Pleural effusions are still representing a challenge in daily practice.
Materials and methods: This retrospective study on 221 patients with pleurisies hospitalized in our unit is focused on the contribution of different types of pleural fluid morphological evaluation in setting a correct etiological diagnosis. The algorithm of investigation included: gross aspects assessment on X-ray records and by direct observation of pleural liquid obtained by thoracentesis and microscopic assessment on cytology slides of pleural fluid and on histopathological samples obtained by pleural needle biopsies.
Results: Mycobacterial etiology was the most frequent, with 72% of all cases, followed by tumoral etiology. Cytologic examination of pleural fluid was useful in establishing the final diagnosis in 66.1% of cases, histopathological assessment being imposed for the rest of cases.
Discussion: Imagistic investigation offered appropriate information concerning the site and extention of pleural effusions and guided, in certain cases, the needle biopsy. Gross aspect of pleural fluid oriented quite well the suspicion diagnosis. The use of a set of cytological "formulas" was useful in filtering subsequently the suspicion diagnosis. Histopatholgical examination of pleural tissue samples established the final diagnosis in cases where etiology was still uncertain after laboratory and cytological examination and subtyped further the pathologic processes within each main category of etiology.
Conclusions: A correct diagnosis of pleural effusions could be achieved only by going through a precise algorithm of investigation where, besides thorough clinical examination and laboratory tests especially of pleural liquid, morphological assessment and in particular cytologic examination of pleural liquid and histopatological examination of pleural tissue samples are essential.