Polyclonal Antibody-Induced Serum Sickness Presenting as Rapidly Progressive Descending Paralysis

Abstract

Polyclonal antibody-induced serum sickness is an immune-complex mediated illness that is commonly manifested as fever, arthralgias, arthritis, lymphadenopathy, with or without renal failure. To our knowledge, an associated rapidly progressive descending paralysis has never been documented. We report a case of a living related renal transplant recipient who presented with serum sickness 1 week after the completion of a 7-day course of rabbit antithymocyte globulin (thymoglobulin at a dose of 1.5 mg/kg/day) for presumed severe acute cellular rejection due to inadvertent discontinuation of tacrolimus immunosuppression. As the patient was taking daily aspirin at the time, a biopsy was not performed. On exam, she was found to have a swollen and tender graft. Her serum creatinine peaked at 2.9 mg/dl and returned to her baseline at 1.3 mg/dl after thymoglobulin therapy. At one week after discharge, however, the patient presented with polyarticular arthralgias, myalgias, back pain, trismus, severe muscle weakness and descending paralysis that progressed within a matter of hours. She also developed a generalized pruritic skin rash that resolved with self-medicated diphenhydramine. On exam, she was noted to have severe joint tenderness at the knees, ankles, shoulders, wrists, and mandible. Neurological assessment revealed bilateral proximal greater than distal weakness, hyperreflexia, and ankle clonus. A clinical diagnosis of thymoglobulin-induced serum sickness was entertained although the neurological findings also raised the possibility of central nervous system pathology, and/or inflammatory myopathies. Chemistry panel revealed a slight increase in serum creatinine to 1.5 mg/dl. Due to her debilitating symptoms, therapeutic plasmapheresis (TPE) was initiated the day of admission pending further evaluation with brain magnetic resonance imaging, cervical spine, and appropriate serologic testing. The patient had immediate relief of her joint pain during plasmapheresis, and more interestingly, drastic improvement of her extremity weakness by the end of the session. She received a second course of plasmapheresis on hospital day 2 due to residual extremity “discomfort” and had complete resolution of her symptoms. Her serum creatinine decreased to 1.1 mg/dl. At 1 week follow-up, the patient reported doing well and had returned to her routine daily activities. The use of TPE in the treatment of serum sickness after antithymocyte globulin therapy has been well reported (1–3). Compared to pulse steroid or analgesics, TPE accelerates the time to recovery (10–14 days vs. 24–48 hr, respectively) (1–3). To our knowledge, this is the first case report of thymoglobulin-induced serum sickness presenting as descending paralysis. Phuong-Thu T. Pham Division of Nephrology, Kidney, and Pancreas Transplantation David Geffen School of Medicine at UCLA Los Angeles, CA Phuong-Mai Pham Department of Medicine Central Maine Medical Center Lewiston, ME Jeffrey M. Miller Division of Hematology/Oncology Olive View UCLA Medical Center Sylmar, CA Phuong-Chi T. Pham Division of Nephrology, Olive View UCLA Medical Center Sylmar, CA