corticosteroids, immunosuppressive agents, and/or plasmapheresis Treatment of GI hemorrhage is described in the “Gastrointestinal Complications” section Although less common than in systemic juvenile idiopathic arthritis (sJIA), disseminated intravascular coagulation (DIC) associated with macrophage activation syndrome (MAS) may occur in SLE, with or without an associated infection Therefore, patients with thrombocytopenia and severe bleeding should be investigated with prothrombin time, partial thromboplastin time (PTT), fibrin split products, ferritin, and examination of the peripheral smear Lupus also appears to predispose to a particularly malignant form of thrombotic thrombocytopenic purpura Mortality rates are high, despite general support in ICUs and aggressive treatment with pheresis and immunosuppression Outcomes are optimal when the diagnosis is suspected early and treatment is initiated rapidly The presence of a circulating lupus anticoagulant does not lead to a bleeding diathesis unless associated with significant thrombocytopenia; on the contrary, these patients are at increased risk of deep venous or arterial thrombosis Prolongation of PTT and chronic false-positive serologic tests for syphilis are the usual clues to the presence of these autoantibodies Antiphospholipid antibodies may also be measured, and the antiphospholipid antibody syndrome is associated with significant morbidity and mortality Significant thrombosis or pulmonary embolus in a child with SLE is an indication for immediate anticoagulation Neurologic Complications Seizures (see Chapter 72 Seizures ) and altered states of consciousness (see Chapters 17 Coma and 97 Neurologic Emergencies ) are the most common manifestations of CNS involvement in SLE Other possible causes of seizures in patients with SLE include hypertension, infection (meningitis, encephalitis, or abscess), and uremia Coma is not a primary manifestation of SLE but may result from meningitis or CNS hemorrhage related to thrombocytopenia Therefore, patients with SLE who develop seizures or altered states of consciousness require urgent imaging, specifically a computed tomography (CT) scan, with and without contrast Magnetic resonance imaging (MRI) may be required because the differential diagnosis includes lupus cerebritis Patients should have repeated assessments with special attention to blood pressure and neurologic findings, as well as the following investigations: CBC, PT/PTT, electrolytes, BUN, creatinine, and urinalysis Once space-occupying lesions have been excluded, lumbar puncture (including measurement of opening pressure) should be performed, with CSF sent for routine studies as well as special stains to look for opportunistic organisms such as fungi and acid-fast bacilli If CNS manifestations are believed to be caused by active vasculitis, IV corticosteroid therapy should be initiated In the presence of deteriorating mental function, “pulse” methylprednisolone (30 mg/kg, 1.5 g maximum), IV cyclophosphamide, or plasmapheresis may be beneficial