We describe a 22-year-old female with systemic lupus erythematosus and
lymphopenia, who developed septic arthritis of the right I knee with
Listeria monocytogenes type 1/2 A, whilst on low-dose methotrexate (MT
X). So far, septic arthritis due to this microorganism has been report
ed in two other patients treated with lo low-dose MTX, one having rheu
matoid arthritis and the other psoriatic arthritis. No reports exist o
n patients treated with other cytotoxic antirheumatic therapies.