Arachnoiditis, a complication of epidural blood patch for the treatment of low‐pressure headache: A case report and systematic review

Objective To report a case of arachnoiditis as a complication of epidural blood patch procedures and to systematically review the diagnostic workup, clinical outcomes, and treatment modalities reported in the literature. Background Epidural blood patching is an effective treatment for low‐pressure headache secondary to spontaneous cerebrospinal fluid leak or iatrogenic post‐dural puncture. Spontaneous intracranial hypotension is believed to be a rare headache disorder, but recently has been diagnosed at higher frequencies, making it an important differential diagnosis for intractable headaches. Arachnoiditis has surfaced as a rare complication of epidural blood patching. Symptom presentation does not always correlate with evidence of meningeal enhancement on imaging. Optimal methods for treatment remain largely unknown. Methods Databases Embase and PubMed were searched for all published studies on arachnoiditis post‐epidural blood patch using a combination of the following medical subject headings and keywords: arachnoiditis, arachnoid inflammation, adverse event, and epidural blood patch. All original English‐language articles that described arachnoid and/or meningeal inflammation in conjunction with epidural blood patch procedures were included for analysis. Title and screening, data extraction, and risk of bias assessment were conducted independently and in duplicate by two reviewers. Results Seven other cases of arachnoiditis post‐blood patch placement have been documented, most of which were diagnosed via magnetic resonance imaging. Six of these were a result of a spinal‐epidural anesthesia for labor and delivery. Common symptoms reported were headache, back and radicular pain, paresthesia, and motor weakness. There are currently no proven consensus‐based treatment recommendations available. While intravenous methylprednisolone followed by oral prednisone taper was found to be effective in the case presented, the benefit of other multi‐modal therapies was unclear. Conclusions Headache specialists who treat postural headache should be aware of arachnoiditis as a potentially severe complication of epidural blood patch. The case presented is the first of its kind to report arachnoiditis as a complication of high‐volume blood patch for the treatment of spontaneous intracranial hypotension. More studies are required to determine suitable treatment options for post‐epidural blood patch arachnoiditis.