Inhibin B (InhB) levels, as measured by a newly developed ELISA, in the assessment of testicular function in normal males and in newborns and infants with Congenital Multiple Pituitary Hormone Deficiency (CMPHD)

CAMPO S; LORETI N; D. BRASLAVSKY; GRINSPON R; AMBAO , VERONICA; BEDECARRÁS , PATRICIA; MARIA G. ROPELATO; REY RA; BERGADÁ , IGNACIO

Glasgow

Congreso; 50th Annual Meeting of the European Society for Paediatric Endocrinology (ESPE; 2011

European Society for Paediatric Endocrinology (ESPE

Background: In newborn males CMPHD, a life-threatening condition, can be suspected by signs of hypogonadism. InhB has been a valuable tool to assess testicular function from birth to adulthood. A newly developed assay, not requiring sample pre-treatment step, has become available but data on reference levels and its applicability in gonadal dysfunctions are lacking.In newborn males CMPHD, a life-threatening condition, can be suspected by signs of hypogonadism. InhB has been a valuable tool to assess testicular function from birth to adulthood. A newly developed assay, not requiring sample pre-treatment step, has become available but data on reference levels and its applicability in gonadal dysfunctions are lacking. Objective: Our aim was to establish: a) the normal range of inhB levels usingOur aim was to establish: a) the normal range of inhB levels using an active® Inhibin B Gen II ELISA (Beckman Coulter, USA) in boys from birth to advanced puberty and b) the usefulness of InhB in the diagnosis of males with CMPHD. Methods: 219 normal males and 11 boys with CMPHD aged 1-6 months were included. Serum levels of InhB were determined using Gen II and the219 normal males and 11 boys with CMPHD aged 1-6 months were included. Serum levels of InhB were determined using Gen II and the previously used Oxford Bio-Innovation (OBI) ELISAs. AMH, testosterone (T) and gonadotrophins were also measured. Results: Serum InhB was 164.8±65.7 pg/mL (mean ±SD) in the 0-2 yr group; then decreased to 77.1±40.2 pg/mL between 2 and 9 yr. InhB was always above the assay’s detection limit. During puberty, peak levels were attained atSerum InhB was 164.8±65.7 pg/mL (mean ±SD) in the 0-2 yr group; then decreased to 77.1±40.2 pg/mL between 2 and 9 yr. InhB was always above the assay’s detection limit. During puberty, peak levels were attained at Tanner stage II (TII) (195.1±70.2) with no significant changes thereafter: TIII: 198±64.9; TIV: 195.4±53.9 and TV: 222.9±69.7. Testicular volume and inhB positively correlated (r=0.64, p< 0.001). A good correlation between results from Gen II ELISA and the previously used Oxford Bio-Innovation (OBI) method was found: r=0.81, p<0.0001. Seven of 11 boys with CMPHD had InhB below -2 SDS, in coincidence with AMH, T and gonadotrophins below reference values, indicating congenital hypogonadism. Conclusions: Gen II ELISA showed similar ontogenic changes in serum InhB to those described with the OBI assay. Low InhB appears to be a helpful tool for the diagnosis of hypogonadism in newborns and infants with CMPHD.Gen II ELISA showed similar ontogenic changes in serum InhB to those described with the OBI assay. Low InhB appears to be a helpful tool for the diagnosis of hypogonadism in newborns and infants with CMPHD.