Influence of spironolactone on neonatal screening for congenital adrenal hyperplasia

• Published in: Archives of Disease in Childhood - Fetal and Neonatal Edition Vol. 81; no. 3; pp. F179 - F183
• Main Authors: Terai, Itaru, Yamano, Kimiaki, Ichihara, Naoshi, Arai, Junri, Kobayashi, Kunihiko
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health 01.11.1999; BMJ; BMJ Publishing Group LTD; BMJ Group
• Subjects: 17-alpha-Hydroxyprogesterone; 17-alpha-Hydroxyprogesterone - metabolism; 17α-hydroxyprogesterone; Adrenal Hyperplasia, Congenital; Adrenal Hyperplasia, Congenital - blood; Adrenal Hyperplasia, Congenital - diagnosis; Adrenals. Adrenal axis. Renin-angiotensin system (diseases); Biological and medical sciences; Blood; congenital adrenal hyperplasia; Diuretics; Diuretics - metabolism; Endocrinopathies; Enzyme-Linked Immunosorbent Assay; Enzymes; False Positive Reactions; Humans; Immunological methods for diagnosis and exploration; Immunopathology; Infant, Newborn; Laboratories; Liquid chromatography; Male; Medical sciences; Metabolites; Neonatal Screening; Neonatal Screening - methods; Non tumoral diseases. Target tissue resistance. Benign neoplasms; Original; Original article; Other methods; screening; Spironolactone; Spironolactone - metabolism; Japan; Endocrinopathy; Human; Adrenal cortex diseases; False positive; Hyperadrenocorticism; Medical screening; Enzymopathy; Congenital adrenal hyperplasia syndrome; Newborn; Treatment; Spironolactone; Adrenal gland diseases; ELISA assay
• ISSN: 1359-2998; 1468-2052
• DOI: 10.1136/fn.81.3.F179

AIM To determine if the diuretic spironolactone cross reacts with 17α-hydroxyprogesterone (17OHP) in an enzyme linked immunosorbent assay (ELISA) kit used for the mass screening of congenital adrenal hyperplasia. METHODS Concentrations of 17OHP on a blood filter paper disc were measured using an ELISA kit (kit C-7: ENZAPLATE N-17α -OHP-7; Chiron, Tokyo, Japan). The cross reactivity of spironolactone and its metabolites with 17OHP was determined. The concentrations of spironolactone and its metabolites in blood were measured using HPLC (high performance liquid chromatography). RESULTS Spironolactone cross reacted with 17OHP using kit C-7 (0.01%), by increasing 17OHP concentration in a dose dependent manner. The blood concentration of spironolactone and its metabolites was nearly 900 ng/ml, high enough to show an additive effect on the 17OHP concentration. About 12% of the false positive cases screened using the kit were due to the administration of spironolactone. CONCLUSIONS Spironolactone interferes with 17OHP concentrations, leading to false positive test results for CAH.