Multiples of Median-Transformed, Normalized Reference Ranges of Steroid Profiling Data Independent of Age, Sex, and Units.

BACKGROUND/AIMS: The high complexity of pediatric reference ranges across age, sex, and units impairs clinical application and comparability of steroid hormone data, e.g., in congenital adrenal hyperplasia (CAH). We developed a multiples-of-median (MoM) normalization tool to overcome this major drawback in pediatric endocrinology. METHODS: Liquid chromatography tandem mass spectrometry data comprising 10 steroid hormones representing 905 controls (555 males, 350 females, 0 to > 16 years) from 2 previous datasets were MoM transformed across age and sex. Twenty-three genetically proven CAH patients were included (21-hydroxylase deficiency [21OHD], n = 19; 11ß-hydroxylase deficiency [11OHD], n = 4). MoM cutoffs for single steroids predicting 21OHD and 11OHD were computed and validated through new, independent patients (21OHD, n = 8; adrenal cortical carcinoma, n = 6; obesity, n = 40). RESULTS: 21OHD and 11OHD patients showed disease-typical, easily recognizable MoM patterns independent of age, sex, and concentration units. Two single-steroid cutoffs indicated 21OHD: 3.87 MoM for 17-hydroxyprogesterone (100% sensitivity and 98.83% specificity) and 12.28 MoM for 21-deoxycortisol (94.74% sensitivity and 100% specificity). A cutoff of 13.18 MoM for 11-deoxycortisol indicated 11OHD (100% sensitivity and 100% specificity). CONCLUSIONS: Age- and sex-independent MoMs are straightforward for a clinically relevant display of multi-steroid patterns. In addition, defined single-steroid MoMs can serve alone as predictors of 21OHD and 11OHD. Finally, MoM transformation offers substantial enhancement of routine and scientific steroid hormone data exchange due to improved comparability.

Is growth without IGF1 possible? A case report.

According to the growth hormone - insulin-like growth factor 1 axis (GH/IGF1 axis) theory, the actions of GH on promoting growth are mediated by IGF1. In the blood, IGF1, insulin-like growth factor 1 binding protein 3 (IGFBP3) and acid-labile subunit (ALS) form ternary complexes, hence the accumulation of IGF1. We report a case of 10-year-old male with short stature due to GH deficiency diagnosed with hypopituitarism. Therapy with recombinant human GH (rhGH) was initiated at 11 years and 4 months. After twenty three months on treatment clinical effects were as follows: increase in the patient's height by 19.2 cm (initial height 12.4 cm vs. 140.6 cm; hSDS -4.35 vs. -2.7; predicted adult height 176 cm vs. 182 cm, respectively). Despite good clinical response to the therapy, serum levels of IGF1 and IGFBP3 remained diminished: IGF1 - 28 ng/ml initially, vs. 23 ng/ml 19 months on therapy and IGFBP3 - 1116 ng/ml initially, vs. 1888 ng/ml after 11 months on therapy. We attempt to justify this phenomenon by reconsidering the IGF1-independent GH actions, assessing the endocrine role of hepatic IGF1 in comparison to the autocrine/paracrine role of its bone tissue fraction, and evaluating the functions of ALS. The exact explanation for the positive response to rhGH treatment without the expected increase in IGF1 in our patient remains unknown. Serum levels of IGF1 and IGFBP3 seem not always to be reliable markers of the response to rhGH treatment in GH-deficient patients.

A novel mutation in the NR0B1 (DAX1) gene in a large family with two boys affected by congenital adrenal hypoplasia.

OBJECTIVE: X-linked Adrenal Hypoplasia Congenita (AHC) is a rare disorder caused by mutations in NR0B1 (DAX1) gene. DESIGN: We present two boys (cousins) with AHC who came to our attention at the age of 10 days and 15 days, respectively, in a life-threatening state. Laboratory studies in their neonatal periods showed hyponatremia and hyperkalemia. Primary adrenal insufficiency was confirmed, with severely low serum cortisol levels and high plasma ACTH levels. Hydrocortisone therapy with additional saline and glucose infusions were started immediately. Two exons of the NR0B1 (DAX1) gene were amplified using PCR and directly sequenced. RESULTS: Molecular analysis of the NR0B1 (DAX1) gene revealed a novel mutation, c.315G>A (p.W105X) in exon 1, resulting in the formation of a premature stop codon. Further studies showed that mothers, the maternal grandmother and two of six maternal great aunts were heterozygotes for the mutation. However, the mutation was absent in the maternal great-grandmother. CONCLUSIONS: We show that NR0B1 (DAX1) gene analysis is of great importance for the confirmation of the clinical diagnosis of AHC and highlights the role of genetic counseling for families of AHC patients. The absence of a somatic mutation in the great-grandmother suggests gonadal mosaicism as the mechanism for transmission of the NR0B1 (DAX1) mutation in this family.