Cystic Fibrosis: Etiology and Pathology (Pediatric Nursing)

00:01 Now, we'll cover cystic fibrosis.

00:04 Cystic fibrosis is a genetic disease meaning it's caused by a person's genes.

00:08 It mainly affects the lungs and the digestive systems in the body, causing breathing problems and problems digesting foods.

00:16 Cystic fibrosis affects the glands that produce mucus and sweat.

00:20 These are the lungs and the GI tract.

00:22 The mucus is going to become thick and sticky.

00:26 Lung infections can develop and lung functioning decreases over time.

00:30 And unfortunately, currently, there is no cure.

00:34 Cystic fibrosis affects at least 30,000 people in the United States.

00:38 All newborns are screened for cystic fibrosis on part of their required newborn screen.

00:44 The life expectancy of a patient with cystic fibrosis is 30 or 40 years.

00:48 Some patients live beyond this.

00:51 Cystic fibrosis ultimately results in respiratory failure.

00:56 So, every person has 2 copies of the cystic fibrosis transmembrane conductance regulator gene.

01:03 We'll refer to this as the CFTR gene.

01:07 Cystic fibrosis is an autosomal recessive disorder, so a person must inherit 2 mutated copies of the CFTR gene, 1 from each parent, to have cystic fibrosis.

01:18 This pedigree on the left, both parents are carriers.

01:22 So we can see as they have their offspring, their children will have a 25% chance of having cystic fibrosis.

01:29 This is the child on the left.

01:30 They've inherited both mutated genes.

01:33 Now, this family will have a 50% chance with each pregnancy of having a child who is a carrier for cystic fibrosis, and they'll also have a 25% chance of having a completely unaffected child.

01:44 So the child will not be a carrier and will not have cystic fibrosis.

01:49 Another situation would be if 1 parent has cystic fibrosis, so they have 2 mutated copies of the gene, and 1 parent is a carrier with 1 mutated copy.

01:58 This family's going to have a 50% percent chance of having a child with cystic fibrosis, which inherits both genes, and 50% chance that their children will be carriers.

02:10 So, mucus is a slippery substance that lubricates and protects the linings of the airways, digestive system, reproductive system, and other organs and tissues.

02:18 In patients with cystic fibrosis, the body is going to produce mucus that is abnormally thick and sticky, and this is going to lead to lots of problems around the body.

02:27 In the sinuses, this can contribute to sinusitis, which is infection and inflammation in the sinuses.

02:33 In the lungs, the patients are going to have thick, sticky mucus buildup, and this is a good place for bacterial infection.

02:40 In the skin, the sweat glands can produce salty sweat.

02:44 In the liver, the biliary duct can get blocked by mucus.

02:48 The same thing can happen in the pancreas.

02:51 In the intestines, they're going to get filled up with mucus and they cannot fully absorb nutrients.

02:57 The reproductive organs are also going to get backed up with mucus, and this can cause problems with fertility or delayed puberty.

03:04 On the top here, you'll see a normal airway in a patient without cystic fibrosis.

03:09 Their airway wall is smooth and it's going to be lined with a thin layer of mucus.

03:14 This is in contrast to a patient with cystic fibrosis.

03:17 Their airway is going to become widened and there's going to be thick, sticky mucus that's going to block their airway.

03:23 The patient may have blood in their mucus and this is a great breeding ground for bacterial infection.