Our retrospective analysis of growth and pubertal development includes 109 children and adults with meningomyelocele (MMC) (52 M, 57 F) aged 3.2-21.0 years (median 8.9 years). Anthropometric data, growth-retarding factors and data on pubertal development were analysed in comparison to the normal population using standards from Prader et al. (1). The results (mean +/- SD) were as follows. Fifty patients (46.8%) had short stature (height SDS for chronological age (SDS CA) < -2). The supine length was influenced by the level of the lesion (height SDS CA: > or = L2 -3.13 +/- 1.62, < or = S2 -0.46 +/- 1.27), ambulatory status, skeletal deformities and pubertal stage. The mean adult height (n = 15, age 16.1-21.0 years) measured 141.3 cm for women (height SDS CA -3.83 +/- 1.79) and 159.2 cm for men (height SDS CA -2.27 +/- 1.81). In 82.6% of the subjects (n = 90), arm spans were within the normal range. Reduced arm spans (SDS < -2) as found in 19 patients (17.4%) with short stature (mean height SDS CA -3.29 +/- 1.29) may be caused by factors other than neurological lesions and skeletal deformities, and require further endocrinological studies. Out of 27 pubertal patients, central precocious puberty was diagnosed in five girls. The stages of puberty in MMC girls developed earlier than expected for the age-related group.

Neural tube defects (NTD) are among the most common congenital malformations in humans. The current view is that there are no major genes causing NTDs, but combinations of sequence variants in different genes have additive effects on determining the malformation. Therefore it is important to identify such sequence variants to get a better understanding of NTD pathogenesis. Studies on animal models have shown that BMP4 and NOG are involved in the patterning of the neural tube. We therefore performed a single-strand conformation analysis (SSCA) mutation screen for both genes in 179 spina bifida aperta (SBA) patients. Our SSCA screen revealed four missense mutations in BMP4 and one in NOG. It is likely that these mutations have acted together with other gene variants in independently segregating loci as susceptibility factors in these SBA cases. In addition, a case-control association study provides evidence for a genotype disequilibrium of BMP4 polymorphism 455T?C (V152A) in exon 5. The frequency of the heterozygous 455TC genotype is lower in cases than in controls (nominal P=0.017), although allele frequencies are similar in both groups. A possible explanation for this finding might be that BMP4 455TC heterozygosity at this site is a protective factor in the normal population, although this hypothesis cannot be proven to date.

In patients with myelomeningocele (MMC), growth is influenced by a large number of growth‐retarding factors due to the neurological defect. Moreover, endocrine disorders have been found to contribute to short stature in MMC patients. Central precocious puberty (CPP) is a common problem. Due to growth disturbances and difficulties in obtaining standardized measurements, MMC patients have been excluded from gonadotropin‐releasing hormone (GnRH) analogue studies in the past. We report on eight patients (six female, two male) with MMC, hydrocephalus, and CPP who were treated with GnRH analogues: triptorelin intramuscularly (N=5) or leuprorelin subcutaneously (N=3). Auxological data and hormone levels were assessed before treatment and every 6 months during treatment. The median chronological ages (CA) at the start of treatment were 8.6 years (females) and 8.4 years (males). Bone age (BA) was accelerated in all cases prior to treatment and two girls were already menstruating. Elevated gonadotropin serum levels and sex steroid levels decreased during treatment, although no complete suppression to prepubertal levels was reached. Progression of pubertal development and menses stopped in all patients. The tempo of BA acceleration (ΔBA:ΔCA) decreased, but no significant improvement in height standard deviation score BA and predicted adult height resulted. No side effects during treatment were observed. CPP in MMC patients has to be considered as early as possible to enable an early diagnosis and corresponding treatment. Further prospective studies on the effects of GnRH analogues in MMC patients are necessary.

Arm span, serum IGF-1 and IGFBP-3 levels are estimated to be appropriate screening parameters for GHD in patients with MMC. Initiating growth hormone therapy should be considered not only according to endocrine findings but also with respect to neurological and orthopaedic anomalies.

Although several new genetic variants were found in TFAP2 and MSX2, no statistically significant association was found between NTD cases and the new alleles or their combinations. Further studies are necessary to finally decide if these gene variants may have acted as susceptibility factors in our individual cases.