Mesenchymal stem cells protect against obstruction-induced renal fibrosis by decreasing STAT3 activation and STAT3-dependent MMP-9 production.

STAT3 is a transcription factor implicated in renal fibrotic injury, but the role of STAT3 in mesenchymal stem cell (MSC)-induced renoprotection during renal fibrosis remains unknown. We hypothesized that MSCs protect against obstruction-induced renal fibrosis by downregulating STAT3 activation and STAT3-induced matrix metalloproteinase-9 (MMP-9) expression. Male Sprague-Dawley rats underwent renal arterial injection of vehicle or MSCs (1 × 106/rat) immediately before sham operation or induction of unilateral ureteral obstruction (UUO). The kidneys were harvested after 4 wk and analyzed for collagen I and III gene expression, collagen deposition (Masson's trichrome), fibronectin, α-smooth muscle actin, active STAT3 (p-STAT3), MMP-9, and tissue inhibitor of matrix metalloproteinases 1 (TIMP-1) expression. In a separate arm, the STAT3 inhibitor S3I-201 (10 mg/kg) vs. vehicle was administered to rats intraperitoneally just after induction of UUO and daily for 14 days thereafter. The kidneys were harvested after 2 wk and analyzed for p-STAT3 and MMP-9 expression, and collagen and fibronectin deposition. Renal obstruction induced a significant increase in collagen, fibronectin, α-SMA, p-STAT3, MMP-9, and TIMP-1 expression while exogenously administered MSCs significantly reduced these indicators of obstruction-induced renal fibrosis. STAT3 inhibition with S3I-201 significantly reduced obstruction-induced MMP-9 expression and tubulointerstitial fibrosis. These results demonstrate that MSCs protect against obstruction-induced renal fibrosis, in part, by decreasing STAT3 activation and STAT3-dependent MMP-9 production.

[A CASE OF DEXTRANOMER-HYALURONIC ACID COPOLYMER (Deflux®) IMPLANTS CALCIFICATION MIMICKING DISTAL URETERAL CALCULI].

Since 2011, endoscopic correction of vesicoureteral reflux using dextranomer-hyaluronic acid copolymer (Deflux®) has been widely accepted in Japan due to its safety and minimally invasive nature. However, long-term complications are unknown. We present a case of Deflux® implants calcification mimicking distal ureteral calculi in a 12-year-old boy with a history of Deflux® injection performed at three years of age for primary VUR. We should be aware of this complication to avoid misdiagnosis and unnecessary invasive examination such as radiological imaging or endoscopy.

[A CASE OF PARATESTICULAR FIBROUS HAMARTOMA OF INFANCY].

Fibrous hamartoma of infancy (FHI) is a rare, benign soft tissue tumor arising from subcutaneous tissue in children during the first two years of life. The tumor is commonly found in the axilla, shoulder and upper arm. Paratesticular FHI is extremely rare. To date, only a case of paratesticular FHI has been reported in Japan. We present a case of paratesticular FHI in an 11-month-old boy who eventually needed orchiectomy due to local recurrence one month after the excision of the tumor. Ten months postoperatively, there was no sign of recurrence.

IL-18 induces profibrotic renal tubular cell injury via STAT3 activation.

IL-18 is an important mediator of obstruction-induced renal fibrosis and renal tubular epithelial cell (TEC) injury. IL-18's proinflammatory properties have been attributed, in part, to NF-κB activation and the stimulation of cytokine gene expression; however, STAT3 has increasingly been shown to mediate renal fibrotic injury. We therefore hypothesized that IL-18 mediates profibrotic TEC injury via STAT3 activation. Male C57BL6 wild-type mice and transgenic mice for human IL-18-binding protein were subjected to unilateral ureteral obstruction or sham operation. The kidneys were harvested 1 or 2 wk afterward and analyzed for active STAT3 (p-STAT3) expression (Western blotting, immunohistochemistry) and suppressor of cytokine signaling 3 (SOCS3) expression. In a separate arm, renal tubular cells (HK-2) were directly stimulated with IL-18 for 2 days with or without the STAT3 inhibitor S3I-201 (50 µM). Cell lysates were then analyzed for p-STAT3 and SOCS3 expression, profibrotic cellular changes (collagen and α-SMA expression), and tubular cell apoptosis. p-STAT3 and SOCS3 expression increased significantly in response to obstruction; however, a significant reduction in p-STAT3 and SOCS3 expression occurred following 1 wk, but not 2 wk, of obstruction in the presence of IL-18 neutralization. In vitro results similarly demonstrate increased p-STAT3, SOCS3, α-SMA, and collagen III expression, and increased collagen production and TEC apoptosis in response to IL-18 stimulation, but the response was significantly diminished in the presence of STAT3 inhibition. These results demonstrate that IL-18-induces profibrotic cellular changes and collagen production in TECs via STAT3 activation.

IL-18 activation is dependent on Toll-like receptor 4 during renal obstruction.

PURPOSE: Interleukin 18 (IL-18) is a critical mediator of obstruction-induced renal injury. Although previous studies have demonstrated that IL-18 participates in a positive feedback loop via the IL-18 receptor (IL-18R) and localized renal IL-18 and IL-18R production to tubular epithelial cells (TEC), the mechanism of IL-18 activation during obstruction remains unclear. We hypothesized that IL-18 activation is dependent on Toll-like receptor 4 (TLR4) signaling during renal obstruction. MATERIALS AND METHODS: Male C57BL6 TLR4 knockout (TLR4KO) and wild-type (WT) mice were subjected to unilateral ureteral obstruction versus sham operation for 1 wk. The animals were sacrificed, and renal cortical tissue was harvested and analyzed for TLR4 expression (Western blot), active IL-18 production (enzyme-linked immunosorbent assay, real-time polymerase chain reaction), IL-18 receptor expression (real-time polymerase chain reaction), and TLR4/IL-18 versus IL-18R cellular localization (dual immunofluorescent staining). RESULTS: Renal TLR4 expression increased significantly in WT mice in response to obstruction, but remained at sham treatment levels in TLR4KO mice. IL-18 and IL-18R gene expression and active IL-18 production were similarly increased in WT mice in response to obstruction, but decreased significantly to sham treatment levels in the absence of TLR4. Dual immunofluorescent staining revealed co-localization of TLR4 and IL-18 to renal TEC during obstruction. CONCLUSION: IL-18 production and activation during renal obstruction is dependent on intact TLR4 signaling. Co-localization of IL-18 and TLR4 production to TEC during obstruction suggests that TEC are the primary site of IL-18 production and activation. Further characterization of the pathway may be necessary to develop targeted therapy in obstruction-induced renal injury.

A Case of Solitary Kidney and Single-system Ectopic Ureter Draining Into the Vestibule in an Infant With Müllerian Duct Defect: Was the Bladder Missing?

We report a case of a solitary kidney and a single-system ectopic ureter draining into the vestibule in an infant with a Müllerian duct defect. Due to the absence of the upper vagina and uterus, an extremely underdeveloped bladder masqueraded as the vagina, and bladder agenesis was suspected preoperatively. Urinary continence was achieved using staged bladder surgery without augmentation or urinary diversion.

Prenatally diagnosed giant umbilical cord resulted from patent urachus in a monochorionic diamniotic twin with selective intrauterine growth restriction.

A long diffuse giant umbilical cord (GUC), caused by umbilical cord edema associated with a patent urachus, is an extremely rare anomaly. While patients with diffuse GUC appear to experience no significant complications and a good prognosis, little is known about their etiology and prenatal course. Here, we report the first case of prenatally diagnosed diffuse GUC resulted from patent urachus in a monochorionic diamniotic twin with selective intrauterine growth restriction. This case indicates that GUC is epigenetic and unrelated to multiple births.

Unilateral renal agenesis and ipsilateral absence of the vas deferens in a cryptorchid infant with Klippel-Feil syndrome.

We report an exceedingly rare case of Klippel-Feil syndrome (KFS), compounded by ipsilateral absence of the vas deferens, renal agenesis, and diaphragmatic hernia. Unilateral absence of the vas deferens was found incidentally during orchidopexy. To the best of our knowledge, no case of unilateral absence of the kidney and vas deferens has been reported in children with KFS.

Prenatally Detected Intrascrotal Testicular Teratoma in an Infant.

Although teratomas are the most common tumors in the testes of prepubertal children, prenatally detected testicular teratomas are extremely rare. To date, only 6 cases of prenatally detected testicular teratomas have been reported in the English literature. An intra-abdominal mass and an ipsilateral undescended testis were confirmed after birth in all 6 cases. Preservation of testicular tissue was not performed in any case. Herein, we report the first case of prenatally diagnosed intrascrotal testicular teratoma in an infant who underwent testis sparing surgery.

The role of the Janus kinase family/signal transducer and activator of transcription signaling pathway in fibrotic renal disease.

Over the past several years, a number of cytokines and growth factors including transforming growth factor ß1, tumor necrosis factor α, and angiotensin II have been shown to play a crucial role in renal fibrosis. The Janus kinase family (JAK) and signal transducers and activators of transcription (STATs) constitute one of the primary signaling pathways that regulate cytokine expression, and the JAK/STAT signaling pathway has increasingly been implicated in the pathophysiology of renal disease. This review examines the role of the JAK/STAT signaling pathway in fibrotic renal disease. The JAK/STAT signaling pathway is activated in a variety of renal diseases and has been implicated in the pathophysiology of renal fibrosis. Experimental evidence suggests that inhibition of the JAK/STAT signaling pathway, in particular JAK2 and STAT3, may suppress renal fibrosis and protect renal function. However, it is incompletely understood which cells activate the JAK/STAT signaling pathway and which JAK/STAT signaling pathway is activated in each renal disease. Research regarding JAK/STAT signaling and its contribution to renal disease is still ongoing in humans. Future studies are required to elucidate the potential role of JAK/STAT signaling inhibition as a therapeutic strategy in the attenuation of renal fibrosis.

Bladder Cancer in a Long-term Survivor of the Prune Belly Syndrome.

Prune belly syndrome (PBS) is a rare but morbid complexity of congenital anomalies that consists of abdominal wall defect, bilateral cryptorchidism, and urinary tract dilation. With the recent advances in perinatal care, the life expectancy of patients with PBS has improved. Although renal and sexual outcomes are frequently discussed in the literature, little is known about urinary tract malignancies in adulthood. Herein, we present a case of advanced bladder cancer in a 38-year-old man with PBS. To the best of our knowledge, a malignant tumor arising in a nondefunctionalized or nonaugmented bladder in patients with PBS has not been reported previously.

Unilateral Fibrous Hyperplasia of the Labium Majus in Pre- and Early Pubertal Girls: A Report on 3 Cases.

BACKGROUND: In recent years, certain prepubertal cases of asymmetric enlargement of the labium majus came to be recognized as a physiological condition in response to hormonal stimulation. However, there exist only scattered case reports or a few case series on this entity, with different terminology. CASE: We present 3 cases of unilateral asymptomatic swelling of the labium majus in otherwise healthy pre- and early pubertal girls. Physical examination revealed painless, fluctuating, nontender bulging that was recognized for a few years on one side of the labium majus. Ultrasound and magnetic resonance imaging showed increased labial soft tissue without any masses. In all cases, surgical excision was performed for cosmetic request. Histopathological diagnosis was fibrous hyperplasia of the labium majus in all cases. Recurrence occurred in one of 3 cases a year after surgery. SUMMARY AND CONCLUSION: Due to the site- and age-specific non-neoplastic physiological condition, we recommend prepubertal unilateral fibrous hyperplasia of the labium majus (PUFHLM), as the terminology accurately reflects this entity. For the differential diagnosis of genital disorders in children, recognition of PUFHLM is important to avoid unnecessary biopsy or invasive procedures. Surgical excision for cosmetic reasons should not be considered because of the benign nature of this entity and a high recurrence rate in childhood and early adolescence.

Histological analysis of testes in patients with 5 alpha-reductase deficiency type 2: Comparison with cryptorchid testes in patients without endocrinological abnormalities and a review of the literature.

As evidenced by the intact histology of the testes during infancy, testicular differentiation during the prenatal period occurs normally in individuals with 5 alpha-reductase type 2 deficiency (5αRD); however, a majority of these individuals suffer from azoospermia or oligospermia during adulthood, indicating that impaired spermatogenesis occurs postnatally. Although the accompanying cryptorchidism may be partly responsible for this process, the underlying mechanisms remain largely unknown. To address this issue, we retrospectively compared the histological findings of descended testes in a 3-mo-old patient and undescended testes in an 18-yr-old patient with 5αRD. In the latter, testicular histology was compared to that of cryptorchid testes obtained from five adolescent patients without endocrinological abnormalities. Histological findings of a 3-mo-old patient revealed normal number of germ cells with intact seminiferous tubules. In contrast, an 18-yr-old patient showed marked reduction in germ cell number and atrophic seminiferous tubules. The findings were very similar to those observed in cryptorchid testes without endocrinological abnormalities. These findings suggest that the decrease in germ cells in 5αRD patients may be at least partly caused by accompanying cryptorchidism. As the number of germ cells did not decrease during the infantile period, early orchiopexy is recommended to prevent a decrease in germ cell number and preserve fertility.

[CLINICAL AND IMAGING FINDINGS OF ACUTE EPIDIDYMITIS IN CHILDREN].

(Objective) The etiology of acute epididymitis in children remains poorly understood. Several studies have demonstrated that urine tests are negative in the majority of children with acute epididymitis, and the condition is self-limiting. The need for radiological evaluation of the urinary tract in children with acute epididymitis is still debatable. The aim of this study was to describe clinical and imaging findings in children with acute epididymitis. (Methods) We identified 47 children with acute epididymitis at our institute between 2017 and 2021.We retrospectively reviewed their clinical features and radiological and laboratory data. All children underwent ultrasonography of the kidney and urinary tract. (Results) Median patient age was 9 years (range, 6 months-16 years) and 60% of the cases occurred between the ages of 7 and 12 years. Thirteen children (28%) had a past history of genitourinary malformations. The common malformations were hypospadias in eight children and bladder dysfunction in three. Ultrasound revealed no new urinary tract abnormalities in the remaining 34 children. Urinalysis were performed in 27 children, nine of whom (33%) had pyuria. Urine culture was positive in two children. Of the nine children with genitourinary malformations, eight had pyuria. All 18 children without genitourinary malformations had a negative urinalysis except for one patient (p< 0.0001). (Conclusions) Acute epididymitis is a common cause of acute scrotum in pediatric patients. In this study, one-third of acute epididymitis cases presented pyuria, and about 30% had a past history of genitourinary malformations. The presence of pyuria was associated with a past history of genitourinary malformations. For children with no previous genitourinary malformations, routine use of ultrasound for the detection of urinary tract abnormalities is questionable due to the low yield.

Successful separation of male pygopagus with anal canal and urethral reconstruction: a case report.

BACKGROUND: Pygopagus is a type of conjoined twin binding at the buttocks. Some cases of pygopagus involve the fusion of the gastrointestinal tract, urinary tract, and spinal cord. Few cases of male pygopagus have been reported; however, the prognosis after separation is unclear. Herein, we report a case of male pygopagus in which successful separation was performed with the reconstruction of the anal canal. CASE PRESENTATION: Twins with male pygopagus were born at 35 weeks by cesarean section. They shared a common anus, penis, and scrotum with four testes. The infants had normal defecation and urination after birth. The separation surgery was scheduled when they were 5 months. Two distinct anesthesia teams and four surgical teams (neurosurgery, pediatric urology, plastic surgery, and pediatric surgery) were involved in the multidisciplinary approach. After separating the spinal cord, we found that the anal canal and sphincter muscle complex were fused near the anal aperture, and we separated them. The fused penis and testis were separated and reconstructed using the same incisional line as the other separation, and the reconstructions of the anal canals with the sphincter muscle complex were completed. Both patients had an uneventful postoperative course. At 2 years of age, they could walk and defecate independently. In addition, they voided spontaneously without urinary incontinence at the time of 3 years and 11 months. CONCLUSIONS: Separation of the spinal cord with anal canal and urethral reconstruction is important for male pygopagus patients as it allows them to preserve their independent function.

Acquired undescended testes in boys with hypospadias.

PURPOSE: We determined the incidence of acquired undescended testes in boys with hypospadias. MATERIALS AND METHODS: We retrospectively reviewed the records of 566 boys with hypospadias who were referred to our outpatient clinic between January 2000 and September 2009. Acquired undescended testes were defined as testes that were documented at the bottom of the scrotum at least once after birth by the pediatric urologist at our institution but were subsequently documented to have moved from a satisfactory scrotal position by the same pediatric urologist or an equally experienced pediatric urologist. However, this definition did not include undescended testes after inguinoscrotal surgery. We excluded boys with gender development disorders with testicular dysgenesis, those who underwent bilateral inguinoscrotal surgery and those without congenital cryptorchidism who were followed less than 3 months. RESULTS: Of the 566 boys with hypospadias 100 met study exclusion criteria. Of the 466 boys included in analysis 29 (6.2%) had congenital cryptorchidism and 15 (3.2%) had acquired undescended testes. Urethroplasty was performed in 413 boys, including 91 with distal, 132 with mid and 181 with proximal hypospadias. The incidence of congenital cryptorchidism and acquired undescended testes in boys with proximal hypospadias was significantly higher than that in boys with other types of hypospadias (p = 0.03 and 0.001, respectively). CONCLUSIONS: Boys with proximal hypospadias are at a higher risk for acquired undescended testes than those with other mild types of hypospadias. Thus, testicular location should be monitored regularly until after puberty.