Inability to secrete thick pancreatic secretions leads to pancreatic autodigestion and progressive damage. Chronic sinus infections are common in patients and can lead to the development of nasal polyps in childhood (a finding usually only seen in adults). Neutrophils are recruited to the site of bacterial colonization and release elastase which can lead to lung tissue destruction and development of bronchiectasis. Infections with Burkholderia cepacia can be a poor prognostic sign. Thick mucous accumulation in the lungs leads to bacterial colonization with organisms such as Staphylococcus aureus and Pseudomonas aeruginosa. Aberrant chloride transport across this channel leads to viscous secretions in the respiratory tract, pancreas, liver, intestine, and the reproductive tract. To date, more than 1300 mutations have been described. Liver cirrhosis and male infertility are other findings.ĬF is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR). Non-infectious complications include pancreatic insufficiency and fat malabsorption leading to growth failure. Given the high frequency of CF, it is critical to keep this diagnosis in mind when evaluating patients for suspected immune deficiency. Patients suffer from chronic sinopulmonary infections similar to patients with antibody deficiency syndromes. This disease is characterized by progressive lung disease which eventually leads to respiratory failure. However, the frequency in Hispanics (1 in 9000) and African Americans (1 in 15000) is not insignificant. Confirmatory DNA testing can be performed on patients with intermediate or positive sweat chloride test results.Ĭystic Fibrosis (CF) is an autosomal recessive disease which occurs with high frequency (1 in 3000 live births) among Caucasians.

This should be performed for patients with suggestive clinical history, patients with a family history of CF, or patients with positive CF newborn screen results.Ħ. The primary test for diagnosing CF is the sweat chloride test. Meconium ileus, rectal prolapse, steatorrhea, nasal polyps, and digital clubbing are clinical clues that warrant investigation for CF.ĥ. Neutrophils recruited to the lungs release proteases that lead to tissue destruction and progressive respiratory failure.Ĥ.

Accumulation of thick mucous in the lungs leads to colonization with bacteria including Pseudomonas aeruginosa and Burkholderia cepacia. This disease is caused by mutations in the CFTR protein which leads to aberrant chloride transport and generation of viscous mucous secretions in the lung, pancreas, liver, intestine, and reproductive tract.ģ. The clinical features of recurrent sinopulmonary infections can mimic the phenotype of antibody deficiency syndromes.Ģ.

Patients classically develop persistent sinus and lung infections, pancreatic insufficiency, and elevated sweat chloride levels. Cystic Fibrosis is one of the most common (1 in 3000) autosomal recessive disease among Caucasians.

What is Cystic Fibrosis What is SCID