Use of pleural cryobiopsy for tissue culture specimens: a case report

A 43-year-old man presented with cough. His chest X-ray showed a left-sided pleural effusion. We suspected tuberculous pleurisy (TP), and thoracoscopy under local anaesthesia was performed. It showed entire pleura with scattered nodules. Nodules were biopsied by conventional biopsy forceps, but the tissue sample was small. Therefore, the nodules were biopsied with a cryoprobe. The tissue size obtained was 2 mm by conventional biopsy forceps, and 6 mm at 5 sec by cryobiopsy. Histological analysis of the conventional biopsy forceps and cryobiopsy specimen showed inflammation with lymphocytes and caseating granulomas. Tissue culture of conventional biopsy forceps was positive for Mycobacterium tuberculosis, and all sensitivity tests were positive. But, the tissue culture of the cryobiopsy sample was negative. There is a possibility that cryobiopsy is not useful for tissue culture for TP.