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


CONCLUSIONS
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".
Casaulta
C
C
Department of Paediatrics, University of Berne, Switzerland.
Stirnimann
A
A
Schoeni
M H
MH
Barben
J
J
D000328:Adult; D002648:Child; D002675:Child, Preschool; D002712:Chlorides / Q000032:analysis; D003550:Cystic Fibrosis / Q000175:diagnosis; D003937:Diagnosis, Differential; D004553:Electric Conductivity; D005189:False Positive Reactions; D005260:Female; D005955:Glucosephosphate Dehydrogenase Deficiency / Q000175:diagnosis* / Q000378:metabolism; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012964:Sodium / Q000032:analysis; D013542:Sweat / Q000737:chemistry*
D002712:Chlorides; D012964:Sodium