ABSTRACT
<p><b>OBJECTIVE</b>To investigate the values of single or repeated luteinizing hormone (LH) releasing hormone analogue (triptorelin) stimulating test in the differential diagnosis between idiopathic hypogonadotropic hypogonadism (IHH) and constitutional delayed puberty (CDP).</p><p><b>METHODS</b>Male patients (n = 133) without puberty onset after the age of 14 were recruited for triptorelin stimulating test and were followed up for 24 - 48 months until the diagnosis were confirmed: 86 were IHH and the other 47 were CDP. Repeated triptorelin stimulating tests were conducted in 9 IHH patients and 13 CDP patients one year after the first stimulating tests with an attempt to evaluate the dynamic change of hypothalamus-pituitary-testis axis function. The relationship between the final diagnosis and the peak LH value (LH(max)), and the changes of repeated LH(max) were investigated.</p><p><b>RESULTS</b>In the single triptorelin stimulating test, LH(max) was (1.9 +/- 1.2) U/L in IHH group, which was significantly lower than that in CDP group [(13.7 +/- 8.3) U/L] (P < 0.01); 75 IHH patients (87.2%) had a LH(max) lower than 4 U/L, while only 2 CDP patients (4.3%) had a LH(max) lower than 4 U/L. When LH(max) < 4U/L was used as a criteria for the diagnosis of IHH, the single triptorelin stimulating test had a sensitivity of 87.2%, a specificity of 95.7%, and a positive predictive value of 97.4%. The repeated triptorelin stimulating tests performed one year later showed that the LH(max) in the 9 IHH patients increased from (4.7 +/- 2.5) U/L to (5.1 +/- 3.3) U/L (P = 0.78), while that in the 13 CDP patients increased from (10.7 +/- 3.3) U/L to (24.5 +/- 5.7) U/L (P < 0.05).</p><p><b>CONCLUSIONS</b>A single triptorelin stimulating test is highly effective in differentiating IHH from CDP. For some patients without definitive diagnosis, a repeated triptorelin stimulating test performed one year later may provide more valuable information on the dynamic change of the hypothalamus-pituitary-testis axis function.</p>
Subject(s)
Adolescent , Adult , Humans , Male , Young Adult , Diagnosis, Differential , Follow-Up Studies , Hypogonadism , Diagnosis , Puberty, Delayed , Diagnosis , Triptorelin PamoateABSTRACT
<p><b>BACKGROUND</b>Many clinical studies suggest the inverse relationship between testosterone levels and insulin sensitivity in men, however the causative relationship of these two events is still not determined. The purpose of this study was to investigate the effects of testosterone replacement therapy (TRT) on insulin sensitivity, body composition, serum lipid profiles and high sensitivity C-reactive protein (hsCRP) in hypogonadotropic hypogonadal (HH) puberty undeveloped male patients.</p><p><b>METHODS</b>In this prospectively designed study, we compared homeostasis model assessment of insulin resistance (HOMA-IR), insulin areas under the curves (AUC) of 3-hour oral glucose tolerance test (OGTT) and other metabolic parameters between 26 HH patients and 26 healthy men. The patients' HOMA-IR, insulin AUC, body composition, lipid profiles, hsCRP and other parameters were compared before and after nine-month TRT.</p><p><b>RESULTS</b>The average levels of total testosterone (TT) in HH and healthy group were (0.9 +/- 0.6) nmol/L and (18.8 +/- 3.4) nmol/L, respectively. HOMA-IR in HH group was significantly higher than the healthy group (5.14 +/- 5.16 vs 2.00 +/- 1.38, P < 0.005). Insulin AUC in 3-hour OGTT in HH group was significantly higher than the healthy group (698.6 +/- 414.7 vs 414.2 +/- 267.5, P < 0.01). Fasting glucose level in HH group was significantly higher than control group ((5.1 +/- 0.6) mmol/L vs (4.7 +/- 0.3) mmol/l, P < 0.005). Height, weight and grasp strength of the patients were significantly increased after 9-month TRT. Significant reductions in HOMA-IR (from 5.14 +/- 5.16 to 2.97 +/- 2.16, P < 0.01), insulin AUC (from 698.6 +/- 414.7 to 511.7 +/- 253.9, P < 0.01) and hsCRP (from (1.49 +/- 1.18) mg/L to (0.70 +/- 0.56) mg/L, P < 0.05) were found after TRT. Serum total cholesterol, LDL-C, HDL-C and triglyceride were all decreased, albeit with no significant difference compared to the level prior to TRT.</p><p><b>CONCLUSIONS</b>HOMA-IR, insulin AUC and fasting glucose level in HH young male patients were significantly higher than those of the control group, which suggests that low level of testosterone in male adolescents might be a risk factor for insulin resistance. TRT can significantly improve patients' insulin sensitivity and suppress serum hsCRP, which in return suggests that TRT may prevent the HH patients from developing diabetes mellitus and cardiovascular diseases (CVD) in future.</p>