2309 Vasculitic Mononeuritis Multiplex Mimicking Bilateral Carpal Tunnel Syndrome: A Diagnostic Challenge

Abstract

INTRODUCTION: Cryoglobulinemic vasculitis(CV) can have variety of presentations including palpable purpura, arthralgias, glomerulonephritis, peripheral neuropathy, lymphadenopathy, hepatosplenomegaly, and hypocomplementemia. We present a patient with bilateral hand mononeuritis multiplex secondary to hepatitis C related CV. CASE DESCRIPTION/METHODS: A 52-year-old man with untreated hepatitis C (Viral load 520388, Genotype 1b), diabetes mellitus type II, hypertension and chronic kidney disease, presented with two months of bilateral hand pain. He also complained of numbness and tingling over the palmar aspects of the medial three digits of his hands, in addition to his medial left foot. He had no rash, arthritis, fevers, or weight loss. Physical exam was significant for positive Tinel's sign bilaterally, with weakness on finger extension, flexion and decreased power of interossei. Fundoscopy demonstrated non proliferative diabetic retinopathy (NPDR).Laboratory work-up revealed negative ANA, C-ANCA, MPO/PR3, HIV and RPR. Vitamin B12 and TSH levels were normal. However, serum cryoglobulins were positive with low C3, C4 and nephrotic range proteinuria Electromyography showed non-length-dependent neuropathy, which was more suggestive of mononeuritis multiplex rather than carpal tunnel syndrome (CTS). Sural nerve biopsy was performed and revealed vasculopathic changes consistent with vasculitis. He was diagnosed with mononeuritis multiplex secondary to hepatitis C related cryoglobulinemia. Immunosuppresive treatment was withheld because the patient tested positive for latent Tuberculosis (TB). He is currently undergoing treatment for the latent TB. DISCUSSION: CV is a small-to-medium-vessel vasculitis that occurs in 10 to 15 percent of patients chronically infected with hepatitis C virus (HCV). The two competing diagnosis for our patient’s neurological symptoms were diabetic neuropathy and CV secondary to untreated Hepatitis C. NPDR favored the microvascular complications of diabetes but the rapid onset of symptoms, positive cryoglobulins in the setting of HCV infection and sural nerve biopsy helped to establish the diagnosis of CV. This case is especially unique because it’s a very rare extrahepatic manifestation of HCV infection .Management of HCV cryoglobulinemic vasculitis involves administration of immunosuppressive therapy such as rituximab and antivirals but all patients should be tested and treated for latent TB prior to treatment initiation.