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Background It is established that Vitamin D deficiency is common in patients with Rheumatoid Arthritis (RA)[1], and that the prevalence of chronic infection is increased in RA [2]. Vitamin D deficiency has been proposed as a factor in the increased propensity of RA patients to develop chronic infection. As bronchiectasis is particularly well described in association with RA, this model of chronic infection offers an excellent model to test our hypothesis. Objectives Our objectives were to test the concept that vitamin D deficiency is a factor in RA patients developing chronic infection. We did this by assessing the potential role of vitamin D deficiency in a cohort of patients with both RA and bronchiectasis. As anti cyclic citrullinated peptide antibodies (ACPA) are elevated in patients with active RA, we were also keen to assess any potential relationship between vitamin D levels and ACPA titres. Methods We identified all patients with prevalent diagnoses of RA (EULAR criteria 2010) and bronchiectasis (confirmed by high resolution computed tomography) using our centre database. We collected demographic details and measured Vitamin D and ACPA titres for both this group of patients, and for an age and gender matched control group of RA patients with no evidence of lung disease. We calculated the median age, gender ratio, median vitamin D levels and ACPA titres in both groups for comparison. We calculated the number of patients deficient in vitamin D, defined as a level below 30nmol/l. Results We identified 42 patients with both RA and bronchiectasis, and excluded 8 of these due to incomplete data. In the remaining 34 patients: 21 (62%) were female, giving a female to male ratio of 1.6 with a median (range) age of 70 (55-81) years. The median (range) vitamin D level for the group was 34.6 (9.5 -130) nmol/l and 15 patients (44%) were vitamin D deficient. The median (range) vitamin D level among RA controls was 39.4 (18 – 103) nmol/l and 40% of the controls were vitamin D deficient [NS]. In patients with RA and bronchiectasis, the median (range) titre of ACPA was 185.5 (1.5 - >340) and 6 (17%) had a negative ACPA test. Among the RA controls, the median (range) ACPA titre was 89 (0 – 340) and 40% patients were ACPA negative (P = 0.01). There was no significant correlation between levels of vitamin D and ACPA titres (r = 0.26). Conclusions Our results showed no significant reduction in vitamin D levels in patients with RA and bronchiectasis, although vitamin D deficiency was common in both groups as expected. There was no correlation between vitamin D levels and ACPA titres. Patients with RA and bronchiectasis had elevated ACPA titres when compared to RA controls and were more likely to be ACPA positive. Hence, although we have not shown vitamin D deficiency to be associated with chronic lung infection, increased ACPA titres suggest that such patients may have more active or severe RA. References Rossini et al, Vitamin D deficiency in rheumatoid arthritis: prevalence, determinants and associations with disease a...

Background Vitamin D levels have been reported as being low in a variety of rheumatological diseases and the possibility that patients who are vitamin D deficient might be at greater risk of developing immunological disease has been raised [1]. Indeed, some studies have suggested an inverse correlation between vitamin D and disease activity in rheumatoid arthritis (RA) [2]. Furthermore, patients with RA are known to have an increased incidence of both acute and chronic infections. Some of the factors contributing to this have been investigated but, to date, there are no data on the possible contribution of low vitamin D levels to this phenomenon. Objectives To assess the possible contribution of low vitamin D levels to the observed increased risk of infections in patients with RA Methods We identified 33 patients with RA and recurrent urinary tract infections (UTI), and a further 33 patients with bronchiectasis complicating RA. Patients with UTI had proven urinary pathogens cultured from mid stream urine. Those with bronchiectasis had confirmation of the diagnosis by high resolution computed tomography. We then identified an age and gender matched case control with RA, but no history of bacterial infection within 5 years, for each index patient. These controls were recruited randomly from consecutive out patients with RA. We then measured 1,25 dihydroxy vitamin D levels in all index cases and case controls in a two month period over the early winter using the same technique. Results were analysed and compared using Students t test after normal distribution of results was confirmed. Results Our index cases comprised 66 patients with a mean age of 67 (range 43-88 years). As expected, there were a preponderance of females with a female to male ratio of 3.8: 1. Case controls therefore mirrored these data. The mean vitamin D value in RA patients with UTI was 48.0 nmol (SE 7.8), while those with bronchiectasis had a mean vitamin D level of 50.9 nmol (SE 7.2). Among these 66 index RA patients with infection, 7% were vitamin D deficient (<20nmol), 50% were vitamin D insufficient (20-48 nmol) and 43% were vitamin D replete (>48 nmol). By comparison, the mean vitamin D level in the RA case controls was 55.0 nmol (SE 6.3), and 14% were vitamin D deficient, 33% insufficient and 53% replete. There were no significant differences in vitamin D levels between index cases and controls in any comparison. Conclusions Although persuasive data exist to support the observed increase in risk of infection in patients with RA, and mechanisms to reduce this trend have been suggested [3], the data presented here show no significant contribution of low vitamin D levels to this process. RA patients with acute or chronic infection appear no more likely than RA patients with no history of recent infection to have any evidence of vitamin D deficiency or insufficiency. References Marques CD, Dantas AT, Fragoso TS, Duarte AL. The importance of vitamin D levels in autoimmune diseases. Rev Bras Rheumatol. 2010; 50: 67-80 Rossini M. Vitamin D d...