Background The granulomatous inflammatory response is a manifestation of many lung diseases.
Objective To evaluate the diagnostic value of epithelioid cell granulomas in bronchoscopic biopsies in daily clinical practice.
Methods The data of 105 patients with epithelioid cell granulomas in biopsy tissue who had undergone the bronchoscopic lung biopsy or bronchial biopsy at the Centre of Pulmonology and Allergology of Vilnius University Hospital Santariski klinikos (Vilnius, Lithuania) were examined. All cases were divided into non-necrotizing epithelioid cell granulomas and epithelioid cell granulomas with necrosis.
Results Of all the cases 66% had non-necrotizing epithelioid cell granulomas and 34% had epithelioid cell granulomas with necrosis. Without respect to the presence of necrosis in granulomas, the majority of the patients (79%) had sarcoidosis or tuberculosis; 94% of the patients with sarcoidosis had non-necrotizing epithelioid cell granulomas and the remaining 6% had granulomas with necrosis. The sensitivity of non-necrotizing epithelioid cell granuloma for the diagnosis of sarcoidosis was 94% and specificity 60%. The positive and negative predictive values were 68% and 92%, respectively.
Of the patients with tuberculosis 76% had epithelioid cell granulomas with necrosis and 24% had non-necrotizing epithelioid cell granulomas. The sensitivity of epithelioid cell granuloma with necrosis for the diagnosis of tuberculosis was 76% and specificity 85%. The positive and negative predictive values were 69%, and 88%, respectively.
Conclusion A significant overlap in types of granulomatous inflammation between tuberculosis and sarcoidosis was found. The type of epithelioid cell granuloma alone was not sufficient for the final clinical diagnosis.