Sweat test in patients with glucose-6-phosphate-1-dehydrogenase deficiency

Arch Dis Child. 2008 Oct;93(10):878-9. doi: 10.1136/adc.2007.132688. Epub 2008 May 2.

Abstract

Background: A false-positive sweat test in patients with deficiency of glucose-6-phosphate-1-dehydrogenase (EC 1.1.1.49; G6PD) is repeatedly reported.

Methods: Sweat chloride or conductivity was measured in 11 patients with G6PD deficiency.

Results: Mean (SD) chloride level (n = 8, median age 9.2 years, range 1.9-48.5) was 18.8 (9.6 mmol/l) and, mean (SD) sodium level was 26.0 (10.0 mmol/l), respectively, and mean (SD) conductivity (n = 3, median age 6.6 years, range 1.9-40.5) was 34.3 (6.5 mmol/l).

Conclusion: In sweat of 11 patients with G6PD deficiency we did not find any abnormality. The reason for alleged false-positive sweat test in patients with G6PD deficiency is not known and we were unable to identify any original reference. It appears that tables of putative false-positive sweat tests in several disease states have been directly "copied and pasted" from one paper or textbook to another without verifying the original literature, a phenomenon one can call "chain citation".

MeSH terms

  • Adult
  • Child
  • Child, Preschool
  • Chlorides / analysis
  • Cystic Fibrosis / diagnosis
  • Diagnosis, Differential
  • Electric Conductivity
  • False Positive Reactions
  • Female
  • Glucosephosphate Dehydrogenase Deficiency / diagnosis*
  • Glucosephosphate Dehydrogenase Deficiency / metabolism
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Sodium / analysis
  • Sweat / chemistry*

Substances

  • Chlorides
  • Sodium