Evaluation of inflammatory markers in the diagnosis, differential diagnosis, and prognosis of pulmonary sarcoidosis

Aims: Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), systemic immune-inflammation index (SII), C-reactive protein-to-albumin ratio (CAR), and prognostic nutritional index (PNI) are practical and readily available laboratory markers that provide valuable information regarding the diagnosis, disease severity, and prognosis of various inflammatory conditions. This study aimed to evaluate the diagnostic and prognostic utility of these inflammatory indices (NLR, PLR, LMR, SII, CAR, and PNI) in patients with pulmonary sarcoidosis. Methods: This retrospective study included 107 patients diagnosed with sarcoidosis and 103 healthy control subjects who were evaluated at Şişli Etfal Training and Research Hospital between November 15, 2019, and November 15, 2024. Demographic characteristics, radiological findings, disease stages, and baseline laboratory parameters-including neutrophil, lymphocyte, platelet counts, C-reactive protein, and albumin levels-were recorded. The inflammatory indices were calculated, and statistical and regression analyses were performed to assess their diagnostic and prognostic significance. Results: The study population consisted of 107 patients with pulmonary sarcoidosis and 103 healthy controls. A statistically significant difference in PNI values was observed among different disease stages in the patient group (F=7.099, p