Peripheral neuropathy associated with sicca complex.

Peripheral neuropathy occurs in Sjögren's syndrome, a disorder in which systemic immunologic phenomena, including vasculitis, are common. Neuropathy also occurs with isolated sicca complex (keratoconjunctivits sicca and xerostomia); whether this represents a distinct syndrome is unclear. We retrospectively studied 54 patients with sicca complex and peripheral neuropathy to determine mode of presentation, neuropathic patterns, frequency and pattern of serologic abnormalities, and frequency of systemic disease, including necrotizing vasculitis. Peripheral neuropathy was the presenting problem in 87%. Although sicca symptoms occurred in 93%, they were a presenting complaint in only 11% and were usually mild, reported only after specific inquiry. Minor salivary gland biopsy was positive in 73%. Sensory neuropathies strongly predominated; 61% of patients manifested either sensory polyneuropathy or polyganglionopathy. Less common patterns included sensorimotor polyneuropathy (17%) and polyradiculoneuropathy (11%). Vasculitic neuropathy was demonstrated in only two patients, but nonspecific epineurial inflammation was present in 70% of nerve biopsies. Clinical evidence of systemic disease was uncommon, particularly in the sensory polyganglionopathy group, in whom extraglandular features other than weight loss occurred in only 1 of 12 patients. Antibodies to extractable nuclear antigens, the most specific serologic marker of Sjögren's syndrome, were present in 10.4%. We conclude that peripheral neuropathy and isolated sicca complex form a distinctive syndrome in which neuropathy is the presenting feature and sicca is easily overlooked; sensory polyneuropathy and polyganglionopathy predominate; serology is confirmatory but very insensitive; and extraglandular disease, including vasculitis, is uncommon compared with typical Sjögren's syndrome. Tests of ocular or salivary involvement are needed for diagnosis, and demonstration of inflammation in biopsied nerve is supportive. Improved definition of this disorder should permit further studies of natural history and efficacy of immunotherapy.