Neonatal diabetes mellitus: chromosomal analysis in transient and permanent cases.
OBJECTIVE
To describe a large cohort of patients with transient neonatal diabetes mellitus (TNDM) and permanent neonatal diabetes mellitus (PNDM), and to investigate whether chromosome 6 analysis helps to distinguish TNDM from PNDM.


METHODS
Patients with TNDM (n = 29) (insulin therapy for <3 years) and 21 with PNDM were identified through a nationwide study.


RESULTS
Although patients with PNDM were less likely to have had intrauterine growth restriction (36% vs 74% for TNDM, P <.006), were older at diagnosis (median: 27 vs 6 days, P <.01), and had higher initial insulin requirements (1.4 U/kg/day vs 0.6 U/kg/day, P <.006), no clinical features were reliable in distinguishing PNDM from TNDM on an individual case basis. Permanent insulin-dependent diabetes developed in 5 TNDM patients after 8 years of age, emphasizing the need for prolonged follow-up. Among the 19 TNDM patients tested, two had paternal isodisomy of chromosome 6, seven from 4 families had paternally-derived trisomy of the 6q region, and two had a methylation defect in the 6q24 region. No chromosome 6 anomalies were found in the 9 PNDM patients tested.


CONCLUSIONS
When present, a chromosome 6 abnormality is strongly in favor of the "transient" form of the disease.
Metz
Chantal
C
Department of Pediatrics, Hôpital Morvan, Brest.
Cavé
Hélène
H
Bertrand
Anne Marie
AM
Deffert
Christine
C
Gueguen-Giroux
Béatrice
B
Czernichow
Paul
P
Polak
Michel
M
D001724:Birth Weight; D001786:Blood Glucose / Q000378:metabolism; D002869:Chromosome Aberrations; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000151:congenital* / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics*; D005192:Family Health; D005260:Female; D005500:Follow-Up Studies; D005602:France; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D005865:Gestational Age; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007223:Infant; D007229:Infant Welfare; D007231:Infant, Newborn; D007328:Insulin / Q000097:blood / Q000627:therapeutic use; D008297:Male; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin