This paper presents a case of a young patient with cyanosis and digital clubbing, until then an active, sporty person. He sought medical assistance due to the growing dyspnoea and the drop of effort tolerance. Initially the diagnostic process focused on the confirmation of the suspicion of pulmonary fibrosis or another interstitial lung disease as causes of the respiratory failure. Due to the atypical presentation of the symptoms, reaching the final diagnosis of digestive system disease with lung involvement required a more thorough multifaceted diagnostics of a number of systems and organs.