Frequency of glutamic acid decarboxylase autoantibodies in Mexican diabetic children.
OBJECTIVE
Use radio binding assay (RBA) to quantify the frequency of autoantibodies to glutamic acid decarboxylase in Mexican children with type 1 diabetes mellitus (DM 1).


METHODS
GAD antibodies were measured in 140 mestizo children with DM 1, 66 female (47.14%) and 74 male (52.8%); age 11.7 +/- 3.55 years, and range 1.10 to 18.5 years. Most patients were treated with intermediate acting insulin, and some with the former combined with regular insulin. Mean disease duration was 3.11 +/- 2.94 years, and range 1 month to 14.5 years. Once the signed written consent was obtained, a 5.0-mL blood sample was drawn, immediately centrifuged, and the serum was kept frozen to -20 degrees C until RBA evaluation was performed with a commercial kit.


RESULTS
The anti-GAD was positive in 76 DM 1 patients (54.28%) with values from 1.11 to 156.73 U/mL, and negative in 64 (45.71%). In 19 positive anti-GAD patients, the test was repeated and levels were found between 1.38 and 156.62 U/mL. An initial control group consisting of 25 healthy non-related volunteers matched by sex and age, showed negative anti-GAD for all.


CONCLUSIONS
The frequency of anti-GAD in these patients was lower than that of the DM 1 European patients, but similar to that of Asians. This supports the heterogeneity of the etiopathogenic factors of DM 1 in different ethnic groups.
Mendoza-Morfín
F
F
Department of Pediatric Endocrinology, National Medical Center La Raza, Instituto Mexicano del Seguro Social, México D.F. femenmor@servidor.unam.mx
Curiel-Pérez
M O
MO
Cárdenas-Tirado
H
H
Montero-González
P
P
Gutiérrez-Avila
C
C
Bravo-Ríos
L E
LE
Cárdenas-Cornejo
I
I
Normandía-Almeida
M A
MA
D000293:Adolescent; D001323:Autoantibodies / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000201:enzymology / Q000276:immunology*; D005260:Female; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006801:Humans; D007223:Infant; D008297:Male; D008800:Mexico
D001323:Autoantibodies; D005968:Glutamate Decarboxylase