The aims of the study were (a) to investigate the prevalence of Sjögren's-like syndrome (SLS) in an unselected population of HIV-1-positive patients and (b) to describe the pathology and immunopathology of the labial minor salivary gland biopsy. Seventy-seven HIV-1-positive patients were asked to answer the validated questionnaire of the European preliminary criteria for the classification of Sjögren's syndrome on oral and ocular sicca symptoms. Twenty-six patients gave one positive answer to both ocular and oral symptoms, and of these 14 (hepatitis C virus negative) consented to participate in the study (patients group). Ten age- and sex-matched HIV-1-positive patients with a negative questionnaire constituted the control group. Patients and controls had: (a) Schirmer's test and slit-lamp examination after Rose Bengal staining; (b) parotid gland scanning with technetium; (c) detection of autoantibodies in sera to Ro/SSA and La/SSB; (d) labial salivary gland biopsy (patients group only). The control group gave negative parotid gland scanning and only one gave a positive Rose Bengal staining test. In the patients group, parotid gland enlargement was manifested by three patients and only one gave positive Rose Bengal staining test. Six out of the 14 patients had biopsies identical with Sjögren's syndrome and five of these gave positive parotid gland scanning. In the biopsies of four other patients, mucoid degeneration of the stroma was found. Immunopathology revealed that the predominant cells were T cells with the CD8 phenotype. None of the patient and control sera had autoantibodies to Ro/SSA and La/SSB, whereas all patients had hypergammaglobulinaemia. The overall prevalence of possible SLS in a mixed population of HIV(+) patients (88.3% men and 11.7% women) was 7.79% which is >2.5 times higher than that observed in normal Greek adult females.