A 3-year-old boy with Guillain–Barré syndrome and encephalitis associated with Mycoplasma pneumoniae infection

Abstract Mycoplasma pneumoniae is a common cause of respiratory tract illness in children. Among the most common extrapulmonary manifestations are disorders of the central nervous system, including meningitis, meningoencephalitis, cerebellitis, polyneuropathy, acute disseminated encephalomyelitis, and Guillain–Barre syndrome. Guillain–Barre syndrome, also known as acute inflammatory demyelinating polyradiculoneuropathy, is an acute-onset, immune-mediated disorder of the peripheral nervous system. The central nervous system is usually intact in patients with Guillain–Barre syndrome. However, there have been some reports of an association of Guillain–Barre syndrome with central nervous system involvement in children. We report a 3-year-old boy with M. pneumoniae infection associated with Guillain–Barre syndrome and encephalitis. Both serum anti-GM1 ganglioside (IgG and IgM) and anti-galactocerebroside IgG antibodies were detected in our patient: the former in the earlier stage of the disease, and the latter in the later stage. We speculate that anti-GM1 ganglioside was associated more with encephalitis, and anti-galactocerebroside antibody was associated more with GBS in our case. Our patient is the youngest report of Guillain–Barre syndrome with central nervous system involvement, and the first report of a pediatric patient with associated M. pneumoniae infection. Such cases are rarely reported, but highlight the need for awareness of the association of the infection with Guillain–Barre syndrome with central nervous system involvement.