Congenital Unilateral Renal Aplasia in a Cynomolgus Monkey (Macaca fascicularis) With Investigation Into Potential Pathogenesis

We describe and characterize unilateral renal aplasia in a cynomolgus monkey ( Macaca fascicularis) from a chronic toxicology study adding to the limited histopathology reports of congenital renal anomalies in macaques. In the current case, the affected kidney was macroscopically small and characterized microscopically by a thin cortex with an underdeveloped medulla and an absent papilla. The remnant medulla lacked a corticomedullary junction and contained only a few irregular collecting duct-like structures. The cortex had extensive interstitial mature collagen deposition with fibromuscular collar formation around Bowman’s capsules. Due to parenchymal collapse, mature glomeruli were condensed together with occasional atrophic and sclerotic glomeruli. The majority of the cortical tubules were poorly differentiated with only small islands of fully developed cortical tubules present. Histochemical and immunohistochemical stains were utilized to demonstrate key diagnostic features of this congenital defect, to assist with differentiating it from renal dysplasia, and to provide potential mechanistic pathways. Immunostaining (S100, paired box gene 2 [PAX2], aquaporins) of the medulla was compatible with incomplete maturation associated with aplasia, while the immunostaining profile for the cortex (vimentin, calbindin, PAX2-positive cortical tubules, and smooth muscle actin–positive fibromuscular collars) was most compatible with dedifferentiation secondary to degenerative changes.

Neoureterocystostomy for the management of extramural ectopic ureter with concurrent contralateral renal aplasia in two dogs

Two male puppies were presented: one with urinary incontinence and the other with abdominal distension and discomfort. A diagnosis of unilateral extramural ectopic ureter with associated hydronephrosis/hydroureter and contralateral renal aplasia was confirmed in both patients by a combination of abdominal imaging and exploratory coeliotomy. Both patients were also diagnosed with cryptorchidism ipsilateral to the renal aplasia. Routine investigations, including complete blood count, biochemistry and urinalysis, were otherwise unremarkable. Neoureterocystostomy with an intravesical technique and castration were performed in both patients. One month following surgery, severity of clinical signs, the degree of hydronephrosis/hydroureter and elevation of renal blood values had all improved in both patients.

Pulmonary Sequestration with Renal Aplasia and Elevated SUV Level in PET/CT

Extralobar sequestration with other bronchopulmonary malformations is commonly seen; however, the association of extralobar sequestration with renal aplasia is very rare. A 75-year-old female patient was admitted with back pain. Ultrasonography revealed aplasia of the left kidney and tomography showed6×4.5 cm sized tumor in the left hemithorax at the posterobasal area. The lesion has focally increased glycolytic activity (SUVmax: 3.2) at the left upper pole on positron emission tomography scan (PET/CT). Sequestrectomy was performed after the confirmation by frozen section that the lesion was benign and of extrapulmonary sequestration. No complication occurred during postoperative and 50-month follow-up period.

48XXYY Syndrome in an Adult with Type 2 Diabetes Mellitus, Unilateral Renal Aplasia, and Pigmentary Retinitis

A 45-year-old male was referred for diabetes mellitus. Clinical examination found a family history of multiple precocious deaths, strong consanguinity, personal history of seizures during childhood, small testicles, small penis, sparse body hair, long arms and legs, dysmorphic features, mental retardation, dysarthria, tremor, and mild gait ataxia. Investigations found pigmentary retinitis, metabolic syndrome, unilateral renal aplasia, and hypergonadotropic hypogonadism, and ruled out mitochondrial cytopathy and leucodystrophy. Karyotype study showed a 48XXYY chromosomal type. Renal aplasia and pigmentary retinitis have not been described in 48XXYY patients. They may be related to the chromosomal sex aneuploidy, or caused by other genetic aberrations in light of the high consanguinity rate in the patient's family.