<h3>Background</h3> Interstitial lung disease (ILD) occurring in a person with a known or classifiable connective tissue disease (CTD) is referred as CTD-ILD. Approximately 15% of ILDs will have a background CTD. The presence of ILD is the primary determinant of prognosis. High-resolution CT (HRCT) is the diagnostic image of choice. Interstitial involvement can have different patterns, with nonspecific interstitial pneumonia (NSIP) being the most frequent. CTD-ILD is a challenging entity and its approach requires multidisciplinary teams (MDT). <h3>Objectives</h3> To describe clinical, serological, and radiological characteristics of patients who present with CTD-ILD at a reference ILD center in Colombia between 2021 and 2022 <h3>Methods</h3> A descriptive study of patients with ILD diagnosed by HCTR who have a confirmed autoimmune disease or at least one autoimmune feature, clinical or serological. Every case was evaluated by our MDT composed by pulmonologists, radiologists, rheumatologists, and pathologists. We developed an ILD registry from our inpatient and outpatient ILD-clinic between 2021 and 2022. The continuous variables were described as the mean and standard deviation, and nominal variables were evaluated based on frecuencies and percentages. All analysis were done in statistical package for the social sciences (SPSS) v. 21.0. <h3>Results</h3> Forty patients with ILD were included; 57% were hospitalized, and 65% were women. The majority of patients with ILD were diagnosed as interstitial pneumonia with autoimmune features (IPAF, 30%), followed by multiple autoimmune syndromes (22,5%), rheumatoid arthritis (15%) and primary Sjogren's syndrome (12,5%). The most common radiologic pattern was usual interstitial pneumonia (40%), followed by fibrotic NSIP (22.5%). The most common clinical finding where lung crackles (61,5%), sicca symptoms (57,5%) and arthritis (30%). Mean CVF in L(%) was 173 ± 89,8(72,6±27,2) and mean DLCO(%)52,6 ± 21. Progressive pulmonary fibrosis was frequent (20%), and 12.5% received antifibrotic therapy. Our mortality rate related to ILD was 21.7%. <h3>Conclusion</h3> In our 1-year cohort, we found that IPAF was the most prevalent CTD-ILD, followed by multiple autoimmune syndromes. The most common radiologic pattern overall was UIP, followed by fibrotic NSIP. CTD-ILD had a high mortality rate. Most of these cases were related to ILD. Our results highlight the importance of early disease detection and early therapeutic interventions. Treatment decisions must be individualized, and the risk of disease progression must be considered. <h3>References</h3> [1]Sambataro D, Sambataro G, Pignataro F, Zanframundo G, Codullo V, Fagone E, et al. Patients with Interstitial Lung Disease secondary to autoimmune diseases: How to recognize them? Diagnostics (Basel). 2020;10(4):208. [2]Kondoh Y, Makino S, Ogura T, et al. 2020 guide for the diagnosis and treatment of interstitial lung disease associated with connective tissue disease. <i>Respir Investig</i>. 2021;59(6):709-740. <h3>Acknowledgements</h3> Hospital Universitario San Ignacio - Interstitial lung disease multidisciplinary team. <h3>Disclosure of Interests</h3> Camila Borda Samper: None declared, Juan Sebastian Sierra: None declared, Daniel G. Fernández-Ávila Speakers bureau: yes, Carlos Celis Preciado: None declared, Maria Díaz Speakers bureau: yes.