Fasting Blood Glucose (Bg) Levels in the Latent Period (Lp) of Iddm in Children

Abstract

ELATION WITH GH SECRETION AFTER TRH ADMINISTRATION. A N D ADOLESCENTS.The frequency of GH elevation observed in subjects with IDDM prompted us to look for pituitary autoantibodies. An indirect immunofluorescence technique utilizing human and guinea pig hypophysis was used to detect their presence in GH, TSII, and prolactin pituitary cells. Studies are now in progress to discriminate these specific endocrine cells autoantibodies. 26 subjects (12 boys, 14 girls, ages 7-20, mean age 12 1 yr) were tested after TRtl administration (7 pg/kg i.v., max. 200 pg). In controls, none had a significant response of plasma Gti as defined by an increase to at least twice the baseline levels and greater than 5 ng/ml. In IDDM children, a significant GH elevation was observed in 17 of 26 cases ( 9 girls, 8 boys) with a mean + SE level of 17.1 + 2.9 ng/ml (range 7.2 -39 ng/ml) (p<0.02 witE normal). Among th; responders to TRH, 14/17 had positive serum pituitary autoantibodies, while in the 9 children with no GH response to TRH, 7/9 had a negative determination. However, it is of interest to note that all patients except one had positive islet-cell antibodies in their serum In conclusion, these results are in agreement with the known paradoxical response of GH after TRH in IDDM patients, but not with the lower incidence reported in adult females. In addition, the study of pituitary autoimmunity could partly explain the changes in GH secretion observed in IDDM patients. Breakdown o f ORB i s reported as o n e o f t h e earliest retinal c h a n g e s i n adult diabetic patients (Cunha-Vaz.lg75). I n t h i s s t u d y w e investigated u h e t h e r vitreous fluorophotometry (VFPT) may permit t h e detection similar c h a n g e s in young patients.T h e permeability o f ORB w a s examined by V F P H i n 3 2 young diabetic patienis (8.4-20 y r s old) a n d i n 1 0 non-diabetic subjects o f same age. A11 patients had normal fundi a n d uere treated uith insulin injection t w i c e a day. V FASTING BLOOD GLUCOSE (BG) LEVELS IN THE LATENT PERIOD (LP) OF IDWM IN CHILDREN.We retrospectively analyzed the occasional fasting BG concentration o f 21 children and OGTT o f 7 subjects who developed IDDM 60-8 months later. Approaching symptomatic diabetes the fastlng BG levels (72-115 mg/dl) progressively increased with a r-value o f 0.68(p<O.OG5) and the peak insulin releasc at OGTT (40-26 uU/ml) dcclined in a similar linear manner (r=0.97;p<0.01). Abnormal UG elevations in response to OGTT have been noticed in all subjects at 6 0 min. ( > 180 mg/dl)and in 3 of them also at 180 min (> 140 mg/dl);glycosuria appeared in 2 subjects.In spite of these abnormalities BG levels were not further controlled before the overt onset o f IDDM. These retrospective data (rarely avalla ble in the PL o f IDDM in children) confirm that the abrupt clinical onset of diabetes may b e preceeded b y a long period of abnormal BG levels and insulin secretor y capacity. We suggest that monitoring of these parameters may constitute an effective and non-expensive mcasure to id...