Medical treatment of Serratia arthritis with trimethoprim-sulfamethoxazole.

A patient with moderately severe rheumatoid arthritis and diabetes mellitus receiving steroids developed septic arthritis due to Serratia marcescens. Treatment with a new cephalosporin analogue, intra-articular and intramuscular gentamicin, and chloramphenicol alone and in combination proved ineffective. Finally, trimethoprim-sulfamethoxazole therapy, given for a protracted period, eradicated the infection without the need for surgical drainage.