Diagnóstico diferencial en pacientes con granulomas en biopsias de pulmón, pleura y/o ganglios mediastínicos del Instituto Nacional del Tórax

Abstract

Granulomatous diseases comprise a wide range of pathologies. However, in clinical practice, many pulmonary granulomas remain without etiology after the histologic examination. Our aim was to determine from the biopsies of the lung, pleura and mediastinal lymph nodes in which granulomas were reported, the clinical characteristics and diagnoses of the patients. Methodology: We analyzed retrospectively biopsies of the lung, pleura and mediastinal lymph nodes with granulomas from 75 patients handled at our institution (2012-2016), as well as their clinical and laboratory data. The information was obtained from medical records. A one-year mortality date was obtained from the civil registry. Main results: A cause was determined in all the cases, except in three of them (4%). The most frequent diagnoses were tuberculosis (n =37; 49%) and arcoidosis (n =18; 24%). Other causes were silicosis (5.3%), vasculitis (4%) and hypersensitivity pneumonitis (2.7%). Patients with tuberculosis (TB) had higher inflammatory parameters such as erythrocyte sedimentation rate and C-reactive protein. Besides granulomas with caseous necrosis were only found in TB patients. Instead, patients with sarcoidosis had skin lesions and a higher frequency of lymphadenopathy. Four patients (5.3%) died in a one-year of follow-up: two of them because of pneumonia and the other two patients because of chronic hypersensitivity and TB respectively.  Conclusion: Tuberculosis and sarcoidosis were the most common causes of respiratory granulomas in this retrospective study. A specific cause was determined in 96% of cases, considering clinical, laboratory and histopathological variables to do a right differential diagnosis.