Is it time to reconsider how we document pediatric uroflow studies?: A study from the SPU Voiding Dysfunction task force.

BACKGROUND: Uroflowmetry is a non-invasive study used in the diagnosis and monitoring of treatment response for lower urinary tract disorders. For optimal clinical utility, uroflow studies rely on careful clinical interpretation by a trained provider, but currently there is a lack of accepted standardized normal values for the measured uroflow parameters in children. The International Children's Continence Society proposed standardizing the terminology for uroflow curve shapes. However, the patterning of curves is largely at the physician's subjective discretion. OBJECTIVES: The aims of this study were to understand inter-rater reliability in interpreting uroflow curves and to define characteristics of uroflow curves that could be used to provide definitive criteria for uroflowmetry parameters. METHODS: All members of the SPU Voiding dysfunction Task Force were invited to contribute deidentified uroflows to a centralized HIPAA complaint receiving database. All studies were then distributed to all raters for review. Each observer's findings were recorded according to ICCS criteria (ICCS), additional readings were done using a previously reported system which defined curves as smooth or fractionated (SF) and whether the shape resembled a bell, tower, or plateau (BTP). Flow indexes (Qact/Qest) (FI) for Qmax and Qavg were generated using formulas previously reported for children 4-12 and for patients≥12 years. RESULTS: A total of 119 uroflow studies were read by 7 raters and curves were contributed from 5 sites. Kappa scores for the 5 readers from different institutions were 0.34 and 0.28 for the ICCS and BTP methods, respectively (both considered fair agreement). Kappa for smooth and fractionated curves was 0.70 (for each; considered substantial agreement), which were the two highest agreement scores obtained throughout the study. Discriminant analysis (DA) revealed that the FI Qmax was the dominant vector, and that the ICCS uroflow parameters have a total of 42.8% prediction rate in the training sample. Using DA of a smooth/fractionated system, the total prediction rates were 72% and 65.5% for smooth and fractionated, respectively. DISCUSSION: Given the poor inter-rater agreement for analyzing uroflow curve pattern based on ICCS criteria in this study and others, one may find it reasonable to consider alternative approaches to describing and characterizing uroflow curves. Our study is limited by lack of EMG and post-void residual data. CONCLUSIONS: For a more objective uroflow interpretation and comparison of studies among different centers, we recommend using our proposed system (based on FI, and smooth vs. fractionated curve pattern), which is more reliable.

Genomic copy number variation association study in Caucasian patients with nonsyndromic cryptorchidism.

BACKGROUND: Copy number variation (CNV) is a potential contributing factor to many genetic diseases. Here we investigated the potential association of CNV with nonsyndromic cryptorchidism, the most common male congenital genitourinary defect, in a Caucasian population. METHODS: Genome wide genotyping were performed in 559 cases and 1772 controls (Group 1) using Illumina HumanHap550 v1, HumanHap550 v3 or Human610-Quad platforms and in 353 cases and 1149 controls (Group 2) using the Illumina Human OmniExpress 12v1 or Human OmniExpress 12v1-1. Signal intensity data including log R ratio (LRR) and B allele frequency (BAF) for each single nucleotide polymorphism (SNP) were used for CNV detection using PennCNV software. After sample quality control, gene- and CNV-based association tests were performed using cleaned data from Group 1 (493 cases and 1586 controls) and Group 2 (307 cases and 1102 controls) using ParseCNV software. Meta-analysis was performed using gene-based test results as input to identify significant genes, and CNVs in or around significant genes were identified in CNV-based association test results. Called CNVs passing quality control and signal intensity visualization examination were considered for validation using TaqMan CNV assays and QuantStudio® 3D Digital PCR System. RESULTS: The meta-analysis identified 373 genome wide significant (p < 5X10-4) genes/loci including 49 genes/loci with deletions and 324 with duplications. Among them, 17 genes with deletion and 1 gene with duplication were identified in CNV-based association results in both Group 1 and Group 2. Only 2 genes (NUCB2 and UPF2) containing deletions passed CNV quality control in both groups and signal intensity visualization examination, but laboratory validation failed to verify these deletions. CONCLUSIONS: Our data do not support that structural variation is a major cause of nonsyndromic cryptorchidism.

Pathway analysis supports association of nonsyndromic cryptorchidism with genetic loci linked to cytoskeleton-dependent functions.

STUDY QUESTION: What are the genetic loci that increase susceptibility to nonsyndromic cryptorchidism, or undescended testis? SUMMARY ANSWER: A genome-wide association study (GWAS) suggests that susceptibility to cryptorchidism is heterogeneous, with a subset of suggestive signals linked to cytoskeleton-dependent functions and syndromic forms of the disease. WHAT IS KNOWN ALREADY: Population studies suggest moderate genetic risk of cryptorchidism and possible maternal and environmental contributions to risk. Previous candidate gene analyses have failed to identify a major associated locus, although variants in insulin-like 3 (INSL3), relaxin/insulin-like family peptide receptor 2 (RXFP2) and other hormonal pathway genes may increase risk in a small percentage of patients. STUDY DESIGN, SIZE, DURATION: This is a case-control GWAS of 844 boys with nonsyndromic cryptorchidism and 2718 control subjects without syndromes or genital anomalies, all of European ancestry. PARTICIPANTS/MATERIALS, SETTING, METHODS: All boys with cryptorchidism were diagnosed and treated by a pediatric specialist. In the discovery phase, DNA was extracted from tissue or blood samples and genotyping performed using the Illumina HumanHap550 and Human610-Quad (Group 1) or OmniExpress (Group 2) platform. We imputed genotypes genome-wide, and combined single marker association results in meta-analyses for all cases and for secondary subphenotype analyses based on testis position, laterality and age, and defined genome-wide significance as P = 7 × 10(-9) to correct for multiple testing. Selected markers were genotyped in an independent replication group of European cases (n = 298) and controls (n = 324). We used several bioinformatics tools to analyze top (P < 10(-5)) and suggestive (P < 10(-3)) signals for significant enrichment of signaling pathways, cellular functions and custom gene lists after multiple testing correction. MAIN RESULTS AND THE ROLE OF CHANCE: In the full analysis, we identified 20 top loci, none reaching genome-wide significance, but one passing this threshold in a subphenotype analysis of proximal testis position (rs55867206, near SH3PXD2B, odds ratio = 2.2 (95% confidence interval 1.7, 2.9), P = 2 × 10(-9)). An additional 127 top loci emerged in at least one secondary analysis, particularly of more severe phenotypes. Cytoskeleton-dependent molecular and cellular functions were prevalent in pathway analysis of suggestive signals, and may implicate loci encoding cytoskeletal proteins that participate in androgen receptor signaling. Genes linked to human syndromic cryptorchidism, including hypogonadotropic hypogonadism, and to hormone-responsive and/or differentially expressed genes in normal and cryptorchid rat gubernaculum, were also significantly overrepresented. No tested marker showed significant replication in an independent population. The results suggest heterogeneous, multilocus and potentially multifactorial susceptibility to nonsyndromic cryptorchidism. LIMITATIONS, REASONS FOR CAUTION: The present study failed to identify genome-wide significant markers associated with cryptorchidism that could be replicated in an independent population, so further studies are required to define true positive signals among suggestive loci. WIDER IMPLICATIONS OF THE FINDINGS: As the only GWAS to date of nonsyndromic cryptorchidism, these data will provide a basis for future efforts to understand genetic susceptibility to this common reproductive anomaly and the potential for additive risk from environmental exposures. STUDY FUNDING/COMPETING INTERESTS: This work was supported by R01HD060769 (the Eunice Kennedy Shriver National Institute for Child Health and Human Development (NICHD)), P20RR20173 (the National Center for Research Resources (NCRR), currently P20GM103464 from the National Institute of General Medical Sciences (NIGMS)), an Institute Development Fund to the Center for Applied Genomics at The Children's Hospital of Philadelphia, and Nemours Biomedical Research. The authors have no competing interests to declare.

Phenotype specific association of the TGFBR3 locus with nonsyndromic cryptorchidism.

PURPOSE: Based on a genome-wide association study of testicular dysgenesis syndrome showing a possible association with TGFBR3, we analyzed data from a larger, phenotypically restricted cryptorchidism population for potential replication of this signal. MATERIALS AND METHODS: We excluded samples based on strict quality control criteria, leaving 844 cases and 2,718 controls of European ancestry that were analyzed in 2 separate groups based on genotyping platform (ie Illumina® HumanHap550, version 1 or 3, or Human610-Quad, version 1 BeadChip in group 1 and Human OmniExpress 12, version 1 BeadChip platform in group 2). Analyses included genotype imputation at the TGFBR3 locus, association analysis of imputed data with correction for population substructure, subsequent meta-analysis of data for groups 1 and 2, and selective genotyping of independent cases (330) and controls (324) for replication. We also measured Tgfbr3 mRNA levels and performed TGFBR3/betaglycan immunostaining in rat fetal gubernaculum. RESULTS: We identified suggestive (p ≤ 1× 10(-4)) association of markers in/near TGFBR3, including rs9661103 (OR 1.40; 95% CI 1.20, 1.64; p = 2.71 × 10(-5)) and rs10782968 (OR 1.58; 95% CI 1.26, 1.98; p = 9.36 × 10(-5)) in groups 1 and 2, respectively. In subgroup analyses we observed strongest association of rs17576372 (OR 1.42; 95% CI 1.24, 1.60; p = 1.67 × 10(-4)) with proximal and rs11165059 (OR 1.32; 95% CI 1.15, 1.38; p = 9.42 × 10(-4)) with distal testis position, signals in strong linkage disequilibrium with rs9661103 and rs10782968, respectively. Association of the prior genome-wide association study signal (rs12082710) was marginal (OR 1.13; 95% CI 0.99, 1.28; p = 0.09 for group 1), and we were unable to replicate signals in our independent cohort. Tgfbr3/betaglycan was differentially expressed in wild-type and cryptorchid rat fetal gubernaculum. CONCLUSIONS: These data suggest complex or phenotype specific association of cryptorchidism with TGFBR3 and the gubernaculum as a potential target of TGFß signaling.

Altered infant feeding patterns in boys with acquired nonsyndromic cryptorchidism.

BACKGROUND: Genetic and environmental factors likely influence susceptibility to nonsyndromic cryptorchidism, a common disease presenting at birth or in later childhood. We compared cases and controls to define differential risk factors for congenital versus acquired cryptorchidism. METHODS: We compared questionnaire and clinical data from cases of congenital cryptorchidism (n = 230), acquired cryptorchidism (n = 182) and hernia/hydrocele (n = 104) with a group of healthy male controls (n = 358). Potential predictor variables (p < 0.2 in univariable analysis) were included in stepwise multivariable logistic regression models. RESULTS: Temporary (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.4-0.8) or exclusive (OR, 0.6; 95% CI, 0.4-0.9) breastfeeding was reduced and soy formula feeding increased (OR, 1.8; 95% CI, 1.2-2.9) in acquired but not congenital or hernia/hydrocele groups. The highest risk estimates were observed for primary soy formula feeding with limited or no breastfeeding (OR 2.5; 95% CI, 1.4-4.3; adjusted OR, 2.7; 95% CI, 1.4-5.4) in the acquired group. Primary feeding risk estimates were equivalent or strengthened when multivariable models were limited to age greater than 2 years, full-term or not small for gestational age, or Caucasian subjects. Pregnancy complications and increased maternal exposure to cosmetic or household chemicals were not consistently associated with either form of cryptorchidism in these models. CONCLUSIONS: Our data support reduced breastfeeding and soy formula feeding as potential risk factors for acquired cryptorchidism. Although additional studies are needed, hormonally active components of breast milk and soy formula could influence the establishment of normal testis position in the first months of life, leading to apparent ascent of testes in childhood. Birth Defects Research (Part A), 2012.

Reduced expression of androgen receptor and myosin heavy chain mRNA in cremaster muscle of boys with nonsyndromic cryptorchidism.

PURPOSE: To better define the developmental mechanisms of nonsyndromic cryptorchidism, we measured the expression of hormone receptor and muscle type specific mRNAs in target tissues of boys with and those without nonsyndromic cryptorchidism. MATERIALS AND METHODS: Prospectively collected cremaster muscle and/or hernia sac tissues from boys with congenital (79) or acquired (66) nonsyndromic cryptorchidism and hernia/hydrocele (controls, 84) were analyzed for hormone receptor (RXFP2, AR, ESR1, ESR2) and myosin heavy chain specific (MYH1, MYH2, MYH7) mRNA expression using real-time reverse transcriptase polymerase chain reaction. Log transformed mRNA, phenotype and feeding history data were statistically analyzed using Pearson's correlation, ANOVA and 2-sample t tests. RESULTS: AR mRNA expression was higher in cremaster muscle than in sac tissue, and significantly lower in congenital and acquired nonsyndromic cryptorchidism cases vs controls (p <0.01). Type 1 (slow/cardiac) MYH7 mRNA expression was also significantly reduced in both nonsyndromic cryptorchidism groups (p ≤ 0.002), while a reduction in type 2 (fast) MYH2 expression was more modest and significant only for the congenital cryptorchidism group (p <0.05). Cremasteric MYH7 and AR levels were strongly correlated (r(2) = 0.751, p <0.001). MYH7 and ESR1 mRNA levels were higher and lower, respectively, in boys with nonsyndromic cryptorchidism who were fed soy formula. Expression of other genes was not measurable. CONCLUSIONS: Our data suggest that boys with congenital and acquired nonsyndromic cryptorchidism differentially express AR and slow twitch specific MYH7 mRNA in the cremaster muscle, and that MYH7 expression is correlated with AR levels and soy formula use. These differences in gene expression may reflect aberrant hormonal signaling and/or innervation during development with the potential for secondary functional effects and failed testicular descent.

Management of nephrolithiasis after Cohen cross-trigonal and Glenn-Anderson advancement ureteroneocystostomy.

PURPOSE: Ureteroneocystotomy is frequently performed for ureteral injury or vesicoureteral reflux. The Glenn-Anderson technique advances the ureteral orifice distal to its native position, while the Cohen technique crosses the orifice to the opposite trigone. Each treatment can alter access to the upper genitourinary tracts. We report our experience with subsequent nephrolithiasis in these patients. MATERIALS AND METHODS: We performed a retrospective chart review of all patients treated with ureteroneocystotomy since 1980 who had nephrolithiasis. RESULTS: Nephrolithiasis developed in 9 patients with prior Cohen ureteroneocystotomy and in 15 with prior Glenn-Anderson ureteroneocystotomy. Stones size was 2 to 20 mm (mean 6.4). In the Cohen group ureteroscopy was attempted and failed in 2 patients, requiring percutaneous nephrolithotomy. Attempted shock wave lithotripsy failed in 2 patients, of whom 1 required percutaneous nephrolithotomy and 1 required observation. Primary percutaneous nephrolithotomy was performed in 1 patient. One patient required nephrectomy for chronic pyelonephritis related to nephrolithiasis. Two patients had active stone disease and were awaiting further treatment, while 1 passed the stone. In the Glenn-Anderson group ureteroscopy was successful in all 4 attempts. Attempted shock wave lithotripsy in 2 patients was successful in 1. The other patient required subsequent percutaneous nephrolithotomy. Primary percutaneous nephrolithotomy was required in 2 patients. All other patients were asymptomatic and under observation. CONCLUSIONS: Treatment for upper tract nephrolithiasis is effected by prior ureteroneocystotomy. Minimally invasive treatments were less successful after Cohen ureteroneocystotomy than after Glenn-Anderson ureteroneocystotomy. In this study patients with prior cross-trigonal ureteroneocystotomy required more invasive therapies for symptomatic nephrolithiasis.