MRI scans of cervical cord provide evidence of anterior horn lesion in a patient with tick‐borne encephalomyeloradiculitis

Meningitis and meningoencephalitis are the prominent symptoms of the central European tick-borne encephalitis (TBE) [1]. In approximately 10% of cases, patients develop myeloradiculitic symptoms with progressive flaccid weakness of limbs and trunk [1,2]. However, it is unclear whether flaccid paresis contributes to radiculitis or reflects poliomyelitic-like anterior horn lesions [2]. This report describes poliomyelitic-like symptomatology as a presenting syndrome in a patient with tick-born encephalomyeloradiculitis and lesions in the anterior horn of the cervical cord revealed by MRI scans. A 43-year-old male presented with rapid progressive flaccid proximal tetraparesis without sensory deficits or pyramidal tract signs. Two weeks before the patient had a tick bite in an endemic area of Ixodes ricinus and TBE in south-west Germany. MRI of the brain was normal, whilst T2-weighted spinal MRI sequences demonstrated limitation of the inflammation to the anterior horns from C3 to T1 in contrast to the spared dorsal columns (Fig. 1). No gadolinium-enhancement was detected. In the cerebrospinal fluid pleocytosis (98/ll) and elevated IgM, IgG and total protein (1800 mg/l) were present. Within 3 days, the patient developed generalized brain oedema and required ventilation for 8 days. Diagnosis of TBE was established by TBE IgG antibody index of 9.70 (<1.5). No other co-infections (borreliosis, herpes simplex and varicella zoster virus) were detected. When a repeat MRI scan of the cervical cord was made 2 weeks later the lesions were no longer detectable. Half a year later, muscular weakness improved to grade 2–3 paresis of the upper and grade 4–5 paresis of the lower extremities. Electromyography revealed proximal denervation. The patient was able to walk with a walking frame.