Opportunistic infections in polymyositis and dermatomyositis

Abstract
Objective To assess prevalence and characteristics of opportunistic infections in patients with polymyositis/dermatomyositis (PM/DM). To determine the predictive values for opportunistic infections on clinical presentation, biochemical findings, and paraclinical features of PM/DM to detect patients at risk of opportunistic infections. Methods The medical records of 156 consecutive PM/DM patients in 3 medical centers were reviewed. Results Eighteen PM/DM patients (11.5%) developed opportunistic infections. The majority of patients exhibited an opportunistic infection after the onset of PM/DM (89% of cases). Opportunistic infections occurred most frequently during the first year following PM/DM diagnosis (62.5%). The pathogen microorganisms responsible for opportunistic infections were various, i.e., Candida albicans, Pneumocystis carinii, Aspergillus fumigatus, Geotrichum capitatum, Mycobacterium avium‐intracellulare complex, M. xenopi, M. marinum, M. tuberculosis, Helicobacter heilmanii, cytomegalovirus, and herpes simplex virus. Mortality rates were as high as 27.7% in these PM/DM patients. Higher mean daily doses of steroids, lymphopenia, and lower serum total protein levels were significantly more frequent in the group of PM/DM patients with opportunistic infections. Conclusion Our study underscores the high frequency of opportunistic infections in PM/DM, resulting in an increased mortality rate. It also indicates that a great variety of microorganisms are responsible for opportunistic infections, although they were more often due to fungi (>50% of cases). Our series highlights a predominance of both lung and digestive opportunistic infections (89% of cases). In addition, our results suggest that PM/DM patients presenting with factors predictive of opportunistic infection may require closer monitoring.