A case report of a teenager with severe hand, foot, and mouth disease with brainstem encephalitis caused by enterovirus 71

Hand, foot, and mouth disease (HFMD) is an acute viral infection occurring mostly in infants and children. Enterovirus 71 (EV71) infection mostly occurs in children < 5 years of age. Severe cases, however, are usually encountered in children under the age of 3 years, and exceedingly rare in teenagers > 14 years and adults.

We report a rare case of HFMD in a 16-year-old male teenager residing in Chonqing, China. The clinical presentation was typical of HFMD and included vesicular lesions and oral mucosal ulcers, macular and vesicular lesions on palms and soles. He developed severe neurological complications that were suggestive of brainstem encephalitis. EV71 RNA was detected in the patient’s faecal samples by reverse transcription-polymerase chain reaction. Specific IgM antibody to EV71 was detected in both serum and cerebrospinal fluid by ELISA. Gamma immunoglobulin therapy at 25 g/day was administered for 2 days, along with methylprednisolone, mannitol, ganglioside, and creatine phosphate sodium. The patient showed neurological improvement and recovered completely in 1 month.

This case indicates that EV71 infection may cause HFMD in teenagers with potentially severe neurological involvement. Clinicians should be aware of the possibility of HFMD occurring in adults and teenagers as prompt treatment could be life-saving in these patients.