Cortical hypointensity in T2-weighted gradient-echo sequences in patients with progressive multifocal leukoencephalopathy. / Hipointensidad cortical en secuencias eco de gradiente T2 en la leucoencefalopatía multifocal progresiva.

INTRODUCTION: Progressive multifocal leukoencephalopathy is a demyelinating disease of the central nervous system caused by the reactivation of the JC virus. This opportunistic encephalopathy mainly affects immunodepressed patients with stage III HIV infection, although in recent years it has also been found in association with treatment with immunosuppressors such as natalizumab. MRI plays an important role in both the early diagnosis and follow-up of this disease. Recently, it has been reported that hypointensities in U-fibers and cortex adjacent to white-matter lesions characteristic of the disease can be identified on T2-weighted gradient-echo and susceptibility-weighted sequences in patients with progressive multifocal leukoencephalopathy. OBJECTIVE: We aimed to analyze the presence and usefulness of cortical hypointensity on T2-weighted gradient-echo sequences in relation to the diagnosis of progressive multifocal leukoencephalopathy and to review the literature on the topic. MATERIAL AND METHODS: We analyze three cases of progressive multifocal leukoencephalopathy seen at our center in three patients with immunosuppression of different origins: one with stage III HIV infection, one with multiple sclerosis being treated with natalizumab, and one with rheumatoid arthritis being treated with rituximab. RESULTS: In all three cases MRI showed the cortical hypointensity adjacent to the white-matter lesion in the T2-weighted gradient-echo sequence. In the patient with multiple sclerosis, this sign appeared earlier than the abnormal signal in the white matter. The patient being treated with rituximab was diagnosed postmortem and the pathology findings correlated with the MRI findings. CONCLUSION: The finding of cortical hypointensity on T2-weighted gradient-echo MRI sequences seems to support the diagnosis of progressive multifocal leukoencephalopathy, regardless of the type of immunosuppression, so this finding should routinely assessed in patients suspected of having this disease.

[Primary central nervous system lymphoma in a unusual site: a diagnostic challenge]. / Linfoma primario del sistema nervioso central de localizacion inhabitual: un reto diagnostico.

TITLE: Linfoma primario del sistema nervioso central de localizacion inhabitual: un reto diagnostico.

Prevalence and concordance between the clinical and the post-mortem diagnosis of dementia in a psychogeriatric clinic. / Prevalencia y concordancia entre diagnóstico clínico y anatomopatológico de demencia en una clínica psicogeriátrica.

INTRODUCTION: The aim of our study is to describe the types of dementia found in a series of patients and to estimate the level of agreement between the clinical diagnosis and post-mortem diagnosis. MATERIAL AND METHODS: We conducted a descriptive analysis of the prevalence of the types of dementia found in our series and we established the level of concordance between the clinical and the post-mortem diagnoses. The diagnosis was made based on current diagnostic criteria. RESULTS: 114 cases were included. The most common clinical diagnoses both at a clinical and autopsy level were Alzheimer disease and mixed dementia but the prevalence was quite different. While at a clinical level, prevalence was 39% for Alzheimer disease and 18% for mixed dementia, in the autopsy level, prevalence was 22% and 34%, respectively. The agreement between the clinical and the autopsy diagnoses was 62% (95% CI 53-72%). CONCLUSIONS: Almost a third of our patients were not correctly diagnosed in vivo. The most common mistake was the underdiagnosis of cerebrovascular pathology.

[Long-term evolution of a patient diagnosed of small lung cancer with extension to the central nervous system]. / Larga evolución de un paciente diagnosticado de cáncer microcítico de pulmón con afectación del sistema nervioso central.

Cell lung cancer is the principal cause of cancer death in men and women. We report the case of a man diagnosed with small cell lung cancer, metastatic from the outset. The disease is stable at present, forty-seven months from dia-gnosis, after receiving different treatment modalities.