SESSION TITLE: Chest Infections I Student/Resident Case Report Posters
SESSION TYPE: Student/Resident Case Report Poster
PRESENTED ON: Tuesday, October 27, 2015 at 01:30 PM - 02:30 PM
INTRODUCTION: A patient presenting with acute diffuse parenchymal lung disease was evaluated with fibered confocal fluorescence microscopy (FCFM) to obtain in vivo optical biopsies.
CASE PRESENTATION: 23-year-old, HIV-positive male presented with shortness of breath and fever for 5 days. He was an active smoker. There was tachycardia, tachypnea, hypoxia and oral thrush. Blood investigations showed mild anemia. Chest X-Ray and CT-chest (Figure 1) revealed bilateral diffuse alveolar infiltrates. Flexible bronchoscopy under moderate sedation and bronchoalveolar lavage was performed for microbiological analysis to evaluate pneumonia in an immunocompromised host. This revealed Pneumocystis jirovecii, alveolar macrophages and frothy aggregates. Patient was treated with trimethoprim and sulfamethoxazole with complete therapeutic response. FCFM was used to obtain optical biopsies from multiple bronchopulmonary segments before bronchoalveolar lavage using a 1.4 mm flexible miniprobe (Cellvizio, Mauna Kea Technologies, Paris, France). The images showed autofluorescent structures (32.8±7.9μm, n=20) in the alveolar spaces consistent with macrophages that were retaining tobacco tar . In addition, larger distinct structures (217.6±62.4μm, n=7) were seen that was consistent with the frothy aggregates obtained in the bronchoalveolar lavage. Deteriorated alveolar fibers in excess of what was consistent with miniprobe trauma were also detected.
DISCUSSION: FCFM showed homogenous involvement of all examined segments that was in contrast to the radiology findings, but was consistent with the patient’s clinical presentation. This finding confirms previous data that FCFM is more sensitive than CT . Other differentials for frothy aggregates are pulmonary alveolar proteinosis, pulmonary amyloidosis and lysed red blood cells . Optical biopsies may make it unnecessary to perform bronchoalveolar lavage if such findings can be confirmed and consequently reduce the risk of procedure related complications such as hypoxia and fever. Further studies are needed to confirm this finding and to assess the diagnostic sensitivity of FCFM.
CONCLUSIONS: FCFM may be useful in the diagnosis of diffuse parenchymal lung diseases such as pneumocystis pneumonia.
Reference #1: Thiberville, L., Salaün, M., Lachkar, S., Dominique, S., Moreno-Swirc, S., Vever-Bizet, C., & Bourg-Heckly, G. (2009). Human in vivo fluorescence microimaging of the alveolar ducts and sacs during bronchoscopy. European Respiratory Journal, 33(5), 974-985
Reference #2: Danilevskaya, O., Averyanov, A., Lesnyak, V., Chernyaev, A., & Sorokina, A. (2015). Confocal Laser Endomicroscopy for Diagnosis and Monitoring of Pulmonary Alveolar Proteinosis. Journal of bronchology & interventional pulmonology, 22(1), 33-40
Reference #3: Kini, S. R. (2002). Nonneoplastic lesions. Color atlas of pulmonary cytopathology (pp.69-71). Springer Science & Business Media.
DISCLOSURE: The following authors have nothing to disclose: Peng Meng, Gan Liang Tan, Su Ying Low, Angela Takano, Yuen Li Ng, Devanand Anantham
Fibered confocal fluorescence microscopy (FCFM) is an imaging technique, which can visualize the in vivo lung tissues, upto alveolar cellular levels. It is using a point illumination and pinhole apparatus to block out of focus lights. This enables it to get high resolution images of thick biological materials. With the emerging technique of fiber based confocal microscopy, it has become small enough to visualize various body cavities such as gastrointestinal tract, bladder, and lung. FCFM has been most extensively used by gastroenterologist . In the first consensus report , FCFM is claimed to be non-inferior to standard biopsy for Barrettâs oesophagus. And it is recommended for detection of gastrointestinal malignancies and inflammatory bowel disease. First pioneered by Thiberville in 2009 , various research studies have been carried out to visualize respiratory tract , , . The results show that this technique has great potential in differentiation between malignant and benign lung lesions, identification of transplant rejection, detection of morphological changes due to DPLD conditions and real-time monitoring of patients in ICU. Currently, the elastin which is the endogenous fluorescence material and macrophages can be identified on confocal microscopy without staining or intravenous contrast. This study was using fibered confocal fluorescence microscopy called Cellvizio (Mauna Kea Technologies, Paris France). This machine utilizes a thin semi-flexible probe with a diameter of 1.4 mm, which is small enough to go through the working channel of a bronchoscope and advance into distal air space. And it can generate a field of view of 600 Ã 600 Âµm with a lateral resolution of 5Âµm under the illumination from a light source of 488nm wavelength.