A 32-year-old woman, diagnosed with SLE and antiphospholipid syndrome 6 years ago, monitored in the outpatient rheumatology department, on treatment with prednisone (15 mg a day), ASA (100 mg a day), calcium (1 g), vitamin D (800 u) and omeprazole (20 mg a day). The patient reported fever (40 ºC), predominantly in the evening, of one week's duration, with no other accompanying symptoms. Physical examination revealed only hepatosplenomegaly, with no palpable lymphadenopathy. Blood cultures, urine culture and mantoux were negative; echo-Dopler and chest X-ray were normal; thoraco-abdominal CT scan was normal, except for hepatosplenomegaly with no apparent focal lesions. Laboratory tests showed Hb 6.7, leukocytes 1,000 (400 neutrophils, 500 lymphocytes), platelets 60,000, ANA 1/1,280, anti-DNA 42.3, rheumatoid factor 176, CRP 11.9, C3 122/C4 11.2, proteinogram (gamma globulin 44.2) and normal serology. In view of the possible outbreak of SLE, it was decided to transfuse two red blood cell concentrates, daily injections of C-GSF, boluses of 1 g of methylprednisolone for three days, and amikazin and ceftazidime as empirical treatment for neutropenia. After four days with the treatment described, the fever remained at 40 ºC, with similar laboratory values: in a new analysis, Hb 8.5, leukocytes 1,000 (400 neutrophils, 500 lymphocytes), platelets 32,000, thinking that the symptoms did not correspond to an outbreak of the disease. A sternal puncture was performed and abundant haemoparasites of the genus Leishmania were found, confirming the suspected diagnosis. Treatment was started with liposomal amphotericin B 200 mg per day for 5 days, and the patient became afebrile on the second day. Control laboratory tests 10 days after treatment: Hb 11, leucocytes 2600 (1700 neutrophils) and platelets 97,000 at discharge.