Transforming growth factor-beta 2 heterozygous mutant mice exhibit Cowper's gland hyperplasia and cystic dilations of the gland ducts (Cowper's syringoceles)

Cowper's Syringocele: A Literature Review

Cowper's syringocele is a rare but underdiagnosed cystic dilatation of the main ducts of Cowper's gland. It is becoming more widely known in the adult population. Recent research proposes that syringoceles should be categorized according to the intraductal pressures causing ductal dilatation from mild to gross ultimately involving the gland itself. Although there may be some overlap in the clinical manifestations of different syringoceles, mildly dilated ducts are frequently asymptomatic. Moreover, moderate to gross duct dilatations can manifest as lower urinary tract symptoms (LUTS) or obstructive symptoms. A valid differential diagnosis is essential because these symptoms can be found in a wide range of severe illnesses. Syringocele can be diagnosed by ultrasonography in combination with voiding retrograde/antegrade cystourethrogram (VCUG), nevertheless, other procedures like cystourethroscopy, CT scan, and MRI scans can be helpful. Initially, conservative surveillance is advised, but if necessary, endoscopic marsupialization or surgical excision is the preferred treatment modality to address persistent problems.

Imaging of the Bulbourethral (Cowper) Gland: Abnormalities and Differential Diagnosis

Normal Cowper glands and ducts are imperceptible at imaging. However, abnormalities of the Cowper glands and ducts are increasingly seen owing to increasing use of cross-sectional imaging. In this article, the authors present a comprehensive review of the normal anatomy of the Cowper glands and ducts and the clinical and imaging findings of conditions that affect them in an effort to help lead to appropriate diagnosis and management. A Cowper duct syringocele is a congenital or acquired dilatation of the Cowper duct in the bulb of the corpus spongiosum. Retrograde urethrography is the standard test to diagnose a communicating (open) Cowper duct syringocele, and MRI is used for further morphologic assessment. Cowperitis refers to inflammation of the gland and/or duct, and recurrent cowperitis is usually associated with an underlying syringocele, a urethral fistulous connection to the Cowper gland, or a perianal fistula. MRI allows detection of the underlying structural abnormality and the superimposed inflammation. Cowper stones are typically radiopaque and are found in both the Cowper gland and duct. A Cowper gland HHhemorrhagic cyst may be incidentally detected at MRI of the prostate, and follow-up MRI may be required to ensure evolution of hemorrhage and exclude an underlying neoplasm. Cowper gland carcinoma is rare and includes adenocarcinoma and adenoid cystic carcinoma subtypes. Transperineal US may be used for initial evaluation and CT and/or MRI are necessary for further characterization and staging. Cowper gland hyperplasia is a rare entity with few previous reports that may be incidentally detected at imaging and may mimic malignancy. ^©RSNA, 2022.

Cowper's Syringocele: A Rare Cause of New-Onset Voiding Dysfunction

Cowper's syringocele is a condition caused by dilatation of the main duct of Cowper's gland. It is a very uncommon cause of urethral obstruction. Closed type causes urinary obstruction. The aim of this article is to report a case of closed type syringocele causing new-onset urinary obstruction in a 10-year-old boy.

Syringoceles of Cowper's ducts and glands in adult men

Cowper's syringoceles are uncommon, usually described in children and most commonly limited to the ducts. We describe more complex variants in an adult population affecting with varying degrees of severity, the glands themselves, and the complications they may lead to. One hundred consecutive urethrograms of patients with unreconstructed strictures were reviewed. Twenty-six patients (mean age: 41.1 years) with Cowper's syringoceles who were managed between 2009 and 2016 were subsequently evaluated. Presentation, radiological appearance, treatment (when indicated), and outcomes were assessed. Of 100 urethrograms in patients with strictures, 33.0% demonstrated filling of Cowper's ducts or glands, occurring predominantly in patients with bulbar strictures. Only 1 of 26 patients with non-bulbar strictures had a visible duct/gland. Of 26 symptomatic patients, 15 presented with poor flow. In four patients, a grossly dilated Cowper's duct obstructed the urethra. In the remaining 11 patients, a bulbar stricture caused the symptoms and the syringocele was identified incidentally. Eight patients presented with perineal pain. In six of them, fluoroscopy and magnetic resonance imaging (MRI) revealed complex multicystic lesions within the bulbourethral glands. Four patients developed perineoscrotal abscesses. In the 11 patients with strictures, the syringocele was no longer visible after urethroplasty. In three of four patients with urethral obstruction secondary to a dilated Cowper's duct, this resolved after transperineal excision (n = 2) and endoscopic deroofing (n = 1). Five of six patients with complex syringoceles involving Cowper's glands were excised surgically with symptomatic relief in all. In conclusion, Cowper's syringocele in adults is more common than previously thought and may cause lower urinary tract symptoms or be associated with serious complications which usually require surgical treatment.

Histology, ultrastructure, and seasonal variations in the bulbourethral gland of the African straw-colored fruit bat Eidolon helvum

We studied the morphological characteristics and seasonal changes of the bulbourethral gland of Eidolon helvum in a typical African tropical environment. Forty-eight bulbourethral glands were examined using gross anatomical, histological, histochemical, and ultrastructural techniques during the early rainy, late rainy, and peak dry seasons. The pear-shaped bilateral bulbourethral glands were located extra-abdominally in the inguinal region. Trabeculae from the capsule divided the parenchyma into numerous lobules of tubuloalveolar glandular acini. The mucosa was covered by a simple columnar epithelium consisting up of principal secretory cells, columnar dense cells and basal cells, which were progressively pronounced during the dry season. The principal cells contained eosinophilic granules, which were PAS positive while the dense cells did not show affinity for the stains. The mean gross weights, acini diameters, and epithelial heights were greater during the rainy season than the dry season. Ultrastructural evaluation showed that the cytoplasm of the principal cells contained well-developed Golgi complexes, rough endoplasmic reticulum, mitochondria, and secretory vesicles of varying electron densities and sizes. The secretory vesicles were numerous during the early rainy season, decreased during the late rainy season and were scanty during the peak dry season. The simple columnar epithelium observed during the rainy season was replaced by an undefined stratified epithelium during the dry season, and this was associated with cellular degenerations and regenerations. In conclusion, E. helvum has a typical mammalian bulbourethral gland, with a unique cell type, the dense cell whose functions are not well-understood. The gland exhibits cyclical seasonal variation in structure and secretory activity; being active during the early rainy season (breeding season), and showing the lowest activity during the dry season (non-breeding season). Glandular epithelial cell renewal occurs during the dry season in preparation for the next breeding season.

Cowper's syringocele in the pediatric population: a retrospective study of 122 patients

INTRODUCTION AND OBJECTIVE

Syringocele is a rare cystic dilatation of the duct of Cowper's gland, afflicting mostly the pediatric population. Syringoceles have a wide range of symptoms and may cause urethral obstruction. The authors analyzed to clarify the clinical manifestation, diagnostic approach, management, and incidence in the pediatric population.

MATERIALS AND METHODS

All patients (122 cases) diagnosed with a syringocele at the department of Pediatric Urology in a tertiary referral university children's hospital between August 1991 and October 2016 were analyzed retrospectively by assessing medical charts.

RESULTS

The clinical manifestation, diagnostic findings, and follow-up are summarized in the table. Half of the patients (50.0%) also had typical posterior urethral valves (PUVs) and/or a single valve in the 12 o'clock position (flap-valve). The symptoms of open and closed syringoceles showed no significant difference. Treatment consisted of incision of the syringocele with a diathermia hook. The incidence of urinary tract infection (UTI) before and after surgery in the group that had a syringocele only was significant different. The overall incidence of syringoceles seen at urethrocystoscopy in this series was 3.0%.

DISCUSSION

This series suggests that the presenting age is strongly related to the consequences of syringoceles, as the youngest half of the patients had significantly more UTIs at presentation than older patients, who presented with significantly more obstructive voiding symptoms, postvoiding residuals, and incontinence. In addition, the younger group had a significantly higher incidence of vesicoureteral reflux and dilatation of the upper urinary tract. The found association between syringoceles and PUV may be due to overgrowth of epithelium, as possible origin in both anomalies.

CONCLUSION

With an incidence of 3.0%, syringoceles, in this tertiary referral series, should be considered in the differential diagnosis of obstructive urethral lesions. The presentation ranges between signs of severe obstructions in the prenatal and postnatal period to mild urinary incontinence problems at later age. Urethrocystoscopy proved to be useful in confirming the diagnosis and allows for immediate transurethral incision.

Proliferative and nonproliferative lesions of the rat and mouse male reproductive system

The INHAND Project (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature and differential diagnosis for classifying microscopic lesions observed in the male reproductive system of laboratory rats and mice, with color microphotographs illustrating examples of some lesions. The standardized nomenclature presented in this document is also available for society members electronically on the Internet (http://goreni.org). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and aging lesions as well as lesions induced by exposure to test materials. A widely accepted and utilized international harmonization of nomenclature for lesions of the male reproductive system in laboratory animals will decrease confusion among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.

Epithelial Bmp (Bone morphogenetic protein) signaling for bulbourethral gland development: a mouse model for congenital cystic dilation

The bulbourethral gland (BUG) is a male-specific organ, which secretes part of the semen fluid. As the BUG is located in the deep pelvic floor, its developmental process is still unclear. Bone morphogenetic protein (Bmp) signaling plays pivotal roles in various organs. However, the function of Bmp signaling for BUG development is still unclear. The present study aimed to elucidate the role of Bmp signaling in the development of the BUG. We observed the prominent nuclear accumulation of phosphorylated (p) SMAD1/5/8, the downstream molecules of Bmp signaling, during BUG epithelial development. These results suggest that Bmp signaling contributes to BUG development. Bmp receptor1a (Bmpr1a) is known as the major type 1 signal transducer in some organogeneses. To analyze the Bmp signaling function for BUG development, we examined epithelial cell-specific Bmpr1a gene conditional mutant mice utilizing the tamoxifen-inducible Cre recombinase system. We observed cystic dilation and epithelial hyperplasia of the BUG in the Bmpr1a conditional knockout mice. The mutant cystic BUG specimens also showed inflammatory lesions. These BUG abnormalities resembled some of the BUG malformations observed in human congenital syndromes. The current study suggests that Bmp signaling possesses an essential role in BUG development and homeostasis. This would be the first report showing that the mutation of the Bmpr1a gene in the BUG epithelia phenocopied some abnormalities of human congenital syndromes affecting the BUG duct.

A neglected gland: a review of Cowper's gland

Cowper's glands are pea sized glands present inferior to the prostate gland in the male reproductive system. They produce thick clear mucus prior to ejaculation that drains into the spongy urethra. Though it is well established that the function of the Cowper's gland secretions is to neutralize traces of acidic urine in the urethra, knowledge regarding the various lesions and associated complications of this gland is scarce. This review provides a comprehensive report on the development, function and various lesions associated with Cowper's gland.

Transport of transforming growth factor-β2 across the blood–brain barrier

The blood-brain barrier acts as an interface between the brain and body through a combination of restrictive mechanisms and transport processes. Substances essential for brain function pass through the barrier either by passive diffusion or by active transport. We report here that [125I]-transforming growth factor-beta2 (TGF-beta2) passes through the blood-brain barrier and blood-nerve barriers, after intravenous, intraperitoneal or intramuscular injections. The entry of the [125I]-TGF-beta2 to the brain was rapid, saturable and inhibited by co-injection of unlabelled TGF-beta2. In contrast, co-injection of unlabelled TGF-beta2 increased the retention of [125I]-TGF-beta2 in the blood. The [125I]-TGF-beta2 transported into the brain was localised by autoradiography to the extracellular space, and was intact as judged by SDS-PAGE. The [125I]-TGF-beta2 was widely distributed throughout the brain, with the highest concentrations in the hypothalamus and nerves and the lowest in the cerebral hemispheres. The [125I]-TGF-beta2 had a half-life of 4 h in the brain. These results indicate that therapeutically relevant levels of TGF-beta2 reach the brain after peripheral administration of TGF-beta2.

Anterior urethral valves and diverticula in children: a result of ruptured Cowper's duct cyst?

OBJECTIVE

To review a series of children with anterior urethral valves and diverticula, to elucidate the pathophysiology and optimal management of this entity.

PATIENTS AND METHODS

Nine cases (all boys; 1963 to 2003) were reviewed retrospectively.

RESULTS

Seven of nine boys had bulbar diverticula. Continuity between Cowper's duct and the diverticulum was noted endoscopically in two and confirmed radiographically in one. Initially, open surgery was curative but more recently endoscopic management has been the procedure of choice.

CONCLUSION

This series indicates that the distal lip of a ruptured syringocele may function as a flap-valve, leading to anterior urethral obstruction. Advances in imaging and endoscopic instruments have altered the mode of presentation and management of this entity.