Niacin deficiency: Difference between revisions

From IDWiki
(Created page with "== Background == * Deficiency in the water-soluble vitamin B3 * Also known as pellagra * Risk factors include: ** Resource-limited countries were diet is heavy in untreated corn or sorghum (India, parts of China, and Africa; in Mexico, corn is treated and pellagra is rare) ** Alcohol use disorder ** Complication of bariatric suerger ** Anorexia nervosa ** Malasorption * Can also be seen in carcinoid syndrome, prolonged use of isoniazid, and Hartnup disease...")
 
No edit summary
Line 14: Line 14:
   
 
* Classic triad of photosensitive pigmented dermatitis, diarrhea, and dementia
 
* Classic triad of photosensitive pigmented dermatitis, diarrhea, and dementia
  +
* Causes symmetric hyperpigmented rash that looks like a sunburn, on sunexposed skin ("Casal necklace")
  +
* Also: red tongue, diarrhea, vomiting, insomnia, anxiety, disorientation, delusions, dementia, and encephalopathy
   
 
== Investigations ==
 
== Investigations ==

Revision as of 12:09, 14 July 2024

Background

  • Deficiency in the water-soluble vitamin B3
  • Also known as pellagra
  • Risk factors include:
    • Resource-limited countries were diet is heavy in untreated corn or sorghum (India, parts of China, and Africa; in Mexico, corn is treated and pellagra is rare)
    • Alcohol use disorder
    • Complication of bariatric suerger
    • Anorexia nervosa
    • Malasorption
  • Can also be seen in carcinoid syndrome, prolonged use of isoniazid, and Hartnup disease

Clinical Manifestations

  • Classic triad of photosensitive pigmented dermatitis, diarrhea, and dementia
  • Causes symmetric hyperpigmented rash that looks like a sunburn, on sunexposed skin ("Casal necklace")
  • Also: red tongue, diarrhea, vomiting, insomnia, anxiety, disorientation, delusions, dementia, and encephalopathy

Investigations

  • Urinary N-methylnicotinamide or erythrocyte NAD:NADP ratio
    • Not readily available