Ricerca micobatterica con TBNA nelle linfoadenopatie mediastiniche con aspetto necrotico colliquativo

Aim. The trans bronchial needle aspiration (TBNA) is a minimally invasive technique that allows the collection of biological samples from lymphnodes in the hilar-mediastinal district. This method greatly expands the potential of bronchoscopy. TBNA is inserted fully in the differential diagnosis of mediastinal isolate lesions. Methods. In 2013 we examined 14 patients, 12 males and 2 females, aged 45 to 83 years, with hilar-mediastinal necrotic and colliquative lymphadenopathy. All patients, prior to CT/PET scans, were submitted to bronchoscopy 'with TBNA of involved lymphnode stations, and in all cases specimens were processed for cytological and microbiological investigations, performing post-washing procedure of the TBNA catheter for detection of mycobacteria. Results. Microbiological tests on 14 samples showed in 1 case positivity for Mycobacterium tuberculosis complex (MTC) with sensitivity to rifampicin at Xpert MTB-RIF test (direct gene amplification); the rapid microbiological diagnosis was confirmed by a positive culture at 34 days with the identification and susceptibility testing set up on the same crop. The remaining 13 samples were negative for mycobacteria and alternative final diagnosis was obtained with TBNA or other steps. Conclusion. TBNA is a minimally invasive technique called "medical mediastinoscopy" that should be used in place of mediastinoscopy in diagnostic cases, and should be considered complementary to mediastinoscopy in non diagnostic cases. In our experience, in order to obtain the diagnosis, in mediastinal lymphadenopathy with necrotic colliquative characteristics, it is useful to perform cytological and microbiological investigation on material obtained from TBNA.