Leukoencephalopathy due to oral methotrexate.

Methotrexate (MTX) is considered the main agent for the treatment of rheumatoid arthritis (RA). Neurotoxicity is often mild, but severe encephalopathy can develop, especially with intrathecal or intravenous administration. In rare cases, this syndrome has been observed in patients on long-term low-dose oral administration. A 68-year-old male was diagnosed with RA and on treatment with oral MTX 25 mg weekly for 4 years. The patient started with progressive dysarthria, ataxia and cognitive dysfunction. Complementary tests were normal. Magnetic resonance imaging (MRI) showed hyperintense lesions in both cerebellar hemispheres on T2-weighted and FLAIR images with a diffusion restriction on diffusion-weighted imaging (DWI) and on the apparent diffusion coefficient map (ADC). On postgadolinium T1-weighted images, there were mild enhancements. Spectroscopy showed a demyelinating pattern. A pharmacogenetics determination was made, showing a heterozygous genotype in the MTHFR and ABCB1 genes. Medication with antirheumatic drug was stopped immediately on admission, and the patient gradually improved. MTX-induced leukoencephalopathy can occur even with low-dose administration. The exact pathogenic mechanism is still unknown, but it is hypothesised that it could be the result of a cumulative toxic effect on the blood-brain barrier. The nature of the relationship between the polymorphism and CNS toxicity is still unclear, and thus, further studies are warranted. Often located in the occipital lobes, the involvement of the cerebellum is quite rare. Early recognition of the condition and withdrawal of the drug lead to a better prognosis.

Stroke due to septic embolism resulting from Aspergillus aortitis in an immunocompetent patient.

INTRODUCTION: Cerebral infarction secondary to Aspergillus arteritis or septic embolism is an exceptional finding. We present a case of multiple systemic embolism and cerebral infarction resulting from Aspergillus aortitis in an immunocompetent patient. PATIENT: A 65-year-old male with hypertension, hyperglycaemia and myocardial infarction with aorto-coronary by-pass surgery three years before admission, that suffered cerebral infarction in middle right cerebral artery territory and right cubital artery embolism. One month later he presented abrupt increase of his left hemiparesia and left central facial palsy associated with fever of unknown origin. Laboratory test, cranial CT and echocardiogram were performed. He died ten days later. RESULTS: Hemogram: leucocytes 34.700/microL (85% N, 4.8%L). Cranial CT: cerebral infarction in middle right cerebral artery territory. Transthoracic and transesophageal echocardiogram: moderate left ventricular hypertrophy and slight inferior hypokinesis. Arteriography: complete thrombosis of the left internal carotid. Necropsy: parietal aortic aspergillosis with generalized septic embolisms (brain, kidney, liver, fingers), cerebral infarction in middle right cerebral artery territory and thrombosis of the left carotid siphon with Aspergillus arteritis. CONCLUSIONS: Aspergillosis is an exceptional cause of cerebral infarction, especially in immunocompetent patients, and their diagnosis is complicated, being usually found at necropsy.