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Pellagra neuropathy — Clinical Guidelines

Overview

Pellagra is a clinical syndrome resulting from severe niacin (vitamin B3) deficiency, characterized by the classic "4Ds": dermatitis, diarrhea, dementia, and, if untreated, death. It often occurs in contexts of malnutrition, alcoholism, and certain gastrointestinal disorders 1 3 6.

Diagnosis

Clinical Presentation: Dermatitis (commonly photosensitive), diarrhea, cognitive impairment, and malnutrition 1 3 4.

Laboratory Tests: Elevated levels of urinary N-methylnicotinamide (a marker of niacin deficiency) can be useful, though not universally available 6.

Biochemical Markers: Low plasma tryptophan levels may indicate niacin deficiency 6.

Differential Diagnosis: High index of suspicion required due to varied presentations, especially in chronic alcoholism 1 11.

Management

First-Line Treatment: Oral niacinamide or nicotinic acid supplementation; typical initial dose is 100-300 mg daily, adjusted based on response 3 14.

Adjunctive Measures: Correction of underlying nutritional deficiencies, including other B vitamins; dietary modification to include niacin-rich foods 3 15.

Supportive Care: Management of symptoms such as electrolyte imbalances and gastrointestinal issues 1 14.

Special Populations

Alcoholism: Common in alcoholics; treatment must address both niacin deficiency and alcohol use disorder 1 11.

Pediatrics: Rare but can occur in malnourished children; prompt diagnosis and supplementation are crucial 3.

Elderly: Increased risk due to malabsorption and polypharmacy; careful monitoring of vitamin intake and absorption 15.

Key Recommendations

High Index of Suspicion for Diagnosis: Maintain vigilance for pellagra in patients with chronic alcoholism, malnutrition, and unexplained neurological symptoms (Evidence: Moderate) 1 11.

Initiate Niacin Supplementation: Start with oral niacinamide or nicotinic acid at doses of 100-300 mg daily for treatment (Evidence: Expert opinion) 3 14.

Address Underlying Causes: Correct nutritional deficiencies and manage contributing factors like alcoholism and gastrointestinal disorders (Evidence: Moderate) 1 15.

Monitor Response to Treatment: Regular follow-up to assess clinical improvement and adjust supplementation as needed (Evidence: Expert opinion) 14.

References

1 Chen X, Yang C, Du C, Jiang G. Clinical analysis of alcoholic pellagra: A single-center retrospective study. Journal of cosmetic dermatology 2022. link 2 Nashawaty M, Mahmoud A, Hassan S, Mohammed TO, Hoenig LJ. Nutrition and art: 19th century images of scurvy, chlorosis, and pellagra. Clinics in dermatology 2021. link 3 Cao S, Wang X, Cestodio K. Pellagra, an Almost-Forgotten Differential Diagnosis of Chronic Diarrhea: More Prevalent Than We Think. Nutrition in clinical practice : official publication of the American Society for Parenteral and Enteral Nutrition 2020. link 4 Rivadeneira A, Moyer P, Salciccioli JD. Pellagra in the USA: unusual manifestations of a rare entity. BMJ case reports 2019. link 5 Akakpo AS, Saka B, Teclessou JN, Mouhari-Toure A, Moise Elegbede Y, Kombate K et al.. Pellagra and pellagra-like erythema in a hospital setting in Lomé, Togo : retrospective study from 1997 to 2017. Medecine et sante tropicales 2019. link 6 Badawy AA. Pellagra and alcoholism: a biochemical perspective. Alcohol and alcoholism (Oxford, Oxfordshire) 2014. link 7 Steffen C. Pellagra. Skinmed 2012. link 8 Lanska DJ. The discovery of niacin, biotin, and pantothenic acid. Annals of nutrition & metabolism 2012. link 9 Bilgili SG, Karadag AS, Calka O, Altun F. Isoniazid-induced pellagra. Cutaneous and ocular toxicology 2011. link 10 Piro A, Tagarelli G, Lagonia P, Tagarelli A, Quattrone A. Casimir Funk: his discovery of the vitamins and their deficiency disorders. Annals of nutrition & metabolism 2010. link 11 Pipili C, Cholongitas E, Ioannidou D. The diagnostic importance of photosensitivity dermatoses in chronic alcoholism: report of two cases. Dermatology online journal 2008. link 12 Delgado-Sanchez L, Godkar D, Niranjan S. Pellagra: rekindling of an old flame. American journal of therapeutics 2008. link 13 Prakash R, Gandotra S, Singh LK, Das B, Lakra A. Rapid resolution of delusional parasitosis in pellagra with niacin augmentation therapy. General hospital psychiatry 2008. link 14 Varella Morandi Junqueira-Franco M, Ernesto Troncon L, Garcia Chiarello P, do Rosário Del Lama Unamuno M, Afonso Jordao A, Vannucchi H. Intestinal permeability and oxidative stress in patients with alcoholic pellagra. Clinical nutrition (Edinburgh, Scotland) 2006. link 15 Pitsavas S, Andreou C, Bascialla F, Bozikas VP, Karavatos A. Pellagra encephalopathy following B-complex vitamin treatment without niacin. International journal of psychiatry in medicine 2004. link 16 Segal I, Hale M, Demetriou A, Mohamed AE. Pathological effects of pellagra on the esophagus. Nutrition and cancer 1990. link 17 Grande Covian F. Vitamin deficiencies during the Spanish Civil War in Madrid: a reminiscence. Acta vitaminologica et enzymologica 1982. link

Pellagra neuropathy