[Difficult pneumonological diagnoses. I. Diagnoses that have not been established].
The authors show that the medical pneumologic practice meets cases in which, after the accumulation and interpretation of the clinical and paraclinical investigation results and after leaving aside the sets of the improbable, no certain diagnosis can be established. The possible reasons of this failure are: the physician's lack of experience in a radiographic chapter, lack of endowment of that medical unit, patient's refusal to be examined or the atypical evolution of the disease. The authors present two such cases, in which, due to the above-mentioned reasons, no certain diagnosis could be established.