Herpes simplex virus 1 encephalitis associated with voltage-gated calcium channel autoimmunity

Encephalitis is a significant cause of morbidity and mortality, yet a causative factor is identified in <50% of cases. 1 The most common causes are infectious (particularly herpes simplex virus [HSV]) and autoimmune. 2 Diagnosis of the latter potentially treatable cause is aided by the detection in serum or CSF of an informative profile of autoantibodies against neuronal intracellular proteins and plasma membrane proteins (e.g., voltage-gated potassium channel [VGKC] complex and calcium channels [VGCC, P/Q-type or N-type] and a growing list of glutamate receptors [R] and other autoantibodies of synaptic specificity). 3,4 Neural autoantibodies, particularly NMDA-R-IgG, have recently been reported in the setting of viral encephalitides. 5,6 Herein, we report a unique case of N-type VGCC autoantibody temporally associated with HSV encephalitis.