Post–COVID‐19 vaccine small‐fiber neuropathy and tinnitus treated with plasma exchange

Abbreviations

COVID‐19coronavirus disease‐2019PLExplasma exchangePOTSpostural orthostatic tachycardia syndromeSARS‐CoV‐2severe acute respiratory syndrome coronavirus‐2SFNsmall‐fiber neuropathy

Small‐fiber neuropathy (SFN) is a known complication of vaccinations, including the coronavirus disease‐2019 (COVID‐19) mRNA vaccines. 1 A 52‐year‐old man received the BNT162b2 mRNA COVID‐19 vaccine. After two doses, he had paresthesias as well as burning and stabbing pain in the arms, face, and eyes, accompanied by high‐pitched right ear tinnitus. He subsequently developed orthostatic intolerance and was unable to stand and walk without syncope. These symptoms progressed for 5 months and cardiac monitoring revealed significant postural tachycardia with heart rate varying from 50 beats per minute (bpm) supine to 180 bpm standing with episodes of supraventricular tachycardia. Neurological examination was normal except diminished sensation to temperature in the feet.

The following laboratory tests were normal or negative: comprehensive metabolic profile, complete blood count, vitamin B12 and B6 levels, thyroid‐stimulating hormone, homocysteine, methylmalonic acid, serum protein electrophoresis with immunofixation, paraneoplastic antibody profile, antinuclear antibody, double‐stranded DNA, Lyme antibody, C‐reactive protein, and erythrocyte sedimentation rate. Hemoglobin A1C was mildly elevated at 5.7%. Electromyography and nerve conduction studies were normal in the upper and lower extremities. Skin biopsy revealed decreased epidermal nerve fiber density of 2.2/mm² (normal 13.8) at the distal leg and 7.5/mm² at the thigh (normal 21.1). MRI of the brain and internal auditory canals was unremarkable. Expanded antibody testing (CellTrend Laboratories, Luckenwalde, Germany) revealed elevated titers of antibodies to multiple adrenergic receptors along with muscarinic cholinergic receptors and angiotensin‐converting enzyme 2 (ACE2) (Table 1).

See full text here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9537871/