Conclusion
xCoxsackievirus A6 infections may cause atypical presentation of HFMD, including small vesicles on faces or vesiculobullous lesions on trunks. The majority of patients were self-limited. The pathogenesis of CVA6-induced bullae should be further investigated.
Patients and methods
Definition of atypical HFMD
The definition of atypical HFMD includes symptoms of acute viral infection (such as fevers, coughs or diarrhea) with either of the following presentations: (1) maculopapular rashes presenting on the trunks, buttocks or facial areas, or (2) large vesicles or bullae on any sites of the body. Patients were classified into two groups according to vesicle sizes by two pediatricians at different points in time. The large vesicle group was defined as having vesciculobullous lesions ≥ 1 cm in diameter; the small rashes group had maculopapular rashes < 1cm in diameter. We compared the clinical symptoms between the two groups.
Inclusion/exclusion criteria
National Taiwan University Hospital is a tertiary medical center in Taipei, Taiwan, with 266 beds in pediatric departments. Children with atypical HFMD were enrolled prospectively through the outpatient clinics and the emergency department between March and December 2010. Children who met the following conditions were enrolled: (1) Under 18 years old, and (2) skin lesions compatible with atypical HFMD. The early presentations of atypical HFMD show two distinct characteristics: (1) bullous lesions on limbs (i.e. elbows and knees), buttocks and trunks, and (2) maculopapular rashes on trunks, earlobes, and facial areas (i.e. periocular region). Compared to these features, children with typical HFMD commonly develop small vesicles (