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Haemochromatosis

Also known as: Hemochromatosis, Iron overload

Haemochromatosis

Disorder of iron overload, most commonly hereditary (autosomal recessive, predominantly caused by HFE gene mutations, particularly C282Y homozygosity, most prevalent in populations of Northern European descent), causing inappropriately increased intestinal iron absorption and progressive deposition in the liver, heart, pancreas, joints, skin, and pituitary gland.

Secondary iron overload occurs from repeated blood transfusion (see Sickle Cell Disease and Leukemia entries) or, less commonly, from excessive iron intake or ineffective erythropoiesis in conditions such as thalassemia.

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Continue reading · Emergency, Internal medicine

Ulcerative Colitis

Also known as: UC

Ulcerative Colitis

Chronic relapsing-remitting inflammatory bowel disease characterized by continuous mucosal inflammation limited to the colon, always involving the rectum and extending proximally in a continuous (non-skip) pattern: distinguishes from Crohn's disease (transmural, skip lesions, can affect any part of GI tract).

Etiology multifactorial: genetic susceptibility, dysregulated mucosal immune response to gut microbiota, environmental triggers.

Classified by extent (Montreal classification):

  • Proctitis: limited to rectum

  • Left-sided colitis: extends to splenic flexure

  • Extensive colitis (pancolitis): extends beyond splenic flexure, may involve entire colon

Classified by severity (Truelove and Witts criteria commonly used): mild, moderate, severe: based on stool frequency, blood, systemic symptoms, inflammatory markers.