Summary
Definition
History and exam
Key diagnostic factors
- diarrhea
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
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
Diagnostic investigations
1st investigations to order
- stool microscopy
- Cryptosporidium antigen detection
Investigations to consider
- ultrasound scan of the biliary tract
- CT scan of the biliary tract
- endoscopic retrograde cholangiopancreatography (ERCP)
- polymerase chain reaction for Cryptosporidium DNA
- polymerase chain reaction for Cryptosporidium species identification
Treatment algorithm
immunocompetent
immunocompromised
Contributors
Authors
Rachel M. Chalmers, BSc, PhD
Consultant Clinical Scientist/Honorary Professor
Director of UK Cryptosporidium Reference Unit
Public Health Wales Microbiology
Singleton Hospital
Swansea
UK
Disclosures
RMC is a member of the following boards: WHO Water Quality and Health Technical Advisory Group; the UK Standards for Microbiology Investigations Bacteriology Working Group; Public Health England Water Advisory Group and Gastro-Intestinal Leads Group; Wales Microbiology Standing Specialist Advisory Group. RMC has received grant funding from EU FP7 project "Aquavalens" and EFSA partnering grant project IMPACT and has undertaken contract research from UK Water Industry Research. RMC has received payments for lectures and reimbursement for conference travel and subsistence. 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 an author of a number of references cited in this topic.
Peer reviewers
Beth Kirkpatrick, MD
Assistant Professor
Infectious Diseases
University of Vermont College of Medicine
Burlington
VT
Disclosures
BK declares that she has no competing interests.
Yann Meunier, MD
Director
Stanford Health Promotion Network
Stanford School of Medicine
Palo Alto
CA
Disclosures
YM declares that he has no competing interests.
Differentials
- Acute diarrhea
- Chronic diarrhea
- Crohn disease
More DifferentialsGuidelines
- Guidelines for the prevention and treatment of opportunistic infections in HIV-infected adults and adolescents
- Guidelines for the prevention and treatment of opportunistic infections in HIV-exposed and HIV-infected children
More GuidelinesPatient leaflets
Diarrhea in adults
Diarrhea in children
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