Richard J. Auchus

Steroidogenesis entails processes by which cholesterol is converted to biologically active steroid hormones. Whereas most endocrine texts discuss adrenal, ovarian, testicular, placental, and other steroidogenic processes in a gland-specific fashion, steroidogenesis is better understood as a single process that is repeated in each gland with cell-type-specific variations on a single theme. Thus, understanding steroidogenesis is rooted in an understanding of the biochemistry of the various steroidogenic enzymes and cofactors and the genes that encode them. The first and rate-limiting step in steroidogenesis is the conversion of cholesterol to pregnenolone by a single enzyme, P450scc (CYP11A1), but this enzymatically complex step is subject to multiple regulatory mechanisms, yielding finely tuned quantitative regulation. Qualitative regulation determining the type of steroid to be produced is mediated by many enzymes and cofactors. Steroidogenic enzymes fall into two groups: cytochrome P450 enzymes and hydroxysteroid dehydrogenases. A cytochrome P450 may be either type 1 (in mitochondria) or type 2 (in endoplasmic reticulum), and a hydroxysteroid dehydrogenase may belong to either the aldo-keto reductase or short-chain dehydrogenase/reductase families. The activities of these enzymes are modulated by posttranslational modifications and by cofactors, especially electron-donating redox partners. The elucidation of the precise roles of these various enzymes and cofactors has been greatly facilitated by identifying the genetic bases of rare disorders of steroidogenesis. Some enzymes not principally involved in steroidogenesis may also catalyze extraglandular steroidogenesis, modulating the phenotype expected to result from some mutations. Understanding steroidogenesis is of fundamental importance to understanding disorders of sexual differentiation, reproduction, fertility, hypertension, obesity, and physiological homeostasis.

The goal of this update regarding the diagnosis and care of persons with disorders of sex development (DSDs) is to address changes in the clinical approach since the 2005 Consensus Conference, since knowledge and viewpoints change. An effort was made to include representatives from a broad perspective including support and advocacy groups. The goal of patient care is focused upon the best possible quality of life (QoL). The field of DSD is continuously developing. An update on the clinical evaluation of infants and older individuals with ambiguous genitalia including perceptions regarding male or female assignment is discussed. Topics include biochemical and genetic assessment, the risk of germ cell tumor development, approaches to psychosocial and psychosexual well-being and an update on support groups. Open and on-going communication with patients and parents must involve full disclosure, with the recognition that, while DSD conditions are life-long, enhancement of the best possible outcome improves QoL. The evolution of diagnosis and care continues, while it is still impossible to predict gender development in an individual case with certainty. Such decisions and decisions regarding surgery during infancy that alters external genital anatomy or removes germ cells continue to carry risk.

Newborn screening Cost-effectiveness 1.1 We recommend that all newborn screening programs incorporate screening for congenital adrenal hyperplasia due to 21-hydroxylase deficiency. (1|s) 1.2 We recommend that first-tier screens use 17hydroxyprogesterone assays standardized to a common technology with norms stratified by gestational age. (1|s) Technical remark: Clinicians should be aware that immunoassays are still in use and remain a source of false-positive results. Specificity may be improved with organic extraction to remove cross-reacting substances. 1.3 We recommend that screening laboratories employ a second-tier screen by liquid chromatographytandem mass spectrometry in preference to all other

OBJECTIVE: The objective of the study was to evaluate the current state of clinical assays for total and free testosterone. PARTICIPANTS: The five participants were appointed by the Council of The Endocrine Society and charged with attaining the objective using published data and expert opinion. EVIDENCE: Data were gleaned from published sources via online databases (principally PubMed, Ovid MEDLINE, Google Scholar), the College of American Pathologists, and the clinical and laboratory experiences of the participants. CONSENSUS PROCESS: The statement was an effort of the committee and was reviewed in detail by each member. The Council of The Endocrine Society reviewed a late draft and made specific recommendations. CONCLUSIONS: Laboratory proficiency testing should be based on the ability to measure accurately and precisely samples containing known concentrations of testosterone, not only on agreement with others using the same method. When such standardization is in place, normative values for total and free testosterone should be established for both genders and children, taking into account the many variables that influence serum testosterone concentration.