BACKGROUND Enterovirus (EV) A71 and coxsackievirus (CV) A16 were the most frequent serotypes involved in hand, foot, and mouth disease (HFMD) outbreaks throughout Asia. In the past 5 years, however, CV-A6 has emerged as a new important pathogen worldwide, and more severe and extensive dermatologic presentations has been reported. OBJECTIVES Identify the clinical spectrum for atypical HFMD and enterovirus serotypes in Belém, Pará, Amazon region of northern Brazil. STUDY DESIGN A prospective ambulatory clinic-based surveillance conducted from January to June 2019, involving patients under 15 years with symptoms of HFMD. Stool, serum, oropharyngeal, and skin swab samples were analyzed. Real-time RT-PCR was performed to detect the viral genome of enteroviruses. Positive specimens were submitted to semi-nested PCR. Physical examinations and demographic data were recorded on a standardized form. RESULTS 48 patients with symptoms of HFMD were included in the study and collected all samples according to protocol. Enteroviruses were detected in 83 % of patients. An atypical form of HFMD with vesiculobullous exanthema was present in 70 % (28/40); desquamation of the palms and soles detected in 90 % (36/40) and onychomadesis in 30 % (12/40) of patients. The serotype was identified in 22 patients, CV- A6 occurred in 81.8 % of them. CONCLUSION This is the first ambulatory surveillance and virologic investigation involving HFMD performed in outpatients from Amazon region, Brazil. The detection of CV-A6 was related to atypical forms HFMD. Desquamation of the palms and soles and nail changes occurred with frequency, such as a late sequel in the HFMD disease.

中文翻译：

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在巴西北部亚马逊地区贝伦的非典型手足口病中发现了柯萨奇病毒A6。

背景肠道病毒（EV）A71和柯萨奇病毒（CV）A16是整个亚洲最常见的手足口病（HFMD）爆发血清型。然而，在过去的5年中，CV-A6已成为一种新的重要的全球病原体，并且已经报道了更严重和广泛的皮肤病学表现。目的确定巴西北部亚马逊州贝伦贝伦非典型手足口病和肠病毒血清型的临床范围。研究设计于2019年1月至6月进行的基于门诊的前瞻性监测，涉及15岁以下患有手足口病症状的患者。分析了粪便，血清，口咽和皮肤拭子样本。进行实时RT-PCR以检测肠病毒的病毒基因组。将阳性标本进行半巢式PCR。体格检查和人口统计学数据以标准化形式记录。结果本研究纳入48例手足口病症状患者，并根据方案收集所有样本。在83％的患者中检测到肠病毒。70％（28/40）的非典型型手足口病伴囊泡性皮疹。90％（36/40）的患者出现手掌和足底脱屑，30％（12/40）的患者出现甲癣。在22名患者中鉴定出血清型，其中81.8％发生CV-​​A6。结论这是首次对来自巴西亚马逊地区门诊病人的手足口病进行动态监测和病毒学调查。CV-A6的检测与非典型手足口病有关。手掌和脚掌的脱屑和指甲随频率发生变化，例如手足口病的后遗症。