An association of fibromyalgia with primary Sjögren's syndrome: a prospective study of 72 patients.

OBJECTIVE: Fibromyalgia patients often describe the presence of dry eyes and dry mouth. Conversely there is an increasing recognition that many patients with Sjögren's syndrome (SS) have fibromyalgia (FM). We decided to investigate this association.
METHODS: Seventy-two patients with FM were screened with a Schirmer's test. All patients with an abnormal test had a minor salivary gland biopsy.
RESULTS: Thirty-eight percent (n = 28) had a Schirmer's test of < 15 mm wetting at 5 minutes, however sicca symptoms were noted in only 19% of patients. Salivary gland biopsy in these 28 patients showed a focus score of > or = 1 in 5; a positive antinuclear antibody test (ANA) was found in 4, a positive rheumatoid factor in 3 and anti-SSA SSB antibodies in 2. Another 8 patients had abnormal salivary gland lymphocytic foci, but there were < 50 cells or the density was < 1 focus/4 mm2; all 8 of these patients had a positive ANA. None of these patients have developed systemic features of SS over a 6 year period of followup.
CONCLUSION: There is a subgroup of patients presenting with FM who, on further testing, have findings consistent with primary SS. The prevalence of this association was 6.9% for probable SS and 11% for possible SS. These figures are probably an overestimation due to tertiary center referral bias. The etiologic and management implications of these observations are unclear.