Steroid Screening Tools Differentiating Nonclassical Congenital Adrenal Hyperplasia and Polycystic Ovary Syndrome.

PURPOSE: To analyze the performance of basal 17OH-progesterone (17OHP) levels versus the basal 17OHP/cortisol ratio in nonclassical congenital adrenal hyperplasia (NCAH) and polycystic ovary syndrome (PCOS) differential diagnosis. Basal 17OHP levels >10 ng/mL have been used to confirm NCAH diagnosis without the adrenocorticotropic hormone (ACTH) test; however, the optimal cutoff value is a matter of debate. METHODS: A cross-sectional study was performed at the endocrinology and gynecological endocrinology outpatient clinics of a tertiary hospital. A total of 361 patients with PCOS (age 25.0 ± 5.3 years) and 113 (age 19.0 ± 13.6 years) patients with NCAH were enrolled. Basal and ACTH-17OHP levels were measured by radioimmunoassay, and CYP21A2 molecular analysis was performed to confirm hormonal NCAH diagnosis. Receiver operating characteristic curve analysis compared basal 17OHP levels and the 17OHP/cortisol ratio between NCAH and PCOS patients. RESULTS: Basal 17OHP levels were higher in NCAH patients than in those with PCOS (8.85 [4.20-17.30] vs 1.00 [0.70-1.50] ng/mL; P < 0.0001), along with 17OHP/cortisol ratio (0.86 [0.47-1.5]) vs 0.12 [0.07-0.19]; P < 0.0001, respectively). Basal 17OHP levels and the 17OHP/cortisol ratio were strongly correlated in both groups (rho = 0.82; P < 0.0001). Areas under the curves for basal 17OHP levels (0.9528) and the 17OHP/cortisol ratio (0.9455) were not different to discriminate NCAH and PCOS (P > 0.05). Basal 17OHP level >5.4 ng/mL and 17OHP/cortisol ratio >2.90 had 100% specificity to identify NCAH. MAIN CONCLUSIONS: Basal 17OHP levels >5.4 ng/mL can be used to perform differential diagnoses between NCAH and PCOS, dismissing the ACTH test. The basal 17OHP/cortisol ratio was not superior to basal 17OHP levels in this scenario.

Post-receptor IGF1 insensitivity restricted to the MAPK pathway in a Silver-Russell syndrome patient with hypomethylation at the imprinting control region on chromosome 11.

BACKGROUND: Hypomethylation of the paternal imprinting center region 1 (ICR1) is the most frequent molecular cause of Silver-Russell syndrome (SRS). Clinical evidence suggests that patients with this epimutation have mild IGF1 insensitivity. OBJECTIVE: To assess in vitro IGF1 action in fibroblast culture from a patient with SRS and IGF1 insensitivity. METHODS: Fibroblast cultures from one patient with SRS due to ICR1 demethylation and controls were established. The SRS patient has severe growth failure, elevated IGF1 level, and poor growth rate during human recombinant GH treatment. IGF1 action was assessed by cell proliferation, AKT, and p42/44-MAPK phosphorylation. Gene expression was determined by real-time PCR. RESULTS: Despite normal IGF1R sequence and expression, fibroblast proliferation induced by IGF1 was 50% lower in SRS fibroblasts in comparison with controls. IGF1 and insulin promoted a p42/44-MAPK activation in SRS fibroblasts 40 and 36%, respectively, lower than that in control fibroblasts. On the other hand, p42/44-MAPK activation induced by EGF stimulation was only slightly reduced (75% in SRS fibroblasts in comparison with control), suggesting a general impairment in MAPK pathway with a greater impairment of the stimulation induced by insulin and IGF1 than by EGF. A PCR array analysis disclosed a defect in MAPK pathway characterized by an increase in DUSP4 and MEF2C gene expressions in patient fibroblasts. CONCLUSION: A post-receptor IGF1 insensitivity was characterized in one patient with SRS and ICR1 hypomethylation. Although based on one unique severely affected patient, these results raise an intriguing mechanism to explain the postnatal growth impairment observed in SRS patients that needs confirmation in larger cohorts.