Last reviewed: November 2017
Last updated: October  2017

Summary

Definition

History and exam

Key diagnostic factors

  • dermatitis
  • insomnia, depression, or memory loss
  • intermittent stupor
  • hallucinations or delirium
  • weakness
  • peripheral neuropathy
  • oppositional hypertonus or myoclonus
  • cogwheel rigidity
  • primitive reflexes
  • ataxia
  • nausea, vomiting, or diarrhea
  • glossitis, cheilitis, or stomatitis

Other diagnostic factors

  • fatigue
  • anxiety or paranoia
  • anorexia, weight loss, or cachexia
  • headache
  • vertigo
  • incontinence
  • constipation
  • heartburn
  • angular palpebritis

Risk factors

  • malnutrition
  • chronic alcohol abuse
  • vitamin B2 (riboflavin) deficiency
  • vitamin B6 (pyridoxine) deficiency
  • malabsorption
  • eating disorders
  • Hartnup disease
  • carcinoid syndrome
  • antituberculous drugs
  • Crohn disease
  • HIV infection
  • copper excess or deficiency
  • certain drugs
  • pregnancy and lactation
  • age >65 years
  • Alzheimer dementia
  • Parkinson disease

Diagnostic investigations

1st investigations to order

  • serum tryptophan
  • urinary N-methylnicotinamide
  • urinary N-methyl-2-pyridone-5-carboxamide
  • urinary 2-pyridone/N-methylnicotinamide ratio
  • skin biopsy
  • photosensitivity testing
  • CBC
  • serum albumin
  • serum protein
  • LFTs
  • gamma-GT
Full details

Investigations to consider

  • serum total iron
  • iron-binding capacity
  • ferritin
  • transketolase activity
  • thiamine pyrophosphate (TPP)
  • riboflavin coefficient
  • serum pyridoxal-5-phosphate
  • serum cyanocobalamin
  • serum folic acid
  • red cell folic acid
  • stool exam
  • neutral aminoaciduria
  • serum serotonin
  • platelet serotonin
  • urinary 5-hydroxyindoleacetic acid
  • HIV antibodies
  • mental state exam
  • ECG
Full details

Treatment algorithm

Contributors

Authors VIEW ALL

Senior Research Specialist

Centre for the Study of the Social and Environmental Determinants of Nutrition

Population Health, Health Systems and Innovation

HSRC

Cape Town

South Africa

Disclosures

WP declares that she has no competing interests.

Senior Research Specialist

Centre for the Study of the Social and Environmental Determinants of Nutrition

Population Health, Health Systems and Innovation

HSRC

Cape Town

South Africa

Disclosures

ZJM declares that she has no competing interests.

Professor Emeritus

Stellenbosch University

Professor Extraordinaire

University of Limpopo

South Africa

Disclosures

DL declares that he has no competing interests.

Dr Whadi-ah Parker, Dr Zandile June-Rose Mchiza, and Dr Demetre Labadarios would like to gratefully acknowledge Dr Nelia Patricia Steyn, a previous contributor, as well as Miss Nophiwe Job, Ms Nwabisa Tshefu, and Mr Machoene Derrick Sekgala for their contributions to this monograph. NPS, NJ, NT, and MDS declare that they have no competing interests.

Peer reviewers VIEW ALL

Emeritus Professor of Clinical Chemistry

University of Liverpool

UK

Disclosures

AS declares that he has no competing interests.

CBNS

Queens College

City University of New York

NY

Disclosures

AM declares that he has no competing interests.

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