[Incidence and determinants of levodopa-induced dyskinesia in a retrospective cohort of Mexican patients with Parkinson's disease]. / Incidencia y determinantes de discinesias inducidas por levodopa en una cohorte retrospectiva de pacientes mexicanos con enfermedad de Parkinson.

UNLABELLED: BACKGROUND. Levodopa-induced dyskinesia is one of the main complications and limitations of the treatment of patients with Parkinson's disease. OBJECTIVE: To determine the incidence and risk factors involved in the development of dyskinesias in a retrospective cohort of Mexican patients with Parkinson's disease. MATERIAL AND METHODS: We reviewed a total of 601 cases of Parkinson's disease patients treated at the National Institute of Neurology and Neurosurgery in the period between January 1990 and June 2010; 482 of them had history of exposure to levodopa. RESULTS: The follow-up was equivalent to 4,392 person-years. 154 patients had dyskinesias at some point in the evolution of the disease. The person-time incidence was 35 cases per 1,000 person-years. The onset of motor symptoms before 50 years of age and levodopa doses > or = 600 mg of levodopa were the main risk factors for early development of dyskinesia (HR of 1.01 [95% CI 1.0 to 1.01, p = 0.001] and HR 1.10 [95% CI 1.04 to 1.23, p = 0.04], respectively]. CONCLUSION: The main determinants of dyskinesias were present early age of onset of motor symptoms and the dose of levodopa. Knowledge of these factors will improve the management planning.

Inguinal lymph nodal metastasis of myxopapillary ependymoma confirmed by fine-needle aspiration cytology, biopsy, and immunohistochemistry: case report.

Ependymoma (EP) rarely metastasizes outside the central nervous system. Inguinal nodule metastasis of EP more than 10 years after surgical resection and radiotherapy is extremely rare. We report a man aged 38 years who underwent surgery for lumbosacral myxopapillary EP at the age of 22 years and was treated with several cycles of radiotherapy. The patient was reoperated for residual tumor and received two complete cycles of radiotherapy for 11 years. Biopsies were always diagnosed as myxopapillary EP. Five years after the last surgical excision, the patient developed abdominal pain and inguinal lymphadenopathy. Biopsy was performed by fine-needle aspiration and was proven malignant epithelial neoplasm with a myxoid background, was diagnosed as metastasis of EP. Biopsy showed an anaplastic EP grade III. EP is often recurrent at the primary site but can seed on the entire cerebrospinal axis. We describe the clinical features of this rare lesion and particularly emphasize the need for long-term follow-up, for more than 10 years after the initial treatment, in patients with EP and malignant transformation after radiotherapy.