Among patients who undergo endobronchial ultrasound-guided transbronchial biopsy using a guide sheath (EBUS-GS-TBB) for diagnosing lung cancer, cavitation and low-density areas inside the target lesion on CT and stenosis of the responsible bronchus are risk factors for infection after the procedure, according to a study published in CHEST.
“Infectious complications after [transbronchial biopsy] constitute a serious clinical problem because they might delay the start of treatment or cause the intended treatment to be modified to a milder one,” said Tomohide Souma, MD, of the department of respiratory medicine at Fujita Health University in Toyoake, Japan, and colleagues. “The precise mechanism of such complications is still unclear, and effective prophylaxis procedures have not been established. ... Thus, it is very important to identify the risk factors for infectious complications after TBB if and when these complications are to be avoided.”
To evaluate potential risk factors for infectious complications after EBUS-GS-TBB in a large sample of patients, Dr. Souma and colleagues retrospectively studied the medical records of 1,045 consecutive patients (median age, 72; 68% male) who underwent EBUS-GS-TBB between January 2013 and December 2017 at Fujita Health University Hospital.
In all, 47 patients developed infections, a cumulative incidence of about 4.5%. Infections included pneumonia (51.1%), intratumoral infection (29.8%), and three cases each of lung abscess, pleurisy, and empyema. Three patients, two with empyema and one with lung abscess, died within 1 month before administration of anticancer treatment. “In total, more than 40% of patients with post–EBUS-GS-TBB infection were unable to receive preplanned anticancer treatment,” the researchers said.
On multivariate analysis, cavitation in the lesion (odds ratio, 3.63), low-density areas in the lesion (OR, 13.26), and bronchoscopic findings of responsible bronchus stenosis (OR, 7.82) were significantly associated with development of infections post biopsy.
An analysis that matched 89 patients who received prophylactic antibiotics with controls who did not receive prophylactic antibiotics did not find that prophylactic antibiotics significantly reduced the likelihood of post–EBUS-GS-TBB infection.
“Notably, three risk factors found in our study indicate that the inflammation-prone status of lesions may be the most important factor for developing post–EBUS-TBB infection,” Dr. Souma and colleagues said. “Although our study does not rebuff the role of antibiotics in postbronchoscopy infection therapy, clinicians should notify patients that post-TBB infection may occur despite the use of prophylactic antibiotics. We recommend that careful and frequent follow-up be applied to patients undergoing diagnostic EBUS-GS-TBB with reference to the risk factors identified in our study.”
A. Christine Argento, MD, FCCP, assistant professor of medicine and thoracic surgery and director of the interventional pulmonary fellowship program at Northwestern University, Chicago, noted that this is an important study on a topic that has not been well described in the past.
“This paper ... identifies three factors that were associated with infectious complications – namely, cavitation, low density areas, and a visibly stenosed bronchus leading to the lesion,” she said. “When planning bronchoscopy to sample lesions that fit one of these three criteria, I will likely be more cautious in the future meaning that in these cases, I would limit biopsies to 6-8 pieces which is typically sufficient and I would minimize any trauma to the bronchus leading to the lesion, as if the bronchus is already stenosed on bronchoscopic inspection it is likely inflamed and will only be exacerbated by repeated manipulation and insertions with the bronchoscope and guide sheath leading to a postobstructive phenomenon that was observed in this cohort.
“As far as pleurisy and empyema, it is not described if [the investigators] used fluoroscopy, but this would be an important aspect,” she added. “Ideally, one would not cause disruption of the pleural surface as contamination from the lung to the pleural space can have serious and prolonged infectious consequences as was reported in this study. Fluoroscopy would help the operator to avoid taking samples that would be too close to the pleural surface and could potentially decrease this complication.
“In the United States, it is not always standard practice to see patients 5-7 days following bronchoscopy to assess for complications. Although some of these patients would have presented for evaluation with symptoms, presumably several of these patients would not have. Also pre- and postbronchoscopy labs are not commonly drawn in the United States and so a rise in white blood cells or C-reactive protein would not be known.
“Finally, [the investigators] point out that prophylactic antibiotics do not seem to be effective, and I would agree based on their results. I would only consider using antibiotics as a directed measure if the patient develops infectious complications and the antibiotic choice and duration of therapy would be tailored to the specific complication encountered,” she said.
The researchers had no disclosures.
SOURCE: Souma T et al. CHEST. 2020 Mar 4. doi: 10.1016/j.chest.2020.02.025.