Rabconnectin-3α and the control of puberty Human genetics shows that low levels of rabconnectin-3α cause a loss of the neurons that produce gonadotropin-releasing hormone, revealing a new mechanism for incomplete puberty and infertility.

Context: Recently, in a 4-month proof-of-concept trial, beneficial metabolic effects were reported in non-diabetic children with Berardinelli-Seip congenital lipodystrophy (BSCL); this information prompted us to hypothesize that long-term leptin-replacement therapy might improve or reverse the early complications of the disease in these patients. Patients and methods: A 28-month trial was implemented in eight patients. Efficacy assessment was based on a decrease in serum triglyceride concentrations, and/or a decrease in liver volume and/or an increase in insulin sensitivity of at least 30% respectively. The response was defined as follows: total (3/3 positive criteria), partial (1 or 2/3), or negative (0/3). Anti-leptin antibodies were measured with a radiobinding assay, and a neutralizing effect was assessed in primary cultures of embryonic neurons incubated with an apoptotic agent (N-methyl-D-aspartate) and the patient serum, with or without leptin. Results: A negative or partial response to treatment was observed in five of eight patients even when leptin dosages were increased. A displaceable leptin binding was detectable in all patients after 2 months of treatment. At 28 months, binding was higher in the patients with a negative response than in the total responders, and it paralleled both the increase in leptin dosage and serum leptin concentrations. Co-incubation of embryonic neurons with serum from two patients with a negative response inhibited the neuroprotective effect of leptin. Conclusion: Under leptin therapy, patients with BSCL may develop a resistance to leptin, which could be partly of immunological origin, blunting the previously reported beneficial effects.

Since its discovery in 1997, knowledge about the SHOX gene (Short stature HOmeoboX-containing gene) has rapidly advanced. Although originally described as causing idiopathic short stature, SHOX mutations are also responsible for growth retardation in Léri-Weill dyschondrosteosis, Langer mesomelic dysplasia and Turner syndrome. Furthermore, SHOX has a broad functional scope and leads to a variety of different morphological-skeletal stigmata associated with these syndromes. This article reviews clinical and molecular data associated SHOX gene defects. Functional ongoing studies are expected to improve our understanding of the SHOX gene as comprising part of a genetic process responsible for normal growth and bone development.

A percentage of 21.2% NCCAH patients showed inadequate cortisol response to ACTH stimulation. In these subjects, the discontinuation of treatment on completion of growth deserves consideration.

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of Cushing syndrome in children, often occurring in association with Carney complex. We report a case of Cushing syndrome due to isolated non-familial PPNAD. The child presented with typical clinical characteristics, growth retardation and obesity. Liddle ' s test was positive but micronodular appearance was not evident on CT scan and MRI; selective venous sampling revealed higher cortisol concentrations in the right adrenal vein. The patient underwent a laparoscopic right adrenalectomy. Postoperatively, hypercortisolism signs disappeared but after the second year a slight increase in urinary cortisol was noted and the patient developed osteopenia. Although signifi cant catch-up growth occurred postoperatively, height did not normalize over the next 2 years. When she entered puberty, treatment with a luteinizing-hormone-releasing hormone agonist was initiated and growth hormone was added. Almost 5 years later a left adrenalectomy was also performed. Thereafter, complete disease remission was observed, the patient ' s growth accelerated and her osteopenia reversed.