Clinical, endocrine and metabolic studies in the kindred of familial partial lipodystrophy--a syndrome of insulin resistance.

OBJECTIVE: To study clinical, endocrine and metabolic profiles in the kindred of subjects with familial partial lipodystrophy (FPLD, Dunnigan type). MATERIAL AND METHODS: Twenty two relatives (10 males, 12 females), from an extended family with FPLD, were assessed for the phenotypic features, impaired glucose tolerance (IGT)/diabetes mellitus (DM), dyslipidemia and the presence of insulin resistance. Plasma glucose and serum lipids were measured using glucose oxidase and standard colorimetric methods. Serum insulin was estimated by radioimmunoassay. RESULTS: The age was 12 to 67 years, two being adolescents. Two of the 20 adults were overweight and eight were underweight; BMI (adults) was 15.5 to 28.5. Features of FPLD were evident among eight out of 12 women. This typical phenotype was not obvious in all 10 male members. Varying degree of Hirsuitism was observed in four of 12 women, acanthosis nigricans in 11 out of 22 members and skin tags were present in only eight of 22; hypertension in six members and diabetes in four. Eleven members had either impaired glucose tolerance (IGT) (n=7), or DM (n=4). Ten of 20 members showed hyperinsulinemic response on oral glucose tolerance test (OGTT). Dyslipidemia was present in 13 family members. CONCLUSION: The majority (2/3rd) of female members showed typical phenotypic features of FPLD, with a clustering of cardiovascular risk factors and insulin resistance syndrome. More than half the men without phenotypic features of FPLD had either IGT/DM, dyslipidemia, hypertension or cardiovascular disease.

Serum leptin concentrations in hyperinsulinemia in the sets of obese, lipodystrophic and/or non-obese patients.

OBJECTIVE: To study the relationship between serum leptin and circulating insulin under basal and in response to oral glucose administration in hyperinsulinemic patients with or without obesity. MATERIAL AND METHOD: Fifteen female patients of known hyperinsulinemia provided material for the study. Leptin and insulin in sera were estimated by radioimmunoassay methods. RESULTS: Eight of the 15 hyperinsulinemic patients with high body mass index (BMI) (31 +/- 0.94 kg/m2) had significantly (p < 0.01) elevated serum leptin concentrations (26.1 +/- 2 ng/ml) as compared to the levels in the remaining seven non-obese hyperinsulinemic patients with BMI of 20 +/- 1.0 kg/m2; their mean levels of serum leptin were low 5.7 +/- 1.1 ng/ml. Four of the latter group had face-sparing partial lipodystrophy. The mean circulating leptin concentrations in the control group of seven healthy normoinsulinemic and regularly menstruating women with normal BMI (19 +/- 0.95 kg/m2) were 13.7 +/- 1.8 ng/ml. DISCUSSION: The results of the present study in 15 hyperinsulinemic patients show that circulating levels of leptin are not related to serum insulin. However, there was a positive correlation with BMI. An interesting observation of the study is that, notwithstanding the normal BMI, the group of hyperinsulinemic patients with face-sparing partial lipodystrophy had the lowest levels of circulating leptin concentrations. They were closer to the values found in prepubertal girls.