Natural killer cell lymphoproliferative disease associated with combined peripheral and autonomic neuropathy

Natural killer cell proliferation is an uncommon haematological disorder that has a number of different clinical manifestations. There have been only two prior reports linking this process with neurological disease, both reports describing peripheral neuropathy. We report the case of a young man presenting with a short history of lethargy, lower limb paraesthesia and marked weight loss who was found to have a natural killer cell lymphocytosis and features of both an autonomic and a peripheral neuropathy. The patient's clinical features responsed to a combination of cytotoxic and immunosuppressive therapy, and the patient is now clinically stable with mild ongoing lymphocytosis, diarrhoea and postural hypotension. We review the possible pathological link between natural killer cells and neurological disease.