Abstract
This report describes an 11-year-old girl with systemic lupus erythematosus (SLE) with long-standing low levels of complement proteins. A disease period with lupus nephritis (class IIIa) was complicated by Staphylococcus aureus bacteraemia and osteomyelitis. She was treated with high-dose immunosuppressants and 6 weeks of high-dose intravenous antibiotics. The clinician should be aware of bacteraemia in SLE with secondary complement deficiency.