A healthy 33-year-old, right-handed Caucasian patient experienced two episodes of post-partum RE in 2015 and 2017 (Fig. 1). The first episode occurred five months after a normal vaginal delivery of her first child. She presented to the emergency department with progressively worsening right-sided dysmetria, adiadochokinesia, weakness, ataxia, and photophobia. Past medical history showed that the patient was well. The patient had other than an infectious mononucleosis at age 16. She started progestin oral contraceptives a few months after the deliveries and had no known allergies. She denied any substance use, including alcohol, tobacco, and recreational drugs. Review of systems and physical examinations were otherwise unremarkable. The patient’s mother had systematic lupus erythematous (SLE).
Gadolinium-enhanced MRI revealed a large area of FLAIR (Fluid attenuated inversion recovery) and T2 hyperintensity that crossed the midbrain but did not involve the colliculi nor the pons, suggesting a form of RE (Fig. 2). Extensive investigations with blood and cerebrospinal fluid failed to yield any underlying etiology, such as infectious, metabolic, vascular, or demyelinating disease. Potentially abnormal findings included the following: CBC with neutrophilia (7,800 cells/µL) and leukocytosis (5,000 cells/µL); CSF analysis with albumin 53.1 mg/dl (37-51), α1 globulin 5.4% (6.1-10.5), and β globulin 3.9% (4-7.2); and viral serology with positive Epstein-Barr virus IgG and nuclear antigen, but negative IgM. Although she had no underlying autoimmune condition, the ANA screen came back positive for ACA.
Viral and atypical infections tested were Human immunodeficiency virus, Enterovirus, Herpes simplex, Cytomegalovirus, Varicella Zoster, Powassan virus, Eastern equine encephalitis, Jamestown Canyon virus, arbovirus, West Nile virus, Toxoplasma, Mycobacterium tuberculosis, Treponema pallidum, Listeria monocytogenes, and Borrelia burgdorferi. Autoimmune screening included oligoclonal band, anti-NMO antibodies, cryoglobulins, complement levels, thyroid antibodies, and other autoimmune antibody panels associated with encephalitis and paraneoplastic syndrome. Conditions, including collagen disease, vasculitis, stroke, Behçet, and Hashimoto encephalopathy, could not be diagnosed with established criteria. Based on these findings and clinical symptoms, RE was diagnosed. Without a clear etiology, the patient was treated empirically with parenteral acyclovir 600 mg, ampicillin 2 g, and methylprednisolone 1 g. Complete resolution of symptoms and reversal of radiologic abnormalities were achieved.
Four months after the delivery of a second child, the patient presented to the ER with an acute onset of right-sided dysmetria, weakness, ataxia, photophobia, and blurred vision on the left eye. She was admitted to the hospital and seen by neurology. Physical exam revealed a slight relative afferent pupillary defect on the left eye and mild blurring of the optic disk bilaterally with normal visual field and extra-ocular movements. Comprehensive investigations were conducted with additional tests in cytology and microbiology. Whipples disease and potential malignancies were ruled out.
T2-FLAIR MRI showed hyperintensity involving the same region of midbrain, but less extensive than the one observed in the first episode, suggesting that the patient had a recurrent RE. The patient was again positive for ACA. The rest of the exams and tests were essentially normal. Given the negative infectious work up in the prior episode and the nearly identical clinical presentations, we decided to treat the patient with corticosteroid, notably IV methylprednisolone 500 mg. This fully reversed her clinical symptoms and MRI lesions with no serious adverse events. At 10 months follow-up, routine investigations and examinations were normal with no residual neurological deficits. However, ACA remained positive.