Growth and pubertal disorders in neurofibromatosis type 1.

The first textbook of Pediatric Endocrinology in the early 1950s reported an association of neurofibromatosis type 1 (NF1) and precocious puberty (PP) and/or short stature. Recent studies have indicated that children with NF1 grow normally until puberty; thereafter height velocity and relative height (SDS or percentiles) decreases with respect to healthy peers, reaching a mean adult height close to the 25th percentile for the general population. Moreover, the percentage of patients with true short stature (<3rd percentile) increases from childhood (5%) to late puberty (20-30% in literature, 18% in our study), and final height is significantly below the genetic target and predicted adult height calculated just before or at the beginning of puberty. Finally, among the shortest patients (<10th percentile) there is a high incidence of severe complications, such as CNS tumors, huge plexiform neurofibromas and severe scoliosis. Precocious puberty is a frequent complication of NF1, and occurs mainly in association with optic pathway tumors (OPT); however, occasionally it has been reported in the absence of optic gliomas, probably with a similar incidence as in the general population. GnRH agonist therapy must be decided individually as in some patients further growth could be normal and/or treatment would not improve final height. In the presence of early pubertal signs, an OPT must be ruled out. In addition to PP, delayed puberty has been frequently reported in NF1. In a study of 123 girls with NF1, we found that the mean age at menarche (13.0 +/- 1.9 yr) was later than in their mothers (12.7 +/- 1.4 yr) and in the general population (12.4 +/- 1.2 yr; p <0.05), with a very high incidence of delayed menarche (>2 SD): 16% vs 6.8% (mothers) vs 3.4% (controls) (p <0.01). In conclusion, growth and puberty present unusual patterns in NF1, often with true pathological findings increasing medical and psychological problems.

[Neonatal diabetes, heterogeneous syndrome]. / Diabete neonatale, sindrome eterogenea.

Neonatal diabetes (ND) is a rare condition of hyperglycaemia which occurs, generally, within the first month of life, requires insulin therapy and lasts more than two weeks. The pathogenesis is uncertain and the different clinical variants are heterogeneous; both a "permanent" and a "transient" form of ND exist. We report the clinical history of three neonates (A.L., A.B. and V.I.) in which a tout-court diagnosis of ND was done; the follow-up allowed us to reevaluate the initial diagnoses and suppose different ethiopathogenic mechanisms. Clinical observations, insulin requirement and biochemical data obtained during the years of follow-up allowed to distinguish three different situations: a "permanent" ND (A.L.), a "transient-recurrent" ND (A.B.), and a Maturity Onset Diabetes of the Young (MODY) (V.I.).