Diagnostic Utility of Bronchoalveolar Lavage in Patients with Acute Leukemia under Broad-Spectrum Anti-Infective Treatment

The Differential Diagnostic Value of Chest Computed Tomography for the Identification of Pathogens Causing Pulmonary Infections in Patients with Hematological Malignancies

Objective

The role of chest computed tomography (CT) in distinguishing the causative pathogens of pulmonary infections in patients with hematological malignancies (HM) is unclear. The aim of our study was to compare and assess the clinical characteristics, radiologic features and potential differential diagnostic value of CT in HM patients and other different immune statuses patients with pulmonary infections.

Methods

Patients were divided into immunocompetent (105 cases) and immunocompromised groups (99 cases) according to immune status. Immunocompromised patients included the HM group (63 cases) and the non-HM group (42 cases). The basic clinical data and CT findings were collected and statistically analyzed.

Results

Regarding the pathogen distribution, viral, Pneumocystis jirovecii and mixed infections were more common in the immunocompromised group than the immunocompetent (p < 0.01), but viral infections were more common in the HM group than in the non-HM group (p=0.013). Immunocompromised patients had more diverse CT findings and more serious lesions (mostly graded 2-4) than immunocompetent patients. The most common CT findings in HM patients were consolidation and ground-glass opacities (GGO), which were also found in the non-HM group. The overall diagnostic accuracy of CT was lower in immunocompromised patients than in immunocompetent patients (25.7% vs 50.5%, p< 0.01). CT had better diagnostic efficacy for fungi and Pneumocystis jirovecii in HM patients.

Conclusion

CT diagnosis is less efficient in distinguishing the causative pathogens of HM patients. However, CT can help distinguish fungal pneumonia and Pneumocystis jirovecii pneumonia in HM patients.

Clinical Relevance Statement

Our study might facilitate clinical decision-making in fungal pneumonia and Pneumocystis jirovecii pneumonia in HM patients.

A Single-Center Study of the Utility of Bronchoalveolar Lavage in Critically Ill Patients With Haematological Malignancy or Stem Cell Transplants

INTRODUCTION

The aim of this study was to evaluate the yield of bronchoscopy-guided bronchoalveolar lavage (BAL) and decisions on management of antimicrobials in critically ill patients with hematological malignancy and/or hematological stem cell transplant (HSCT). The safety and tolerance of bronchoscopy were also reported.

METHODS

A retrospective cohort study was conducted by reviewing health charts of all adult patients with a hematological malignancy and/or an HSCT who were admitted to the intensive care unit and underwent bronchoscopy and BAL over four years from April 2016 to April 2020 at King Abdulaziz Medical City, Riyadh.  Results: The cohort included 75 critically ill patients. Of these 75 patients, 53 (70.7%) had HSCT (allogenic 66%, autologous 32.1%, haplogenic 3.8%). Computed tomography of the chest was abnormal in all patients. Predominant findings included airspace abnormalities, ground glass opacities, and others. The positive yield was found to be 20% for bacterial, 22% for viral, 21% for fungal, and other organisms were identified in 2%. Although cytology was not performed in 18 patients, malignant cells were identified on BAL in two patients. While the overall mortality of the cohort was high (46.7%), the vast majority (94.7%) tolerated bronchoscopy and BAL without any complications. However, three patients (4%) developed a pneumothorax and one patient bled and developed the acute respiratory distress syndrome post bronchoscopy.

CONCLUSIONS

BAL can identify and detect microorganisms directly influencing the clinical care of patients who have received non-invasive diagnostic tests that yielded negative culture results. Bronchoscopy and BAL are generally safe and well tolerated by critically ill patients with hematological malignancy or HSCT.