The significance of non-specific pleuritis: a single-center experience

F. Porcarelli*^a (Dr), F. Mei^a (Dr), L. Zuccatosta^b (Dr), M. Bonifazi^a (Prof), S. Gasparini^a (Prof)

^a Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, ITALY ; ^b Pulmonary Diseases Unit, Azienda Ospedaliera Universitaria Ospedali Riuniti, Ancona, ITALY

* francesco93.porcarelli@gmail.com

Background

Non-specific pleuritis (NSP) is a broad term that describes chronic pleural inflammation without specific etiology. Various conditions may lead to this histological finding, posing a diagnostic challenge for clinicians, as a significant proportion of patients develop a malignant diagnosis, being mesothelioma the commonest. The aim of the study is to assess the long-term outcome of patients with NSP focusing on 'false negative' cases.

Methods

We retrospectively collected data from patients admitted to our Pulmonology Unit - Ospedali Riuniti (Ancona, Italy) from January 2015 to December 2021 for undiagnosed pleural effusion who underwent medical thoracoscopy (MT). We selected patients with histological diagnosis of NSP. Patients with alternative diagnosis were excluded. Follow up included visit, thoracic ultrasound scanning and, if needed, imaging.

Results

Out of a total of 393 thoracoscopies, 83 patients had the histological diagnosis of NSP. Mean follow-up time was 28,5 months. After a first diagnosis of NSP, 10 patients received a subsequent diagnosis of specific benign conditions (i.e. infection, drugs, autoimmunity) and 6 (7%) patients received diagnosis of pleural malignancy, most of them (85%) were mesothelioma. All malignancies were diagnosed within first 12 months. Remaining 67 patients (81%) were deemed as affected by idiopathic pleuritis and all of them followed truly benign evolution.

Conclusions

Our findings are largely in line with the established body of literature, confirming good prognosis in the majority of cases with histological diagnosis of NSP. The data underline the need of a close and prolonged follow-up in these patients, in order to detect a not negligible rate of malignancy.

Disclosure of funding source(s): none