Keratinizing squamous metaplasia of the upper urinary tract in a child with a solitary kidney
A 3-year and 6-month-old male child presented to us with complaints of intermittent fever for 1 month. The parents complained of refusal for feeds and lethargy. He had a history of polydipsia and polyuria. Antenatal ultrasound scans had identified an absent right kidney with hydronephrosis of the left kidney. His parents had been advised surgery for left pelviureteric junction obstruction at the age of 2 months, but they had refused.\nAt presentation to us, the child had chronic renal failure with severe metabolic acidosis. A large renal lump was palpable in the left flank. Blood investigations revealed Hb of 6 gm%, total leukocyte count of 15,900/cumm, serum sodium of 116 mmol/L, serum potassium of 2.1 mmol/L, serum creatinine of 2.8 mg/dL and blood urea nitrogen of 97 mg/dL. Urine examination revealed pyuria with significant growth of Escherichia coli. Ultrasound of the kidney revealed absent right kidney with gross hydronephrosis and parenchymal thinning on the left side. Debris was noted in the dilated pelvicalyceal system.\nThe child was stabilized in pediatric intensive care for fluid and electrolyte imbalance and was administered culture specific antibiotics.\nThe DTPA scan revealed non-visualization of the right kidney with severely diminished parenchymal uptake on the left side without any excretion over 24 hours.\nAfter stabilization, he was taken for open left pyeloplasty. The kidney was grossly dilated with thinned-out parenchyma. The dilated pelvicalyceal system was full of an unusual, white creamy material with thin flakes, not resembling pus []. The system was also lined by the same material. The flakes were gently aspirated out and sent for culture and histopathology. Anderson-Hyne's dismembered pyeloplasty was performed with a nephrostomy tube. The post-operative course was uneventful. Hisopathology revealed focal areas of mature squamous epithelium with keratinization. The flakes were suggestive of an acellular keratin-forming membranous sheath [].\nAt a follow-up of 1 year, the child is asymptomatic with normal renal function.