Prevalence and outcomes of SARS-CoV-2 infection in ILD: Post-pandemic study in South Italy

Antonio  Russo; Luigi Massari; Gaetano  Rea; Stefano  Sanduzzi Zamparelli; Ludovica  Capitelli; Fausto  De Michele; Marialuisa Bocchino

doi:10.5826/mrm.2026.1052

Prevalence and outcomes of SARS-CoV-2 infection in ILD: Post-pandemic study in South Italy

Authors

Antonio Russo UOC Pneumologia e Fisiopatologia Respiratoria, AORN Cardarelli, Napoli
Luigi Massari UOC Pneumotisiologia, Dipartimento di Medicina Clinica e Chirurgia, Università degli Studi Federico II, Napoli
Gaetano Rea Dipartimento di Radiologia, Azienda Ospedaliera dei Colli, Napoli
Stefano Sanduzzi Zamparelli UOC Pneumologia e Fisiopatologia Respiratoria, AORN Cardarelli, Napoli
Ludovica Capitelli UOC Pneumologia e Fisiopatologia Respiratoria, AORN Cardarelli, Napoli
Fausto De Michele UOC Pneumologia e Fisiopatologia Respiratoria, AORN Cardarelli, Napoli
Marialuisa Bocchino UOC Pneumotisiologia, Dipartimento di Medicina Clinica e Chirurgia, Università degli Studi Federico II, Napoli

DOI: https://doi.org/10.5826/mrm.2026.1052

Keywords:

SARS-CoV-2, Interstitial Lung Disease, Pulmonary Fibrosis

Abstract

This retrospective study assessed the impact of SARS-CoV-2 infection on patients with interstitial lung disease (ILD) at two tertiary centers in Southern Italy between January 2022 and December 2023. The cohort included 282 ILD patients (mean age 69.6 years; 54.9% male), with common diagnoses such as idiopathic pulmonary fibrosis (33.3%) and connective tissue disease-associated ILD (18.7%). SARS-CoV-2 infection occurred in 130 patients (46%), mostly with mild or asymptomatic cases. Pneumonia developed in 18 cases, with 72.2% requiring hospitalization and 5 COVID-19-related deaths. Patients with pneumonia had higher rates of ILD progression (27.7%) and incidental post-infection ILD diagnoses (22.2%) than those with mild infection. Vaccination rates were high, correlating with favorable outcomes in most cases. Importantly, pneumonia cases were often associated with incomplete vaccination or complex comorbidities. Differentiating COVID-19-related lung changes from ILD progression proved challenging, highlighting the importance of specialized radiologic assessment. Excluding COVID-related deaths, mortality rates were similar regardless of infection status, suggesting a degree of resilience among ILD patients. The study concludes that with high vaccine coverage and careful follow-up, most ILD patients had stable outcomes after SARS-CoV-2 infection. However, pneumonia remains a risk factor for adverse outcomes, underscoring the need for long-term, specialized ILD care.

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