Trichuris Trichiura. AUTHOR INFORMATION Section 1 of 9

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1 Febr (advertisement) Home Specialties CME PDA Contributor Recruitment Patient Education Articles Images CME Patient Education Advanced Search Li Back to: emedicine Specialties > Emergency Medicine > Infectious Diseases Trichuris Trichiura Last Updated: July 13, 2001 Rate this Article to a Colleague Synonyms and related keywords: whipworm, trichuriasis AUTHOR INFORMATION Section 1 of 9 Author: Eric L Weiss, MD, DTM&H, Director of Stanford Travel Medicine, Medical Director of Stanford Lifeflight, Assistant Professor, Departments of Emergency Medicine and Infectious Diseases, Stanford University School of Medicine Eric L Weiss, MD, DTM&H, is a member of the following medical societies: American College of Emergency Physicians, American College of Occupational and Environmental Medicine, American Medical Association, American Society of Tropical Medicine and Hygiene, Physicians for Social Responsibility, Southeastern Surgical Congress, Southern Association for Oncology, Southern Clinical Neurological Society, and Wilderness Medical Society Editor(s): Mark Louden, MD, FAAEM, Consulting Staff, Department of Emergency Medicine, Saint Francis Medical Center; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, Pharmacy, emedicine; Mark L Plaster, MD, JD, Editor-in-Chief of Emergency Physicians' Monthly, Department of Emergency Medicine, Memorial Hermann Hospital System; John Halamka, MD, Chief Information Officer, CareGroup Healthcare System, Assistant Professor of Medicine, Department of Emergency Medicine, Beth Israel Deaconess Medical Center; Assistant Professor of Medicine, Harvard Medical School; and Scott H Plantz, MD, FAAEM, Research Director, Assistant Professor, Department of Emergency Medicine, Mount Sinai School Quick Find Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Bibliography Click for related images. Related Articles Anemia, Chronic Gastroenteritis Giardiasis Continuing Education CME available for this topic. Click here to take this CME. Patient Education Click here for patient education.

2 of Medicine INTRODUCTION Section 2 of 9 Background: The whipworm, ie, Trichuris trichiura, is notable for its small size compared to Ascaris lumbricoides. Principally a problem in tropical Asia and, to a lesser degree, in Africa and South America, a lack of a tissue migration phase and a relative lack of symptoms characterize whipworm infection. Only patients with heavy infections become symptomatic. The worm derives its name from its characteristic whiplike shape; the adult (male mm, female mm) buries its thin, threadlike anterior half into the intestinal mucosa and feeds on tissue secretions, not blood. This relative tissue invasion causes occasional eosinophilia. The cecum and colon are the most commonly infected sites. Pathophysiology: After days in soil, eggs become infective. Soil-containing eggs must be swallowed, as with A lumbricoides, but in contrast to this parasite and to hookworm no tissue migratory phase occurs. Larvae hatch in the small intestine, where they grow and molt, finally taking up residence in the large intestine. The time from ingestion of eggs to development of mature worms is approximately 3 months. Adult females lay eggs for up to 5 years. Frequency: In the US: Whipworm infection is rare overall but is less rare in the rural Southeast, where 2.2 million people are infected. Internationally: Whipworm infection is common in less-developed countries; more than 500 million people are infected worldwide. Mortality/Morbidity: Whipworm infection is rarely fatal. Rectal prolapse may occur in heavily infected hosts. Race: No racial predilection exists. Sex: Boys are more likely to be infected because they are thought to eat more dirt than girls. Age: Children, due to a higher propensity to directly or

3 indirectly consume soil, are more commonly and more heavily infected. CLINICAL Section 3 of 9 History: Most patients are asymptomatic. Clinical symptoms are limited to patients with heavy infection, who tend to be small children or others who eat a lot of dirt. Note that there is no pulmonary migration and, thus, no pulmonary symptoms. Vague abdominal discomfort Diarrhea (often bloody, without fever) Rectal prolapse Failure to thrive Symptoms of anemia (massive infection only) Physical: Mild abdominal tenderness Signs of anemia Rectal prolapse Direct visualization of adult worms on rectal mucosa via anoscopy or if rectum is prolapsed (adult worms only in lower colon in heavy infection) Causes: Whipworm is caused by consumption of soil or food that has been fecally contaminated. (Eggs are infective or embryonated about 2-3 weeks after being deposited in the soil). DIFFERENTIALS Section 4 of 9 Anemia, Chronic Gastroenteritis Giardiasis

4 WORKUP Section 5 of 9 Lab Studies: Studies often reveal eosinophilia from ongoing tissue invasion (in contrast to all intestinal helminths except Strongyloides stercoralis). Rarely, studies show anemia. Characteristic eggs on stool smear (oval with transparent bipolar plugs) are visible. Each female produces eggs per day. (No stool concentration technique is necessary.) Other Tests: Obtain a stool smear for ova and parasites (as above). TREATMENT Section 6 of 9 Emergency Department Care: Effective anthelmintic therapy is available. Consultations: Specialty consultation is not necessary unless rectal prolapse or severe anemia is present; both are rare. MEDICATION Section 7 of 9 The list of drugs used to treat parasitic infections is large and varied. Treatment and disposition of parasites are based on the disease entity. Drug Category: Anthelmintic agents -- Parasite biochemical pathways are sufficiently different from the human host to allow selective interference by chemotherapeutic agents in relatively small doses. Drug Name Mebendazole (Vermox) -- Causes worm death by selectively and irreversibly blocking glucose uptake

5 Adult Dose Pediatric Dose and other nutrients in the susceptible adult intestine where helminths dwell. Administer a second course if patient is not cured within 3-4 wk. 100 mg PO bid on 3 consecutive d <2 years: Not established >2 years: Administer as in adults Contraindications Documented hypersensitivity Interactions Pregnancy Precautions Drug Name Adult Dose Pediatric Dose Carbamazepine and phenytoin may decrease effects; cimetidine may increase levels C - Safety for use during pregnancy has not been established. Adjust dose in hepatic impairment Albendazole (Albenza) -- Decreases whipworm ATP production, causing energy depletion, immobilization, and death. 400 mg/d PO in single dose; repeat in 3 wk if patient is not cured <2 years: 200 mg/d PO in a single dose; repeat in 3 wk if infestation persists >2 years: Administer as in adults Contraindications Documented hypersensitivity Interactions Pregnancy Precautions Carbamazepine may increase metabolism and decrease its efficacy; conversely, dexamethasone and praziquantel may increase plasma levels when coadministered C - Safety for use during pregnancy has not been established. Discontinue use if liver function tests increase significantly FOLLOW-UP Section 8 of 9 Further Inpatient Care: Inpatient care may be warranted for patients with rectal prolapse or severe anemia. Deterrence/Prevention: Household contacts are at low risk because of life-cycle requirements. If fecal contamination of soil is possible (eg, children defecating in the

6 back yard), consider the possibility of household transmission. Contacts may be screened for asymptomatic carrier state. Improved sanitation is the best way to eradicate T trichiura infection. Complications: Rectal prolapse or anemia may occur. Prognosis: Prognosis is excellent with proper treatment. Patient Education: Recommend good personal hygiene. BIBLIOGRAPHY Section 9 of 9 Bell DR: Soil transmitted helminths. In: Lecture Notes on Tropical Medicine. 4th ed. Blackwell Scientific Publications; 1985: Freedman DO: Intestinal nematodes. In: Gorbach SL, Bartlett JG, Blacklow NR, eds. Infectious Diseases. WB Saunders Co; 1992: Gilles HM: Intestinal nematode infections. In: Strickland GT, ed. Hunter s Tropical Medicine. WB Saunders Co; 1984: Jackson TF, Epstein SR, Gouws E: A comparison of mebendazole and albendazole in treating children with Trichuris trichiura infection in Durban, South Africa. S Afr Med J 1998; 88(7): [Medline]. Uga S, Nagnaen W, Chongsuvivatwong V: Contamination of soil with parasite eggs and oocysts in southern Thailand. Southeast Asian J Trop Med Public Health 1997; 28 Suppl 3: 14-7[Medline]. NOTE: Medicine is a constantly changing science and not all therapies are clearly established. New research changes drug and treatment therapies daily. The authors, editors, and publisher of this journal have used their best efforts to provide information that is up-to-date and accurate and is generally accepted within medical standards at the time of publication. However, as medical science is constantly changing and human error is always possible, the authors, editors, and publisher or any other party involved with the publication of this article do not warrant the information in this article is accurate or complete, nor are they responsible for omissions or errors in the article or for the results of using this information. The reader should confirm the information in this article from other sources prior to use. In particular, all drug doses, indications, and contraindications should be confirmed in the package insert. FULL DISCLAIMER Trichuris Trichiura excerpt Copyright 2004, emedicine.com, Inc. About Us Privacy Terms of Use Contact Us Advertise Institutional Subscribers