[Salivary and lacrymal gland disorders and HTLV-1 infection]

The frequency and severity of salivary and lacrymal gland human T-cell lymphotropic virus type 1 (HTLV-1) infection were assessed in HTLV-1 plus patients, presenting with neurological deficit (tropical spastic paraparesis/HTLV-1 associated myelopathy [TSP/HAM]) or not. The mechanism of this deficit was investigated.

A case-control study was made from April 2002 to December 2005, in an area strongly endemic for HTLV-1. The patients were classified in three groups: group 1 with 16 patients presenting with TSP/HAM; group 2 with 67 HTLV-1 carriers and group 3 with 29 healthy volunteers. The dry syndrome was investigated by history taking and by oral and ophthalmological clinical examination. Immunological and biological screening for rhumatoid factors, antinuclear antibodies, and antibodies against soluble nuclear antigens (SSA, SSB). Peripheral blood was separated by density gradient and mononuclear cells were recovered to dose interferon-gamma and tumor necrosis factor-alpha. Patients in the three groups were assessed for salivary flow by stimulated weighing using Saxon's test. A Chi-2 test, a variance analysis (Anova), and the Spearman rank correlation test were used for the statistical analysis.

The dry syndrome was mild and more common in group 1 patients (75%). In group 2, 22% of the patients presented with functional signs of buccal mucosa dryness comparable to those observed in group 1. No correlation was found between salivary flow and screened pro-inflammatory cytokines.

Our results show that hyposialia is an important part of the disease induced by HTLV-1, even in virus carriers without neurological deficit. Its mechanism seems different than that of the Gougerot-Sjögren syndrome.