Kikuchi-Fujimoto Disease (KFD) is a rare benign condition of necro- tizing histiocytic lymphadenitis. The manifestations include localized lymphadenopathy, fever and weight loss. KFD has been described in association with systemic lupus erythematosus (SLE). This case describes a patient whose anorexia and deterioration were first interpreted as a manifestation of her schizophrenia. Diagnosis of a rare organic treatable disease resulted in improvement in her life threa- tening condition. A 36-year-old woman with schizophrenia treated with depot halo- peridol experienced a general deterioration, extreme anorexia and fever up to 38°C for few months. On examination she was cachectic weighing 33kg and confined to bed. She had malar rash, cough, fever, and enlarged axillary lymph nodes. Primary laboratory tests revealed pancytopenia and LDH 1254U/L. For suspected atypical pneumonia, therapy with ceftriaxone and azithromycin was started with no improvement. Cotrimoxazole was initiated and appropriate tests ruled out PCP, TB and HIV. Her condition deteriorated further demonstrating neutropenia 600mm3, and coombs positive hemolytic anemia with hemoglobin 8g/L. Further lab tests revealed: positive ANA with titer of 1:60, elevated anti-smith, anti-RNP levels more than 200U. Anti-double stranded DNA was negative, C3: 62mg/dL, 24 hour protein urine collection showed 3.8g with no casts in urinary sediment. A total body CT scan revealed pleural effusion, enlarged axillary and mediastinal lymph nodes. A biopsy form a right axillary lymph node revealed histiocytic necrotizing lymphadenitis. The diagnosis of KFD associated with SLE was made based on a malar rash, pleural and pericardial effusion, nephrotic range proteinuria, positive ANA, Anti- Smith, Anti-RNP, pancytopenia and a positive coombs test. The pathology result was consistent with KFD. A follow up cardiac echocardiogram showed a new large pericardial effusion with right atrial compression and tachycardia. Parallel to high dose IV methylprednisolone treatment, a pericardiocentesis was per- formed and only 250ml were aspirated because of septations. A ster- notomy with a pericardial window was performed. Following this procedure the patient's condition improved. Therapy with azathioprine 75mg/day and Prednisone 40mg/day was started. A second CT scan showed that the previously shown lymph nodes disappeared. Physiotherapy was started on admission and continued ongoing. Five months after admission the patient maintains a significant improvement in her daily function and activity. She gained 15kg. There was a decrease in her proteinuria and increase in the C3 level to 93 with a normal blood count. To conclude, we describe a case of KFD, a rare disease evolving in a SLE patient. Both diagnoses were made relatively late in the course of a chronic schizophrenic patient, leading to the appropriate therapy and saving her life.