Abstract: PO2313
A Rare Pediatric Case of Karyomegalic Tubulointerstitial Nephritis
Session Information
- Pediatric Nephrology: Benign Urology, AKI, Neonatal Nephrology, and Case Reports
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1700 Pediatric Nephrology
Authors
- Becerril romero, Carlos Cesar, Indiana University School of Medicine, Indianapolis, Indiana, United States
- Kapil, Sasha R., Indiana University School of Medicine, Indianapolis, Indiana, United States
- Rahrig, April, Indiana University School of Medicine, Indianapolis, Indiana, United States
- Phillips, Carrie L., Indiana University School of Medicine, Indianapolis, Indiana, United States
- Hains, David S., Indiana University School of Medicine, Indianapolis, Indiana, United States
- Skiles, Jodi L., Indiana University School of Medicine, Indianapolis, Indiana, United States
- Gupta, Sushil, Indiana University School of Medicine, Indianapolis, Indiana, United States
Introduction
Karyomegalic tubulointerstitial nephritis (KIN) is a rare type of interstitial nephritis that often progresses to chronic kidney disease. The pathogenesis is unclear but speculated to result from disruptions to tubular epithelial cell division by genetic predisposition or external insults. Only 6 pediatric cases have been reported and perhaps this condition is underdiagnosed.
Case Description
A 2-year-old male with history of refractory AML received a matched unrelated donor stem-cell transplant following busulfan, fludarabine, and single fraction total body irradiation. His post-transplant course was complicated by engraftment syndrome, hyperacute graft versus host disease (GVHD), thrombotic microangiopathy, and acute kidney injury. He required ICU stay, treatment with eculizumab and two weeks of renal replacement therapy. His kidney function improved but serum creatinine stayed higher than baseline (picture). Four months post-transplant, he was treated with cefepime, acyclovir, ibuprofen for enterococcus bacteremia and pericardial effusion. Seven months post-transplant, while off all immunosuppression, he developed eosinophilia, renal tubular dysfunction with increased serum creatinine. Eosinophilia resolved spontaneously. Bone marrow was negative for leukemia and infectious workup was negative. Eight months post-transplant, he developed GVHD, diagnosed with skin biopsy. He also had persistent high serum creatinine with normal urinalysis. Ultrasound showed echogenic kidneys. Kidney biopsy was performed because of unexplained high serum creatinine. Specimen tissue showed tubulointerstitial nephritis with widespread karyomegaly in medullary tubules. Glomeruli were unaffected. Some cortical tubules showed ultrastructural myelinosomes. His renal function improved with steroids.
Discussion
Our case highlights that KIN can develop in children after chemotherapy. Diagnosis requires high index of suspicion and thorough pathological examination of kidney biopsy specimen. A trial of corticosteroid therapy may be considered.