Acute Clinical Worsening after Steroid Administration in Cervical Myelitis May Reveal a Subdural Arteriovenous Fistula

Abstract

Subdural arteriovenous fistula (SDAVF) is a rare condition characterized by clinical manifestations ranging from mild bilateral sensory deficits to quadriplegia. The diagnosis is often delayed due to unspecific neurological symptoms, initially diagnosed as polyneuropathy or myelopathy. The diagnosis can be delayed for as long as 1–15 years. The following report describes a cervical SDAVF case initially misdiagnosed as myelitis transversa and treated with intravenous steroids. A 56-year-old male presented with sensory deficits and mild leg and right arm weakness. Cervical MRI showed a central medullary hyperintense lesion with contrast enhancement. After metabolic, infectious, and malignant causes were excluded, myelitis transversa was presumed and the patient was treated intravenously with methylprednisolone. Shortly after that, he developed quadriplegia. Cervical MRI imaging showed engorged cervical perimedullary vessels, which were not visible on the initial MRI. The diagnosis was revised and a SDAVF identified. Prompt surgical treatment led to a complete recovery. The effect of intravenous steroids in SDAVF is controversial. Acute clinical worsening after steroid administration is previously reported in several publications; however, due to the paucity of clinical studies on SDAVF, this effect remains mostly overlooked or unknown. The findings in this patient support the causative relation between SDAVF clinical worsening and steroid administration. We propose that acute clinical worsening under steroids in patients initially diagnosed with myelitis should raise suspicion of an SDAVF.

A practical approach to the diagnosis of spinal cord lesions

“…This results in lesions that ascend rostrally from the conus on serial imaging studies. The fistula itself is commonly located in the thoracolumbar cord, with fewer than 2% of fistulae located in the cervical cord,89 and 4% in the sacral region 90. These account for 70% of spinal vascular malformations 91.…”

Acute Tetraparesis with Respiratory Failure after Steroid Administration in a Patient with a Dural Arteriovenous Fistula at the Craniocervical Junction

“…Recently, however, the acute worsening of paraparesis after steroid therapy has been reported in cases of spinal DAVF ( 1 , 2 ). Furthermore, a patient with cervical DAVF who developed sudden brainstem dysfunction after steroid administration has also been reported ( 10 ). The pathogenic role of steroids in these patients is uncertain.…”

“…Hypothetically, the parenchymal lesions of DAVF would be caused by venous hypertension and congestion due to the arterialized venous system of the abnormal arteriovenous shunt ( 11 ). Thus, it was hypothesized that the mineralocorticoid effects of steroids might cause fluid retention, leading to increased venous pressure and a worsening of the symptoms ( 1 , 10 ). Based on these previous reports, the use of steroids in the present case might have triggered the acute exacerbation.…”

Reversible Aggravation of Neurological Deficits after Transforaminal Epidural Steroid Injection in a Patient with Undiagnosed Spinal Dural Arteriovenous Fistula

“…Reported cases of ESI in patients with SDAVF demonstrates that the onset of symptoms is variable (Table 1). Systemic steroid administration alone has shown to cause aggravation of SDAVF symptoms potentially due to water retention and engorgement of the SDAVF [16,17]. This may also explain the variable time in the onset of symptoms in patients receiving ESI.…”