Castleman's disease (CD), a rare lymphoproliferative disorder, is characterized by histological features of lymph node hyperplasia and capillary proliferation. Conditions such as minimal-change, membranous, mesangioproliferative, membranoproliferative glomerulonephritis, thrombotic microangiopathy and renal amyloid have been reported with CD [1]. Acute renal failure (ARF) due to tumour-lysis syndrome (TLS) has not been reported in these patients.
Case. A 34-year-old Caucasian male was admitted to the Houston VA medical center with nausea, right upper quadrant and epigastric pain. His past medical history was significant for the diagnosis of HIV infection 11 years previously. He had refused therapy until 6 months prior to this admission when he developed constitutional symptoms and cervical lymphadenopathy. Lamivudine, Didanosine and Nevirapine were started since he had a low CD4 count (105 cells/l3) and a high viral load (>75 000 HIV RNA copies/ml). An abdominal CT scan at that time revealed extensive lymphadenopathy. The diagnosis of a plasma-cell variant of multicentric CD was made from a cervical lymph node excision biopsy.
During this admission, initial blood tests were as follows: serum creatinine 5.4 mg/dl, uric acid 12.9 mg/dl, phosphorus 3.1 mg/dl and serum LDH 361 U/l. Acute pancreatitis was also noted. Baseline serum creatinine and uric acid were not elevated. Renal ultrasound showed normal renal sizes with no evidence of hydronephrosis. Microscopic urinalysis showed granular casts without crystals or pyuria. Given this constellation of lab findings, the possibility of spontaneous TLS from CD was included in our differential diagnosis of ARF.
Introduction of cyclophosphamide and prednisone resulted in rapid destruction of tumour cells and worsening of TLS, manifested by a dramatic rise in the serum levels of creatinine, phosphorus (12 mg/dl), uric acid (20 mg/dl) and LDH enzyme (550 U/l). Cervical lymphadenopathy and pancreatitis improved. Haemodialysis was continued for 10 days along with allopurinol. With the resolution of TLS, renal function slowly improved over 6 weeks.
Comment. CD has hyaline-vascular and plasma cell variants and clinically could be localized or multicentric. While localized CD is a benign lymphoproliferative disorder, the multicentric type is associated with infections, multi-organ failure and malignancies [2]. It is postulated that Karposi's sarcoma associated virus (HHV-8) could play a crucial role in producing IL-6 and releasing angiogenic factors resulting in lymphoplasmacytic proliferation [2]. Renal involvement in CD has clinical presentations that vary from nephrotic syndrome to antimyeloperoxidase-antibody-positive rapidly progressive glomerulonephritis [3] and end-stage renal disease from renal amyloidosis [4].
Even though TLS is common in haematologic malignancies after chemotherapy, in rapidly growing tumours hyperuricaemia could be seen even without the introduction of chemotherapy or radiotherapy, an entity recognized as spontaneous TLS. We postulate that our patient initially may have had spontaneous TLS and that subsequent renal recovery was hampered by chemotherapy-induced TLS.
Conflict of interest statement. None declared.
Address MED Veterans Affairs Medical Center and Baylor College of Medicine, Nephrology, Houston, TEXAS, USA Email: ramanath{at}bcm.tmc.edu
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