GABAA receptor encephalitis associated with human parvovirus B19 virus infection: Case report

Abstract

Rationale: Human parvovirus B19 (B19) infection can produce a spectrum of clinical syndromes, including neurological manifestations, most notably encephalitis. Although symptoms suggestive of autoimmune disease in patients with B19 infection have been previously described, a clear association of autoimmune encephalitis with B19 infection has yet to be established.

Patient concerns: We describe the case of a 6-year-old boy who was hospitalized due to status epilepticus, which evolved to super-refractory status epilepticus that was only mildly responsive to anticonvulsant drugs.

Diagnosis: A cerebrospinal fluid study identified slight pleocytosis and B19 positivity. A subsequent autoimmunity cerebrospinal fluid study revealed the presence of anti-γ-aminobutyric acid type A (GABAA) receptor antibodies.

Interventions: After pulse therapy with methylprednisolone and continuous therapy with prednisolone with cyclosporine, the patient experiencing seizure persistence with disordered motor function manifestations and only minor improvement in consciousness, and so, plasmapheresis was performed. With continued immunosuppressive treatments with cyclosporine and prednisolone, the patient's clinical picture showed progressive improvement, with good control of seizures. Although the patient tolerated withdrawal of the anticonvulsant drugs well, he developed seizures when corticosteroid therapy withdrawal was attempted, so was started on azathioprine.

Outcomes: After immunosuppressive therapy, the patient evolved with complete remission of symptoms, normal neurological examination and age-appropriate neuropsychomotor development.

Lessons: The present case characteristics, together with previous findings, support the hypothesis that autoimmunity may be triggered by extensive antigen release due to degeneration of infected neurons. This case highlights the importance of early clinical suspicion and treatment.

Figure 1

Brain MRI of a pediatric patient with autoimmune anti-GABA_A receptor encephalitis comorbid with an established B19 infection of the central nervous system at two timepoints. A–D. Images from the patient's first MRI scan, which occurred while he was being treated in the ICU for persistent seizures that evolved into focal SE with fluctuating consciousness. T2/FLAIR hyperintensity and mild expansion in the left cerebellar hemisphere, with some foci of contrast enhancement and an absence of restricted diffusion. E–H. Images from a follow-up scan performed almost a month later, likely showing residual post-inflammatory changes. Note that the previously observed T2/FLAIR hyperintensity and volume expansion were reduced and that there were no new lesions or areas of contrast uptake in the left cerebellar hemisphere.

Figure 2

Timeline with treatment progression and diagnosis time. D, day; ICU = intensive care unit; IgG, IgA, immunoglobulin.