Usefulness of Bronchoscopic Probe-Based Confocal Laser Endomicroscopy in the Diagnosis of <b><i>Pneumocystis jirovecii</i></b> Pneumonia

Abstract

Background: Probe-based confocal laser endomicroscopy (pCLE) is a novel technique that provides in vivo microscopic imaging of the distal lung. We hypothesized that the intra-alveolar exudates characterizing Pneumocystis jirovecii pneumonia (PJP) can be identified by pCLE in vivo and help in its diagnosis. Objectives: We aimed toassess the usefulness of pCLE for the in vivo diagnosis of PJP. Methods: Thirty-two human immunodeficiency virus (HIV)-positive patients with new pulmonary infiltrates and fever were studied using pCLE. Real-time alveolar images were recorded during the bronchoscopy for off-line analysis by two independent observers. Bronchoalveolar lavage samples were also obtained and processed for microbiology and cytological evaluation, including Grocott stain for P. jirovecii. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of pCLE for the diagnosis of PJP in these patients were calculated. Results: Fourteen patients (44%) were confirmed to have PJP by cultures/staining. pCLE was well tolerated in all patients. It identified intra-alveolar exudates in 13 of them (41%), where 11 of them (85%) had positive Grocott stain for P. jirovecci, with 93% concordance between observers. Sensitivity, specificity, PPV and NPV of pCLE for the diagnosis of PJP were 79, 89, 85 and 84%, respectively. In smokers, these figures improved to be 92, 88, 85 and 94%. Conclusions: pCLE is a quick and safe procedure for on-site diagnosis of PJP in HIV+ patients with excellent specificity and sensitivity mainly in smokers.

In vivo probe‐based confocal laser endomicroscopy in chronic interstitial lung diseases: Specific descriptors and correlation with chest CT

“…Bronchiolar and alveolar pCLE features of the normal lung have been described in a previous study on healthy volunteers (HV). Recently, the pCLE features of pulmonary alveolar proteinosis (PAP), amiodarone‐related ILD, Pneumocystis jirovecii infection, acute lung allograft rejection and other rare ILD have been reported . However, the interpretation of distal lung confocal images remains challenging, as imaging is mainly based, at least in non‐smoking subjects, on the elastin framework of the alveolar ducts and sacs …”

Bronchoscopic fibered confocal fluorescence microscopy for longitudinal in vivo assessment of pulmonary fungal infections in free-breathing mice

“…Previous clinical studies have shown that this approach can successfully be used to investigate the human airways and lungs based on autofluorescence originating from the elastin network 25 – 28 . To date, applications in the field of fungal lung infections have been limited because of a lack of specific signals originating from the pathogens 29 , 30 . One possible solution to solve the lack of specificity in WT infections is the in vivo use of fluorophores that specifically bind to fungal elements.…”

Interventional bronchoscopy in children: Planning the path ahead

“…techniques which are not as widely used include bronchial thermoplasty (primarily used in severe asthma) [15][16][17] and probe-based confocal laser endomicroscopy imaging of airways and alveoli (a new technique under development). [18][19][20] Like linear EBUS-TBNA and EUS-B-FNA all of the techniques that are widely used in adult practice, have the potential to be applied to pediatric practice. In fact many of them already are being used.…”

“…They can also be used for removal of foreign body as when the probe rapidly cools it attaches to the foreign body and then can retrieve it . Other techniques which are not as widely used include bronchial thermoplasty (primarily used in severe asthma) and probe‐based confocal laser endomicroscopy imaging of airways and alveoli (a new technique under development) …”