Germinal cell aplasia: response of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone to LH/FSH-releasing hormone with histopathologic correlation

Synchronous Presentation of Autoimmune Hepatitis and Multiple Myeloma

Autoimmune hepatitis (AIH) is a rare immune-mediated disease predominantly seen in women and triggered by various environmental factors. Rarely, AIH can be triggered by an underlying malignancy. We report a woman in her 60s who presented with markedly abnormal liver biochemical tests. Serology was positive for anti-smooth muscle antibodies and a liver biopsy confirmed AIH. During the hospital course, she developed sepsis and acute renal failure requiring dialysis support. Serum protein electrophoresis (SPEP) showed a monoclonal IgG kappa protein of 1.92 g/dL and a bone marrow biopsy revealed 7% clonal plasma cells. She had lytic lesions on skeletal survey confirming the diagnosis of a coexisting multiple myeloma (MM). Given her markedly abnormal liver chemistries, we decided to treat the AIH first and use the steroids (an important anti-myeloma therapy) as a bridge to the specific treatment of the MM once her clinical condition improved. She was treated with oral prednisone and azathioprine for AIH. One month later, a marked improvement in liver biochemical test results was noted and she was started on oral ixazomib, lenalidomide and dexamethasone. She received palliative radiotherapy to the lumbar spine (L2), left femur, and ischium lesions. This case highlights a rare co-occurrence of AIH and MM, the underlying mechanism of which is unknown.

Rodent Leydig cell tumorigenesis: a review of the physiology, pathology, mechanisms, and relevance to humans

Leydig cells (LCs) are the cells of the testis that have as their primary function the production of testosterone. LCs are a common target of compounds tested in rodent carcinogenicity bioassays. The number of reviews on Leydig cell tumors (LCTs) has increased in recent years because of its common occurrence in rodent bioassays and the importance in assessing the relevance of this tumor type to humans. To date, there have been no comprehensive reviews to identify all the compounds that have been shown to induce LCTs in rodents or has any review systematically evaluated the epidemiology data to determine whether humans were at increased risk for developing LCTs from exposure to these agents. This review attempts to fill these deficiencies in the literature by comparing the cytology and ontogeny of the LC, as well as the endocrine and paracrine regulation of both normal and tumorigenic LCs. In addition, the pathology of LCTs in rodents and humans is compared, compounds that induce LC hyperplasia or tumors are enumerated, and the human relevance of chemical-induced LCTs is discussed. There are plausible mechanisms for the chemical induction of LCTs, as typified by agonists of estrogen, gonadotropin releasing hormone (GnRH), and dopamine receptors, androgen receptor antagonists, and inhibitors of 5alpha-reductase, testosterone biosynthesis, and aromatase. Most of these ultimately involve elevation in serum luteinizing hormone (LH) and/or LC responsiveness to LH as proximate mediators. It is expected that further work will uncover additional mechanisms by which LCTs may arise, especially the role of growth factors in modulating LC tumorigenesis. Regarding human relevance, the pathways for regulation of the hypothalamo-pituitary-testis (HPT) axis of rats and humans are similar, such that compounds that either decrease testosterone or estradiol levels or their recognition will increase LH levels. Hence, compounds that induce LCTs in rats by disruption of the HPT axis pose a risk to human health, except for possibly two classes of compounds (GnRH and dopamine agonists). Because GnRH and prolactin receptors are either not expressed or are expressed at very low levels in the testes in humans, the induction of LCTs in rats by GnRH and dopamine agonists would appear not to be relevant to humans; however, the potential relevance to humans of the remaining five pathways of LCT induction cannot be ruled out. Therefore, the central issue becomes what is the relative sensitivity between rat and human LCs in their response to increased LH levels; specifically, is the proliferative stimulus initiated by increased levels of LH attenuated, similar, or enhanced in human vs. rat LCs? There are several lines of evidence that suggest that human LCs are quantitatively less sensitive than rats in their proliferative response to LH, and hence in their sensitivity to chemically induced LCTs. This evidence includes the following: (1) the human incidence of LCTs is much lower than in rodents even when corrected for detection bias; (2) several comparative differences exist between rat and human LCs that may contribute, at least in part, to the greater susceptibility of the rat to both spontaneous and xenobiotic-induced LCTs; (3) endocrine disease states in man (such as androgen-insensitivity syndrome and familial male precocious puberty) underscore the marked comparative differences that exist between rats and man in the responsiveness of their LC's to proliferative stimuli; and (4) several human epidemiology studies are available on a number of compounds that induce LCTs in rats (1,3-butadiene, cadmium, ethanol, lactose, lead, nicotine) that demonstrate no association between human exposure to these compounds and induction of LC hyperplasia or adenomas. (ABSTRACT TRUNCATED)

Kenny-Caffey syndrome and microorchidism

We report on two adolescent boys with Kenny-Caffey syndrome and microorchidism. The first patient had elevated levels of serum follicle-stimulating hormone, but normal levels of luteinizing hormone and testosterone. There was no evidence of a microdeletion of the Y chromosome. The second patient had Leydig cell hyperplasia with normal seminiferous tubules and spermatogenesis, and normal pituitary histologic findings at autopsy. The presence of microorchidism in these patients confirms the previous observations and suggests subfertility, but does not fully clarify the pathogenesis.

Male gonadal function in coeliac disease: III. Pituitary regulation

Pituitary regulation of gonadal function was investigated in 39 consecutive men with treated and untreated coeliac disease and in an intestinal disease control group of 19 men with Crohn's disease of similar age and general nutritional status. Basal serum FSH concentration was increased in 10 of the coeliacs (26%) compared to only two of 19 men with Crohn's disease (11%). This abnormality was observed with equal frequency in both treated and untreated coeliacs, and was not associated with oligospermia. Serum LH concentration was increased in eight of 15 untreated coeliacs (53%) with sub-total villous atrophy, an abnormality which unlike the elevation of serum FSH, appears to return towards normal after gluten withdrawal. Serum LH was high in coeliacs despite marked elevation of the free testosterone index. Exaggerated responses of FSH and LH to LHRH were found in 89% and 45% respectively, of coeliacs with sub-total villous atrophy. However, exaggerated responses of LH alone were found more frequently in coeliacs than in men with Crohn's disease (P less than 0.02) and unlike the exaggerated FSH responses, LH responses were closely related to jejunal morphology. Exaggerated responses of FSH and LH in coeliacs were commonly found when basal gonadotrophin concentrations were normal. The occurrence of exaggerated gonadotrophin responses could not be related to plasma concentration of testosterone, dihydrotestosterone, oestradiol or the free testosterone index. Serum prolactin was modestly raised in 25% of untreated and partially treated coeliacs and in the same proportion of men with Crohn's disease. Elevated serum prolactin concentrations never exceeded 809 mU/l and were not associated with impotence or infertility. This study provides further evidence that in men with coeliac disease there is a derangement of pituitary regulation of gonadal function. This would seem to be part of a wider disturbance of central regulatory mechanisms of endocrine function in coeliac disease.

Endocrine profile of 45 patients with Sertoli cell only syndrome

The basal serum levels of FSH, LH, prolactin and testosterone were determined in 45 patients with Sertoli cell only syndrome and were compared with the same in patients with Klinefelter's syndrome, oligozoospermic men and normal, fertile men. The serum FSH and LH levels in patients with Sertoli cell only syndrome were significantly higher than in normal males. The elevation of gonadotropins in patients with this syndrome was not so high, and the testosterone not lowered, as those in patients with Klinefelter's syndrome. The finding that the basal serum LH levels were elevated and serum testosterone levels were in normal range, demonstrated that there was compensated dysfunction of the Leydig cells in patients with Sertoli cell only syndrome.

Hyperplasia and the immature appearance of Sertoli cells in primary testicular disorders

Testicular biopsy specimens from adult patients affected with cryptorchidism, Klinefelter's syndrome, and Del Castillo's syndrome were examined by light and electron microscopy. The study revealed a high proportion of testes showing seminiferous tubules with hyperplasia of Sertoli cells (from 25 to 45 cells per transverse tubular section). These cells had an immature appearance and showed a pseudostratified distribution. The nucleus was round to ovoid and regular in outline, with a smaller nucleolus than that of mature Sertoli cells. The cytoplasm showed less development of the endoplasmic reticulum as well as of the secondary lysosomes and lipid droplets than that in mature Sertoli cells. Characteristic features of these immature Sertoli cells were abundant cytoplasmic microfilaments, elaborate interdigitations between adjacent cells, and extensive tight junctions, from basement membrane to lumen. In the cryptorchid testes, a more immature Sertoli cell was found to constitute the majority of the cells in hypoplastic zones. In Klinefelter's and Del Castillo's syndromes as well as in cryptorchid testes to a lesser degree, a transitional type of cell-from immature to mature-was also observed. These observations suggest that Sertoli cells in these primary testicular disorders reflect a congenital deficiency producing abnormal development.

Endocrine assessment of the subfertile male

Sixty-three male (XY) patients attending a subfertility clinic with average sperm density under 40 million/ml were studied by testicular biopsy and multiple basal estimations of plasma LH, FSH, testosterone as well as LHRH (50 micrograms i.v.) stimulation. A further forty patients with similar sperm densities also had testicular biopsy but only single estimations of the three hormones. A single basal FSH was found to be the best discriminator of testicular histologies. Patients with testicular biopsies showing germ cell aplasia in some or all seminiferous tubules (grades 3 and 4) had significantly higher basal FSH than those with hypospermatogenesis, germ cell arrest or normal appearance (grades 1 and 2). Basal FSH also showed a linear trend rising with decreasing sperm density but only rose above the normal range when sperm densities fell below 1 million/ml. When basal FSH, testicular histology and sperm density were considered together in the whole group (n = 100), high levels of FSH accurately indicated the presence of germ cell aplasia in some or all seminiferous tubules in azoo- and oligospermic men with sperm density under 5 million/ml. Normal FSH and azoospermia is diagnostic of obstruction in the excurrent ducts, and further investigation is undertaken if surgical correction of the obstruction is contemplated. Hormone estimations are not helpful in oligospermic patients with average sperm density over 5 million/ml. On the basis of these findings it is suggested that there is little place for the LHRH test in the routine assessment of male subfertility. Testicular biopsy is indicated only in oligospermic patients with average sperm density under 5 million/ml and normal basal FSH.

Exaggerated prolactin response to thyrotropin-releasing hormone and metoclopramide in primary testicular failure

Twenty-eight severely oligospermic and azoospermic men aged 20 to 42 years were challenged with luteinizing hormone (LH)-releasing hormone (LHRH), thyrotrophin-releasing hormone (TRH), and the dopaminergic antagonist, metoclopramide, given at 30-minute intervals. According to basal gonadotropin levels, the patients were subdivided into three groups: those with severe testicular failure (basal LH > 20 mIU/ml and FSH > 14 mIU/ml); those with moderate testicular failure with predominant seminiferous tubule involvement (LH < 20 mIU/ml and FSH > 14 mIU/ml) and those with mild testicular failure (LH < 20 mIU/ml and FSH < 14 mIU/ml. With one exception, mean basal prolactin (PRL) levels were normal in all patients. In all three groups, however, there was an exaggerated PRL response to TRH, the response in severe and moderate testicular failure being greater than that in mild testicular failure. The response to metoclopramide was increased only in the first two groups, not in the group with mild testicular failure. When individual patients and control subjects were considered together, the peak PRL response to TRH correlated with both basal and peak gonadotropin responses to LHRH. However, the PRL responses did not correlate with 17 beta-estradiol, estrone, testosterone, or the estradiol-testosterone ratio. It is concluded that oligospermic and azoospermic subjects with the most severe testicular failure and the highest gonadotropin levels have the greatest PRL increases after TRH and metoclopramide, indicating that the PRL response is related to the degree of testicular failure.

Endocrine studies of azoospermia. I. Serum steroid levels in Sertoli cell only syndrome

Estrone, estradiol, estriol, progesterone, 17 alpha-hydroxyprogesterone, testosterone, and dihydrotestosterone levels were determined in sera of 20 fertile men and 15 male patients with Sertoli cell only syndrome. In men with Sertoli cel only syndrome there was a significant decrease in serum estrone, estradiol, progesterone, 17 alpha-hydroxyprogesterone, and dihydrotestosterone and a significant increase in serum estriol and testosterone. Changes in endocrine profile discussed in relation to the possible role of inhibin.