eMedicine Specialties > Pediatrics: General Medicine > Parasitology

Whipworm

Robert W Tolan Jr, MD, Chief, Division of Allergy, Immunology and Infectious Diseases, The Children's Hospital at Saint Peter's University Hospital; Clinical Associate Professor of Pediatrics, Drexel University College of Medicine
Tina Slusher, MD, Assistant Professor, Department of Pediatrics, Section of Pediatric Critical Care, West Virginia University; Steven L Lanski, MD, Department of Pediatrics, Division of Pediatric Emergency Medicine, Assistant Professor, Emory University and Children's Healthcare of Atlanta at Egleston

Updated: Jan 27, 2009

Introduction

Background

Trichuris trichiura (whipworm) is a roundworm of the phylum Nematoda. It is one of the most common human parasites. The common name is derived from the worm's distinctive whiplike shape. The adult worm usually reaches 3-5 cm in length and has a lifespan of 1-3 years.

Pathophysiology

Humans are the only known host of T trichiura. The organism is spread via the fecal-oral route. Potential hosts ingest the embryonated (mature) eggs. The eggs hatch in the small intestine, and the larvae attach to and penetrate the small intestinal mucosa, where they begin to mature. After approximately one week, the immature worms move passively to the large intestine and proximal colon. The worms' anterior portions penetrate the mucosal epithelium and the worms can imbed over one half of their length into the mucosal surface.

Once the worms are sexually mature, mating begins. Egg production occurs 2-3 months after initial ingestion. The female worm is capable of producing 3,000-20,000 eggs a day. Once the eggs are passed in the feces, they develop in a warm humid environment. Egg maturation occurs in approximately 2-6 weeks. The embryonated egg can maintain viability for several months under suitable conditions. Destruction occurs with exposure to direct sunlight for more than 12 hours and to temperatures of less than -8°C or higher than 40°C for one hour.

Frequency

United States

Prevalence of whipworm infestation is less than 0.1%. The most common areas of infection are the southern Appalachian range and Gulf coast states.¹

International

Whipworm infections are among the most common of all human parasites, with an estimated 750-800 million infections worldwide. The most affected regions are rural areas with poor sanitation and tropical climates, including Southeast Asia, Africa, the Caribbean, and Central and South America. Prevalence rates are as high as 80% in these regions. In contrast, prevalence in areas of Western Europe and Japan is similar to that in the United States.

Mortality/Morbidity

Most infections are asymptomatic. Symptoms are related to the worm load or number of worms involved in an infection. Heavy infections (hundreds to thousands of worms) can lead to death secondary to GI and hematologic complications.

Age

Although infections are observed in all age groups, most heavy infections are observed in the pediatric population. This probably reflects the increased likelihood of children to have poor hygiene and to play in soil that carries the worms' mature eggs.

Clinical

History

• When evaluating a patient suspected of having a whipworm infection, the most important part of the history is travel to or living in an area of known infestation.
• GI complaints associated with these infections are diverse. Long-term GI complaints with associated exposure suggest whipworm infection.
• Most infections are asymptomatic. Patients with fewer than 100 worms are frequently asymptomatic; however, they may present with lower abdominal discomfort, flatulence, and diarrhea or constipation.
• Patients with heavy infection have hundreds to thousands of worms and may present with lower or epigastric pain, vomiting, abdominal distension, anorexia, weight loss, anemia, diarrhea, tenesmus (painful straining), and rectal prolapse. Trichuris dysentery syndrome is observed in heavy infections and characterized by bloody mucoid diarrhea, small frequent stools, tenesmus, anemia, and growth retardation.
• Polyparasitic infections can occur with whipworms, ascaris, and hookworms because these parasites live in similar environments.²

Physical

• Generally, physical examination findings are normal.
• Each worm causes an estimated 5 µL of blood loss every day.
• Heavy infections are required to cause anemia.
• Prolonged infections are reported to lead to growth failure, intellectual delays, and digital clubbing; however, growth and intellectual delays are likely to be multifactorial.

Causes

• The organism is spread via the fecal-oral route. Potential hosts ingest the embryonated (mature) eggs.
• Most heavy infections are observed in the pediatric population because children are more likely to have poor hygiene and to play in soil that carries the worms' mature eggs.

Differential Diagnoses

Other Problems to Be Considered

GI bleeding
Intestinal duplications
Milk protein allergy
Eosinophilic colitis
Neglect
Malignancy
Atopy
Copper deficiency
Pediatrics, Rotavirus
Clostridium Difficile Colitis

Workup

Laboratory Studies

• Diagnosis is usually established by means of microscopic examination of stool.
  • Whipworm eggs have a characteristic barrel (American football) shape with translucent polar plugs.
  • The stool commonly contains RBCs and WBCs, including eosinophils/Charcot-Leyden crystals.
• Perform a CBC count. Eosinophilia is uncommon; however, when present, it ranges from 5-20%.

Procedures

• Anoscopy may be useful. In heavy infections, worms can be directly visualized.

Treatment

Medical Care

Infections are treated with broad-spectrum anthelminthic agents. Most infections can be treated successfully with mebendazole. Retreatment is occasionally necessary if symptoms persist longer than 2 weeks after initial treatment.

Consultations

Consultations with the following specialists may be appropriate:

• Infectious diseases specialist
• Gastroenterologist 
• Hematologist

Medication

Anthelmintics

Parasite biochemical pathways are different from the human host; thus, toxicity is directed to the parasite, egg, or larvae. Mebendazole is the treatment of choice for trichuriasis. Albendazole is an alternative medication that can be used.³ Both are broad-spectrum anthelminthic agents. These drugs interfere with the organism's microtubule formation. Recently, nitazoxanide has been studied as a possible treatment option.^4,5,6

Mebendazole (Vermox)

The treatment of choice for whipworm infections. Causes worm death by selectively and irreversibly blocking uptake of glucose and other nutrients in adult intestine where helminths dwell.

Dosing

Adult

100 mg PO bid for 3 d or 500 mg PO once

Pediatric

<2 years: Not established
>2 years: Administer as in adults

Interactions

Carbamazepine and phenytoin may decrease effects of mebendazole; cimetidine may increase mebendazole levels

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Adjust dose in hepatic impairment; use caution when breastfeeding because extent of drug excretion is not known; use caution in patients <2 y because limited data exist

Albendazole (Albenza)

Decreases ATP production in worms, causing energy depletion, immobilization, and, finally, death. Considered investigational for use in treating this condition.

Dosing

Adult

400 mg PO as a single dose for 1 d, 3-d treatment often required for heavy infestations; may repeat in 3 wk prn

Pediatric

<2 years: 200 mg PO qd for 3 d; repeat in 3 wk prn
>2 years: Administer as in adults

Interactions

Coadministration with carbamazepine may decrease efficacy; dexamethasone, cimetidine, and praziquantel may increase toxicity; abdominal pain, nausea, vomiting, diarrhea, dizziness, vertigo, fever, increased intracranial pressure, and alopecia may occur

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Discontinue use if serum transaminases increase significantly (resume when levels decrease to pretreatment values)

Nitazoxanide (Alinia)

Inhibits growth of Cryptosporidium parvum sporozoites and oocysts and Giardia lamblia trophozoites. Elicits antiprotozoal activity by interfering with pyruvate-ferredoxin oxidoreductase (PFOR) enzyme-dependent electron transfer reaction, which is essential to anaerobic energy metabolism. Available as a 20-mg/mL oral susp. May have activity in trichuriasis.

Dosing

Adult

500 mg PO bid for 3 d

Pediatric

<1 year: Not established
1-3 years: 100 mg (5 mL) PO q12h for 3 d with food
4-11 years: 200 mg (10 mL) PO q12h for 3 d with food
>11 years: Administer as in adults

Interactions

Tizoxanide (nitazoxanide metabolite) is >99.9% bound to plasma protein and may potentially increase toxicity of other highly plasma protein-bound drugs

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

May cause abdominal pain, diarrhea, vomiting, or headache; administer with food; caution when coadministered with other highly plasma protein-bound drugs with narrow therapeutic indices

Follow-up

Further Outpatient Care

• Retreatment may be necessary if symptoms persist 2-3 weeks after initial therapy.

Deterrence/Prevention

• Limiting the morbidity associated with this disease centers around improved sanitation for areas with heavy infestation.
• Some clinicians have suggested periodic deworming programs for children in endemic areas.

Complications

• Rectal prolapse, dysentery, anemia, malnutrition, and growth retardation all can complicate heavy infections.

Prognosis

• With treatment, prognosis is typically excellent.

Patient Education

• Emphasize good hygiene and avoidance of pica.

Miscellaneous

Medicolegal Pitfalls

• Failure to recognize the most severe infections as parasitic is a pitfall. Resultant delay in antiparasitic treatment can lead to morbidity associated with blood loss, malnutrition, and electrolyte imbalances.

References

1. Kappus KK, Juranek DD, Roberts JM. Results of testing for intestinal parasites by state diagnostic laboratories, United States, 1987. MMWR CDC Surveill Summ. Dec 1991;40(4):25-45. [Medline].

2. Bethony J, Brooker S, Albonico M, Geiger SM, Loukas A, Diemert D. Soil-transmitted helminth infections: ascariasis, trichuriasis, and hookworm. Lancet. May 6 2006;367(9521):1521-32. [Medline].

3. Nascimento-Carvalho CM, de Fatima Gesteira M, Azul-Neto LS, Andrade MQ. Prolonged treatment with albendazole for massive trichuriasis infection. Pediatr Infect Dis J. Nov 2004;23(11):1070. [Medline].

4. Diaz E, Mondragon J, Ramirez E, Bernal R. Epidemiology and control of intestinal parasites with nitazoxanide in children in Mexico. Am J Trop Med Hyg. Apr 2003;68(4):384-5. [Medline]. [Full Text].

5. Gilles HM, Hoffman PS. Treatment of intestinal parasitic infections: a review of nitazoxanide. Trends Parasitol. Mar 2002;18(3):95-7. [Medline].

6. Pearson RD. Nitazoxanide As Treatment of Intestinal Parasites in Children. Curr Infect Dis Rep. Feb 2004;6(1):25-26. [Medline].

7. AAP. Trichuriasis (Whipworm infection). In: 2006 Red Book: Report of the Committee on Infectious Diseases. 27^th ed. Elk Grove Village, Ill: American Academy of Pediatrics; 2006:674-5.

8. Arruda LK, Santos AB. Immunologic responses to common antigens in helminthic infections and allergic disease. Curr Opin Allergy Clin Immunol. Oct 2005;5(5):399-402. [Medline].

9. Cooper PJ. Interactions between helminth parasites and allergy. Curr Opin Allergy Clin Immunol. Feb 2009;9(1):29-37. [Medline].

10. da Costa e Silva EJ, de Albuquerque SC. Trichuris trichiura. Pediatr Radiol. Feb 2007;37(2):239. [Medline].

11. Elliott DE, Summers RW, Weinstock JV. Helminths and the modulation of mucosal inflammation. Curr Opin Gastroenterol. Jan 2005;21(1):51-8. [Medline].

12. Ezeamama AE, Friedman JF, Acosta LP, et al. Helminth infection and cognitive impairment among Filipino children. Am J Trop Med Hyg. May 2005;72(5):540-8. [Medline]. [Full Text].

13. Eziefula AC, Brown M. Intestinal nematodes: disease burden, deworming and the potential importance of co-infection. Curr Opin Infect Dis. Oct 2008;21(5):516-22. [Medline].

14. Falcone FH, Pritchard DI. Parasite role reversal: worms on trial. Trends Parasitol. Apr 2005;21(4):157-60. [Medline].

15. Flisser A, Valdespino JL, Garcia-Garcia L, et al. Using national health weeks to deliver deworming to children: lessons from Mexico. J Epidemiol Community Health. Apr 2008;62(4):314-7. [Medline].

16. Fox LM, Furness BW, Haser JK, et al. Tolerance and efficacy of combined diethylcarbamazine and albendazole for treatment of Wuchereria bancrofti and intestinal helminth infections in Haitian children. Am J Trop Med Hyg. Jul 2005;73(1):115-21. [Medline]. [Full Text].

17. Goodman D, Haji HJ, Bickle QD, et al. A comparison of methods for detecting the eggs of Ascaris, Trichuris, and hookworm in infant stool, and the epidemiology of infection in Zanzibari infants. Am J Trop Med Hyg. Apr 2007;76(4):725-31. [Medline].

18. Grencis RK, Cooper ES. Enterobius, trichuris, capillaria, and hookworm including ancylostoma caninum. Gastroenterol Clin North Am. Sep 1996;25(3):579-97. [Medline].

19. Hall A, Hewitt G, Tuffrey V, de Silva N. A review and meta-analysis of the impact of intestinal worms on child growth and nutrition. Matern Child Nutr. Apr 2008;4 Suppl 1:118-236. [Medline].

20. Hamer D, Despommier D. Intestinal nematodes. In: Gorbach SL, Bartlett JG, Blacklow NR, eds. Infectious Diseases. 2^nd ed. Philadelphia, Pa: WB Saunders Co; 1998:2003-5.

21. Hotez PJ, Arora S, Bethony J, et al. Helminth infections of children: prospects for control. Adv Exp Med Biol. 2005;568:135-44. [Medline].

22. Hutchinson SE, Powell CA, Walker SP, et al. Nutrition, anaemia, geohelminth infection and school achievement in rural Jamaican primary school children. Eur J Clin Nutr. Nov 1997;51(11):729-35. [Medline].

23. [Best Evidence] Keiser J, Utzinger J. Efficacy of current drugs against soil-transmitted helminth infections: systematic review and meta-analysis. JAMA. Apr 23 2008;299(16):1937-48. [Medline].

24. Lorenzetti R, Campo SM, Stella F, et al. An unusual endoscopic finding: Trichuris trichiura. Case report and review of the literature. Dig Liver Dis. Nov 2003;35(11):811-3. [Medline].

25. Markell EK. Intestinal nematode infections. Pediatr Clin North Am. Aug 1985;32(4):971-86. [Medline].

26. Medical Economics Company. Physicians' Desk Reference. 53^rd ed. Montvale, NJ: Medical Economics Co; 1999:1442, 3018.

27. Mukhopadhyay C, Wilson G, Chawla K, Vs B, Shivananda PG. A 6 year Geohelminth infection profile of children at high altitude in Western Nepal. BMC Public Health. Mar 27 2008;8:98. [Medline].

28. Quihui L, Valencia ME, Crompton DW, et al. Role of the employment status and education of mothers in the prevalence of intestinal parasitic infections in Mexican rural schoolchildren. BMC Public Health. 2006;6:225. [Medline]. [Full Text].

29. Reddy M, Gill SS, Kalkar SR, et al. Oral drug therapy for multiple neglected tropical diseases: a systematic review. JAMA. Oct 24 2007;298(16):1911-24. [Medline].

30. Stoltzfus RJ, Albonico M, Tielsch JM, et al. School-based deworming program yields small improvement in growth of Zanzibari school children after one year. J Nutr. Nov 1997;127(11):2187-93. [Medline].

31. Tang N, Luo NJ. Prevalence of parasites in kindergarten children. Int J Infect Dis. May 2005;9(3):178-9. [Medline].

32. Tinuade O, John O, Saheed O, et al. Parasitic etiology of childhood diarrhea. Indian J Pediatr. Dec 2006;73(12):1081-4. [Medline].

33. Tokmak N, Koc Z, Ulusan S, Koltas IS, Bal N. Computed tomographic findings of trichuriasis. World J Gastroenterol. Jul 14 2006;12(26):4270-2. [Medline].

34. Turner JD, Jackson JA, Faulkner H, et al. Intensity of intestinal infection with multiple worm species is related to regulatory cytokine output and immune hyporesponsiveness. J Infect Dis. Apr 15 2008;197(8):1204-12. [Medline].

35. Walden J. Parasitic diseases. Other roundworms. Trichuris, hookworm, and Strongyloides. Prim Care. Mar 1991;18(1):53-74. [Medline].

36. Wang LJ, Cao Y, Shi HN. Helminth infections and intestinal inflammation. World J Gastroenterol. Sep 7 2008;14(33):5125-32. [Medline].

37. Wani SA, Ahmad F, Zargar SA, Dar ZA, Dar PA, Tak H, et al. Soil-transmitted helminths in relation to hemoglobin status among school children of the Kashmir Valley. J Parasitol. Jun 2008;94(3):591-3. [Medline].

38. Xu LQ, Yu SH, Jiang ZX, et al. Soil-transmitted helminthiases: nationwide survey in China. Bull World Health Organ. 1995;73(4):507-13. [Medline].

Keywords

whipworm, anemia, ascaris, Nematoda, parasite, parasite infection, parasitic disease, rectal prolapse, trichuriasis, Trichuris dysentery syndrome, Trichuris trichiura, T trichiura

Contributor Information and Disclosures

Author

Robert W Tolan Jr, MD, Chief, Division of Allergy, Immunology and Infectious Diseases, The Children's Hospital at Saint Peter's University Hospital; Clinical Associate Professor of Pediatrics, Drexel University College of Medicine
Robert W Tolan Jr, MD is a member of the following medical societies: American Academy of Pediatrics, American Medical Association, American Society for Microbiology, American Society of Tropical Medicine and Hygiene, Infectious Diseases Society of America, Pediatric Infectious Diseases Society, Phi Beta Kappa, and Physicians for Social Responsibility
Disclosure: GlaxoSmithKline Honoraria Speaking and teaching; MedImmune Honoraria Consulting; MedImmune Honoraria Speaking and teaching; Merck Honoraria Speaking and teaching; Novartis Honoraria Speaking and teaching; sanofi pasteur Grant/research funds Unrestricted research grant; sanofi pasteur  Consulting; sanofi pasteur Honoraria Speaking and teaching; Tap Honoraria Speaking and teaching; Baxter Healthcare Honoraria Speaking and teaching

Coauthor(s)

Tina Slusher, MD, Assistant Professor, Department of Pediatrics, Section of Pediatric Critical Care, West Virginia University
Tina Slusher, MD is a member of the following medical societies: Society of Critical Care Medicine
Disclosure: Nothing to disclose.

Steven L Lanski, MD, Department of Pediatrics, Division of Pediatric Emergency Medicine, Assistant Professor, Emory University and Children's Healthcare of Atlanta at Egleston
Steven L Lanski, MD is a member of the following medical societies: American Academy of Pediatrics
Disclosure: Nothing to disclose.

Medical Editor

Ashir Kumar, MBBS, MD, FAAP, Professor, Department of Pediatrics and Human Development, College of Human Medicine, Michigan State University; Consulting Staff, Department of Pediatrics, EW Sparrow Hospital
Ashir Kumar, MBBS, MD, FAAP is a member of the following medical societies: American Academy of Pediatrics, American Association of Physicians of Indian Origin, American Federation for Clinical Research, American Society for Microbiology, Infectious Diseases Society of America, and Pediatric Infectious Diseases Society
Disclosure: Nothing to disclose.

Pharmacy Editor

Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine
Disclosure: Pfizer Inc Stock Investment from financial planner; Avanir Pharma Stock Investment from financial planner ; WebMD Salary and stock Employment and investment from financial planner

Managing Editor

Martin Weisse, MD, Program Director, Associate Professor, Department of Pediatrics, West Virginia University
Martin Weisse, MD is a member of the following medical societies: Ambulatory Pediatric Association, American Academy of Pediatrics, and Pediatric Infectious Diseases Society
Disclosure: Nothing to disclose.

CME Editor

Daniel Rauch, MD, FAAP, Director, Pediatric Hospitalist Program, Associate Professor, Department of Pediatrics, New York University School of Medicine
Daniel Rauch, MD, FAAP is a member of the following medical societies: Ambulatory Pediatric Association, American Academy of Pediatrics, and Society of Hospital Medicine
Disclosure: Baxter Honoraria Consulting; Pfizer Honoraria Consulting

Chief Editor

Russell W Steele, MD, Head, Division of Pediatric Infectious Diseases, Ochsner Children's Health Center; Clinical Professor, Department of Pediatrics, Tulane University School of Medicine
Russell W Steele, MD is a member of the following medical societies: American Academy of Pediatrics, American Association of Immunologists, American Pediatric Society, American Society for Microbiology, Infectious Diseases Society of America, Louisiana State Medical Society, Pediatric Infectious Diseases Society, Society for Pediatric Research, and Southern Medical Association
Disclosure: None None None

© 1994- by Medscape.
All Rights Reserved
(http://www.medscape.com/public/copyright)