Recovery of testicular spermatozoa from azoospermic patients with testicular failure followed by intracytoplasmic sperm injection (ICSI) is a recent advance in the treatment of male infertility. This study aimed at investigating which parameter(s) may predict successful testicular sperm recovery. We reviewed 395 testicular sperm recovery procedures and analysed the most frequently available parameters for clinical decision-making in azoospermic patients: (i) presence of at least one single spermatozoon in at least one preliminary semen analysis; (ii) maximum testicular volume; (iii) serum follicle stimulating hormone (FSH); and (iv) presence of spermatozoa in the histology of a randomly-taken testicular biopsy. Sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio and accuracy were calculated for the above index parameters in different clinically relevant subgroups using receiver operating characteristic (ROC) curves whenever possible. Spermatozoa were always successfully recovered in patients with normal testicular histological findings (n = 173) or hypospermatogenesis (n = 16) but not in some patients with tubular sclerosis (seven out of 18), Sertoli cell-only pattern (55 out of 112) or maturation arrest (39 out of 76). Histopathology was the best test for predicting successful sperm recovery in the whole population (sensitivity: 86%, specificity: 93%, accuracy: 0.87). In patients with secretory azoospermia, histopathology was again the most accurate parameter (accuracy: 0.74), especially in patients showing Sertoli cell-only pattern (accuracy: 0.83) but not in patients showing maturation arrest (accuracy: 0.55). In patients with serum FSH concentrations > 12 IU/l and maximum testicular volume < 15 ml, histopathology was not found to be accurate. Semen analysis, maximum testicular volume and serum FSH were not highly predictive in all subgroups studied. Our analysis shows that no strong predictors for successful testicular sperm recovery are available except for testicular histopathology.

It has been suggested that the prevalence of Helicobacter pylori infection has stabilized in the USA and is decreasing in China. We conducted a systematic literature analysis to test this hypothesis. PubMed and Embase searches were conducted up to 19 January 2015. Trends in the prevalence of H. pylori infection over time were assessed by regression analysis using Microsoft Excel. Overall, 25 Chinese studies (contributing 28 datasets) and 11 US studies (contributing 11 datasets) were included. There was a significant decrease over time in the H. pylori infection prevalence for the Chinese studies overall (p = 0.00018) and when studies were limited to those that used serum immunoglobulin G (IgG) assays to detect H. pylori infection (p = 0.014; 20 datasets). The weighted mean prevalence of H. pylori infection was 66 % for rural Chinese populations and 47 % for urban Chinese populations. There was a significant trend towards a decreasing prevalence of H. pylori infection for studies that included only urban populations (p = 0.04; 9 datasets). This trend was no longer statistically significant when these studies were further restricted to those that used serum IgG assays to detect H. pylori infection, although this may have been because of low statistical power due to the small number of datasets available for this analysis (p = 0.28; 6 datasets). There were no significant trends in terms of changes in the prevalence of H. pylori infection over time for studies conducted in the USA. In conclusion, the prevalence of H. pylori infection is most likely decreasing in China, due to a combination of increasing urbanization, which we found to be associated with lower H. pylori infection rates, and possibly also decreasing rates of H. pylori infection within urban populations. This will probably result in a gradual decrease in peptic ulcer and gastric cancer rates in China over time.Electronic supplementary materialThe online version of this article (doi:10.1186/s13099-016-0091-7) contains supplementary material, which is available to authorized users.

SUMMARY BackgroundProton pump inhibitors (PPIs) have a well-established safety profile. However, concerns have been raised about a potential relationship between PPI-induced hypergastrinaemia and the development of enterochromaffinlike (ECL) cell hyperplasia, neuroendocrine tumours and gastric cancer during long-term therapy.

A comprehensive study is presented of a series of 124 infertile men undergoing testicular sperm retrieval for intracytoplasmic sperm injection (ICSI). In this study we correlated the histological changes observed in the testicular tissue with the results of the wet preparation and the outcome after ICSI using testicular spermatozoa. In all patients with normal spermatogenesis and hypospermatogenesis spermatozoa were recovered from the wet preparation. The sperm recovery rate as 84% in patients with incomplete germ-cell-aplasia and maturation arrest, while in patients with complete germ-cell aplasia or maturation arrest this figure was 76%. In these patients more specimens were sampled and fewer spermatozoa were recovered. Since no spermatozoa were recovered in only 10 patients, ICSI with testicular sperm was performed in the remaining 114 couples (91.9%). The normal fertilization rate was 57. 8%. The fertilization rate was significantly lower in couples among whom the husband showed germ-cell aplasia and maturation arrest. Overall, 55.2% of normally fertilized oocytes developed into embryos showing <=50% of anucleate fragments. There were no major differences between the different histological categories in terms of embryonic development in vitro. The overall pregnancy rates per testicular sperm extraction (TESE) procedure, per ICSI procedure and per transfer were respectively 36.3, 39.5 and 43.7%. The overall implantation rate per embryo (sacs/embryos replaced) was 20.3%. A lower implantation rate was observed in couples among whom the husband had maturation arrest (not statistically significant). The above data show that testicular biopsies may have an important therapeutic role in the management of infertility in azoospermic patients.

Testicular biopsy has been widely used for the diagnosis of male infertility. Since the introduction of intracytoplasmic sperm injection (ICSI), spermatozoa recovered from a testicular biopsy specimen can be successfully used for establishing pregnancies. A few spermatozoa may be recovered from a wet preparation of a testicular biopsy, not only in obstructive azoospermic patients, but also in many patients with non-obstructive azoospermia. In 36 out of 38 non-obstructive azoospermic patients sperm cells were recovered from a testicular biopsy specimen. However in two patients, spermatozoa could not be found after further preparation of the biopsy specimens for ICSI. In the remaining 32 patients, a normal fertilization rate of 56.8% per successfully injected oocyte was obtained after ICSI of testicular spermatozoa. In 84% of patients, embryos were replaced with an overall pregnancy rate of 28.9% per testicular biopsy or 34.3% per embryo transfer. The results clearly indicate that at present an excisional testicular biopsy should be offered to all azoospermic patient, irrespective of concentration of follicle stimulating hormone, testicular size or medical history.