ABSTRACT
BACKGROUND: Inhibin B is a hormone produced by the Sertoli cells that can provide important information for the investigation of disorders of sex development (DSD) with 46,XY karyotype. The aim of this study is to compare two enzyme-linked immunosorbent assay (ELISA) assays for dosage of serum inhibin B in patients with 46,XY DSD with normal testosterone secretion. METHODS: Twenty-nine patients with 46,XY DSD and normal testosterone secretion (partial androgen insensitivity syndrome [PAIS] [n=8]; 5α-reductase deficiency [n=7] and idiopathic 46,XY DSD [n=14]) were included. Molecular analysis of the AR and SRD5A2 genes were performed in all patients and the NR5A1 gene analysis in the idiopathic group. Measurements of inhibin B were performed by two second-generation ELISA assays (Beckman-Coulter and AnshLabs). Assays were compared using the interclass correlation coefficient (ICC) and the Bland-Altman method. RESULTS: ICC was 0.915 [95% confidence interval (CI): 0.828-0.959], however, a discrepancy was observed between trials, which is more evident among higher values when analyzed by the Bland-Altman method. CONCLUSIONS: It is recommended to perform the inhibin B measurement always using the same ELISA kit when several evaluations are required for a specific patient.
Subject(s)
Disorder of Sex Development, 46,XY/blood , Enzyme-Linked Immunosorbent Assay , Inhibin-beta Subunits/blood , Testis/metabolism , Testosterone/metabolism , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/blood , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/deficiency , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/genetics , Adolescent , Adult , Androgen-Insensitivity Syndrome/blood , Androgen-Insensitivity Syndrome/diagnosis , Androgen-Insensitivity Syndrome/genetics , Androgen-Insensitivity Syndrome/physiopathology , Child , Child, Preschool , Diagnosis, Differential , Disorder of Sex Development, 46,XY/diagnosis , Disorder of Sex Development, 46,XY/genetics , Disorder of Sex Development, 46,XY/physiopathology , Hospitals, University , Humans , Hypospadias/blood , Hypospadias/diagnosis , Hypospadias/genetics , Hypospadias/physiopathology , Karyotype , Male , Membrane Proteins/genetics , Outpatient Clinics, Hospital , Receptors, Androgen/genetics , Reproducibility of Results , Severity of Illness Index , Steroid Metabolism, Inborn Errors/blood , Steroid Metabolism, Inborn Errors/diagnosis , Steroid Metabolism, Inborn Errors/genetics , Steroid Metabolism, Inborn Errors/physiopathology , Steroidogenic Factor 1/genetics , Testis/physiopathology , Young AdultABSTRACT
Objective. To evaluate diagnosis, age of referral, karyotype, and sex of rearing of cases with disorders of sex development (DSD) with ambiguous genitalia. Methods. Retrospective study during 23 years at outpatient clinic of a referral center. Results. There were 408 cases; 250 (61.3%) were 46,XY and 124 (30.4%) 46,XX and 34 (8.3%) had sex chromosomes abnormalities. 189 (46.3%) had 46,XY testicular DSD, 105 (25.7%) 46,XX ovarian DSD, 95 (23.3%) disorders of gonadal development (DGD), and 19 (4.7%) complex malformations. The main etiology of 46,XX ovarian DSD was salt-wasting 21-hydroxylase deficiency. In 46,XX and 46,XY groups, other malformations were observed. In the DGD group, 46,XY partial gonadal dysgenesis, mixed gonadal dysgenesis, and ovotesticular DSD were more frequent. Low birth weight was observed in 42 cases of idiopathic 46,XY testicular DSD. The average age at diagnosis was 31.7 months. The final sex of rearing was male in 238 cases and female in 170. Only 6.6% (27 cases) needed sex reassignment. Conclusions. In this large DSD sample with ambiguous genitalia, the 46,XY karyotype was the most frequent; in turn, congenital adrenal hyperplasia was the most frequent etiology. Malformations associated with DSD were common in all groups and low birth weight was associated with idiopathic 46,XY testicular DSD.
