Serum concentrations of dihydrotestosterone are associated with symptoms of hypogonadism in biochemically eugonadal men.

PURPOSE: Symptoms of hypogonadism are often reported by subjects with normal serum testosterone (T) levels. We aimed to assess the association between clinical symptoms in andrological outpatients and sex steroids levels. METHODS: This is a retrospective cross-sectional cohort study in an Academic clinic and research unit. International Index of Erectile Function (IIEF, EF domain) and Aging Males Symptoms scale (AMS) questionnaires were completed by 635 and 574 men, respectively (mean age: 47.3 ± 13.9 and 47.4 ± 13.8 years, p = 0.829), free of interfering medications with complaints possibly related to hypogonadism. RESULTS: Serum total/free T as well as dihydro-T (DHT) was associated with IIEF-EF and AMS scores in the overall population using univariate analyses. Multivariate approaches revealed DHT concentrations in subjects with normal T levels (n = 416, Total T > 12 nmol/L) to be significant predictors of AMS scores. A 0.1 nmol/l serum DHT increase within the eugonadal range was associated with a 4.67% decrease in odds of having worse symptoms (p = 0.011). In men with biochemical hypogonadism (Total T < 12 nmol/L), total and free T rather than DHT were associated with AMS results. This association was not found for IIEF-EF scores. Indirect effects of age and BMI were seen for relations with hormone concentrations but not questionnaire scores. CONCLUSION: DHT can be associated with symptoms of hypogonadism in biochemically eugonadal men. Serum DHT measurement might be helpful once the diagnosis of hypogonadism has been ruled out but should not be routinely included in the primary diagnostic process.

Monitoring testosterone replacement therapy with transdermal gel: when and how?

PURPOSE: Testosterone replacement therapy (TRT) is recommended for the treatment of most cases of male hypogonadism. Transdermal testosterone (T) gels are commonly used in clinical practice; however, there is little evidence concerning how to monitor dosage to bring and maintain serum T levels in the normal physiologic range. METHODS: We examined 30 hypogonadal patients undergoing treatment with 40 mg/day transdermal 2% testosterone gel. After a week from treatment onset, all patients underwent a total of four measurements to assess serum total T, bioavailable T and free T at + 2 h (samples A and A') and + 23 h (samples B and B'). RESULTS: No significant difference was found concerning total, free and bioavailable T between the two samples taken at the same time points (A vs A' and B vs B'). A repeated-measures mixed effects regression model showed significantly lower serum levels of total, free and bioavailable T at + 23 h compared to + 2 h (total T, ß = - 3.050 ± 0.704, p < 0.001; free T, ß = - 85.187 ± 22.746, p < 0.001; bioavailable T, ß = - 1.519 ± 0.497, p = 0.003) without a significant between-sample variability. Serum T > 3.5 ng/ml at + 2 h was reached in 21/30 patients (70%), but only 11 (36.7%) still had adequate serum T at + 23 h. CONCLUSION: Assessment of TRT with transdermal gels at its peak and at its minimum could be useful in providing a finely tailored treatment for hypogonadal men, both preventing supra-physiological levels and maintaining adequate concentrations through the day.

A diagnostic germ cell score for immature testicular tissue at risk of germ cell loss.

STUDY QUESTION: Can a systematic scoring procedure provide crucial information on the status of highly heterogeneous immature human testicular tissues in the context of cryopreservation for fertility preservation? SUMMARY ANSWER: We developed a systematic histological score as a novel diagnostic tool which differentiates the patient cohort according to the status of germ cell differentiation and number of spermatogonia (normal, diminished and absent), and which could be relevant in the fertility clinic. WHAT IS KNOWN ALREADY: Cryopreservation of testicular tissue of immature boys is currently considered the option for future fertility restoration. However, experimental techniques for the derivation of sperm as well as valid diagnostic scoring of these immature testis tissues are not yet reported. STUDY DESIGN, SIZE, DURATION: Testicular tissues of 39 patients (aged 2-20 years) who attended our clinic for cryopreservation between 2010 and 2015 were analyzed to determine the variability of testicular tissue composition, germ cell numbers and differentiation status. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human testicular tissue samples were divided into three groups. Group NT included patients suffering from diseases which do not directly affect the testes (n = 6; aged 6-14 years), group AT included patients suffering from diseases that directly affect the testes (n = 14; 2-17 years), and group KS (Klinefelter patients, n = 19; 12-20 years). Based on immunohistochemical stainings for MAGEA4, the differentiation status as well as the numbers of gonocytes, spermatogonia and spermatocytes were determined. MAIN RESULTS AND THE ROLE OF CHANCE: Testicular tissue samples from the NT group contained a mean of 100.3 spermatogonia/mm3 (×103). Highly heterogeneous and significantly lower mean numbers of spermatogonia were scored in testes from boys after cytotoxic exposures or with pre-existing disease (AT group: 35.7 spermatogonia/mm3 (×103); KS group: 1.8 spermatogonia/mm3 (×103)). In addition, the germ cell differentiation status was determined and revealed tissues with either spermatogonia and gonocytes, only spermatogonia, spermatogonia and spermatocytes, or all three germ cell types were present. Based on spermatogonial numbers and differentiation status, we developed a germ cell score which we applied to each individual patient sample. LIMITATIONS REASONS FOR CAUTION: Normal human testicular tissue samples are difficult to obtain for ethical reasons and the sample numbers were small. However, six such samples provide a valid baseline for the normal situation. WIDER IMPLICATIONS OF THE FINDINGS: Fertility preservation of immature male tissues is an emerging field and is currently offered in many specialized centers worldwide. Our diagnostic germ cell score delivers an easily applicable tool, facilitating patient counseling and thus ensuring comparability between the centers with regard to future studies. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Funding Initiative: Translational Research, Ministry of Innovation, Science and Research, Federal State of North Rhine Westphalia (z1403ts006). The authors declare that they do not have competing financial interests.

Testosterone supplementation and body composition: results from a meta-analysis of observational studies.

PURPOSE: The concept of testosterone (T) supplementation (TS) as a new anti-obesity medication in men with testosterone deficiency syndrome (TDS) is emerging. Data from placebo-controlled trials are more conflicting. The aim of this study is to systematically review and meta-analyze available observational and register studies reporting data on body composition in studies on TS in TDS. METHODS: An extensive MEDLINE, Embase, and Cochrane search was performed including the following words: "testosterone" and "body composition." All observational studies comparing the effect of TS on body weight and other body composition and metabolic endpoints were considered. RESULTS: Out of 824 retrieved articles, 32 were included in the study enrolling 4513 patients (mean age 51.7 ± 6.1 years). TS was associated with a time-dependent reduction in body weight and waist circumference (WC). The estimated weight loss and WC reduction at 24 months were -3.50 [-5.21; -1.80] kg and -6.23 [-7.94; -4.76] cm, respectively. TS was also associated with a significant reduction in fat and with an increase in lean mass as well as with a reduction in fasting glycemia and insulin resistance. In addition, an improvement of lipid profile (reduction in total cholesterol as well as of triglyceride levels and an improvement in HDL cholesterol levels) and in both systolic and diastolic blood pressure was observed. CONCLUSIONS: Present data support the view of a positive effect of TS on body composition and on glucose and lipid metabolism. In addition, a significant effect on body weight loss was observed, which should be confirmed by a specifically designed RCT.

Hormonal male contraception in men with normal and subnormal semen parameters.

Hormonal male contraception based on testosterone alone or on a combination of testosterone with a gestagen has been shown to suppress spermatogenesis effectively and to be fully reversible. However, clinical studies to date have only included volunteers with so-called 'normal' semen values by WHO standards. As a male contraceptive should be available to all interested men regardless of their semen parameters, we investigated how volunteers with subnormal semen parameters would respond to hormonal male contraception. During a 34-week treatment phase, the volunteers received injections of 1000 mg testosterone undecanoate in weeks 0, 6, 14 and 24. This was followed by a 24-week recovery and follow-up period. As it was not known whether men with subnormal semen parameters would recover to starting levels, cryopreservation of semen was offered to all subnormal volunteers. Twenty-three men with normal semen parameters and 18 with sperm counts below 20 million completed the trial. The normal volunteers showed the expected response with 17 suppressing sperm counts below 1 million/ejaculate (13 showing azoospermia) and six not-suppressing below 1 million sperm/ejaculate. By the end of the recovery period, all sperm counts had returned to the range of starting values. The subnormal group showed a similar pattern with 13 of 18 (= 72%) men suppressing below 1 million/ejaculate (8/18 = 44% showing azoospermia) and the remaining 5 of 18 (= 28%) not-suppressing sperm counts below 1 million/ejaculate. All sperm counts returned to the starting range. The study shows that in Caucasian men with normal sperm counts as well as in men with subnormal sperm counts, testosterone alone can produce azoospermia in about half and suppression below one million in about two-thirds of the volunteers. The same proportion of men in both groups appears to require an additional gestagen for full contraceptive protection. Most importantly, regarding suppressibility and reversibility, volunteers with normal and subnormal sperm counts display the same pattern.

Physical activity and memory functions: are neurotrophins and cerebral gray matter volume the missing link?

Epidemiological studies reveal better cognitive function in physically active individuals. Possible mediators for this effect are neurotrophins, which are up-regulated through physical exercise and induce neuronal growth and synaptogenesis in the animal model. Here we cross-sectionally assessed 75 healthy older individuals for levels of physical activity, aerobic fitness, and memory encoding, as well as neurotrophin levels and cerebral gray matter volume. We found that physical activity, but not cardiovascular fitness, was associated with better memory encoding after controlling for age, sex, education, depression, alcohol consumption, and smoking. Higher levels of physical activity were associated with higher levels of the neurotrophin granulocyte colony stimulating factor (G-CSF) and increased cerebral gray matter volume in prefrontal and cingulate cortex as assessed by magnetic resonance voxel-based morphometry. While mediating factors will need to be further elucidated, these findings indicate that even low-level physical activity exerts beneficial effects on memory functions in older individuals.

The role of the CAG repeat androgen receptor polymorphism in andrology.

A dysfunctional androgen receptor is able to cause variable phenotypes of androgen insensitivity or androgenicity in humans. In addition, also a polymorphism, the CAG repeat polymorphism in exon 1 of the androgen receptor gene (CAG)n, modulates androgen effects: androgen-induced target activities are attenuated corresponding to the length of triplet residues. Clinically, the (CAG)n polymorphism causes marked modulations of androgenicity in eugonadal men in various tissues and psychological traits and may cause the clinical picture of hypogonadism in the presence of normal testosterone concentrations. Also pharmacogenetic implications might exist in this regard: there appears to be a significant role of testosterone treatment of hypogonadal men as treatment effects have been demonstrated to be modulated by the number of (CAG)n in retrospective approaches.

The triad of erectile dysfunction, hypogonadism and the metabolic syndrome.

AIM: To identify the relationship of erectile dysfunction, hypogonadism and the metabolic syndrome in the context of men's health. METHODS: An Expert Panel Meeting was held in December 2006 in Vienna, Austria. In addition a comprehensive literature search was conducted. RESULTS: Men have a higher incidence of cardiovascular events than women of similar ages which has led to the belief that testosterone is a risk factor for cardiovascular disease in men. The latter hypothesis is no longer tenable. On the contrary, low testosterone levels are associated with (visceral) obesity, the metabolic syndrome, diabetes mellitus, cardiovascular disease and erectile dysfunction (ED). Testosterone therapy does not lead to an increased incidence of cardiovascular disease or events such as myocardial infarction, stroke or angina. Until recently (visceral) obesity, the metabolic syndrome, diabetes mellitus, cardiovascular disease and ED were viewed as more or less independent entities affecting the ageing male. It was not recognised that hypogonadism is a common denominator. With a more integrative approach to the health situation of middle-aged and elderly men, these conditions appear closely interrelated in their manifestations, hypothetically in their aetiology, diagnostic strategy and also their treatment. CONCLUSION: Improving sexual health is a portal to identify health hazards and improving men's health. Appropriate diagnosis and medical work up of men presenting with sexual symptoms may have the benefit of the diagnosing and treating other important conditions, such as obesity, diabetes, hypertension and hyperlipidaemia.

A history of undescended testes in young men with Klinefelter syndrome does not reduce the chances for successful microsurgical testicular sperm extraction.

Klinefelter syndrome (KS) and undescended testes (UDT) are known etiologies for non-obstructive azoospermia (NOA), and coexistence of both etiologies is not uncommon. Patients with both KS and a history of UDT are therefore considered to have extremely reduced chances for paternity. We aimed to analyze the impact of previous surgically corrected unilateral or bilateral UDT on sperm retrieval rates (SRRs) by microsurgical testicular sperm extraction (mTESE) in azoospermic men with KS. Age, testicular volumes, and hypothalamo-pituitary-gonadal axis function were investigated in relation to SRRs in 29 non-mosaic KS patients (47,XXY) with a history of UDT (group 1) who underwent mTESE between 2008 and 2016 in our center and compared to the data of age- and serum testosterone-matched non-mosaic KS controls with eutopic testes at birth (group 2), and to those of 51 men with NOA and a normal male karyotype (46,XY), but previous UDT (group 3). SRRs in KS patients with surgically corrected UDT during childhood were comparable to SRRs of KS patients with eutopic testes at birth: 31% (35% in unilateral and 22% in bilateral UDT) vs. 38% (p = 0.581). SRRs and Leydig cell function in group 1 were negatively correlated with age. Significantly higher SRRs (66%) were found in euploid azoospermic men with surgically corrected UDT (p < 0.001). A history of UDT does not preclude chances for future fatherhood in young azoospermic males with KS. In one of three men with previous unilateral UDT and in one of 4-5 in those with previous bilateral UDT, spermatozoa can be harvested by mTESE during late adolescence or young adulthood for immediate or future use in assisted reproduction.

Impact of various progestins with or without transdermal testosterone on gonadotropin levels for non-invasive hormonal male contraception: a randomized clinical trial.

Although several progestins have been tested for hormonal male contraception, the effects of dosage and nature of various progestins on gonadotropin suppression combined with and without additional testosterone has not been performed in a comparative trial. The aim of this study was to evaluate the differential impact of four oral or transdermal progestins on the suppression of gonadotropins in healthy men: oral: cyproterone acetate (CPA), levonorgestrel (LNG), norethisterone acetate (NETA), and transdermal: Nestorone® (NES), all in combination with transdermal testosterone (T). Randomized clinical trial testing was performed with four progestins at two doses each. After a 2-week progestin-only treatment, transdermal T was added for further 4 weeks and was followed by a 3-week recovery period. Progestin-dose per day: CPA 10 mg/20 mg, NES 2 mg/3 mg/dose e.g. 200/300 µg/day absorbed, NETA 5 mg/10 mg, LNG 120 µg/240 µg. From an andrology outpatient clinic, 56 healthy men aged 18-50 years, with body mass index ≤33 kg × m-2 were included in the study. Serum concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were studied. Secondary outcome measure included were serum testosterone concentrations, sperm concentrations, and safety parameters. Intergroup comparisons demonstrated that CPA and LNG had the strongest effect on LH/FSH suppression. Nevertheless, every substance showed significant inhibitory effects on gonadotropin secretion, especially in combination with transdermal T. A decrease in hematocrit and insulin sensitivity as well as cholesterol subfractions and triglycerides was uniformly seen for every group. The combination of oral or transdermal progestins with a transdermal testosterone preparation is able to suppress gonadotropins. Further dose titration studies with sperm suppression as an end-point should be conducted to determine the lowest effective dose for hormonal male contraception.

Testicular function during puberty and young adulthood in patients with Klinefelter's syndrome with and without spermatozoa in seminal fluid.

Patients with Klinefelter's syndrome experience progressive testicular degeneration resulting in impaired endocrine function and azoospermia. What proportion of adolescents develop testosterone deficiency during puberty and how many have spermatozoa in their semen is unclear to date. We aimed to investigate testicular function during puberty and young adulthood in patients with Klinefelter's syndrome and to assess testosterone effects in target tissues. The clinical data of 281 patients with non-mosaic Klinefelter's syndrome aged 10-25 years without previous testosterone replacement were reviewed. In late pubertal adolescents, semen analyses were evaluated, and testicular volumes, hormone and haemoglobin (Hb) levels, the number of CAG repeats and final height data were compared to those of 233 age-matched controls with pubertal gynaecomastia. Spontaneous pubertal virilisation to Tanner stages IV-V occurred. Serum T levels ≥10 nmol/L were reached in 62% of patients with Klinefelter's syndrome and in 85% of controls at ages 15-25 (TKFS : 12.2 ± 5.4 vs. TC : 16.6 ± 7.2 nmol/L). LHKFS levels were elevated >10 U/L in 84%, and normal in all controls (LHKFS : 18.6 ± 12.2 vs. LHC : 3.5 ± 1.6 U/L). In nine of 130 (7%) adolescents with Klinefelter's syndrome, spermatozoa (oligozoospermia) were found in semen; all had T levels >7 nmol/L and eight of nine had LH levels ≤18 U/L, while their hormone levels, number of CAG repeats and testicular volumes were not different from those of adolescents with azoospermia. Controls had normal sperm concentrations in 73% (46/63). Semen volumesKFS were normal in 55% vs. 78% in controls; HbKFS was normal in 89% (HbC : 97%). Mean final heightKFS was 185 ± 8 cm vs. 181 ± 7 cm in controls. Hypergonadotropic hypogonadism develops during early puberty in adolescents with Klinefelter's syndrome and remains compensated in over 60% during ages 15-25, with sufficient testosterone secretion for spontaneous accomplishment of pubertal development. Spermatozoa in semen are rare and associated with T levels >7 nmol/L. Parameters reflecting androgen deficiency in target tissues may help to optimise timing of testosterone substitution, which should preferably not be initiated before fertility status has been clarified.

Causes of hypogonadotropic hypogonadism predict response to gonadotropin substitution in adults.

Germ cell and Sertoli cell proliferation and maturation in human testes occur in three main waves, during the late fetal and early neonatal period and at early puberty. They are triggered by periods of increased activity of the hypothalamic-pituitary-gonadal (HPG) axis. In hypogonadotropic hypogonadism (HH), these processes are variably disturbed. The objective of this study was to explore whether success of gonadotropin replacement in HH men is predictable by the origin of HH, indicating time of onset and severity of GnRH/gonadotropin deficiency. The data of 51 adult HH patients who had undergone one cycle of hCG/FSH treatment were reviewed. Five groups were established, according to the underlying HH origin. Therapeutic success by final bi-testicular volumes (BTVs) final sperm concentrations (SC) and conception rates were compared and related to baseline parameters, indicative of the degree of HPG-axis disruption. Overall, BTVs rose from 13 ± 15 to 27 ± 15 mL, spermatogenesis was induced in 98%, with mean SCs of 15 ± 30 mill/mL, spontaneous pregnancies in 37% and additional 18% via intracytoplasmic sperm injection. Kallmann syndrome patients had the poorest responses (BTV: 16.9 ± 10 mL; SC: 3.5 ± 5.6 mill/mL), followed by patients with congenital/infancy-acquired multiple pituitary hormone deficiencies (MPHD) and patients with HH+absent puberty (BTV: 21 ± 14/24 ± 9 mL; SC: 5.5 ± 6.5/ 14.5 ± 23.8 mill/mL). HH men with pubertal arrest and with post-pubertally acquired MPHD had the best results (BTV: 36 ± 14/38 ± 16 mL; SC: 25.4 ± 34.2/29.9 ± 50.5 mill/mL). Earlier conception after 20.3 ± 11.5 months (vs. 43.1 ± 43.8; p = 0.047) of gonadotropin treatment with higher pregnancy rates (62% vs. 42%) was achieved in the two post-pubertally acquired HH subgroups, compared to the three pre-pubertally acquired. Therapeutic success was higher in patients without previously undescended testes, with higher baseline BTVs (pre- vs. post-pubertal HH: 5 ± 4 mL vs. 26 ± 16 mL; p < 0.0001) and higher baseline inhibinB levels (pre- vs. post-pubertal HH: 16.6 vs. 144.5 pg/mL; p = 0.0004). The cause of HH is a valuable predictor of outcome of gonadotropin replacement in adults.

[Erectile Dysfunction in Diabetic Men - Current Diagnostics and Therapy]. / Erektile Dysfunktion beim Diabetiker. Aktuelle Diagnostik und Therapie.

Sexual functional dysfunctions represent a multidimensional nosological entity. Apart from the directly measurable pathophysiological parameters, psychological and dynamic partnership aspects are almost always involved. These can exert a triggering and a potentiating influence. Similarly, sociocultural factors have to be taken into account. In men the problem most frequently has a physiological focus and the main symptom within the complex of sexual difficulties, especially for diabetic patients, is erectile dysfunction. Disorders of ejaculation and orgasm may also occur. Testosterone production in men may be impaired due to obesity-related dysfunctions of the hypothalamic-pituitary-gonadal axis and this can lead to a clinically significant androgen deficit and thus also to a decline of libido.

Inhibin B, AMH, but not INSL3, IGF1 or DHEAS support differentiation between constitutional delay of growth and puberty and hypogonadotropic hypogonadism.

In pre-pubertal boys ≥ 14 years, the differentiation between constitutional delay of growth and puberty (CDGP) and hypogonadotropic hypogonadism (HH) is challenging, as current diagnostic tools have limitations in sensitivity and specificity. The aim of this study was to assess the usefulness of markers of gonadal activity, growth axis activation and adrenarche in differentiation between pre-pubertal CDGP and HH. This retrospective study was carried out between 2006 and 2015 in an academic out-patient referral centre. The clinical data of 94 boys, aged 13.9-23.2 years and referred for "pubertal delay" were reviewed. Definite diagnoses were established on initial work-up and clinical follow-up: 24 boys were diagnosed with HH, 22 boys with CDGP, pre-pubertal (PP CDGP) at referral and 28 boys with CDGP, early pubertal at referral (EP CDGP), the latter serving as control group. Twenty patients were excluded from evaluation because of previous sex steroid treatment or associated chronic disease. Inhibin B and AMH were measured in all (n = 74); INSL3, IGF1, IGFBP3 and DHEAS in a subset of patients (n = 45) in serum of first presentation. Inhibin B and AMH were higher in boys with PP CDGP than in boys with HH: inhibin B: 87.6 ± 42.5 vs. 19.8 ± 13.9 pg/mL; p < 0.001; AMH: 44.9 ± 27.1 vs. 15.4 ± 8.3 ng/mL; p < 0.001. Receiver operating characteristics (ROC) for the diagnosis of PPCDGP vs. HH (inhibin B ≥ 28.5 pg/mL): sensitivity: 95%, specificity: 75%; AUC: 0.955. In combination with an AMH cut-off ≥20 ng/mL the specificity increased to 83%. INSL3, IGF1, IGFBP3 and DHEAS levels were not different. In boys with EP CDGP, inhibin B and IGF1 levels were highest (138.7 ± 59.9 pg/mL/289.7 ± 117 ng/mL), whereas AMH levels were lowest (11.7 ± 9.1 ng/mL). Sertoli cell markers are helpful for establishing a prognosis, whether a boy with pubertal delay will enter puberty spontaneously, whereas Leydig cell, growth and adrenal markers are not.

Treatment strategies for severe oligoasthenoteratozoospermia (OAT) (<0.1 million/mL) patients.

Intracytoplasmic sperm injection (ICSI) using spermatozoa from patients with severe oligoasthenoteratozoospermia is still a challenge. Although spermatozoa are available, lower fertilisation rates as well as compromised pregnancy rates are observed after ICSI. We aimed at identifying respective parameters in the pre-values of ejaculate samples used for couple counselling. The clinical pre-values of 121 patients and their corresponding 228 ICSI cycles performed between 2002 and 2010 were retrospectively analysed. Patients were divided into three groups: (i) group 1 (G1, n = 51) where all patients showed at least once <0.1 million/mL and ICSI was performed using ejaculate alone; (ii) group 2 (G2, n = 14) patients had once <0.1 Mill/mL or azoospermia and a testicular biopsy before start of ICSI; (iii) group 3 (G3, n = 56) patients were azoospermic and directed immediately to testicular sperm extraction (TESE). The pre-values of G2 differed significantly from G1 in terms of volume and motility. Lutenizing hormone (LH) and follicle-stimulating hormone (FSH) values were equal in G1 and G2, but showed significant differences in comparison to G3. Testis volume was significantly higher in G3. In the corresponding ICSI cycles, the percentage of cancelled embryo transfers was highest in G3. We did not find any correlations of hormonal markers or sperm pre-values with the success rates of ICSI. In our patient cohort, spermatozoa retrieved either from ejaculate or testicular biopsies have nearly identical chances in achieving pregnancies. Patients in need of TESE before ICSI have significantly lower sperm counts. However, it is not possible to calculate threshold values as indicator for TESE.

Age and markers of Leydig cell function, but not of Sertoli cell function predict the success of sperm retrieval in adolescents and adults with Klinefelter's syndrome.

Microsurgical testicular sperm extraction (mTESE), combined with intracytoplasmic sperm injection (ICSI) represents a chance for azoospermic men with Klinefelter's syndrome (KS) to father children. The objective of this study was to identify predictive factors for the success of mTESE from adolescents and adults with KS. The clinical data of 50 late pubertal adolescents (13-19 years) and 85 adult patients (20-61 years) with non-mosaic KS, who underwent mTESE, were analysed with respect to factors, potentially predictive of active spermatogenesis; specifically a history of cryptorchidism, age, testicular volumes, serum levels of LH, FSH, testosterone (T) and estradiol at the time of surgery. Inhibin B, AMH and INSL3 were additionally analysed in the adolescents. A younger age and a near-compensated Leydig cell function were associated with higher success of sperm retrieval via mTESE: In adolescents ≥15-19 years, spermatozoa were retrieved in 45%, compared to 31% in adults; in adolescents aged 13-14 years, spermatozoa were collected in only 10%. Adolescents with an LH ≤17.5 U/L, along with a T level ≥7.5 nmol/L had the best success rate (54%), which fell to 44% with higher LH, whereas those with low T (<7.5 nmol/L), irrespective of LH had no sperm retrieval. In adults with T levels above and LH below these thresholds, the success rate was 51%, falling to 19%, if LH was higher. When T was lower than threshold, the rate was 17%. No association between testicular volumes, serum levels of FSH, Inhibin B, AMH, estradiol and mTESE success was found. A history of cryptorchidism was associated with lower retrieval rates. A window of opportunity for an approximate 50% chance to retrieve spermatozoa via mTESE exists for young, late pubertal KS patients between age 15 and young adulthood, when Leydig cell function is at its best. In these cases, referral to a centre of expertise should be considered.

The CAG repeat polymorphism in the AR gene affects high density lipoprotein cholesterol and arterial vasoreactivity.

Genomic effects of T are exerted via the AR. The length of the polymorphic CAG repeat sequence in the AR gene is inversely correlated with the transcriptional regulation of target genes by T. In 110 healthy men (20-50 yr), we investigated the interactions among this polymorphism, serum levels of sex hormones, cardiovascular risk factors, and flow-mediated and nitrate-induced vasodilatation of the brachial artery. The number of CAG repeat had no significant correlations with serum concentrations of total or free T. Stepwise multiple regression analysis revealed positive correlations of the number of CAG repeat with serum levels of high density lipoprotein cholesterol (partial r = 0.44; P < 0.001) and flow-mediated vasodilatation (partial r = 0.37; P < 0.001). The association of CAG repeat with high density lipoprotein (HDL) cholesterol was independent of body fat content and serum levels of free T, which both had significant negative correlations with HDL cholesterol. The association of CAG repeat with flow-mediated vasodilatation was independent of cigarette smoking and serum levels of free T and low density lipoprotein cholesterol, which also were correlated with flow-mediated vasodilatation. We conclude that a low number of CAG repeat in the AR gene implies a greater chance for low levels of HDL cholesterol and reduced endothelial response to ischemia, which are both important risk factors for coronary heart disease.

Monitoring bone density in hypogonadal men by quantitative phalangeal ultrasound.

Monitoring bone density (BMD) in hypogonadal and testosterone (T) substituted men is a major component of andrological therapy and is performed by methods that are cost-intensive and use radiation, such as quantitative computer tomography (QCT). Therefore, we assessed the feasibility of a more practical and inexpensive approach through application of phalangeal quantitative ultrasound (pQUS; IGEA DBM BP Sonic 1200, Sensweiler, Germany) in a cross-sectional study of 521 men, aged 18-91 years (224 healthy controls, 156 newly diagnosed hypogonadal, and 141 T substituted men). The method was compared with QCT of the lumbar spine in the first 80 patients. We evaluated longitudinal changes of amplitude-dependent speed-of-sound (AdSoS) in 54 hypogonadal men from the beginning of T substitution. AdSoS decreased with age (p < 0.0001) and with declining total T concentration, with a four to fivefold larger reduction in AdSoS for each nanomole-per-liter decrement in total T in the hypogonadal range (<12 nmol/L) compared with the eugonadal range (p < 0.0001). AdSoS was higher in eugonadal and substituted men than in hypogonadal patients (p < 0.0001, by analysis of covariance [ANCOVA]). Substituted men <50 years of age showed lower AdSoS than eugonadal men (p = 0.004) and untreated men with secondary hypogonadism had lower values than men with primary hypogonadism (p = 0.005). Therapeutic effects were seen regardless of age, diagnosis, or T substitution modality. In the longitudinal approach, AdSoS increased from 1986 +/- 93 to 2035 +/- 77 m/sec over 237 +/- 57 days with the highest gain in those men with initially the lowest values (p < 0.0001, by ANCOVA for repeated measurements). In comparison to QCT, patients with a lumbar content of hydroxylapatite of <100 mg/cm(3) were reliably identified by pQUS (cutoff level 1965 m/sec, T score -3.5 based on eugonadal subjects; receiver operating characteristics: area under the curve [AUC] 0.94, sensitivity 94.1, specificity 92%, p < 0.0001), but specific values of lumbar BMD could not be predicted by pQUS. pQUS represents a feasible, sensitive, and inexpensive method for assessing bone tissue in hypogonadal men over the full age range and also for monitoring the effects of T substitution.

Hormone substitution in male hypogonadism.

Male hypogonadism is characterised by androgen deficiency and infertility. Hypogonadism can be caused by disorders at the hypothalamic or pituitary level (hypogonadotropic forms) or by testicular dysfunction (hypergonadotropic forms). Testosterone substitution is necessary in all hypogonadal patients, because androgen deficiency causes slight anemia, changes in coagulation parameters, decreased bone density, muscle atrophy, regression of sexual function and alterations in mood and cognitive abilities. Androgen replacement comprises injectable forms of testosterone as well as implants, transdermal systems, sublingual, buccal and oral preparations. Transdermal systems provide the pharmacokinetic modality closest to natural diurnal variations in testosterone levels. New injectable forms of testosterone are currently under clinical evaluation (testosterone undecanoate, testosterone buciclate), allowing extended injection intervals. If patients with hypogonadotropic hypogonadism wish to father a child, spermatogenesis can be initiated and maintained by gonadotropin therapy (conventionally in the form of human chorionic gonadotropin (hCG) and human menopausal gonadotropin (hMG) or, more recently, purified or recombinant follicle stimulating hormone (FSH)). Apart from this option, patients with disorders at the hypothalamic level can be stimulated with pulsatile gonadotropin-releasing hormone (GnRH). Both treatment modalities have to be administered on average for 7-10 months until pregnancy is achieved. In individual cases, treatment may be necessary for up to 46 months. Testosterone treatment is interrupted for the time of GnRH of gonadotropin therapy, but resumed after cessation of this therapy.

Testosterone levels in healthy men and the relation to behavioural and physical characteristics: facts and constructs.

This review summarises the correlations between testosterone levels and male physical appearance and behaviour. Methodological shortcomings concerning the measurement of testosterone could limit the value of these findings. In addition, testosterone measured in body fluids represents only one step in the cascade of action from production to biological effect, and could therefore provide only a limited view of the complexity of physiological events. Testosterone levels are influenced by conditions that are partly controlled or initiated by the hormone itself, but also by circumstances beyond hormonal or individual control. Different kinds of behaviour are not only subject to influence by environment, but also androgens can reinforce the particular kind of conduct and the behavioural impact can wield negative or positive feedback on testosterone secretion. Therefore, both generalisation and individualisation of study results will lead to doubtful conclusions and prejudices. Results of such studies must be viewed with caution, and over-simplification as well as over-interpretation should be avoided.