The Prevalence, Clinicodemographics, and Outcomes of Incidental and Symptomatic Renal Cysts in a Pediatric Cohort Undergoing Ultrasonography.

PURPOSE: The growing availability of modern-day imaging has resulted in an increase in the number of renal cysts detected in the pediatric population. Few publications have reported outcomes of these childhood cysts. In this study we assessed the prevalence and evolution of renal cysts in children, and described clinical characteristics, mode of presentation and ultimate outcomes. MATERIALS AND METHODS: Our institutional ultrasound database was searched for all abdominal ultrasound reports from 2006 to 2017. These reports were then cross-referenced with a manual retrospective chart review. Clinical characteristics including mode of presentation, cyst characteristics, and outcomes were analyzed using descriptive and nonparametric statistical methods. RESULTS: Of 70,500 abdominal ultrasound scans during the study period 1,531 (2.2%) met the study inclusion criteria. Overall 26% of cysts were complex and 10.1% of cases were associated with hydronephrosis. Echogenic kidneys were more likely to be associated with simple cysts (p=0.0001). There was no difference between cyst diameter and symptomatology (p=0.82). The conversion of simple to complex renal cysts was less than 1% and 1.8% of complex cysts developed renal cell carcinoma. CONCLUSIONS: In a large cohort of children who underwent abdominal imaging we found a 10-year renal cyst prevalence of 2.2%. Given that nearly all cysts follow a benign course and that simple cysts will invariably grow within 2 years, we believe that these cases could be safely discharged after that point. We continue to recommend surveillance for patients with cysts larger than 15 mm, complex cysts, family history of adult polycystic kidney disease or those with concomitant genitourinary anomalies requiring ongoing followup.

Urodynamic testing--is it a useful tool in the management of children with cutaneous stigmata of occult spinal dysraphism?

PURPOSE: Lumbar cutaneous stigmata in infants may be associated with occult spinal dysraphism and often prompt urological evaluation, including urodynamic testing. We examined whether urodynamic testing is useful in this population by evaluating the association between abnormal urodynamic test results and need for tethered cord release. MATERIALS AND METHODS: We reviewed a historical cohort of children with cutaneous stigmata of spinal dysraphism referred to our hospital from 2002 to 2010. We evaluated patient characteristics, imaging, urodynamic studies and neurosurgical interventions. We analyzed the association between urodynamic testing and imaging studies, and neurosurgical intervention. RESULTS: We retrospectively studied 123 patients with a median age of 11 months (IQR 6.5-15.5), including 112 nontoilet trained infants (91%). Of the patients 19% (23 of 123) had abnormal urodynamics, 85% (99 of 116) had abnormal spinal magnetic resonance imaging and 96% (98 of 102) had an abnormal spinal ultrasound. Tethered cord release was performed in 40 of 121 patients (33%). A significant association was found between abnormal urodynamics and neurosurgical intervention (p = 0.002). Abnormal spinal magnetic resonance imaging was also significantly associated with operative intervention (p = 0.05). Ultrasound of the spine (p = 1.0), ultrasound of the abdomen/pelvis (p = 0.68), history of urinary tract infections (p = 1.0) and constipation (p = 0.67) were not associated with intervention for tethered cord release. CONCLUSIONS: Abnormal urodynamic studies in infants with cutaneous stigmata of spinal dysraphism are significantly associated with the requirement for neurosurgical intervention. Urodynamics are an important diagnostic modality aiding the neurosurgeon in determining the need for surgical intervention in this population.

Differential expression of somatostatin genes in the central nervous system of the sea lamprey.

The identification of three somatostatin (SST) genes (SSTa, SSTb, and SSTc) in lampreys (Tostivint et al. Gen Comp Endocrinol 237:89-97 https://doi.org/10.1016/j.ygcen.2016.08.006 , 2016) prompted us to study their expression in the brain and spinal cord of the sea lamprey by in situ hybridization. These three genes were only expressed in equivalent neuronal populations in the hypothalamus. In other regions, SST transcripts showed clear differential expression. In the telencephalon, SSTc-positive cells were observed in the medial pallium, ventral part of the lateral pallium, striatum, subhippocampal lobe, and preoptic region. In the diencephalon, SSTa-positive cells were observed in the thalamus and SSTc-positive cells in the prethalamus, posterior tubercle, pretectal area, and nucleus of the medial longitudinal fascicle. In the midbrain, SSTc-positive cells were observed in the torus semicircularis, lateral reticular area, and perioculomotor tegmentum. Different SSTa- and SSTc-positive populations were observed in the isthmus. SSTc neurons were also observed in the rostral octavolateralis area and caudal rhombencephalon. In the spinal cord, SSTa was expressed in cerebrospinal-fluid-contacting (CSF-c) neurons and SSTc in non-CSF-c interneurons. Comparison with previous immunohistochemical studies using anti-SST-14 antibodies strongly suggests that SST-14-like neurons correspond with the SSTa populations. Thus, the SSTc populations were not reported previously in immunohistochemical studies. Cluster-based analyses and alignments of mature peptides suggested that SSTa is an ortholog of SST1 and that SSTb is closely related to SST2 and SST6. These results provide important new insights into the evolution of the somatostatinergic system in vertebrates.

Is staging beneficial for Fowler-Stephens orchiopexy? A systematic review.

PURPOSE: Fowler and Stephens showed that by dividing the spermatic vessels a high intra-abdominal testis could be placed in the scrotum. Testicular atrophy is a potential complication of this technique. We conducted a systematic review to determine whether single or 2-stage Fowler-Stephens orchiopexy results in better testicular viability. MATERIALS AND METHODS: We searched electronic databases, clinical trial registries and gray literature. We included reports describing boys younger than 18 years with a primary outcome of "testicular viability and position." We performed a meta-analysis using random effects models. Heterogeneity was assessed using forest plot and I(2) statistic. RESULTS: We identified 1,807 citations and included 61 articles. Single stage Fowler-Stephens orchiopexy was discussed in 9 articles, a 2-stage procedure in 36 and both approaches in 16. There were no randomized controlled trials, and most studies were cohort or case series. The pooled estimate of success rates was 80% for single stage Fowler-Stephens orchiopexy (95% CI 75 to 86) and 85% for 2-stage Fowler-Stephens orchiopexy (95% CI 81 to 90). The pooled odds ratio of single stage vs 2-stage Fowler-Stephens orchiopexy was 2.0 (95% CI 1.1 to 3.9) favoring the 2-stage procedure. There was no difference in the success rate between laparoscopic and open techniques in either single or 2-stage Fowler-Stephens orchiopexy. There was no evidence of asymmetry on the funnel plot. There were no complications reported with single stage, while ileus, hematoma and infection were the most common complications with 2-stage Fowler-Stephens orchiopexy. CONCLUSIONS: Both techniques have a fairly high success rate but 2-stage Fowler-Stephens orchiopexy appears to carry a higher rate of success than the single stage approach (85% vs 80%, OR 2 in favor of 2-stage). Laparoscopic and open techniques had the same success rate. However, the level of evidence of the studies was low, and a study of a more robust design, such as a randomized controlled trial, should be performed.

Cholecystokinin in the central nervous system of the sea lamprey Petromyzon marinus: precursor identification and neuroanatomical relationships with other neuronal signalling systems.

Cholecystokinin (CCK) is a neuropeptide that modulates processes such as digestion, satiety, and anxiety. CCK-type peptides have been characterized in jawed vertebrates and invertebrates, but little is known about CCK-type signalling in the most ancient group of vertebrates, the agnathans. Here, we have cloned and sequenced a cDNA encoding a sea lamprey (Petromyzon marinus L.) CCK-type precursor (PmCCK), which contains a CCK-type octapeptide sequence (PmCCK-8) that is highly similar to gnathostome CCKs. Using mRNA in situ hybridization, the distribution of PmCCK-expressing neurons was mapped in the CNS of P. marinus. This revealed PmCCK-expressing neurons in the hypothalamus, posterior tubercle, prethalamus, nucleus of the medial longitudinal fasciculus, midbrain tegmentum, isthmus, rhombencephalic reticular formation, and the putative nucleus of the solitary tract. Some PmCCK-expressing neuronal populations were only observed in adults, revealing important differences with larvae. We generated an antiserum to PmCCK-8 to enable immunohistochemical analysis of CCK expression, which revealed that GABA or glutamate, but not serotonin, tyrosine hydroxylase or neuropeptide Y, is co-expressed in some PmCCK-8-immunoreactive (ir) neurons. Importantly, this is the first demonstration of co-localization of GABA and CCK in neurons of a non-mammalian vertebrate. We also characterized extensive cholecystokinergic fibre systems of the CNS, including innervation of habenular subnuclei. A conspicuous PmCCK-8-ir tract ascending in the lateral rhombencephalon selectively innervates a glutamatergic population in the dorsal isthmic grey. Interestingly, this tract is reminiscent of the secondary gustatory/visceral tract of teleosts. In conclusion, this study provides important new information on the evolution of the cholecystokinergic system in vertebrates.

Renal cyst evolution in childhood: a contemporary observational study.

INTRODUCTION: Children with renal cysts often undergo ultrasound (US) monitoring to identify malignant transformation or polycystic kidney disease (PKD). However, the utility of ongoing surveillance is uncertain. OBJECTIVE: The objective of this study was to assess the natural history of simple or minimally complex cysts and the proportion of progression to autosomal dominant polycystic kidney disease (ADPKD), autosomal recessive polycystic kidney disease (ARPKD), or malignancy. STUDY DESIGN: The institutional review board approved retrospective chart review at one institution between 2004 and 2014. Eligible patients had ≤3 simple or minimally complex cyst(s) discovered on US without an initial diagnosis of multicystic dysplastic kidney, genitourinary malignancy, ADPKD, or ARPKD. Patient demographics and cyst details were recorded at identification and follow-up visits. Logistic regression was used to examine univariate association between diagnosis of ADPKD/ARPKD and each recorded variable. RESULTS: Eighty-seven eligible patients were identified. Twenty-two patients were identified antenatally or in the first year of life; the remaining 65 were identified at >1 year of age, median 7.6 years (interquartile range [IQR]: 4.2, 10.6). Most (60/87, 69%) had a solitary cyst at initial US. The median length of follow-up was 4.1 years (IQR: 1.9, 6.8) with median 3 follow-up US (IQR: 2, 5). Eleven patients (12.6%) were diagnosed with ADPKD. One patient (1.2%) was diagnosed with ARPKD. A median 2 follow-up US (IQR: 1, 4) procedures were performed over a median of 2.2 years (IQR: 1.0, 3.9) to obtain diagnoses of ADPKD or ARPKD. No patients developed malignancy. DISCUSSION: This study's results reveal that children identified to have a small number of simple or minimally complex renal cysts on initial US are unlikely to require additional treatment for these cysts as transformation to PKD or malignant condition is rare. Supporting this are results from literature that although simple cysts in childhood may evolve over time, most do not require any surgical or invasive treatment in the long term. Limitations include retrospective design and single institution. CONCLUSIONS: Autosomal dominant polycystic kidney disease/autosomal recessive polycystic kidney disease diagnosis occurs early in follow-up evaluation in children with simple or minimally complex cysts. Malignant transformation did not occur in any patients in this study. PATIENT SUMMARY: This study examines the natural history of renal cysts in childhood. Following up simple renal cysts routinely beyond 2-3 years after initial detection may not be optimal due to the use of limited medical resources.

Reliability assessment of Society for Fetal Urology ultrasound grading system for hydronephrosis.

PURPOSE: The Society for Fetal Urology introduced a subjective grading system for classifying hydronephrosis that has important implications in patient diagnosis, treatment and outcome. The grading system is frequently used to standardize the severity of hydronephrosis, and compare results among patients and centers. Despite widespread use to our knowledge no groups have investigated the reliability of the grading system since its introduction. We assessed the intrarater and interrater reliability of the Society for Fetal Urology grading system for hydronephrosis and examined levels of agreement by the degree of hydronephrosis (grades 0 to 4) and level of experience (staff vs trainee). MATERIALS AND METHODS: A series of 50 pediatric renal ultrasound images from patients with a diagnosis of hydronephrosis were assessed by 4 staff individuals and 4 trainees using the Society for Fetal Urology grading system. Ultrasound images included the kidneys, ureters and bladder to be consistent with practice. After 7 to 14 days each rater repeated the assessment. The nonweighted Cohen kappa statistic was used to estimate intrarater and interrater reliability by Society for Fetal Urology grade and training level. RESULTS: Staff and trainee raters independently assigned Society for Fetal Urology grades to 50 patients (99 renal units). The average number of images per ultrasound was 41, including the right and left kidneys. Overall interrater agreement for staff individuals was substantial for grade 0, moderate for grades 1, 2 and 4, and only slight to fair for grade 3. Intrarater agreement was substantial to almost perfect for staff agreement (range 69% to 94%, kappa 0.56 to 0.89) and trainees (range 63% to 90%, kappa 0.48 to 0.85). CONCLUSIONS: Our study suggests that the Society for Fetal Urology grading system has good intrarater but modest interrater reliability. Individual rater interpretations of the grading system may explain the modest interrater agreement. Proposed modifications to the Society for Fetal Urology classification system, such as distinguishing between diffuse and segmental cortical thinning, may improve reliability.

Nerve growth factor in skeletal tissues of the embryonic chick.

This study demonstrates, via immunohistochemistry and bioassay, the presence of NGF in embryonic bone and cartilage of the chick. Embryos were killed on days 6-9 of incubation at 12 h intervals, and on days 10-18 at 24 h intervals. Paraffin-embedded sections of hind limbs or buds were immunostained with a polyclonal antibody against NGF and the biotin-avidin-horseradish peroxidase technique. Immunostaining was positive in both bone and cartilage, with cartilage staining more intensely. For bioassay, bones from the hind limbs of 9- and 12-day embryos were fast-frozen, lyophilized, and homogenized with Medium 199 (M199). Dorsal root ganglia from 8-day embryos were cultured for 24-36 h with rooster plasma, M199, and varying concentrations of bone homogenate. Significant neurite outgrowth was seen, with the greatest response elicited by 12-day bone homogenate. Addition of anti-NGF to the cultures abolished neurite outgrowth. The results indicate that NGF is present in cartilage and bone of the chick embryo; it may determine the density of sympathetic innervation to the developing skeletal tissues.