Immunosuppressants induced reversible posterior dominant emcephalopathy-A capillary leak syndrome

ABSTRACT

BACKGROUNDS Recently, the cases with transient neurologic deficit and brain MRI abnormalities similar to hypertensive encephalopathy or eclampsia were reported in the organ transplanted patients, during the administration of cyclosporine with the hypothesis as "capillary lack syndrome". But in addition to cyclosporine, other immunosuppressive agents as cytabine and ant-lymphocyte globulin(ALG) may induce similar transient neurologic manifestations such headache, seizure, altered mental state and change of signal intensities in brain MRI. METHODS AND CASES 11 patients who had suffered form hematologic disorder were included in the study. The patients were presented with a reversible transient neurologic manifestations and brain MRI abnormalities during administration of various immunosuppressant,. We analysed neourologic symptoms and signs, anatomic localizations and laboratory findings. RESULTS: The underlying hematologic disorder were severe aplastic anemia acute lymphocyte leukemia, multiple myeloma, chronic myelocytic leukemia and acute myelocytic leukemia. The cyclosporine was prescribed in six. ALG in three, idarubicin in two and prednisolone in one patient. The accompanied neurologic symptoms and sign were seizure(11/11), visual disturbance or cortical blindness(5/11) and mental status change(3/11). All the symptoms were spontaneously improved by conservative management. The insidious increase on blood pressure, hepato-renal impairment, sepsis, and hepatopathy were noted in some cases just before and after the neurologic manifestation. The ESR was elevated in all examined cases and the cholesterol level was normal. Serum cyclosporine was elevated in 2/6 cases. They showed typical MRI findings which were high signal intensity an T2WI and iso- to low signal intensity on TIWI with blunding of cortical sulci and with no enhancement. The involved lesions were the parieto-occipital area, frontal lobe, temporal lobe, and basal ganglia in series. One patient showed a petechial hemorrhage in the occipital area on both CT and MRI. In six cases, follow-up MRI showed nearly complete resolution of the lesions correlated with the clinical symptoms. CONCLUSION: We can't explain the exact mechanisms of the neurologic complication of immunosuppressants, but the characterstics of transient neurologic deficits and the corresponding reversible brain image are similar to those of hypertensive encephalopathy or eclampsia. It is suggested that the mechanism of clinical syndrome maybe a capiliary leak due to the cytokine-induced vasculopathy but future studies are warranted.