Beyond Cold Fingers—Secondary Raynaud\'s Phenomenon Revealing UCTD-associated Interstitial Lung Disease in a Young Male: A Case Report

REPORTlung bases.Cardiovascular and abdominal examinations were unremarkable. InvestIgatIonsDoppler studies showed normal upper and lower limb arterial flow.ANA was positive (+++) at 1:640; anti-Ro and U1RNP antibodies were positive.Nailfold capillaroscopy demonstrated giant, dilated, and irregular capillaries (Fig. 1C).Chest radiograph and high-resolution computed tomography (HRCT) revealed bilateral reticular opacities, with a nonspecific interstitial IntroductIonRaynaud's phenomenon (RP) is a common vasospastic disorder affecting 3-5% of the general population, characterized by triphasic color changes of pallor, cyanosis, and rubor in the digits. 1 While often benign and idiopathic (primary RP), it may also occur secondary to systemic autoimmune conditions such as systemic sclerosis, systemic lupus erythematosus, or undifferentiated connective tissue disease (UCTD). 2 Secondary RP is more likely to be associated with digital ulcerations, abnormal nailfold capillaries, and positive autoimmune serology, often signifying underlying systemic disease.Early recognition of secondary RP is crucial, as it can herald progressive complications, including interstitial lung disease (ILD), pulmonary hypertension, and digital gangrene.We present a case of a young nonsmoker male with RP, digital ulcers, and interstitial lung involvement, subsequently diagnosed as UCTD-ILD.