Severe insulin resistance contrasting with mild anthropometric changes in the adipose tissue of HIV-infected children with lipohypertrophy.

BACKGROUND: The HIV-associated lipodystrophic syndrome (HIV-LDS) combines redistribution of fat mass with insulin resistance and hyperlipidemia. We have previously reported that HIV-LDS prevails in children in a comparable pattern as in adults. The metabolic activity itself of the lipodystrophic adipose tissue in HIV infection has been poorly studied. AIM AND METHODS: To assess in situ the insulin sensitivity of the lipohypertrophic subcutaneous abdominal adipose tissue using the microdialysis technique in HIV-infected children. Insulin sensitivity, assessed by the inhibition of glycerol release, was measured in the abdominal subcutaneous adipose tissue during a standard oral glucose tolerance test (OGTT) in six HIV-infected children under multi-therapy with abdominal lipohypertrophy (supra-iliac skinfold thickness >97th percentile) (HIV/LH+), in six obese children (obese group) and in eight HIV-infected children without lipodystrophy (HIV/LH-). RESULTS: Glucose tolerance was normal in all subjects. Mean insulin areas under the curve (IAUC) were significantly higher in the obese and HIV/LH+ groups than in HIV/LH- (8769+/-5429, 8161+/-4552 and 3618+/-2222 mU min l(-1), respectively; P=0.04 for the three groups comparison by the Kruskal-Wallis test), reflecting insulin resistance in the two former groups independent of a significant difference in percentage fat mass (37.2+/-4.7, 22.8+/-10.9 and 20.7+/-7.1%, respectively; P= 0.006). The crude inhibition of glycerol release, expressed as the relative change in dialysate glycerol concentration between baseline and 120 min, was not statistically different between the three groups (14% in obese, -38+/-14% in HIV/LH+ and -51+/-17% in HIV/LH- groups; P=0.3). The inhibition of glycerol release with respect to the circulating insulin level (expressed by IAUC) was similar in HIV/LH+ and obese groups (-6+/-5 x 10(-3) and -7+/-5 x 10(-3) l mU(-1) min(-1), respectively, P=0.4 for two-groups comparison by the U-Mann-Whitney test) and four-fold less than in the HIV/LH- group (-24+/-25 x 10(-3) l mU(-1) min(-1); P=0.02). CONCLUSION: These data argue in favor of insulin resistance in the adipose tissue of lipohypertrophies associated with HIV infection.

Nocturnal hypoglycemia in children and adolescents with insulin-dependent diabetes mellitus: prevalence and risk factors.

OBJECTIVES: To evaluate the prevalence and risk factors of nocturnal hypoglycemia (NH) in children and adolescents with insulin-dependent diabetes mellitus. STUDY DESIGN: A total of 150 patients, 87% of whom were receiving conventional therapy, were admitted to the hospital for one night. Blood glucose (BG) levels were measured hourly from 10 PM to 8 AM. RESULTS: The prevalence of NH was 47%; NH was asymptomatic in 49% of the cases. Risk factors were as follows: at least two episodes of severe hypoglycemia from onset of insulin-dependent diabetes mellitus (p = 0.0004), insulin dosage > 0.85 IU/kg per day (p = 0.02), more than 5% of BG measurements < or = 3.3 mmol/L during the last month of monitoring (p = 0.04). The risk decreased significantly with age (p = 0.0001). Both high predictive values and significant relative risk were found for BG thresholds < or = 5.2 mmol/L at dinner time (p < 0.0001) and < or = 6.7 mmol/L at 7 AM (p < 0.0001). When BG values at 10 PM were used, prediction of NH was weak. CONCLUSIONS: Nocturnal hypoglycemia occurred frequently in children and adolescents with insulin-dependent diabetes mellitus. Our study found risk factors that will help pediatricians to identify those children with a high risk of NH. Especially in these patients, counseling based on the BG values before dinner and early in the morning is indicated to reduce the prevalence of NH.

Subcutaneous or intramuscular injections of insulin in children. Are we injecting where we think we are?

OBJECTIVE: This study was designed to assess the insulin injection location in a group of children who had their injection according to their daily practice, thought to lead to subcutaneous injections. RESEARCH DESIGN AND METHODS: The location of the insulin deposit at the injection site was visualized using an ultrasound device. RESULTS: The exact insulin injection location could be localized, and 18 of 59 injections (30.5%) (one injection for each child) were in the intramuscular tissue. Of the children who had intramuscular injection, 15 of 18 were boys. The children who had an intramuscular injection had a significantly lower percentile of BMI (mean +/- SE: 47 +/- 8 vs. 72 +/- 4, P = 0.004), lower distance from skin surface to muscle fascia without a skinfold (5.6 +/- 0.6 vs. 11 +/- 0.7 mm, P < 0.0001), and a lower distance from skin surface to muscle fascia with a skinfold (8.1 +/- 0.9 vs. 15.9 +/- 0.8 mm, P < 0.0001) than children who had a subcutaneous insulin injection. CONCLUSIONS: We identified a group of children at risk for intramuscular insulin injections and that may deserve specific injection technique and advice.

Nasal pyriform aperture stenosis and absence of the anterior pituitary gland: report of two cases.

We describe two female infants with congenital nasal pyriform aperture stenosis and severe pituitary insufficiency. The anterior pituitary gland was undetectable with magnetic resonance imaging. Consanguinity of parents in both cases suggests autosomal recessive inheritance of this disorder. An early fetal developmental defect may explain this syndrome, which affects midline craniofacial structures. In patients with congenital pyriform aperture stenosis, magnetic resonance imaging of the brain and endocrine investigations should be performed for rapid diagnosis and treatment of the latter to avoid major neurologic complications.