A new study found that bronchoalveolar lavage could help identify the cause of acute respiratory illness and guide treatment decision-making in most immunocompromised pediatric patients evaluated over 5 years.
The researchers reviewed 137 bronchoalveolar lavage (BAL) procedures performed on 108 pediatric patients with weakened immune systems. These patients had conditions such as leukemia, solid tumors, sickle cell disease, or had undergone stem cell transplants. Most of them were already receiving antimicrobial therapy, and more than half of them were in intensive care at the time of the procedure.
BAL identified at least one potential pathogen in 61% of cases, including viruses, fungi, and bacteria. In 17 cases, pathogens found by BAL weren't detected by other samples such as blood or upper airway swabs.
BAL results led to changes in antimicrobial management in 88% of cases. These changes included discontinuing or avoiding antibiotics when BAL results were negative or identified viruses without available treatments as well as adding medications when previously undetected pathogens were found.
“BAL results contributed to changes in antimicrobial management in 120 (87.6%) cases and contributed to the [acute respiratory illness] diagnosis in 106 (77.3%) cases,” said lead study author Afreen Abraham, of the Department of Infectious Diseases at St. Jude Children’s Research Hospital, and colleagues.
In 81 cases (approximately 60%), BAL results alone provided the basis for diagnosing the illness. These included both infectious causes such as pneumonia and noninfectious causes like alveolar hemorrhage or inflammation. Among patients with fungal infections, detection of molds or Pneumocystis jirovecii from BAL always matched the final diagnosis.
Pediatric patients who had undergone hematopoietic cell transplantation or had lung lesions described as nodules, consolidation, or interstitial infiltrates were more likely to have a positive BAL. In contrast, those with severe neutropenia had lower detection rates, but more than 40% still yielded pathogens.
The procedure was generally well tolerated. Among those not already intubated, only 3 patients required mechanical ventilation following BAL, and all of them were extubated within 48 hours. None of the patients required intensive care unit transfer as a result of the procedure.
The researchers also evaluated the use of metagenomic next-generation sequencing (mNGS) on BAL fluid. This method identified pathogens in nearly two-thirds of the tested cases, although its average turnaround time of 9 days limited immediate clinical use.
The researchers found that BAL offered more accurate and actionable information compared with noninvasive tests such as upper respiratory swabs or blood cultures, which often didn't align with the final diagnosis.
While BAL is sometimes delayed because of safety concerns or variable diagnostic yield, the study supported its early use in immunocompromised pediatric patiets presenting with respiratory symptoms.
The findings suggested that BAL may be both a safe and effective diagnostic tool that can help reduce unnecessary antimicrobial use and support more targeted care in this high-risk population.
Disclosures and funding details are available in the original study.
Source: Journal of the Pediatric Infectious Diseases Society