Drug-induced interstitial lung disease: Insights from a Tunisian case series and literature review

Abstract

Introduction: Drug-induced lung disease (DILD) can affect various lung structures, with interstitial lung disease (ILD) being the most common manifestation. Drug-induced ILD (DI-ILD) represents a heterogeneous group of conditions with varying degrees of severity. Over 400 drugs are implicated in causing ILD, with diagnosis often challenging due to nonspecific clinical, radiological, and histological findings. Methods: We conducted a retrospective descriptive study over a 10-year period that included all cases of DI-ILD notified to the National Pharmacovigilance Center. Data collection included demographics, clinical history, CT findings, and further investigations. Results: A total of 20 cases involving 14 drugs were analyzed. Patients had a median age of 59.9 years, with a slight female predominance. Underlying lung conditions and COVID-19 infection were noted in some cases. Respiratory symptoms typically developed after one year of drug use, with most cases presenting with mild symptoms (cough and dyspnea). CT findings varied across cases, with nonspecific interstitial pneumonia (NSIP) being the most common pattern. Methotrexate was the most frequently implicated drug. In some cases, the causative drug was discontinued, leading to clinical improvement, while other cases experienced persistent or worsened symptoms. Conclusion: DI-ILD represents a highly heterogeneous group of conditions with an expanding list of potential triggers. Establishing a definitive causal relationship remains challenging and requires thorough investigation. The main conclusion is that DI-ILD remains severely underreported in Tunisia, as in many other countries, and that patients suspected of having this condition often do not undergo appropriate clinical diagnostic procedures to confirm the diagnosis.