Tag Archive for: Iman Sami Zakhari

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Therapeutic antibiotics associated with reductions in microbial diversity in CF

person pouring pills from bottle to hand

Researchers found that both insufficient beta-lactam pharmacokinetics (PK) and broad-spectrum antibiotics were associated with a greater decrease in species richness at the end of antibiotic therapy compared to pulmonary exacerbations onset.

There are more than 70,000 children and adults living with cystic fibrosis (CF) worldwide. Those with this progressive disease frequently suffer from recurrent episodes of lung infection and inflammation called pulmonary exacerbations.

In a new observational study led by Andrea Hahn, M.D., infectious diseases specialist at Children’s National Hospital, researchers found that both insufficient beta-lactam pharmacokinetics (PK) and broad-spectrum antibiotics were associated with a greater decrease in species richness at the end of antibiotic therapy compared to pulmonary exacerbations onset.

In prior studies evaluating the association between beta-lactam PK, insufficient beta-lactam PK was associated with reduced short-term decreases in microbial diversity compared to sufficient beta-lactam dosing. In this study researchers found that insufficient beta-lactam PK was associated with a greater short-term decrease in microbial diversity.

Dr. Hahn’s team also found that an increased presence of beta-lactam antibiotic resistance genes was associated with lower microbial diversity and lower lung function.

These studies suggest that community-level antibiotic resistance, rather than the resistance patterns of the most prevalent bacteria identified in cultures, may serve as a useful predictor of lung function recovery in individuals with cystic fibrosis (CF). This finding may aid clinicians in selecting the most effective antibiotics to treat pulmonary exacerbations in CF patients, thus enhancing their clinical outcomes.

Read the full study in Nature’s Scientific Reports.

Authors on the study from Children’s National Hospital include Andrea Hahn, M.D., M.S., Aszia Burrell, Hollis Chaney, M.D.Iman Sami-Zakhari, M.D.Anastassios Koumbourlis, M.D., M.P.H., and Robert J. Freishtat, M.D., M.P.H.

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Effect of antibiotics on microorganisms and lung function in children with CF

girl looking at medicine bottle

The study suggests that the use of antibiotics to treat PEx in children with CF may not be as harmful to the airway microbiome as previously believed.

Cystic fibrosis (CF) is a disease that affects many people, especially children. Pulmonary exacerbations (PEx) are common in people with CF and can cause a decline in lung function. These PEx are often treated with antibiotics, but little is known about how antibiotics affect the airway microbiome (the collection of microorganisms in the lungs) of people with CF over time.

Experts from Children’s National Hospital took part in a recent study which looked at how the airway microbiome and lung function of children with CF changed over the course of a year following an initial PEx. The study found that the diversity of the airway microbiome increased over the year despite a decrease in lung function associated with repeated PEx events requiring antibiotic therapy. This suggests that repeated treatment with antibiotics may not have a negative impact on the overall diversity of microorganisms in the lungs.

It is important for pediatricians to understand how antibiotics affect the airway microbiome in children with CF because it can help them make more informed decisions about treatment options. The findings of this study suggest that the use of antibiotics to treat PEx in children with CF may not be as detrimental to the airway microbiome as previously thought. This information can help pediatricians provide better care for children with CF and ultimately improve their overall health outcomes.

You can read the full study, Impact of Antibiotics on the Lung Microbiome and Lung Function in Children With Cystic Fibrosis 1 Year After Hospitalization for an Initial Pulmonary Exacerbation, in Open Forum Infectious Diseases.

Authors on the study from Children’s National Hospital include Zaina Inam, M.D., Aszia Burrell, Hollis Chaney, M.D., Iman Sami-Zakhari, M.D., Anastassios Koumbourlis, M.D., M.P.H., Robert J. Freishtat, M.D., M.P.H., and Andrea Hahn, M.D., M.S.

pill bottles and pills

Impact of anaerobic antibacterial spectrum on cystic fibrosis

Researchers from Children’s National Hospital found that broad spectrum antianaerobic therapy had greater and longer lasting effects on the lung microbiome of persons with cystic fibrosis.

Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the chloride ion channel encoding CF transmembrane conductance regulator gene, leading to multiple morbidities and early mortality. In a new clinical study, researchers from Children’s National Hospital found that broad spectrum antianaerobic therapy had greater and longer lasting effects on the lung microbiome of persons with CF.

They found this difference when comparing the microbiology and clinical outcomes in children with CF who were treated with “broad” or “narrow” antianaerobic antibiotics for exacerbations of their disease. While there are many factors that determine whether “narrow” or “broad” spectrum antibiotics are used, the data showed that the recovery of pulmonary function was similar between those groups.

“The findings prove that most providers are following best practices when treating patients with cystic fibrosis using the narrowest spectrum of antibiotics possible, and reserving broad spectrum agents for more advanced disease when culture data shows more resistant bacteria,” says  Michael Bozzella, the study’s lead author.

The study, published in the Pediatric Infectious Disease Journal, analyzed how the spectrum of antibiotics prescribed to patients with cystic fibrosis impacts the population of bacteria in their lungs how it ties back to lung function.

“Research like this improves antibiotic and antimicrobial stewardship,” said Bozzella. “When speaking with families and patients with cystic fibrosis, providers can be more aware of the relationship between lung microbiome, disease state, and antibiotics and create more holistic treatment plans.”

Dr. Bozzella did this research as a fellow at Children’s National and he’s now an Infectious Disease Attending Physician at Children’s Hospital Colorado. Additional authors from Children’s National include: Andrea Hahn, M.D., M.S., Hollis Chaney, M.D.Iman Sami Zakhari, M.D.Anastassios Koumbourlis, M.D., M.P.H. and Robert Freishtat, M.D., M.P.H.

mother helping child with inhaler

Beta-lactam and microbial diversity in cystic fibrosis

mother helping child with inhaler

The study, published in the Journal of Investigative Medicine, examined the hypotheses that beta-lactam antibiotic PK and PD is associated with changes in richness and alpha diversity following treatment of a pulmonary exacerbations and determined associations between antibiotic PK, PD, antibiotic resistance and lung function.

Cystic fibrosis (CF) is a chronic lung disease that affects more than 30,000 people in the United States and 70,000 people worldwide. While this chronic disease is characterized by acute pulmonary exacerbations that are frequently treated with antibiotics, the impact of antibiotics on airway microbial diversity remains a critical knowledge gap.

A new study led by researchers at Children’s National Hospital found that beta-lactam antibiotic pharmacokinetic (PK) and pharmacodynamic (PD) target attainment during treatment is associated with suppressed recovery of microbial diversity, following a pulmonary exacerbation in children and adolescents with CF.

“By laying the groundwork for understanding how antibiotic PK may influence microbial diversity following pulmonary exacerbation, we hope to identify improved ways to guide antibiotic therapy in persons with CF,” says Andrea Hahn, M.D., M.S., an infectious diseases specialist at Children’s National and lead author of the study.

The study, published in the Journal of Investigative Medicine, examined the hypotheses that beta-lactam antibiotic PK and PD is associated with changes in richness and alpha diversity following treatment of a pulmonary exacerbations and determined associations between antibiotic PK, PD, antibiotic resistance and lung function.

“Beta-lactam antibiotics are frequently used to treat pulmonary exacerbations in persons with CF, yet are not routinely optimized,” says Dr. Hahn. “This study demonstrates the importance of beta-lactam PK’s on changes within the airway microbiome and provides context for care providers regarding the potential long-term impacts of antibiotic use in persons with CF, to ensure that we are optimizing therapy with each pulmonary exacerbation.”

Additional authors from Children’s National include: Aszia Burrell, Hollis Chaney, M.D.Iman Sami Zakhari, M.D.Anastassios Koumbourlis, M.D., M.P.H. and Robert Freishtat, M.D., M.P.H.

girl with cystic fibrosis getting breathing treatment

The role of long-chain fatty acids in cystic fibrosis inflammation

girl with cystic fibrosis getting breathing treatment

A recent study sheds light on the microbiologic triggers for lung inflammation and pulmonary exacerbations in cystic fibrosis.

Cystic fibrosis is an autosomal recessive disease that affects more than 70,000 people worldwide and results in a progressive decline of lung function. Patients with cystic fibrosis experience intermittent episodes of acute worsening of symptoms, commonly referred to as pulmonary exacerbations. While Staphylococcus aureus and Pseudomonas aeruginosa are thought to contribute to both lung inflammation and pulmonary exacerbations, the microbiologic trigger for these events remains unknown. Andrea Hahn, M.D., M.S., and her colleagues at Children’s National Hospital recently shed light on this matter by studying the changes in bacterial metabolic pathways associated with clinical status and intravenous (IV) antibiotic exposure in cystic fibrosis patients.

The researchers found increased levels of long-chain fatty acids (LCFAs) after IV antibiotic treatment in patients with cystic fibrosis. LCFAs have previously been associated with increased lung inflammation in asthma, but this is the first report of LCFAs in the airway of people with cystic fibrosis. This research indicates that bacterial production of LCFAs may be a contributor to inflammation in people with cystic fibrosis and suggests that future studies should evaluate LCFAs as predictors of pulmonary exacerbations.

Additional authors from Children’s National include: Hollis Chaney, M.D., Iman Sami Zakhari, M.D., Anastassios Koumbourlis, M.D., M.P.H. and Robert Freishtat, M.D., M.P.H.

Read the full study in Pediatric Research.