatment failures have been reported:
a.Adults: Cipro 500 mg orally twice a day for 7 to 10 days for acute infection.
b.Adults: Prophylaxis in HIV: Cipro 500 mg orally three times a week.
Follow-Up
A.See the patient in 1 week to verify continuing clinical improvement.
B.If diarrhea persists 2 weeks or more, a second evaluation is indicated.
C.Report cases of cyclosporiasis to the health department.
Consultation/Referral
A.Consult an infectious disease specialist and/or gastroenterologist if the patient has no symptom relief after completing therapies or has a prolonged or severe case.
Individual Considerations
A.Pregnancy:
1.TMP-SMZ is a pregnancy category C drug. Use during pregnancy if the potential benefit outweighs the risk to the fetus.
2.TMP-SMZ should be avoided near term because of the potential for hyperbilirubinemia and kernicterus in the newborn.
B.Geriatrics:
1.Due to polypharmacy a full review of medications, herbals, and over-the-counter (OTC) drugs should be undertaken to identify medications that should be avoided in the geriatric population, duplicate medications, and medications that are able to be to be decreased or deprescribed. (Refer to section Deprescribing
of Chapter 3.)
2.For the older adult with existing diarrhea, nurse practitioner (NPs) should practice special consideration of the following geriatric syndromes:
a.Falls:
i.Consistently assess for falls. Discuss the risk of dizziness or lightheadedness when standing orthostatic hypotension and due to weakness.
ii.Many falls occur en route to the bathroom when the patient hurries and may not be able to remove their pants and undergarments in time.
iii.At the minimum, older adults should be asked how many times they have fallen since their last visit. A reported fall should trigger questions about whether the fall led to injury, a visit to urgent care or hospital ED, or a hospital admission.
iv.Safety measures to reduce falls in the home include removing small area carpets, keeping night lights along the path to the bathroom, and installing a raised toilet seat or nearby grab bars.
v.Durable medical equipment such as a bedside commode may be considered.
vi.Patients who use pads or adult diapers should be informed of risks associated with infrequent changing. Because of the high cost of absorbent pads and undergarments, infrequent changing is common and contact dermatitis and candidal rashes may develop. If these occur, patients should be encouraged to change pads/garments more frequently, and avoid wearing absorbent garments overnight and instead use mattress/bedding pads.
b.Delirium is a common early sign of dehydration, acute illness, or infection in the elderly. It is more common in patients with existing cognitive impairment. Dehydration is more common in the elderly. Signs of dehydration include confusion, muscle weakness, fever, dizziness, poor skin turgor, hypotension, and tachycardia:
i.At a minimum, patients and family should be asked if they have experienced episodes of altered mental status since their last visit.
ii.The Brief Confusion Assessment Method (bCAM) is a well-documented assessment for delirium. It is available at www.mnhospitals.org/Portals/0/Documents/ptsafety/LEAPT%20Delirium/HELP%20Program%20CAM%20Flowsheet.pdf.
c.Weight loss/appetite suppression—weight loss is a predictor of mortality. Clinically significant weight loss is considered to be 5% loss of usual body weight in 3 months or 10% in 6 months:
i.Monitor weight patterns/BMI. (Caution: BMI is not used to identify loss of muscle mass.)
ii.Monitor both serum albumin and anemia: Hypoalbuminemia and anemia is not necessarily associated with low bodyweight. It can be caused by decreases in liver protein synthesis:
•Serum albumin concentration is commonly recommended.
•Hemoglobin (Hgb), prealbumin, and transferrin.
•Cholesterol.