Antibiotic Exposure Following HCT Increases Risk for Respiratory Viral Disease Progression

For patients who have undergone allogenic hematopoietic cell transplantation (HCT), exposure to antibiotics prior to respiratory viral infection can increase the risk of disease progression.

This new finding was announced by a team of investigators from the University of Washington, Fred Hutch, and Seattle Children’s Hospital in a poster presentation session at the 2020 Transplantation and Cellular Therapy (TCT) Meetings of ASBMT and CIBMTR.

It was previously identified through animal model research that immunomodulate effects of changes in the microbiota were likely linked to the increased risk of disease progression following antibiotic exposure.

In order to address gaps in the knowledge, a team of investigators set out to identify specific antibiotics that may be associated with progression of select respiratory viral diseases.

The investigators analyzed data from 469 individuals who underwent allogenic HCT and had a subsequent respiratory viral infection within the first 100 days following the transplant between April 2008 and September 2018. Specifically, the investigators looked at individuals who had parainfluenza (93), respiratory syncytial virus (54), human metapneumovirus (27), or human rhinovirus (295). Of these individuals, 124 experienced progression to lower respiratory tract disease.

The study team assessed antibiotic exposure in the 21 days prior to onset of respiratory viral infection onset. The investigators looked at any versus no use of specific antibiotics and the total number of antibiotic days.

Using cumulative incidence curves, the team estimated the probability of disease progression, with death classified as a competing risk. The investigators also used Cox proportional hazard models to examine associations between antibiotic exposure and disease progression risks, with adjustments for type of respiratory infection, age, steroid use, lymphopenia, and neutropenia before infection onset. The data were censored at point of death, discharge, or 30 days post-infection onset.

According to the results, the cumulative incidence or disease progression during the 21 days prior to onset of illness was a median of 11 (range 0-56).

The investigators also report that progression to lower respiratory tract disease was associated with higher total antibiotic-days, use of antibiotics with broad anaerobic activity, and use of cephalosporins with limited anaerobic activity.

“This study suggests that cumulative exposure to antibiotics prior to [respiratory viral infection] is a risk factor for respiratory viral disease progression,” the investigators wrote in their abstract. “Despite complex antibiotic use patterns in HCT recipients, our findings also suggest antibiotics of varying spectra may be associated with respiratory viral disease progression.”

The abstract, What Types of Antibiotic Exposure Associated with Increased Risk of Respiratory Viral Disease Progression in Allogenic Hematopoietic Cell Transplant Recipients, was presented in a poster session on Saturday, February 22, 2020, at the 2020 Transplantation and Cellular Therapy (TCT) Meetings of ASBMT and CIBMTR in Orlando, Florida.