Swyer-James-MacLeod Syndrome (SJMS) occurs as a result of childhood bronchiolitis obliterans. Typically, this disorder is diagnosed in childhood after evaluations for recurrent respiratory infections. One of the reasons to explain the difficulty in diagnosis is that when patients develop little bronchiectasis, and therefore, few symptoms, then this syndrome may not be recognized until adulthood. There are few references of the disease in children sowe think your description is interesting, we present the case of a 4 year old patient with acute respiratory symptoms of pneumonia, high lighting the most important aspects of clinical diagnosis today.