Cystic Fibrosis Dr Pratima Ghimire June 2009 Cystic

Cystic Fibrosis Dr. Pratima Ghimire June, 2009

Cystic Fibrosis • Genetic disorder • Autosomal recessive • Inherited disease of secretory glands (which make mucous and sweat)

Cystic Fibrosis • Cause – Mutation in CFTR (cystic fibrosis transmembrane conductance regulator) gene – Product of this gene makes chloride ion channel

Cystic Fibrosis • Pathophysiology – Mutation in the CFTR gene – The protein created by this gene is anchored to the outer membrane of cells in the sweat glands, lungs, pancreas, and other affected organs – The protein spans this membrane and acts as a channel connecting the inner part of the cell (cytoplasm) to the surrounding fluid

Cystic Fibrosis • Pathophysiology – This channel is primarily responsible for controlling the movement of chloride from inside to outside of the cell; however, in the sweat ducts it facilitates the movement of chloride from the sweat into the cytoplasm – When the CFTR protein does not work, chloride is trapped inside the cells in the airway and outside in the skin

Cystic Fibrosis • Mucus becomes thick and sticky • Mucus builds up in lungs and blocks airways • Buildup of mucus makes it easy for bacteria to grow • This leads to repeated, serious lung infections. Over time, these infections can severely damage lungs

Cystic Fibrosis • The thick, sticky mucus also can block tubes, or ducts in pancreas • As a result, the digestive enzymes that pancreas makes can't reach small intestine • Intestines can't fully absorb fats and proteins • This can cause vitamin deficiency and malnutrition • It also can cause bulky stools, intestinal gas, a swollen belly from severe constipation, and pain or discomfort

Cystic Fibrosis • Also causes sweat to become very salty • As a result body loses large amounts of salt during sweating • This can upset the balance of minerals in blood

Cystic Fibrosis • CF causes increased risk for diabetes or osteoporosis • Also causes infertility in men, and it can make it harder for women to get pregnant

Cystic Fibrosis • Hallmarks – Salty tasting skin – Normal appetite but poor growth – Poor weight gain – Excessive mucus production – Coughing – SOB

Cystic Fibrosis • Males– infertile due to congenital B/L absence of vas deferens • Meconium ileus – typical finding in NB babies with cystic fibrosis • More common in western world

Cystic Fibrosis • Diagnosis – Sweat testing – Genetic testing • Chorionic villous sampling • amniocentesis

Cystic Fibrosis • Cure – Gene therapy at early age – to replace the defective gene – Give active form of protein product that is deficient – Lung transplantation in severe lung disease – Pancreatic enzyme supplementation in severe pancreatic deficiency