BRAIN-STEM AUDITORY-EVOKED POTENTIAL, VISUAL-EVOKED POTENTIAL AND NERVE-CONDUCTION VELOCITY AND THEIR RELATION WITH HBA(1C) AND BETA(2)-MICROGLOBULIN IN CHILDREN WITH INSULIN-DEPENDENT DIABETES-MELLITUS

Brain stem auditory evoked response (BAER), visual evoked response (VE R) and nerve conduction velocities (NCV) were studied in 18 insulin-de pendent diabetic children between the ages of 3.5 and 16 years (mean 9 .0 +/- 3.2 years). The results were compared with those of age-matched controls. The VER latencies of the diabetic children in the right eye and left eye were significantly prolonged when compared with the cont rol group. NCV of n.peroneus and the latency of sensorial n.medianus w ere significantly impaired when compared with the control group. Altho ugh the latencies of waves III, IV and V of the right ear and the inte rpeak latencies of I-III, I-V, III-V of both ears were prolonged, the comparison with the control group was not significant. The beta2 micro globulin levels of the diabetic patients were significantly higher tha n those of the control group. There was a positive correlation between the beta2 microglobulin and the BAER interpeak latencies of wave III- V in both ears (r: 0.51 p < 0.01). There was also a positive correlati on between NCVs of n.peroneus and n.medianus (motor and sensorial) wit h beta2 microglobulin (r: 0.52 p < 0.01) and between VER latencies (r: 0.52 p < 0.01) of both eyes separately. In our study the prolonged la tencies of VER and BAER were detected in the absence of clinical abnor malities in visual and hearing systems. Due to our findings, we conclu de that prolongation of latencies of VER and BAER are mostly the first signs of central nervous system (CNS) involvement in insulin-dependen t diabetes, and the procedures are easy to perform as well as harmless to patients.