Efforts to control viral transmission began shortly after the first cases of coronavirus infection 2019 were identified (COVID-19). Initial efforts were related to contact precautions, hand hygiene, and the use of masks; however, it soon became apparent that a robust global immunization boost was the most effective way to curb disease transmission. In the United States, the first doses of COVID-19 vaccine were released shortly after the FDA granted emergency use of the coronavirus 2 (SARS-CoV-2) syndrome vaccine. severe acute respiratory. What this also meant was that many of the routine phases that any new drug or vaccine goes through before being publicly released were avoided. Over the past two years, several side effects and reactions have been observed following the administration of the COVID-19 vaccine, the most common being local events at the injection site (eg, pain, redness, swelling). ) and systemic effects (e.g., fatigue, headaches, myalgias). . We report the case of a 64-year-old woman who developed bilateral numbness and tingling in her lower extremities a few weeks after receiving the third dose of the Modern SARS-CoV-2 vaccine. The patient underwent extensive testing to verify the diagnosis. He had negative autonomic tests and normal nerve conduction (EMG) study / electromyography, which did not reveal large fiber neuropathy. Finally, the patient underwent a skin biopsy, which revealed a small fiber neuropathy. This case report highlights the importance of maintaining a broad differential for rare side effects, such as small fiber neuropathy, which are currently being observed and reported in the literature.
Introduction
Some studies indicate vaccine acceptance rates as low as 56.9% in the general population of the United States (USA) [1]. Vaccines usually result in part from a lack of confidence in the safety of vaccination and concern about side effects. [2]. Several side effects related to coronavirus disease vaccines 2019 (COVID-19) have been reported in the last two years. Neurological side effects are mainly limited to reports of demyelinating diseases, thrombotic events, and convulsive threshold reduction due to febrile episodes. [3]. Although small fiber neuropathy is usually associated with diabetes mellitus, amyloidosis, and toxins to name a few predisposing factors, we report the case of an elderly woman who developed biopsy-tested small fiber neuropathy after receiving the booster dose of Moderna SARS-CoV-2. vaccine [4].
Presentation of the case
64-year-old woman with significant medical history of vertigo, positive antinuclear antibodies (ANA), suspected undifferentiated connective tissue disease, hyper IgE syndrome, borderline diabetes mellitus (not in any treatment) and basal cell cancer presented in patient. Emergency service with complaints of a day of chest discomfort, palpitations and contractions and tingling in the left leg.
The patient was in her usual state of health until she developed new symptoms, such as dull back pain, palpitations, dizziness, and tingling in the lower extremities. This was approximately three weeks after receiving the third dose of Modern Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) vaccine. The patient described her symptoms as a paroxysmal tingling that mainly affected the feet, L> R. The patient denied back pain, focal weakness, gait changes, or falls. He denied the rash or loss of muscle mass. He had been referred to the emergency department for concern about deep vein thrombosis; however, the Doppler ultrasound that was done was negative. All vital signs were within normal limits, the ECG showed a normal sinus rhythm with a nonspecific T-wave abnormality, and the chest x-ray showed no acute pathology. Thyroid stimulating hormone (TSH) was within normal limits. The patient was asked to stay hydrated for the next few days and to reduce physical activity, and was discharged from the SU. The following week, the patient continued with cardiology and was placed on a Holter monitor, which revealed only one event of four heartbeat ventricular tachycardia under review.
Her complaints of tingling and numbness in her lower extremities were persistent and the patient was followed up with Neurology. He underwent further study for neuropathy and palpitations. Autonomous tests were performed, which did not reveal any evidence of parasympathetic cardiovascular dysfunction, adrenergic dysfunction, postural orthostatic tachycardia syndrome (POTS), small fiber neuropathy, or orthostatic hypotension. Nerve conduction (EMG) study / electromyography did not reveal large fiber neuropathy. Finally, the patient underwent a skin biopsy to further assess small fiber neuropathy. Samples of the distal leg and proximal thigh were consistent with a length-dependent mild neuropathy affecting nonmyelinated sensory fibers, while specimens of the left ankle revealed occasional small axonal swellings in the epidermis and subepidermis.
Discussion
Since the onset of the COVID-19 pandemic, there has been a global collaborative effort to develop effective vaccines. Due to the prioritization of early vaccination deployment, the side effects of these vaccines have not been studied in detail. [5].
The magnitude of COVID-19 vaccines is immense. According to the World Health Organization, 65.7% of the world’s population has received at least one dose of a vaccine against COVID-19 and up to six million doses are administered daily. Given the rapid development of COVID-19 vaccines and the number of COVID-19 vaccines administered, it is essential to report and study side effects worldwide. [6].
In the last two years, several articles have been published describing various neurological complications following the administration of the COVID-19 vaccine. Finsterer et al. reviewed the current literature and found that the four most commonly reported neurological side effects in order of incidence are: headache, Guillain Barre syndrome, venous sinus thrombosis, and transverse myelitis. [7]. The fact that these neurological side effects occur after the administration of the vaccine supports a causal relationship between these vaccines and the neurological complications. On the other hand, the relatively small number of cases reported with neurological side effects shows that the risk of the vaccine may be minimal. [8]. However, it is the ethical duty of every healthcare provider to report any suspected side effects of the vaccine.
We conducted an extensive literature review to find cases of small fiber neuropathy and vaccination against COVID-19. One study reported a 43-year-old man with a history of neurosarcoidosis and small fiber neuropathy. Three days after her first dose, she had an outbreak of her underlying neurological disease. He recovered in two weeks and was able to receive his second dose [9]. A case report published in July 2021 described a 57-year-old woman showing symptoms compatible with small fiber neuropathy one week after her second vaccination. He reported resolution of his symptoms within two weeks [10]. The previous two cases involved the use of the Pfizer vaccine. We have not been able to find such a report with the vaccine of the Modern National Institute of Allergy and Infectious Diseases (NIAID).
To understand the potential relationship between small fiber neuropathy and COVID-19 vaccinations, it is important to appreciate the pathophysiology of the disease. Autoantibodies are more likely to target neuronal proteins, leading to small fiber neuropathy. [11]. A study published in April 2022 showed that there is a transient increase in autoantibodies during COVID-19 infection, which could be due to T and B cell activation through the recognition of viral epitopes by molecular mimicry. [12]. Thus, it can be hypothesized that vaccination may cause an increase in autoantibodies, through molecular mimicry, which can lead to small fiber neuropathy. However, a study in the United Kingdom has shown that there is no significant structural similarity between the genetic or linear structure of the SARS-CoV-2 protein and the structure of the human peripheral nerve tissue protein, which makes molecular mimicry unlikely. Despite this finding, the authors stated that they cannot rule out the possibility that post-translational modification of viral proteins could theoretically lead to some sort of immune similarity. [13].
Moderna’s mRNA vaccine has more reports of mild side effects such as myalgia and nausea compared to its Pfizer counterpart. [14]. There is a paucity of data on the serious side effects of the Modern vaccine. COVID-19 vaccine-related side effects require long-term monitoring and reporting; however, it may be reasonable to take a prudently optimistic approach to vaccine administration.
Conclusions
The emergency deployment of COVID-19 vaccines has meant that many of the short- and long-term side effects of vaccines will only become apparent in the coming years. In the meantime, it is imperative that even infrequent phenomena be reported so that patients and providers can make more informed and individualized decisions about vaccine safety. Small fiber neuropathy is often difficult to manage due to the inability to determine predisposing factors. In the future, if more cases of this type occur in connection with the administration of the COVID-19 vaccine followed by the development of small fiber neuropathy, prospective studies will be needed to establish causation.