The correlation between the diagnostic yield of bronchoalveolar lavage cellular analysis, clinical, pulmonary function and radiological findings in patients with newly diagnosed pulmonary sarcoidosis

Background
The lungs are the main organs affected by the systemic granulomatous disease sarcoidosis, which has an unclear etiology. Computerized tomography is now the mainstay for diagnosis and monitoring of pulmonary sarcoidosis. For diagnosis, bronchoalveolar lavage fluid (BALF) is useful since a ratio of cluster of differentiation 4 (CD4)/CD8 T cells greater than 3.5 is predictive of sarcoidosis.


Aim
Assess the relationship between the baseline clinical, spirometric, radiological characteristics and the BALF results in patients with newly diagnosed pulmonary sarcoidosis.


Patients and methods
This is a cross-sectional analytic study comprising 56 patients (aged >18 years) who had just been diagnosed with pulmonary sarcoidosis and were admitted to the Chest Department of Kasr Alainy Hospital at Cairo University. Spirometric tests using a flow-volume loop, high resolution computed tomography chest and bronchoalveolar lavage (cellular analysis and CD4/CD8 ratio) were performed.


Results
Based on the BALF analysis of all the 56 patients, the lymphocytic BAL was 89.3% and the mean CD4/CD8 was 3.3 ± 1.95 (0.65–9.43). The BALF and clinical data correlate well, with lymphocytic BAL being more strongly linked to dyspnea (93.6%) and cough (66.7%) than polymorphs BAL with P value 0.046.This alsoo related to spirometric data, where a lower forced expiratory volume in the first second (FEV1) (mean 66.8 ± 11.62) was linked to lymphocytic BAL compared with polymorphs BAL (mean 72.17 ± 3.97) with P value of 0.032. however, there is no correlation with radiological results.


Conclusion
The diagnosis of sarcoidosis is supported by BALF analysis but should not be considered diagnostic by itself. Clinical and spirometric results are correlated with it. However, there is no correlation with radiological results.