Autoimmune and rheumatic diseases are two close allies. Differential diagnosis of both disease groups can be cumbersome since the clinical signs of rheumatic and infectious disorders are very similar. This book addresses the fact that infectious disease can either mimic or complicate rheumatic diseases. In the first part, cases of with standard rheumatic symptoms patients triggered by infections and differential diagnosis are presented. The second part is dedicated to the complications of rheumatic disease infections. Standard patient cases are presented as well as risk factors, clinical features and microbial spectra. Further chapters inform about the impact of anti-rheumatic and immunomodulatory drug therapies (incl. biological agents) on infectious risk, the specific aspects of vaccination during immunosuppressive therapy and issues about the infectious risk and chemoprophylaxis during orthopedic surgery. This book provides clinicians a detailed insight between rheumatic and infectious disease.