The National Institutes of Health Consensus Development Program convened surgeons, endocrinologists, pathologists, biostatisticians, radiologists, oncologists, and other health care professionals, as well as members of the general public, to address the causes, prevalence, and natural history of clinically inapparent adrenal masses, or "incidentalomas"; the appropriate evaluation and treatment of such masses; and directions for future research. Improvements in abdominal imaging techniques have increased detection of adrenal incidentalomas, and because the prevalence of these masses increases with age, appropriate management of adrenal tumors will be a growing challenge in our aging society. To address six predetermined questions, the 12-member nonfederal, nonadvocate state-of-the-science panel heard presentations from 21 experts in adrenal incidentalomas and consulted a systematic review of medical literature on the topic provided by the Agency for Healthcare Research and Quality and an extensive bibliography developed by the National Library of Medicine. The panel recommended a 1-mg dexamethasone suppression test and measurement of plasma-free metanephrines for all patients with an adrenal incidentaloma; additional measurement of serum potassium and plasma aldosterone concentration-plasma renin activity ratio for patients with hypertension; and surgery for patients with biochemical evidence of pheochromocytoma, patients with tumors greater than 6 cm, and patients with tumors greater than 4 cm who also meet other criteria. The panel also advocated a multidisciplinary approach to managing adrenal incidentalomas. The statement is an independent report of the panel and is not a policy statement of the National Institutes of Health or the federal government.
The aromatase enzyme complex catalyzes the conversion of androgens to estrogens in a wide variety of tissues, including the ovary, testis, placenta, brain, and adipose tissue. Only a single human gene encoding aromatase P450 (CYP19) has been isolated; tissue-specific regulation is controlled in part by alternative promoters in a tissue-specific manner. We report a novel mutation in the CYP19 gene in a sister and brother. The 28-yr-old XX proband, followed since infancy, exhibited the cardinal features of the aromatase deficiency syndrome as recently defined. She had nonadrenal female pseudohermaphrodism at birth and underwent repair of the external genitalia, including a clitorectomy. At the age of puberty, she developed progressive signs of virilization, pubertal failure with no signs of estrogen action, hypergonadotropic hypogonadism, polycystic ovaries on pelvic sonography, and tall stature. The basal concentrations of plasma testosterone, androstenedione, and 17-hydroxyprogesterone were elevated, whereas plasma estradiol was low. Cyst fluid from the polycystic ovaries had a strikingly abnormal ratio of androstenedione and testosterone to estradiol and estrone. Hormone replacement therapy led to breast development, menses, resolution of ovarian cysts, and suppression of the elevated FSH and LH values. Her adult height is 177.6 cm (+2.5 SD). Her only sibling, an XY male, was studied at 24 yr of age. During both pregnancies, the mother exhibited signs of progressive virilization that regressed postpartum. The height of the brother was 204 cm (+3.7 SD) with eunuchoid skeletal proportions, and the weight was 135.1 kg (+2.1 SD). He was sexually fully mature and had macroorchidism. The plasma concentrations of testosterone (2015 ng/dL), 5 alpha-dihydrotestosterone (125 ng/dL), and androstenedione (335 ng/dL) were elevated; estradiol and estrone levels were less than 7 pg/mL. Plasma FSH and LH concentrations were more than 3 times the mean value. Plasma PRL was low; serum insulin-like growth factor I and GH-binding protein were normal. The bone age was 14 yr at a chronological age of 24 3/12 yr. Striking osteopenia was noted at the wrist. Bone mineral densitometric indexes of the lumbar spine (cancellous bone) and distal radius (cortical bone) were consistent with osteoporosis; the distal radius was -4.7 SD below the mean value for age- and sex-matched normal men; indexes of bone turnover were increased. Hyperinsulinemia, increased serum total and low density lipoprotein cholesterol, and triglycerides and decreased high density lipoprotein cholesterol were detected.(ABSTRACT TRUNCATED AT 400 WORDS)
The fundamental aspects of the hypothalamic luteinizing hormone-releasing hormone (LHRH)
Recent developments have advanced our knowledge of the role of estrogen in the male. Studies of the mutations in CYP19, the gene encoding aromatase, in six females and two males and a mutant estrogen receptor alpha in a man are described. These observations provide illuminating new insights into the critical role of estrogen in the male (as well as female) in the pubertal growth spurt and skeletal maturation, and in the importance of estrogen sufficiency in the accrual and maintenance of bone mass. The weight of evidence supports an effect of androgens on the latter processes, but this effect has not been quantitated. There is a discordance in the estrogen-deficient male between skeletal growth and skeletal maturation and the accrual of bone mass and density. Estrogen synthesis by the testis is limited before puberty, and estrogen deficiency does not affect the age of pubertal onset. Estrogen deficiency in men leads to hypergonadotropism, macroorchidism, and increased testosterone levels. Estrogen lack has a significant effect on carbohydrate and lipid metabolism, and estrogen resistance was associated with evidence of premature coronary atherosclerosis in a man. These observations have highlighted the role of extraglandular estrogen synthesis and intracrine and paracrine actions. In the human, in contrast to nonprimate vertebrates, aromatase deficiency and estrogen resistance (alpha) does not seem to affect gender identity or psychosexual development. The clinical repercussions of mutations in CYP19 on the fetal-placental unit have highlighted the major role of placental aromatase in the protection of the female fetus from androgen excess, thus preventing androgen-induced pseudohermaphrodism and virilization of the mother. These features are compared with the virilization that occurs in utero in the female spotted hyena. The novel features of the aromatase deficiency syndrome in the affected female--in the fetus, during childhood, and at puberty--are discussed, including virilization at puberty and development of polycystic ovaries. The severity of the syndrome correlates with the severity of impairment of aromatase formation in expression systems. Finally, the structural consequences of missense mutations in CYP19 are described in accordance with a model of the structure of human aromatase.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.