Isoniazid exposure and pyridoxine levels in human immunodeficiency virus associated distal sensory neuropathy

Int J Tuberc Lung Dis. 2015 Nov;19(11):1312-9. doi: 10.5588/ijtld.15.0467.

Abstract

Setting: Distal sensory polyneuropathy (DSP) may manifest in human immunodeficiency virus (HIV) infected individuals before or after antiretroviral therapy (ART). DSP can also occur in response to isoniazid (INH); this can be prevented by pyridoxine supplementation. N-acetyltransferase 2 (NAT2) polymorphisms influence drug acetylation and possibly the risk for INH-associated DSP.

Objective: To investigate the relationship between previous/current TB, pyridoxine deficiency and DSP in HIV-infected individuals enrolled in a government-sponsored HIV programme.

Design: Neuropathy assessments were performed among 159 adults pre-ART and 12 and 24 weeks thereafter. DSP was defined as ⩾1 neuropathic symptom and sign. NAT2 genotypes predicted acetylation phenotype. Serum pyridoxine levels (PLP) were quantified at baseline and week 12.

Results: DSP was present in 16% of individuals pre-ART and was associated with previous/current TB (P = 0.020). Over 50% were pyridoxine deficient (PLP < 25 nmol/l), despite supplementation with vitamin B complex supplements (2-4 mg/day pyridoxine). Those with a history of TB and pre-ART DSP were more likely to be pyridoxine deficient (P = 0.029), and slow/intermediate NAT2 phenotypes impacted on their PLP levels. Incident/worsening DSP after ART developed in 21% of the participants. PLP levels remained low after ART, particularly among those with prior TB, but without an association between DSP or NAT2 phenotypes.

Conclusion: Adequate pyridoxine supplementation before ART initiation should be prioritised, particularly in those with a history of TB or current TB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antiretroviral Therapy, Highly Active
  • Arylamine N-Acetyltransferase / genetics
  • Coinfection / drug therapy
  • Female
  • HIV Infections / drug therapy
  • Humans
  • Isoniazid / adverse effects*
  • Isoniazid / therapeutic use
  • Male
  • Polyneuropathies / diagnosis*
  • Polyneuropathies / drug therapy*
  • Pyridoxine / blood*
  • Risk Factors
  • South Africa
  • Tuberculosis / drug therapy
  • Vitamin B 6 Deficiency / diagnosis*
  • Vitamin B Complex / therapeutic use*

Substances

  • Vitamin B Complex
  • Arylamine N-Acetyltransferase
  • NAT2 protein, human
  • Pyridoxine
  • Isoniazid