Cystic fibrosis

Last reviewed: 2 Sep 2022
Last updated: 02 Jun 2020

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • positive newborn screen
  • failure to pass meconium
  • failure to thrive
  • voracious appetite
  • wet-sounding cough
  • recurrent infection
  • chronic sinusitis
  • genital abnormalities in males
  • haemoptysis
More key diagnostic factors

Other diagnostic factors

  • malabsorptive stool with steatorrhoea
  • digital clubbing
  • gastro-oesophageal reflux
  • wheeze
  • increased anteroposterior (AP) diameter of the chest
  • history of pancreatitis
  • history of acute appendicitis
  • enlarged liver or spleen
Other diagnostic factors

Risk factors

  • family history of CF
  • known carrier status of both parents
  • ethnicity
More risk factors

Diagnostic investigations

1st investigations to order

  • sweat test
  • immunoreactive trypsinogen (IRT) test (newborn screening)
  • genetic testing
More 1st investigations to order

Investigations to consider

  • sinus x-ray
  • deep throat swab
More investigations to consider

Treatment algorithm

ACUTE

neonates with meconium ileus/partial distal intestinal obstruction

complete intestinal obstruction or peritonitis

acute respiratory infection

asthma exacerbation without infection

ONGOING

respiratory disease

gastrointestinal disease

Contributors

Authors

Samuel B. Goldfarb, MD

Professor of Clinical Pediatrics

The Children's Hospital of Philadelphia

Perelman School of Medicine at the University of Pennsylvania

Philadelphia

PA

Disclosures

SBG declares that he has no competing interests.

Maureen Banfe Josephson, DO

Assistant Professor of Pediatrics

The Children's Hospital of Philadelphia

Perelman School of Medicine at the University of Pennsylvania

Philadelphia

PA

Disclosures

MBJ declares that she has no competing interests.

Acknowledgements

Dr Samuel B. Goldfarb and Dr Maureen Banfe Josephson would like to gratefully acknowledge Dr James L. Kreindler, a previous contributor to this topic.

Disclosures

JLK declares that he has no competing interests.

Peer reviewers

Sangeeta M. Bhorade, MD

Associate Professor of Medicine

Medical Director

Lung Transplant Program

University of Chicago Hospitals

Chicago

IL

Disclosures

SMB declares that she has no competing interests.

Alan Smyth, MA, MBBS, MRCP, MD, FRCPCH

Associate Professor & Reader in Child Health

Division of Child Health

University of Nottingham

Queens Medical Centre

Nottingham

UK

Disclosures

AS declares that he has no competing interests.

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  • Patient leaflets

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