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Alcohol-induced liver disease
Alpha 1-antitrypsin deficiency
Benign liver tumors
Cholestatic liver disease
Non-alcoholic fatty liver disease
Primary biliary cirrhosis
Primary sclerosing cholangitis
Pancreatic neuroendocrine neoplasms
Familial adenomatous polyposis
Juvenile polyposis syndrome
Small bowel ischemia and infarction
Protein losing enteropathy
Short bowel syndrome (NORD)
Small bowel bacterial overgrowth syndrome
Diverticulosis and diverticulitis
Irritable bowel syndrome
Cleft lip and palate
Congenital diaphragmatic hernia
Diffuse esophageal spasm
Eosinophilic esophagitis (NORD)
Gastroesophageal reflux disease (GERD)
Cyclic vomiting syndrome
Gastric dumping syndrome
Dental caries disease
Gingivitis and periodontitis
Temporomandibular joint dysfunction
Appendicitis: Pathology review
Cirrhosis: Pathology review
Colorectal polyps and cancer: Pathology review
Congenital gastrointestinal disorders: Pathology review
Diverticular disease: Pathology review
Esophageal disorders: Pathology review
Gallbladder disorders: Pathology review
Gastrointestinal bleeding: Pathology review
GERD, peptic ulcers, gastritis, and stomach cancer: Pathology review
Inflammatory bowel disease: Pathology review
Jaundice: Pathology review
Malabsorption syndromes: Pathology review
Neuroendocrine tumors of the gastrointestinal system: Pathology review
Pancreatitis: Pathology review
Viral hepatitis: Pathology review
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Alpha-1 Antitrypsin Deficiency - Sharing your story
Alpha-1 antitrypsin deficiency is a genetic disorder in which a protein called alpha-1 antitrypsin is defective or absent, and it causes lung and liver disease.
Trypsins are a type of protease, which is an enzyme that can break down other proteins.
So this antitrypsin protein is a protease inhibitor, and inactivates trypsins, thereby preventing protein breakdown.
The “alpha-1” is just a holdover from when the protein was discovered – a letter and number combination given before its role was known.
Now, in the lungs, if we zoom in on a tiny alveolus—where gas exchange happens—if there’s some sort of infection or other cause of inflammation, immune cells like neutrophils arrive on the scene.
Neutrophils make an enzyme called neutrophil elastase, a protease capable of breaking down elastin, which is an extracellular matrix protein that gives elasticity and strength to lung tissues.
So while these little guys can help fight off infection by breaking down proteins of the bacteria, it can also go on to break down that precious elastin.
Fortunately, the liver makes alpha-1 antitrypsin which gets released into the blood and sent to the lungs, where it inhibits neutrophil elastase just like it inhibits trypsin, inactivating it before it can break down the protein elastin.
Without alpha-1 antitrypsin, the opposite happens - neutrophil elastase goes unchecked, and it damages the walls of the alveoli, and without that elastin, the alveoli loses its elasticity and structural integrity.
Zooming out a bit and looking at the acinus, which is a bunch of alveoli, it just turns into one big cavity. This destruction and enlargement of the air spaces is called emphysema.
It turns out that emphysema can develop in a couple different ways, and alpha-1 antitrypsin deficiency causes pan-acinar emphysema, meaning the whole acinus is affected, and it also tends to affect the lungs’ lower lobes the most.
Another effect of unchecked inflammation in alpha-1 antitrypsin deficiency is chronic bronchitis, resulting from increased mucus production and narrowing of the airways.
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