Several viruses and
vaccines are among the environmental factors implicated as triggers of autoimmune
inflammatory myopathies. Case histories report on the onset of
dermatomyositis/
polymyositis after immunization with various
vaccines of patients with probable
genetic predisposition. However, retrospective and epidemiological studies failed to ascertain an association between DM/PM and
vaccines: no significant increase in the incidence of DM/PM was reported after large vaccination campaigns. The risk for
vaccine-induced adverse events may be enhanced by adjuvants.
Macrophagic myofasciitis is a novel
inflammatory myopathy ascribed to an ongoing local immune reaction to a
vaccine adjuvant. Isolated prospective studies showed that the administration of unadjuvanted, non-live
vaccine to patients with DM/PM caused no short-term harmful effects to DM/PM immune processes. However, more research is warranted to clarify the incidence of
vaccine-preventable
infections, harmful effects of vaccination, and the influence of any
immunomodulating agents on vaccination efficacy. Vaccination is an important disease prevention tool in modern medicine. This review does not address risk-benefit or cost-benefit analyses, and does not advocate the use of specific
vaccines or vaccination programs. Despite a great deal of scientific uncertainty, the concept of a possible causal link between immunization and
inflammatory myopathies should not be totally rejected.