RESUMO
Valproic acid is a broad-spectrum anticonvulsant that has also gained attention in the psychiatric setting. With respect to safety, valproic acid may induce a seemingly rare condition, hyperammonemia, which can induce a wide variety of symptoms ranging from irritability to coma. The proposed mechanism of hyperammonemia involves depletion of carnitine and overproduction of a toxic metabolite, 4-en-valproic acid, both of which impair the urea cycle and thus ammonia elimination. Carnitine is a commonly used antidote for acute intoxication of valproic acid, but is not a therapeutic option for management of chronic adults with adverse effects related to valproic acid. We herein report a case involving a woman with epilepsy who developed hyperammonemia after a change in her anticonvulsant therapy. She reported increased seizures and gastrointestinal disturbances. Her ammonia, valproic acid, 4-en-valproic acid, and carnitine levels were monitored. Her ammonia level was elevated and her carnitine level was at the inferior limit of the population range. She was supplemented with carnitine at 1 g/day. After 1 month, her ammonia level decreased, her carnitine level increased, and her seizures were better controlled. Carnitine supplementation was useful for reversal of her hyperammonemia, allowing her to continue valproic acid for seizure control.
Assuntos
Anticonvulsivantes/uso terapêutico , Carnitina/administração & dosagem , Hiperamonemia/tratamento farmacológico , Convulsões/tratamento farmacológico , Ácido Valproico/uso terapêutico , Adulto , Feminino , HumanosRESUMO
Objetivo: Estudiar el valor del SPECT cerebral en el diagnóstico y control evolutivo del compromiso del SNC en las enfermedades colágenovasculares (ECV) con sintomatología neuropsiquiátrica (SNP). Materiales y métodos: Se analizaron retrospectivamente 31 pacientes consecutivos portadores de ECV con SNP evaluados mediante SPECT cerebral con 99mTc-ECD y mapas estadísticos de superficie cortical. Veintiuno de ellos presentaban LES y 6 una enfermedad de Behçet. A 18 pacientes se efectuó además TC, a 8 RM y a 10 estudio neuropsicológico (ENP). Seis pacientes se realizaron SPECT de control. Resultados: Veintiocho pacientes presentaron SPECT patológico. La TC fue anormal en sólo 3/18 (sensibilidad 90,3 por ciento vs. 16,7 por ciento; p<0,001). La RM mostró alteraciones en 5/8 pacientes y el ENP en 7/10. Aunque todos estos pacientes presentaron SPECT patológico, los valores de sensibilidad no difirieron significativamente. Los pacientes con mayor SNP presentaron trastornos de perfusión más extensos (p<0,035). Los pacientes estudiados evolutivamente mostraron mejoría de los defectos con la respuesta al tratamiento y agravamiento con la reaparición de síntomas. Conclusiones: El SPECT cerebral presenta elevada sensibilidad en la detección del compromiso neuropsiquiátrico en las ECV. Su utilidad podría extenderse al control evolutivo y la evaluación de la respuesta terapéutica.
Objetive: To study the value of brain SPECT in the diagnosis and follow up of SNC involvement in systemic connective tissue diseases (SCTD) with neuropsychiatric symptoms (NPS). Materials and methods: We retrospectively analyzed 31 consecutive patients with SCTD presenting with NPS who underwent 99mTc-ECD SPECT and statistical surface maps. 21 patients had systemic lupus erythematosus and 3 had Behçet disease. Results were compared to those of CT (18/31), MRI (8/31) and neuropsychological examination (NPE). 6 patients had follow-up SPECT scans. Results: Twenty-eight patients had abnormal SPECT studies. CT was abnormal in 3/18 patients (sensitivity 90.3 percent vs. 16.7 percent; p<0.001). MRI showed alterations in 5/8 patients and NPE in 7/10. Although all these patients presented abnormal SPECT scans, sensitivity values were not statistically different. Patients with major NPS presented more extensive perfusion defects (p<0.035). Patients with follow-up SPECT scans showed perfusion improvement with response to treatment and progression of the alterations when symptoms relapsed. Conclusion: Brain SPECT presents high sensitivity for the detection of neurological involvement in SCTD. SPECT usefulness may extend to follow-up and evaluation of response to treatment.