RESUMO
Limb-girdle muscular dystrophy type 2G/R7 (LGMD2G/R7) is an ultra-rare condition initially identified within the Brazilian population. We aimed to expand clinical and genetic information about this disease, including its worldwide distribution. A multicenter historical cohort study was performed at 13 centers in Brazil in which data from index cases and their affected relatives from consecutive families with LGMD2G/R7 were reviewed from July 2017 to August 2023. Additionally, a systematic literature review was conducted to identify case reports and series of the disease worldwide. Forty-one LGMD2G/R7 cases were described in the Brazilian cohort, being all subjects homozygous for the c.157C>T/(p.Gln53*) variant in TCAP. Survival curves showed that the median disease duration before individuals required walking aids was 21 years. Notably, women exhibited a slower disease progression, requiring walking aids 13 years later than men. LGMD2G/R7 was frequently reported not only in Brazil but also in China and Bulgaria, with 119 cases identified globally, with possible founder effects in the Brazilian, Eastern European, and Asian populations. These findings are pivotal in raising awareness of LGMD2G/R7, understanding its progression, and identifying potential modifiers. This can significantly contribute to the development of future natural history studies and clinical trials for this disease.
Assuntos
Distrofia Muscular do Cíngulo dos Membros , Mutação , Humanos , Distrofia Muscular do Cíngulo dos Membros/genética , Distrofia Muscular do Cíngulo dos Membros/epidemiologia , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Masculino , Brasil/epidemiologia , Feminino , Adulto , Adolescente , Pessoa de Meia-Idade , Criança , Estudos de Coortes , Adulto Jovem , Linhagem , Conectina/genética , Fenótipo , Predisposição Genética para Doença , Pré-EscolarRESUMO
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/virologiaRESUMO
BACKGROUND: Hyperhomocysteinemia has emerged as a novel risk factor for myocardial infarction (MI). Some mechanisms proposed to explain its relationship with coronary events are also shared by major coronary risk factors. We examined whether C677T methylenetetrahydrofolate reductase and A2756G methionine synthase polymorphisms could affect the relative risk for MI. METHODS: A sample of 196 individuals was divided into four groups (diabetics with MI, n=43; diabetics without MI, n=50; non-diabetics with MI, n=47; non-diabetics without MI, n=56) and compared regarding the prevalence of the polymorphisms, risk factors, and biochemical parameters. RESULTS: Higher prevalence of hyperhomocysteinemia was found in MI patients (p<0.05 vs. non-MI subjects), in males (p<0.001 vs. female) and in those > or = 65 years (p=0.01 vs. <65 years). Homocysteine was negatively associated with HDL-C (p<0.05) and glucose, although results did not reach significance (p=0.06). Similar distribution of studied polymorphisms was seen in all groups, which presented normal folate and vitamin B12 serum levels. CONCLUSIONS: Higher homocysteinemia was predominantly observed in men, presenting low HDL-C, and at advancing age. Methylenetetrahydrofolate reductase and methionine synthase polymorphisms did not contribute to risk assessment in diabetic and non-diabetic subjects presenting normal folate levels.