A woman presented with palmar pustulosis and deep chest pain in association with osteitic lesions in the lower part of the sternum. Propionibacterium acnes was isolated and grew in pure culture from 6 surgically obtained bone specimens. The patient received clindamycin treatment for 6 months. Synovitis in both her wrists persisted and, based on a clinical suspicion of seronegative rheumatoid arthritis, she was treated with intramuscular gold and methotrexate with no apparent benefit. Subsequently, she was diagnosed with SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, and osteomyelitis). Our patient provides further data on the potential association between P. acnes and SAPHO syndrome.