Bilateral Cryptorchid Boys Research Articles

The positive predictive value of using fsh and Inhibin-B serum levels to diagnose gonadotropin insufficiency in bilateral cryptorchid boys is high

Despite early surgery, many boys with bilateral cryptorchidism at surgery have a reduced number of germ cells per tubular cross-section (G/T) in testicular biopsies and/or low inhibin-B with no elevated follicle-stimulating hormone (FSH) as expected based on a normal gonadotropin feed-back mechanism. Such boys have a high risk of later infertility because of insufficient gonadotropin stimulation and may benefit from adjuvant hormonal treatment. Testicular biopsies are not always wanted or accepted. The study aim was to investigate the value of a low inhibin-B and normal FSH to identify patients that might benefit from adjuvant hormonal treatment avoiding the need for testicular biopsy. A series of boys with cryptorchidism were evaluated with serum levels of inhibin-B and FSH in relation to G/T in testicular biopsies, which were compared to previously published age-matched normal control values. A total of 365 boys who underwent bilateral orchidopexy between 0.4 and 7.8 (median: 2) years of age were included. Twenty-seven (7%) patients had increased FSH and low G/T, whereas 11 of these also had low inhibin-B indicating hypergonadotropic hypogonadism. Moreover, 85 (23%) patients between 0.75 and 7.5 (median: 2) years of age had both low G/T (median: 0.3) and low inhibin-B (median: 56pg/ml) but normal FSH (median: 0.6 U/l) indicating a gonadotropin insufficiency. Three patients with normal FSH and low inhibin B had normal G/T. Our study shows that if surgeons prefer to avoid testicular biopsies and only wish to rely on hormonal parameters (low inhibin-B and normal FSH) in order to diagnose a gonadotropin insufficiency as the cause of hypogonadism, they will identify only about 30% of such cases and overlook about 70% of patients sharing the same endocrinopathy. In addition, if surgeons treat patients for gonadotropin insufficiency only based on low inhibin-B and normal FSH they will solely treat patients with gonadotropin insufficiency and would not overtreat patients. Adjuvant hormonal treatment was indicated by a gonadotropin insufficiency discerned in 23% of boys with bilateral cryptorchidism. Without histology, the clinicians are left with more difficult clinical judgments to identify patients for adjuvant hormonal treatment. The positive predictive value of low inhibin-B and normal FSH corroborated by low G/T was 0.97 (85/85+3), but the sensitivity was low (0.30).

Low Serum Inhibin B/Follicle-Stimulating Hormones and Anti-Müllerian Hormone/Follicle-Stimulating Hormones Ratios as Markers of Decreased Germ Cells in Infants with Bilateral Cryptorchidism

In cryptorchidism, germ cell development failure presents from infancy and may be reflected by altered hormonal levels produced by Sertoli cells. Our object was to assess for associations between serum hormone levels and testicular histopathology in cryptorchidism with an infertility risk according to the pretreatment undescended testicular positions. Prepubertal cryptorchid boys aged 7-91 (median 20) months who underwent orchidopexy between 2014 and 2019 were included (122 unilateral [median 19 months {range 7-91}], 23 bilateral [24 months {11-81}]). We evaluated the pretreatment testicular position and size; serum hormone levels; and the mean number of germ cells per tubule transverse section (G/T). We also performed a subgroup analysis of boys aged ≤24 months at orchidopexy. Serum inhibin B levels and G/T were significantly lower in bilateral than in unilateral cryptorchid boys (median 96 [range 46-197] pg/ml vs 125 [21-354] pg/ml, p=0.026; 0.20 [0-2.59] vs 0.65 [0-4.55], p <0.001, respectively). Inhibin B/follicle-stimulating hormones (FSH) and anti-Müllerian hormone (AMH)/FSH ratios were positively correlated with G/T in bilateral cryptorchid boys aged ≤24 months (12, p=0.008 and p=0.019, respectively). Low inhibin B/FSH and AMH/FSH ratios and high FSH were predictors of impaired G/T as per receiver operating characteristic curves (p=0.019, p=0.004 and p=0.004, respectively), whereas in unilateral cryptorchid boys aged ≤24 months, serum hormone levels and G/T did not differ with the pretreatment testicular positions. In bilateral cryptorchid boys aged ≤24 months at orchidopexy, low inhibin B/FSH and AMH/FSH ratios may reflect impaired G/T and future infertility risk.

MP55-04 LOW SERUM INHIBIN B/FOLLICLE-STIMULATING HORMONE AND ANTI-MULLERIAN HORMONE/FOLLICLE-STIMULATING HORMONE RATIOS AS MARKERS OF DECREASED GERM CELLS IN INFANTS WITH BILATERAL CRYPTORCHIDISM

You have accessJournal of UrologyPediatric Urology V (MP55)1 Sep 2021MP55-04 LOW SERUM INHIBIN B/FOLLICLE-STIMULATING HORMONE AND ANTI-MULLERIAN HORMONE/FOLLICLE-STIMULATING HORMONE RATIOS AS MARKERS OF DECREASED GERM CELLS IN INFANTS WITH BILATERAL CRYPTORCHIDISM Taiki Kato, Kentaro Mizuno, Hidenori Nishio, Akihiro Nakane, Satoshi Kurokawa, Hideyuki Kamisawa, Tetsuji Maruyama, Shoichiro Iwatsuki, Yukihiro Umemoto, Takahiro Yasui, and Yutaro Hayashi Taiki KatoTaiki Kato More articles by this author , Kentaro MizunoKentaro Mizuno More articles by this author , Hidenori NishioHidenori Nishio More articles by this author , Akihiro NakaneAkihiro Nakane More articles by this author , Satoshi KurokawaSatoshi Kurokawa More articles by this author , Hideyuki KamisawaHideyuki Kamisawa More articles by this author , Tetsuji MaruyamaTetsuji Maruyama More articles by this author , Shoichiro IwatsukiShoichiro Iwatsuki More articles by this author , Yukihiro UmemotoYukihiro Umemoto More articles by this author , Takahiro YasuiTakahiro Yasui More articles by this author , and Yutaro HayashiYutaro Hayashi More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002085.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: In cryptorchid boys, germ cell development failure occurs during infancy. Thus, the establishment of serum markers for predicting infertility is warranted. Serum inhibin B may reflect the state of the germinative epithelium. In this retrospective single-center observational study, we assessed the correlations between testicular histopathology and serum hormone levels according to testicular position in cryptorchid boys. METHODS: A total of 145 prepubertal boys underwent orchidopexy between December 2014 and May 2019 at our university hospital. Of them, 122 had unilateral cryptorchidism and 23 had bilateral cryptorchidism. Testicular biopsy was performed at orchidopexy. We examined the serum levels of inhibin B, anti-Mullerian hormone (AMH), gonadotropins, and testosterone; histological parameters; and the mean number of germ cells per seminiferous tubule cross-section (G/T). The area under the receiver operating characteristic (ROC) curve (AUC) showed the efficiency of each marker in predicting impaired germ cell numbers (below the lower limit of 0.4 G/T for boys without cryptorchidism). RESULTS: The mean G/T and serum inhibin B levels were significantly lower in the bilateral than in the unilateral cryptorchidism group (0.20 vs. 0.65, p<0.001; 96 [range 46–197] vs. 125 [range 21–354] pg/mL, p=0.026) (Table 1). Seven testes (4.1%) showed no germ cells (five boys with unilateral cryptorchidism and two boys with bilateral cryptorchidism). Inhibin B/follicle-stimulating hormone (FSH) and AMH/FSH ratios were correlated with the mean G/T in bilateral cryptorchid boys who were ≤24 months old at orchidopexy (n=12; p=0.008 and p=0.019, respectively). ROC curves showed significant correlations between impaired G/T and inhibin B/FSH (p=0.019, AUC 0.847) and AMH/FSH (p=0.004, AUC 0.932) ratios. CONCLUSIONS: In bilateral cryptorchid boys with a maximal age of 24 months, low inhibin B/FSH and AMH/FSH ratios may predict high risks for later infertility. Additional treatment and follow-up may be needed for such cases. Source of Funding: None © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e959-e959 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Taiki Kato More articles by this author Kentaro Mizuno More articles by this author Hidenori Nishio More articles by this author Akihiro Nakane More articles by this author Satoshi Kurokawa More articles by this author Hideyuki Kamisawa More articles by this author Tetsuji Maruyama More articles by this author Shoichiro Iwatsuki More articles by this author Yukihiro Umemoto More articles by this author Takahiro Yasui More articles by this author Yutaro Hayashi More articles by this author Expand All Advertisement Loading ...

The impact of early and successful orchidopexy on hormonal follow-up for 208 boys with bilateral non-syndromic cryptorchidism.

Inhibin-B is produced by Sertoli cells and decreased values might be associated with impaired fertility potential. The aim of the study was to evaluate the impact of bilateral orchidopexy on serum inhibin-B and follicle-stimulating hormone (FSH). A cohort study including 208 bilateral cryptorchid boys (median age: 1.7year) was evaluated with serum inhibin-B and FSH in relation to histological parameters. Based on the fertility potential, the boys were divided into three subgroups. At follow-up (median age: 2.7years) the boys were evaluated with FSH and in case of inhibin-B using multiple of the median (MoM). Inhibin-B MoM improved significantly at follow-up. In 32 boys with high FSH at orchidopexy 63% normalized FSH and 59% increased MoM inhibin-B, but 31% had impaired inhibin-B at follow-up. In 105 boys with transient hypogonadotropic hypogonadism, 52% increased inhibin-B MoM but 31% had impaired inhibin-B at follow-up. In 71 boys with normal FSH, inhibin-B, and G/T, 54% increased inhibin-B MoM and 15% had impaired inhibin-B at follow-up. The effect of the surgery was best in patients younger than 1year. Orchidopexy, especially before 1year of age, improves the fertility potential in bilateral cryptorchidism. At follow-up, 26% (54/208) had a risk of infertility based on inhibin-B.

Altered secretion of Sertoli cells hormones in 2-year-old prepubertal cryptorchid boys: a cross-sectional study.

In cryptorchid boys, failures in germ cell development have been clearly established. Some studies reported some abnormalities in Sertoli cells morphology but the results regarding their endocrine secretion remain controversial. To compare testicular hormone levels in young boys with and without cryptorchidism, we performed a cross-sectional hospital-based study. From surgery appointment records, we identified a case group of boys with unilateral or bilateral cryptorchidism and a control group undergoing dental care, minor osteoarticular or dermal surgery. Blood samples were withdrawn during the surgical procedure to perform testosterone, inhibin B and anti-müllerian hormone (AMH) immunoassays. We included 27 cryptorchid boys and 27 controls aged of 26.6 vs. 24.2months, respectively (p=0.172) far from the post-natal mini-puberty and the corresponding hormonal surges. Age-adjusted AMH and inhibin B levels were significantly lower in cryptorchid than in control boys (AMH: 87ng/mL vs. 135ng/mL; p=0.009, inhibin B: 97pg/mL vs. 133pg/mL; p=0.019, respectively). Moreover, AMH and inhibin B levels were significantly lower in the bilateral cryptorchid subgroup, being 50% lower than in the controls (p=0.011 and 0.019, respectively) and while both hormones levels were independent in controls, they became strongly correlated in bilateral cryptorchid boys (R²=0.75, p=0.001). In addition, testosterone levels were still detectable in some boys, with significantly lower levels in cryptorchid group than in controls. Overall, 2-year-old cryptorchid patients presented a simultaneous and significant drop in AMH and inhibin B levels, suggesting a functional defect of Sertoli cells. This deficiency appeared more pronounced in bilateral cryptorchidism and thus, regarding the pivotal role of Sertoli cells in germ cell development, it may explain the compromised fertility found later in men born with such a malformation.

Hormonal Aspects of the Pathogenesis and Treatment of Cryptorchidism.

A normal functioning hypothalamic-pituitary-testicular axis is required for normal testicular descent. The percentage of cases that result from a disturbance in this axis remains controversial. Much has yet to be learnt about cryptorchidism, but is seems that the existence of A dark spermatogonia (Ad spermatogonia) is essential for later fertility. Bilateral cryptorchid patients have a high risk of later infertility, even though they undergo early surgery for cryptorchidism. It is possible today to distinguish-to a certain extent-between three different groups of cryptorchid patients based on testicular histology, gonadotropins, and inhibin B at the time of early surgery: Group 1, patients suspected of prepubertal transient hypothalamic-pituitary-testicular hypofunction and a high risk of later infertility; Group 2, patients with hypergonadotropic hypogonadism and a primary testicular dysfunction; and Group 3, patients with normal histology and normal serum levels of inhibin B and gonadotropins at the time of early surgery and a low risk of later infertility. Given the potential adverse effects of hormonal treatment, attention should be directed toward small doses of adjuvant gonadotropin-releasing hormone (GnRH) treatment for those who might benefit the most, that is, bilateral cryptorchid boys at early surgery without evidence of normal maturation of gonocytes into Ad spermatogonia. Optimally, gonadotropin levels in such patients should be measured to ensure that levels are not compensatory elevated, thereby supporting the suspicion of hypothalamic-pituitary-testicular hypofunction. Studies of GnRH-supplementary treatment should include testicular biopsy at surgery and at follow-up in childhood as well as examinations of fertility potential in adulthood.

Bilateral vanished testes diagnosed with a single blood sample showing very high gonadotropins (follicle-stimulating hormone and luteinizing hormone) and very low inhibin B

In boys with cryptorchidism median serum values of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are higher and median serum values of inhibin B lower than in normal controls. Serum values of inhibin B reflect the state of germinative epithelium in cryptorchid testes. The aim of the study was to evaluate whether a simple blood sample of gonadotropins and inhibin B could diagnose bilateral vanished testes. Group I included five boys (4 months to 6 years and 3 months old) with bilateral vanished testes at laparoscopy. Group II included 82 boys with bilateral cryptorchidism younger than 7 years of age at surgery for bilateral cryptorchidism (median age 1 year and 9 months). The serum levels of hormones for the patients with vanished testes were: inhibin B 5?18 pg/ml, FSH 41-191 IU/l and LH 3.9?56 IU/l. The patients all had karyotype 46,xy. The serum levels of hormones from group II were: inhibin B median 122 (range 20?404) pg/ml, FSH median 0.8 (range 0.2?3.5) IU/l and LH median 0.2 (range 0.1-3.2) IU/l. The serum levels of inhibin B, FSH and LH from the boys with vanished testes were significantly different from the serum levels of the boys with bilateral cryptorchidism (p = 0.0026, p < 0.0001 and p < 0.0001, respectively). The serum values of gonadotropins and inhibin B from boys with bilateral vanished testes were significantly different from those of bilateral cryptorchid boys, indicating no germinative epithelium, no Sertoli cells and compensatory high gonadotropins. If such abnormal serum values are obtained from boys with bilateral non-palpable testes, tubular tissue is not present and surgery can be avoided.

Mutations in INSL3 and RXFP2 Genes in Cryptorchid Boys

Mutations in the INSL3 and RXFP2 genes have been associated with human cryptorchidism but with contrasting data. We analyzed the frequency of mutations in these genes in 600 newborns with cryptorchidism (396 unilateral and 204 bilateral) and 300 noncryptorchid subjects. We found five RXFP2 mutations in five bilateral cryptorchid boys, one INSL3 mutation in a unilateral cryptorchid boy, and one INSL3 mutation in a boy with unilateral cryptorchidism at birth and spontaneous descent during the first month of life. Overall, the frequency of INSL3 and RXFP2 mutations was therefore 7/600 at birth (1.2%) and 7/303 (2.3%) in persistent cryptorchid boys, with a higher prevalence of bilateral forms (5/120, 4.2%). No mutations were found in controls. This study confirmed the association between INSL3 and RXFP2 gene mutations and human cryptorchidism.

The relation of germ cells per tubule in testes, serum inhibin B and FSH in cryptorchid boys

At bilateral orchiopexy bilateral biopsies may be indicated to determine fertility potential. It is currently unknown if the serum inhibin B levels at time of orchiopexy reflect the testicular status of the bilaterally cryptorchid child. The aim of this study was to relate the results of inhibin B and FSH measurements with testicular biopsy parameters in bilateral cryptorchid boys. Included were 25 boys with bilateral cryptorchidism, median 2.5 years (9 months to 5.5 years) at surgery for bilateral cryptorchidism with simultaneous testicular biopsies, and blood sample for inhibin B and FSH. The number of spermatogonia and gonocytes was measured in 100 tubular transverse sections, the S/T and the mean-S/T of the patient was found, and expressed as percent of lowest normal value. Inhibin B and FSH were measured and related to age-specific values. Forty percent (10/25) of the patients had very low mean-S/T (mean-S/T<10% of lowest normal-value). Inhibin B was decreased in 24% (6/25) of the patients, all with decreased mean-S/T, predominantly with a mean-S/T<10% of lowest normal-value (p<0.05). There was a negative correlation between inhibin B and FSH (p<0.05). In cases of mean-S/T<10% of lowest normal-value and decreased inhibin B, we found increased FSH in 9% (2/22) of the patients and hypergonadotropic hypogonadism was suspected. Low FSH was found in 5% (1/22) of the patients and hypogonadotropic hypogonadism was suspected. Low inhibin B predicts a serious condition in respect of infertility. Low FSH and inhibin B indicates examination for hypogonadotropic hypogonadism. In bilateral cryptorchid boys inhibin B levels correlated negatively to FSH.

Infertility despite surgery for cryptorchidism in childhood can be classified by patients with normal or elevated follicle-stimulating hormone and identified at orchidopexy.

To analyse infertility despite orchidopexy in childhood. The study comprised patients with cryptorchidism (70 bilateral and 65 unilateral) who had a simultaneous biopsy taken at orchidopexy in childhood, and in adulthood had analyses of semen and FSH. In adulthood 42 formerly bilateral cryptorchid boys had repeat testicular biopsies taken. Infertility was suspected in men with < 5 million sperm/mL in the best sample of semen and concomitant poor sperm motility, and who were classified by follicle-stimulating hormone (FSH) values. At orchidopexy the number of spermatogonia/tubule and the germ cell differentiation were measured. In adulthood the percentage of tubules with complete spermatogenesis, spermatogenic arrest and Sertoli-cell only status was assessed. Infertility was suspected in 38 of 70 (54%) of formerly bilateral and six of 65 (9%) formerly unilateral cryptorchid patients. High FSH values were expected in these suspected infertile patients, but 15 of 38 (59%) formerly bilateral and five of six formerly unilateral cryptorchid patients had normal FSH values. These patients were identified in childhood at orchidopexy; those with bilateral cryptorchidism generally presented with germ cells, but the mean number of spermatogonia per tubule was < 30% of the lowest normal value, and the germ cells were seldom normally differentiated, whereas those with unilateral cryptorchidism generally lacked germ cells in the biopsies. No patients had a decreased FSH value. Despite surgery for cryptorchidism, infertility was probable in a third (44 of 135) of the patients. We expected high FSH values in these patients, but in 45% (20/44) the FSH values were normal. These patients may have relative FSH deficiency. At orchidopexy these patients were identified to be bilaterally cryptorchid with few germ cells and those unilaterally cryptorchid had none in the biopsy. After orchidopexy in childhood, additional hormonal treatment, e.g. recombinant FSH or buserelin, may be indicated in these patients.

Treatment of cryptorchidism with low doses of buserelin over a 6-months period.

In a collaborative study, 48 prepubertal boys with undescended testes ranging in age from 15 months to 11 years were treated with low-dose intranasal buserelin following an every-other-day programme for a period of 6 months. Urinary LH, FSH, and testosterone were not altered during the treatment period. Boys over 7 years of age experienced a slight but significant rise in testosterone at the end of treatment. Testicular descent was achieved in only 17% of boys. In the remainder, bilateral testicular biopsies were obtained during orchiopexy. Grouped analysis showed a significant increase in the number of germ cells per tubule in both unilateral and bilateral cryptorchid boys, suggesting that buserelin treatment of the testis in a cryptorchid position is capable of improving fertility potential. If time-matched controls are compared to treated boys of the same age, again a significant difference is observed indicating that buserelin treatment does increase the germ cell count.

Pituitary and gonadal function in prepubertal and pubertal cryptorchidism.

LRH and hCG tests were performed in 35 prepubertal and 35 pubertal boys with unilateral or bilateral cryptorchidism to examine the pituitary and gonadal function. Twenty-one normal boys were also examined as controls. In the prepubertal group, distinct increases in serum LH, FSH and testosterone levels by LRH and hCG tests were found in all of the normal and unilateral cryptorchid boys. However, no or very little response was observed in 4 out of 17 boys with bilateral cryptorchidism. In the pubertal group, serum levels of LH, FSH and testosterone in normal boys, in unilateral and in bilateral cryptorchid boys were evidently higher than those in the prepubertal group, and distinct or moderate responses by the LRH and hCG tests were found in all boys examined. Although serum testosterone levels were similar in all groups, serum basal and peak gonadotrophin levels by the LRH test were significantly higher in bilateral cryptorchid boys than in normal and unilateral cryptorchid boys. The difference was more marked in FSH than in LH level. An elevated level of serum LH is suggestive of the hypofunction of not only the seminiferous tubules but also of the Leydig cells in cryptorchid testes.

Further support for a gonadotrophine deficiency in cryptorchidism derived from clinical investigations

In 73 uni- and bilateral cryptorchid boys (2-13 years of age) LH and FSH response to LH-RH (or long acting LH-RH derivative HOE 766) was assessed. In all patients a testicular biopsy -taken during orchidopexy- was examined by light and electronmicroscopy. Plasma LH increased from 3, 5 to 10, 1 mU/ml and FSH from 1, 5 to 4, 5 mU/ml in response to 100 ug LH-RH, testosterone (mean 0, 48 ng/ml) and E2 (mean < 30 pg/ml) did not increase significantly. In 34/73 patients the LH concentration rose to < 4 mU/ml above the basal value, in 11 plasma LH was not stimulated at all. A pronounced stimulation of FSH of > 4 mU above basal concentration was seen in 30/73 boys. In all biopsies of patients with no LH response, Leydig cells were spare in the interstitium. Collagenization of interstitium and of peritubular connective tissue could not be related to LH and FSH. Unequivocally the number of spermatogonia was reduced and their ultrastructural appearance pathological.

FSH: III. Evidence for a possible prepubertal regulation of its secretion by the seminiferous tubules in cryptorchid boys.

Two groups of prepubertal unilateral cryptorchid boys, 42▵12 to 12 years of age, underwent stimulation tests with 1 μg (n = 10) or 25 μg (n = = 8) of LHRH. Two groups of prepubertal bilateral cryptorchid boys, 52▵12 to H9▵12 years of age, were similarly studied (1 μg, n = 6; 25 μg, n = 8). For comparison, control groups of both prepubertal boys, 66▵12 to 119▵12 Via years of age (1 μg, n = 9; 25 μg, n = 11), and pubertal boys, 12 5/12 to 14 years of age (1 μg, n = 11), were also tested for response to LHRH. All patients had surgical descents of the cryptorchid testes with bilateral biopsy of the testes at that time. The number of spermatogonia per 50 transverse tubular sections was determined. Unilateral cryptorchid groups exhibited FSH responses to 1 and 25 μg of LHRH similar to those of the prepubertal control groups. The numbers of spermatogonia were low (means ± SE of 12 ± 6 to 25 ± 12) on the cryptorchid side, and in the normal range (greater than 50 per 50 tubular transverse sections) on the normal s...

FSH: Evidence for a possible prepubertal regulation of its secretion by the germinal epithelium in cryptorchid boys

Two groups of prepubertal unilateral cryptorchid boys (UCT) underwent stimulation tests with 1 μg (n=10) or 25 μg (n=8) of LHRH. Two groups of prepubertal bilateral cryptorchid boys (BCT) were similary studied (1 μg, n=6; 25 μg, n=8). The number of spermatogonia was determined in both sides in each group after testicular biopsy. UCT groups exhibited FSH and LH responses to LHRH similar to those of prepubertal control groups. Mean numbers of spermatogonia were low on the cryptorchid side (12 ± 6 to 25 ± 12) and normal on the normal side (>50). Both groups of BCT had very low counts of spermatogonia on both sides (means of 7 ± 4 to 14 ± 8). Their FSH responses to LHRH at both dosages were significantly higher than those of the normal prepubertal controls. LH responses were identical. These data suggest that the negative feedback mechanism between FSH secretion and the spermatogonia observed in the adult male is also operative in the prepubertal boy.

Letter: Serum gonadotropins in cryptorchidism.

Sir .—I read with great interest the article by Lee et al in the April issue of theJournal(127:530, 1974). Looking back 37 years, Hess et al studied the urinary excretion of gonadotropic hormone (pregnancy urine extract) in unilateral and bilateral cryptorchid boys. 1,2 They found that in some instances of bilateral cryptorchidism, there was an increased excretion of gonadotropic hormone, which indicated to us that there was either anorchidism or compromised testicular function in the presence of a physiologically active pituitary gland. As I no longer have access to the original articles nor reprints, I am unable to supply further details of the study. However, if Dr. Lee and his co-workers are interested, they may wish to read the articles.