ABSTRACT Background Papillary cystadenoma is a rare benign neoplasm of the epididymis. It may occur sporadically or in association with von Hippel-Lindau disease (VHLD). Papillary cystadenoma of the epididymis (PCE) is a benign mimic of metastatic clear cell renal cell carcinoma (CCRCC) given their histologic similarities. Case presentation Herein, we present the case of a 40-year-old man with a four-year history of microhematuria and a recently detected right paratesticular mass. A testicular sonogram revealed a hypoechoic, hypervascular solid mass in the right epididymal head treated by surgical excision. Histopathological examination demonstrated a 1.1 cm papillary cystadenoma of the epididymis. Genetic testing performed later showed no signs of VHLD. However, heterozygous mutations in three genes - CASR, POT1, and RAD51D - were found which have never been reported in PCE before. Conclusions Papillary cystadenoma of the epididymis should always be considered in the differential diagnosis of epididymal lesions, especially those that are cystic. The mainstay of treatment remains surgical excision, which provides an excellent prognosis.

ABSTRACT Background Acute tubulointerstitial nephritis (ATIN) is a very rare paraneoplastic manifestation in patients with multiple myeloma (MM). It is an uncommon pattern of renal disease in such patients. Case presentation We report a case of an 82-year-old male who was admitted with acute kidney injury. Renal biopsy showed typical findings of light chain-associated ATIN with scattered inflammatory cells in the interstitium and associated active tubulitis. No other common manifestations of MM were present at the time of presentation, including hypercalcemia, hyperuricemia, proteinuria, bone pain or lytic bone lesions. Subsequent immunoassays revealed significant serum lambda light chain burden and Bence Jones protein in urine. Immunofluorescence demonstrated linear tubular basement membranes with positive staining for lambda light chain (3+). Electron microscopy (EM) further showed interstitial edema and inflammation. All the aforementioned findings are consistent with ATIN and supported the diagnosis of MM. Conclusions In conclusion, light chain-associated ATIN should be considered in the differential diagnosis of acute interstitial nephritis. Henceforth, serum free light chains as well as serum and urine protein electrophoresis should be included in the workup of such patients.

ABSTRACT Background Intestinal duplications are rare congenital developmental anomalies with an incidence of 0.005-0.025% of births. They are usually identified before 2 years of age and commonly affect the foregut or mid-/hindgut. However, it is very uncommon for these anomalies, to arise in the colon or present during adulthood. Case presentation Herein, we present a case of a 28-year-old woman with a long-standing history of constipation, tenesmus, and rectal prolapse. Colonoscopy results were normal. An abdominal computed tomography (CT) revealed a diffusely mildly dilated redundant colon, which was prominently stool-filled. The gastrografin enema showed ahaustral mucosal appearance of the sigmoid and descending colon with findings suggestive of tricompartmental pelvic floor prolapse, moderate-size anterior rectocele, and grade 2 sigmoidocele. A laparoscopic exploration was performed, revealing a tubular duplicated colon at the sigmoid level. A sigmoid resection rectopexy was performed. Pathologic examination supported the diagnosis. At 1-month follow-up, the patient was doing well without constipation or rectal prolapse. Conclusions Tubular colonic duplications are very rare in adults but should be considered in the differential diagnosis of chronic constipation refractory to medical therapy. Due to the non-specific manifestations of this entity, it is rather challenging to make an accurate diagnosis pre-operatively. Surgery remains the mainstay of treatment. Some reports suggest that carcinomas are more prone to develop in colonic/rectal duplications than in other GI tract duplications.

ABSTRACT Background Neonatal acute liver failure (NALF) is a rare and life-threatening condition. It causes bilirubin to accumulate to a dangerous level in the body, causing permanent damage to vital organs such as the brain and lungs. In many cases, the etiology of NALF remains unknown. Case presentation We described a case of an 8-day-old baby girl who presented with poor oral intake, lethargy, and jaundice. Her clinical condition rapidly deteriorated with progression to multi-organ failure, and despite intensive resuscitation efforts, she expired. At autopsy, the most significant findings were liver necrosis, yellow hyaline membrane deposition in the lungs, and bilirubin deposition in the brain (kernicterus). Conclusions NALF is a rare and potentially fatal condition necessitating prompt recognition and disease-specific treatment approaches. Toxic accumulation of bilirubin in the lungs can lead to hypoxia and precipitate further ischemic injury to the liver.

ABSTRACT Background The bowel is the most common site of extragenital endometriosis, with involvement of the locoregional sigmoid colon and anterior rectum seen most often. The clinical presentation varies depending on how soon patients seek medical care, thus requiring changes in management strategies. Endometriosis can cause a life-threatening surgical emergency with progressive obliteration of the bowel lumen leading to obstruction and late complications including toxic megacolon and transmural necrosis. Case presentation We report the case of a 41-year-old woman presenting with an acute abdomen and complete large bowel obstruction complicated by sepsis and toxic megacolon. The patient underwent emergency total colectomy with ileostomy. Medical history was significant for chronic, vague, and episodic lower abdominal pain self-medicated with herbal tea and laxatives. Pathologic examination demonstrated colonic endometriosis within the bowel wall as the cause of obstruction, ischemia, and transmural necrosis. Conclusions Although a rare clinical entity, this case highlights two important points. First, it demonstrates the value of performing proper and complete clinical work up to rule out or in all possible causes of colonic obstruction, including intestinal endometriosis. Second, it suggests a potential benefit of a formalized multidisciplinary approach, including surgery, in the management of medically unresponsive endometriosis. In conclusion, this case shows that endometriosis can cause life-threatening colonic obstruction in women of childbearing age. Prompt early intervention is warranted, particularly when obstruction is only partial and ischemia has not supervened, to conceivably prevent the development of a toxic megacolon requiring colectomy and avoid late complications.

ABSTRACT Background Hemangiomas are benign neoplasms of capillary proliferation that arise from a developmental anomaly where angioblastic mesenchyme fails to form canals. Most hemangiomas arise in the head and neck region, either superficially in the skin or deeper within endocrine organs such as the parotid gland. Parathyroid hemangiomas, however, are extremely rare, with only five cases previously reported in the literature. Case presentation Herein, we present a case of a 68-year-old man with a hemangioma almost completely replacing the right upper parathyroid gland, grossly measuring 1.3 × 1.3 × 1.2 cm and weighing 700 mg, associated with primary hyperparathyroidism. Conclusions Parathyroid gland enlargement due to vascular neoplasms such as hemangiomas can mimic, both clinically and radiographically, hyperplasias and/or adenomas. Surgeons need to be aware of the presence of this entity and should consider it in the differential diagnosis of hyperparathyroidism or parathyroid gland enlargement.