Reversible posterior leukoencephalopathy syndrome of bilateral thalamus in acute lymphoblastic leukemia

Numerous cases of reversible posterior leukoencephalopathy syndrome (RPLS) are reported in patients having risk factors such as malignant hypertension, eclampsia, receiving solid organ/hematopoietic stem cell transplant, and exposure to chemotherapeutic agents and immunosuppressive drugs. We experienced a very interesting case of atypical RPLS in the thalamus bilaterally accompanied by brain hemorrhage in acute lymphoblastic leukemia (ALL), and described here. A 62-year-old Japanese female was referred to our hospital with fever, general fatigue and leukocytosis in May 2011. Her white blood cell count was 139.6 10 9 /L, of which lymphoblasts constituted 96%, hemoglobin level was 8.2 g/ dL and platelet count was 15.0 10 9 /L. Leukemic lymphoblasts were peroxidase negative and their surface markers were positive for CD10, CD19, CD34 and human leukocyte antigen (HLA)-DR. Th e karyotype was 46, XY; the BCR/ABL fusion gene was not detected. Th e patient was diagnosed as having ALL and treated with cyclophosphamide, vincristine, adriamycin and prednisolone. Although leukemia cells were not present in peripheral blood at 9 days after starting chemotherapy, febrile neutropenia occurred, and antibiotic treatment was started immediately. After the administration of antibiotic and antifungal agents, erythroderma developed on her trunk, extremities and back. Stevens – Johnson syndrome (SJS) was diagnosed, and high-dose methylprednisolone was given. Hyponatremia (124 mEq/L) also occurred at this time, as an eff ect of the chemotherapeutic agents. Although the erythroderma and hyponatremia improved slowly over the next 4 days, her level of consciousness decreased gradually before falling suddenly, accompanied by high fever. Blood culture was positive for Pseudomonas aeruginosa while cerebrospinal fl uid (CSF) culture was negative. Th e patient ’ s level of consciousness improved after antibiotic treatment for sepsis; however, she lost consciousness once more, accompanied by high blood pressure (180/118 mmHg). Emergency computed tomography (CT) of the brain revealed multiple low-density areas in the thalamus, midbrain and pons bilaterally. Magnetic resonance imaging (MRI) of the brain performed 2 days after the CT scan showed multiple high signal intensity lesions with small hemorrhagic areas on T2-weighted fl uid attenuated inversion recovery imaging, T2 star-weighted imaging and diff usion-weighted imaging (Figure 1). No thrombosis of the bilateral internal vein and Galen vein was detected in brain CT and MRI. At 10 days after completion of treatment for sepsis and control of blood pressure, the patient was fully conscious. She was diagnosed with hemorrhage in atypical RPLS. MRI obtained 2 months after treatment showed no RPLS lesions