RESUMO
Serological diagnosis of flavivirus infection is a challenge, particularly in the context of a disease associated with immune response enhancement in a transplant patient, where aspects such as previous flavivirus infections may be involved with the outcome. We report a case of a pediatric patient who developed Guillain-Barré syndrome (GBS) after matched-unrelated hematopoietic stem cell transplantation (HSCT). The patient lives in a Brazilian region that is experiencing an epidemic of Zika virus (ZIKV) and dengue virus (DENV). Because an increasing number of cases of GBS, likely triggered by ZIKV infection, are being reported in Brazil, samples from the patient were tested for both ZIKV and DENV infection. Serological assays strongly suggested a recent ZIKV infection, although infection by DENV or co-infection with both viruses cannot be ruled out. The presence of anti-DENV immunoglobulin-G in donor serum led to the hypothesis that antibodies from the donor could have enhanced the severity of the ZIKV infection. This hypothesis is in agreement with the recent findings that DENV sero-cross-reactivity drives antibody-dependent enhancement of ZIKV infection. These findings highlight the need for discussion of the indication to perform previous flavivirus tests in HSCT donors, especially in areas where ZIKV and other flaviviruses co-circulate.
Assuntos
Vírus da Dengue/imunologia , Dengue/complicações , Síndrome de Guillain-Barré/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecção por Zika virus/complicações , Zika virus/imunologia , Anticorpos Antivirais/sangue , Brasil , Criança , Coinfecção , Reações Cruzadas , Dengue/diagnóstico , Dengue/virologia , Feminino , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/imunologia , Humanos , Imunoglobulina M/sangue , Testes Sorológicos , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/virologiaAssuntos
Ataxia Cerebelar/genética , Neoplasias de Cabeça e Pescoço/genética , Lipoma/genética , Síndrome MERRF/genética , Mioclonia/genética , Alelos , Atrofia , Biópsia , Ataxia Cerebelar/diagnóstico , Cerebelo/patologia , DNA Mitocondrial/genética , Disartria/diagnóstico , Disartria/genética , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Lipoma/diagnóstico , Síndrome MERRF/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Mioclonia/diagnóstico , Exame Neurológico , Mutação Puntual , RNA de Transferência de Lisina/genética , Tomografia Computadorizada por Raios XRESUMO
We describe two cases of palatal myoclonus (PM), one essential and another secondary to a stroke. Case 1: a 64 years old female who developed clicking sounds in both ears after a stroke and three years later on noticed a progressive involuntary movement of the throat associated with rhythmic contractions of the soft palate, muscles of tongue and throat. MRI showed an ischemic area in brainstem. The patient had a partial response to the use of sumatriptan 6 mg subcutaneously. Case 2: a 66 years old female who began with ear clicking at left ear that worsed slowly associated with tinnitus and arrhythmic movements of soft palate and an audible click at left ear. Brain MRI was normal; audiometry showed bilateral neurosensory loss. She was prescribed clonazepan 1 mg daily with complete recovery. Primary and secondary palatal myoclonus share the same clinical features but probably have different pathophysiological underlying mechanisms
