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Cryptosporidiosis

Last reviewed: 9 Nov 2024
Last updated: 12 Dec 2023

Summary

Definition

History and exam

Key diagnostic factors

  • diarrhea
Full details

Other diagnostic factors

  • abdominal pain
  • vomiting
  • loss of appetite
  • low-grade fever
  • loss of weight
  • right upper quadrant abdominal pain
  • jaundice
  • nasal discharge and facial pain
  • cough and dyspnea
Full details

Risk factors

  • contact with farm animals, especially calves and lambs
  • international travel
  • age: 3 years or younger
  • immune deficiency: T-cell-mediated
  • swimming and recreational water sports
  • drinking unfiltered water
  • toileting or changing diapers of young children
  • Malnutrition
Full details

Diagnostic tests

1st tests to order

  • polymerase chain reaction (PCR) for Cryptosporidium species identification
  • stained stool microscopy
  • Cryptosporidium antigen detection
Full details

Tests to consider

  • ultrasound scan of the biliary tract
  • CT scan of the biliary tract
  • endoscopic retrograde cholangiopancreatography (ERCP)
Full details

Treatment algorithm

ACUTE

immunocompetent

immunocompromised

Contributors

Authors

Rachel M. Chalmers, BSc, PhD

Consultant Clinical Scientist/Honorary Professor

Director of the Cryptosporidium Reference Unit (England and Wales)

Public Health Wales Microbiology

Singleton Hospital

Swansea

UK

Disclosures

RMC is an author of a number of references cited in this topic.

Angharad P. Davies, MA, MBBCh, MRCP, FRCPath, PhD

Clinical Associate Professor

College of Medicine

Swansea University

Swansea

UK

Disclosures

APD is a Trustee Board Member for the Royal College of Pathologists and is an author of a number of references cited in this topic.

Peer reviewers

Shauna Gunaratne, MD, MPH, DTM&H, CTropMed

Assistant Professor of Clinical Medicine

Department of Medicine

Division of Infectious Diseases

Columbia University Irving Medical Center

New York

NY

Disclosures

SG declares that she has no competing interests.

Judy Streit, MD

Clinical Professor

University of Iowa Hospitals and Clinics

Iowa City

IA

Disclosures

JS declares that she has no competing interests.

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