Anti-Hu antibody neuropathy: a clinical, electrophysiological, and pathological study

Objective The objective is to report the clinical, electrophysiological, and histopathological features of 16 patients with anti-Hu antibody neuropathy. Methods Clinical and electrophysiological data in 16 patients (11 females and 5 males) with positive anti-Hu antibody and nerve biopsy data in 9 cases were analyzed. Results Cancer was detected in 11 patients, including 9 with small-cell lung cancer. Classical paraneoplastic subacute sensory neuronopathy (SSN) and/or encephalomyelitis (EM) was observed in 7 patients (44%), including 5 with SSN. The most common clinical feature was sensory-motor neuropathy (SMN), accounting for 50% of cases. Though sensory nerve conduction abnormality was the prominent feature in 14 (88%) cases, sensory and motor nerve conduction was abnormal in all cases. Motor nerve conduction findings were typical of axonal degeneration. The most common nerve conduction pattern was that of SMN, with a sensory neuronopathy pattern being observed in only 3 cases. Sural nerve biopsy in 9 patients showed axonal degeneration in all cases and inflammatory cells in 4 cases. Conclusions Classical sensory neuronopathy is rarer than expected, both clinically and electrophysiologically. Motor involvement is not uncommon and motor nerve conduction abnormality is frequently seen. A diverse clinical and electrophysiological, and histopathological spectrum was observed in this neuropathy. Significance New guidelines for the selection of patients for anti-Hu antibody test are recommended.