eMedicine Specialties > Infectious Diseases > Parasitic Infections

Cryptosporidiosis: Differential Diagnoses & Workup

Author: A Clinton White Jr, MD, The Paul R Stalnaker, MD, Distinguished Professor of Internal Medicine, Director, Infectious Disease Division, Department of Internal Medicine, University of Texas Medical Branch
Contributor Information and Disclosures

Updated: Jun 23, 2008

Differential Diagnoses

Amebiasis
Giardiasis
Campylobacter Infections
Isosporiasis
Cyclospora
Salmonellosis
Cytomegalovirus Colitis
Shigellosis
Escherichia Coli Infections
Gastroenteritis, Viral

Other Problems to Be Considered

Cyclospora cayetanensis infection

Workup

Laboratory Studies

  • Stool microscopy: Modified acid-fast staining of stool shows red-stained round oocysts against a blue-green background (see Image 1). White and red blood cells should not be seen in the stool. Antigen-detection assays are more sensitive and include immunofluorescent assays, enzyme-linked immunosorbent assay (ELISA), and immunochromatographic tests. Polymerase chain reaction (PCR) assays, when available, are more sensitive than other tests.
  • Stool culture: Perform a stool culture to rule out the presence of other bacterial pathogens.
  • Urea and electrolytes: These tests are used to assess electrolyte replacement requirements and the presence of prerenal uremia.
  • Liver function tests: Elevated alkaline phosphatase and glutamyl transpeptidase without hyperbilirubinemia are typical signs of biliary infection.
  • Lymphocyte subset analysis: CD4+ lymphocyte counts predict the duration of disease in patients infected with HIV. When the counts are greater than 150 cells/μL, the diarrhea is likely to resolve spontaneously, but diarrhea may be chronic with lower counts. Counts are typically less than 50 cells/μL in patients with either biliary involvement or choleralike syndromes.

Imaging Studies

  • Abdominal ultrasonography: Dilated or irregular intrahepatic and extrahepatic bile ducts, along with a thickened gallbladder, indicate biliary involvement.
  • Endoscopic retrograde cholangiopancreatography (ERCP): ERCP is often needed to diagnose sclerosing cholangitis or papillary stenosis.

Procedures

  • ERCP: Identification of Cryptosporidium oocysts in bile or intracellular forms on biopsy confirms the diagnosis of biliary cryptosporidiosis. Papillary stenosis may be present and responds symptomatically to endoscopic sphincterotomy, often with stent placement.

Histologic Findings

Histological examination of the small intestine is not required to confirm the diagnosis of cryptosporidiosis. The small intestine shows the parasite projecting from the brush border of the mucosal surface. Parasites may also be identified in bile or biliary tract biopsies.

More on Cryptosporidiosis

Overview: Cryptosporidiosis
Differential Diagnoses & Workup: Cryptosporidiosis
Treatment & Medication: Cryptosporidiosis
Follow-up: Cryptosporidiosis
Multimedia: Cryptosporidiosis
References
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References

  1. White AC Jr. Cryptosporidiosis (Cryptosporidium hominis, Cryptosporidium parvum, other species). In: Mandell GL, Bennett JE, Dolin R, ed. Principles and Practice of Infectious Diseases. 6th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2005:3215-3228.

  2. Bushen OY, Lima AA, Guerrant RL. Cryptosporidiosis. In: Guerrant RL, Walker DH, Weller PF, eds. Tropical Infectious Diseases. Philadelphia, PA: Elsevier-Churchill Livingstone Principle, Pathogens, and Practice.; 2006:1003-1014.

  3. Kosek M, Alcantara C, Lima AA, Guerrant RL. Cryptosporidiosis: an update. Lancet Infect Dis. Nov 2001;1(4):262-9. [Medline].

  4. Ramirez NE, Ward LA, Sreevatsan S. A review of the biology and epidemiology of cryptosporidiosis in humans and animals. Microbes Infect. Jul 2004;6(8):773-85. [Medline].

  5. Thompson RC, Olson ME, Zhu G, Enomoto S, Abrahamsen MS, Hijjawi NS. Cryptosporidium and cryptosporidiosis. Adv Parasitol. 2005;59:77-158. [Medline].

  6. Amin OM. Seasonal prevalence of intestinal parasites in the United States during 2000. Am J Trop Med Hyg. Jun 2002;66(6):799-803. [Medline].

  7. Amadi B, Mwiya M, Musuku J, Watuka A, Sianongo S, Ayoub A, et al. Effect of nitazoxanide on morbidity and mortality in Zambian children with cryptosporidiosis: a randomised controlled trial. Lancet. Nov 2 2002;360(9343):1375-80. [Medline].

  8. Rossignol JF, Kabil SM, el-Gohary Y, Younis AM. Effect of nitazoxanide in diarrhea and enteritis caused by Cryptosporidium species. Clin Gastroenterol Hepatol. Mar 2006;4(3):320-4. [Medline].

  9. Rossignol JF, Ayoub A, Ayers MS. Treatment of diarrhea caused by Cryptosporidium parvum: a prospective randomized, double-blind, placebo-controlled study of Nitazoxanide. J Infect Dis. Jul 1 2001;184(1):103-6. [Medline].

  10. Kotler DP, Fogleman L, Tierney AR. Comparison of total parenteral nutrition and an oral, semielemental diet on body composition, physical function, and nutrition-related costs in patients with malabsorption due to acquired immunodeficiency syndrome. JPEN J Parenter Enteral Nutr. May-Jun 1998;22(3):120-6. [Medline].

  11. Smith HV, Corcoran GD. New drugs and treatment for cryptosporidiosis. Curr Opin Infect Dis. Dec 2004;17(6):557-64. [Medline].

  12. Blackburn BG, Mazurek JM, Hlavsa M, Park J, Tillapaw M, Parrish M. Cryptosporidiosis associated with ozonated apple cider. Emerg Infect Dis. Apr 2006;12(4):684-6. [Medline].

  13. Buch K, Nguyen S, Divino CM, Weber K, Morotti RA. Cryptosporidiosis presenting as acute appendicitis: a case report. Am Surg. Jun 2005;71(6):537-8. [Medline].

  14. Cunha BA. Antibiotic Essentials. 5th ed. Royal Oak, Mich: Physicians Press; 2006.

  15. Insulander M, Lebbad M, Stenström TA, Svenungsson B. An outbreak of cryptosporidiosis associated with exposure to swimming pool water. Scand J Infect Dis. 2005;37(5):354-60. [Medline].

  16. Mac Kenzie WR, Hoxie NJ, Proctor ME, Gradus MS, Blair KA, Peterson DE, et al. A massive outbreak in Milwaukee of cryptosporidium infection transmitted through the public water supply. N Engl J Med. Jul 21 1994;331(3):161-7. [Medline].

  17. Mahdi NK, Ali NH. Cryptosporidiosis and other intestinal parasitic infections in patients with chronic diarrhea. Saudi Med J. Sep 2004;25(9):1204-7. [Medline].

  18. Roy SL, DeLong SM, Stenzel SA, Shiferaw B, Roberts JM, Khalakdina A. Risk factors for sporadic cryptosporidiosis among immunocompetent persons in the United States from 1999 to 2001. J Clin Microbiol. Jul 2004;42(7):2944-51. [Medline].

  19. Yoder JS, Beach MJ. Cryptosporidiosis surveillance--United States, 2003-2005. MMWR Surveill Summ. Sep 7 2007;56(7):1-10. [Medline].

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Further Reading

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Keywords

cryptosporidiosis, biliary cryptosporidiosis, calf scours, slim disease, Cryptosporidium parvum, C parvum, Cryptosporidium hominis, C hominis, cryptosporidia, Apicomplexa protozoan, diarrhea, abdominal cramps, low-grade fever, acalculous cholecystitis, sclerosing cholangitis, papillary stenosis, pancreatitis

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Contributor Information and Disclosures

Author

A Clinton White Jr, MD, The Paul R Stalnaker, MD, Distinguished Professor of Internal Medicine, Director, Infectious Disease Division, Department of Internal Medicine, University of Texas Medical Branch
A Clinton White Jr, MD is a member of the following medical societies: American Association for the Advancement of Science, American College of Physicians, American Federation for Medical Research, American Society of Tropical Medicine and Hygiene, Christian Medical & Dental Society, and Infectious Diseases Society of America
Disclosure: Nothing to disclose.

Medical Editor

Jeffrey D Band, MD, Clinical Professor of Medicine, Wayne State University School of Medicine; Director, Division of Infectious Diseases and International Medicine, William Beaumont Hospital Corporation
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

Managing Editor

Joseph F John Jr, MD, FACP, FIDSA, FSHEA, Clinical Professor of Medicine, Molecular Genetics and Microbiology, Medical University of South Carolina; Associate Chief of Staff for Education, Ralph H Johnson Veterans Affairs Medical Center
Disclosure: BioMerieux Honoraria Review panel membership; Cubist Honoraria Review panel membership; Pfizer Honoraria Speaking and teaching; Merck Stock dividends stock holdings

CME Editor

Eleftherios Mylonakis, MD, Clinical and Research Fellow, Department of Internal Medicine, Division of Infectious Diseases, Massachusetts General Hospital
Eleftherios Mylonakis, MD is a member of the following medical societies: American Association for the Advancement of Science, American College of Physicians, American Society for Microbiology, and Infectious Diseases Society of America
Disclosure: Nothing to disclose.

Chief Editor

Burke A Cunha, MD, Professor of Medicine, State University of New York School of Medicine at Stony Brook; Chief, Infectious Disease Division, Winthrop-University Hospital
Burke A Cunha, MD is a member of the following medical societies: American College of Chest Physicians, American College of Physicians, and Infectious Diseases Society of America
Disclosure: Nothing to disclose.

 
 
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