Characterization of patients with idiopathic interstitial pulmonary disease and capillary and laboratory findings in two health institutions in Medellín, Colombia: A descriptive study

Introduction: Interstitial lung disease (ILD) usually has a poor therapeutic response and prognosis. One of the methods that could help in the diagnosis and optimize the management of these patients is capillaroscopy. The study aimed to determine the clinical and capillaroscopic characteristics of patients with ILD and the frequency of findings suggestive of autoimmune disease. Materials and methods: A descriptive observational study that evaluated patients with ILD treated between 2010 and 2019 without a previous diagnosis of autoimmune disease. An interview, capillaroscopy, and a laboratory tests were performed. Results: 28 patients were evaluated, 16 (57.1%) were women and 17 (60.7%) had hypertension. Three patients (10.7%) reported morning stiffness for more than 60 minutes and there was one unexplained digital oedema. There were no telangiectasias, Raynaud's phenomenon, mechanic's hands, sclerodactyly or Gottron's sign, or ANAs titres greater than 1:80. The rest of the laboratory tests were negative in 100% of the patients. In the capillaroscopies, 13 (46.4%) patients had a normal capillaroscopic pattern and 15 (53.6%) had capillaroscopic abnormalities of undetermined significance. There were none with a pattern of systemic sclerosis or similar. Conclusions: No laboratory or capillaroscopy findings were found that suggested interstitial disease with autoimmune features, possibly due to the low prevalence of the disease, its high mortality, and underdiagnosis. These findings reinforce the concept of capillaroscopic normality in patients with non-autoimmune ILD and call for an active search for ILD with autoimmune features for prognostic purposes.