COVID-19 Vaccine-Induced Severe Pneumonitis

"1 Introduction

We report a case of severe pneumonitis as an adverse event of COVID-19 vaccination. The patient recovered after steroid pulse therapy...

2 Case Report

A 77-year-old male ex-smoker with a 30-pack-year history was admitted to our hospital with severe respiratory failure. He had no history of chronic interstitial lung disease and allergies. He had received his third dose of the COVID-19 vaccine (BNT162b2, Pfizer) 2 days prior. Computed tomography (CT) revealed multiple ground-glass opacities with traction bronchiectasis in both lungs...

3 Discussion

In this case, the patient developed severe pneumonitis following COVID-19 vaccination, and we evaluated cytokine dynamics during steroid therapy.

Analysis of circulating cytokines revealed markedly elevated IL-8, IL-6, and TNF-α levels. In contrast, IL-5, which plays a key role in allergic eosinophilic inflammation, was not elevated. However, the patient's IgE level was mildly elevated, suggesting a partial allergic response. Elevated IL-8 has been reported in IgE-mediated lung disease, supporting the possibility of an overlapping allergic component.

Meanwhile, IL-6 and IL-8 are also known mediators of systemic inflammation and cell-mediated immune activation. Therefore, we speculate that this patient exhibited a mixed immune reaction—both allergic and inflammatory...

Bergamaschi et al. reported that the second dose of BNT162b2 mRNA vaccine led to a sharp rise in cytokine levels, such as TNF-α and IL-6. Other studies have associated COVID-19 vaccination with autoimmune manifestations and cytokine release syndrome. Together, these findings suggest that vaccination can stimulate various immune pathways, potentially leading to allergic-like reactions and vaccine-related pneumonitis."