The place of the bronchoalveolar lavage in the diagnosis of interstitial lung disease: a descriptive and qualitative study.

BACKGROUND: Interstitial lung disease represents a challenge and consists in more than 200 entities. Their diagnoses are assessed through a multidisciplinary approach including pulmonologists, radiologists, pathologists and biologists. BAL analysis is useful mainly when clinical and radiological findings aren't suggestive of an etiology. Even if, the indication of BAL is consensual, its real place as a diagnostic mean remains non consensual. AIM: To describe the BAL findings and to analyse the perceptions of the pulmonologists, anaesthesiologists and pathologists implicated in the interpretation of the BAL data, that are related to the presentation and the validity of the results. METHODS: the authors performed a descriptive study about BAL results during an 8-year-period (2010-2018) and a qualitative study assessing the pulmonologists, anaesthesiologists and pathologists' opinions concerning the different results performed in the same institution. Two questionnaires were conceived with participation of different experts and satisfaction scores were calculated. RESULTS: 2508 BAL were recorded including 1320 women (53%) and 1188 men (47%) with a sex-ratio (H/F) of 0,9. The mean age of the patients was 51 years. The mean response delay was 3.25 days. An accurate diagnosis was retained in 24.3%. It consisted in infection evoked in 13.89% cases. Eosinophilic pneumonia was evoked in 0.35% cases. 15.01% cases presented erythrophagocytosis with a golde score>100 favouring active alveolar haemorrhage with occult alveolar haemorrhage. Lipoproteinosis was diagnosed in 2 cases. Adenocarcinoma was retained in 1.04% cases and lymphoma in 0.16% cases. Langerhans cell histiocytosis was confirmed in 1.51% cases. In the other cases, cellular profile was not specific evoking tuberculosis or sarcoidosis in 316 cases with a CD4/CD8 ratio superior to 1,6 and the diagnoses of tuberculosis or hypersensitivity pneumonia in 202 cases with a CD4/CD8 ratio inferior to 1,2. Concerning the questionnaire-based study, 50 pulmonologists and anaesthesiologists attributed a mean score of 7.96/10 (DS=0.55) concerning the presentation of the results and 9.28/15 (DS=0.77) concerning the quality and validity of the results. On the other hand, the mean satisfaction score rated by pathologists reached 24/40. CONCLUSION: BAL results could be helpful for the management of interstitial lung disease depending on the experience of pathologists and a good communication between pulmonologists, anaesthesiologists and pathologists.

[Which technique should be used in the phenotyping of lymphocytic alveolitis: Immunocytochemistry or flow cytometry]. / Quelle technique adopter pour le phénotypage des alvéolites lymphocytaires : immunocytochimie ou cytométrie en flux ?

BACKGROUND: Diffuse interstitial pneumonias are considered as a group of multiple affections characterized by challenging diagnoses because of the lack of specific clinical signs. Radiologic investigations highlight the diagnoses in most of the cases but bronchoalveolar lavage plays a key role in the diagnostic diagram. We aim to compare the immunocytochemical technique and the flow cytometry in the phenotyping of lymphocytic alveolitis. METHODS: We described a series of 32 lymphocytic alveolitis, which were analyzed using immunocytochemistry and flow cytometry. RESULTS: We found a good reproducibility between the immunocytochemistry performed on smears and cytoblocks (kappa=0.7) and a poor reproducibility between immunocytochemistry and flow cytometry (kappa=0.35). CONCLUSION: Our study emphasized on the poor reproducibility between immunocytochemistry and flow cytometry. Further studies about the reliability of both techniques are needed especially in discordant cases.

The diagnostic importance of the bronchoalveolar lavage in lymphocytic alveolitis.

Multidisciplinary concertation is mandatory in order to assess interstitial pneumonias. The study of the bronchoalveolar lavage helps evoking a diagnosis according to the lavage profile. In lymphocytic alveolitis, immunocytochemistry, or in flux cytometry are necessary in order to identify the different clusters of lymphocytes implicated. Our objective was to evaluate the profile of 31 lymphocytic alveolitis using 2 different techniques which are the immunocytochemistry and the in flow cytometry in order to evaluate the efficacy of each technique and to compare the different results to the final diagnoses. We describe a retrospective study about 31 patients admitted to our hospital in order to explore an interstitial pneumonia between January and July 2014. Bronchial endoscopy and bronchoalveolar lavage were performed in all cases. The sensitivity of the in flow cytometry was estimated to 53% and its specificity reached 33%. On the other hand, the immunocytochemistry presented a specificity of 42.8% and a sensitivity of 42.8%. The final diagnoses retained consisted in sarcoidosis in 12 cases, infectious pneumonia in 10 cases, hypersensitivity pneumonia in 3 cases, cryptogenic pneumonia in 3 cases, idiopathic fibrosis in 2 cases, and adenocarcinoma in 1 case. The relevance of both techniques depends on many factors. They necessitate an available material, well-trained technicians, and experimented pathologists.

Cytological smears and cell blocks on endobronchial aspirates complement each other and allow a higher diagnostic yield.

The accurate diagnosis of lung carcinoma has become compulsory especially after the introduction of new target therapies. Most of the patients are non operable. This fact points out the diagnostic importance of the cytology specimen. Our target was to assess the diagnostic efficacy of bronchial smears and cell blocks by comparing their results with those of the final diagnoses made on biopsies. We conducted a prospective study of 55 bronchial aspirates. It showed a sensitivity of 100% and a specificity of 100% when coupling both techniques. These results put emphasis on the diagnostic efficacy of both bronchial smears and cell blocks in diagnosing bronchial carcinoma.