Serum leptin and body composition in children with familial GH deficiency (GHD) due to a mutation in the growth hormone-releasing hormone (GHRH) receptor

OBJECTIVE: The relationship between GH, body composition and leptin in children remains ill-defined. We have therefore examined the impact of severe GH deficiency (GHD) due to a mutation in the GHRH receptor on serum leptin concentrations and body composition in childhood. PATIENTS: 12 affected children and young people (GHD) (4 M:8F, age 5.4-20.1 years, 8 Tanner stage (TS) 1-2, 4 TS 3-5) and 40 healthy controls (C) from the same region (13 M:27F, age 5.3-18.4 years, 20 TS 1-2, 20 TS 3-5). METHODS: Percent body fat was determined by infra-red interactance, from which the amounts of fat mass (FM, kg) and fat free mass (FFM, kg) were derived. Serum leptin concentrations were measured in a single fasted, morning serum sample and results expressed as a concentration and as leptin per unit fat mass (L/FM, ng/ml/kg). To control for differences in sex and pubertal maturation, leptin standard deviation scores (leptin SDS) were calculated using normative data from UK children. RESULTS: FFM was significantly lower in GHD children than in controls (TS 1-2 P < 0.05, TS 3-5 P < 0.001). FM did not differ significantly between the two groups. Serum leptin concentrations, leptin per unit fat mass and leptin SDS were significantly elevated in GHD children both peripubertal and pubertal compared with controls. Using all subjects, stepwise multiple linear regression with FM, FFM, age, puberty and sex as explanatory variables and leptin concentration as the dependent variable indicated that 59% of the variability in leptin could be accounted for by FM (+, 45%), FFM (-, 9%) and sex (+, 5%) (P < 0.001). However on inclusion of GH deficiency (coded GHD = 1, control = 2) as an explanatory variable 73% of the variability in leptin was explained by FM (+, 45%), GHD (-, 22%) and sex (+, 6%) (P < 0.001). CONCLUSIONS: These data indicate that severe GH deficiency in children is associated with elevated leptin concentrations, irrespective of sex or pubertal stage. This increase is not associated with differences in fat mass but is related to reduced fat free mass in GH deficiency. Furthermore in this population there may be an additional effect of GH deficiency on leptin, independent of the influences of sex and body composition.     

Fragmented QRS complexes not typical of a bundle branch block: a marker of greater myocardial perfusion tomography abnormalities in coronary artery disease.

BACKGROUND: Fragmented QRS (FQRS) complexes, not typical of a bundle branch block, are a marker of regional myocardial injury. The extent of stress myocardial perfusion imaging (MPI) abnormalities with FQRS patterns is not known. METHODS AND RESULTS: Twelve-lead electrocardiograms (ECGs) in 501 patients undergoing stress MPI were studied. FQRS was defined as a QRS duration of 120 milliseconds or less, with notches or slurs of QRS complexes, on 2 contiguous leads of a coronary artery territory. Abnormal MPI was defined as a regional summed stress score (SSS) and summed rest score (SRS) of 3 or greater based on a 17-segment model. Patients with a typical bundle (n = 26), paced rhythm (n = 2), and Q waves (n = 64) were excluded. Of the remaining 409 patients (mean age, 58 +/- 13 years; 52% male), 155 (38%) had FQRS on the ECG. FQRS patients had a higher mean SSS, SRS, and global summed difference score and a lower left ventricular ejection fraction (all P < .001), as well as greater regional stress MPI scar (69% vs 11%, P < .001). FQRS pattern sensitivity was 75% and specificity was 94% for a corresponding regional MPI scar. On logistic regression, SSS, SRS, summed difference score, left ventricular ejection fraction, and regional scar were univariate predictors of the FQRS pattern on the ECG (all P < .01), and any regional scar (odds ratio, 32; P < .001) was a multivariate predictor. CONCLUSIONS: FQRS complexes on an ECG are a marker of higher stress MPI perfusion and functional abnormalities. Regional FQRS patterns denote the presence of a greater corresponding focal regional myocardial scar on stress MPI.     

Chagas disease in rural areas of Chaco Province, Argentina: epidemiologic survey in humans, reservoirs, and vectors

We studied the seroprevalence of antibodies against Trypanosoma cruzi in the human population along with domiciliary infestation by triatomine bugs in an area endemic for Chagas disease in the Chaco Province of Argentina. In addition, we carried out parasitologic surveys in patients, dogs, wild mammals, and vectors. The mean seroprevalence in humans was 27.81% (109 of 392) and 24.14% (63 of 261) in 1-15-year-old children. The minimum domiciliary infestation rate was 13.33%, with certain areas reaching 53.85%. The prevalence was 15.09% (16 of 106) in dogs and 35.71% (10 of 28) in opossums. Infection with T. cruzi was detected in 30.10% (59 of 196) of the Triatoma infestans tested. Compared with nationwide studies, our data suggest that 1) there are zones requiring immediate sanitary action, and 2) nationwide estimates are based on very heterogeneous epidemiologic situations. This heterogeneity emphasizes the importance of in-depth studies of restricted areas to provide additional information for a better understanding of the present status of Chagas disease in Argentina.