An updated clinical guideline on pneumonia emphasizes antimicrobial stewardship with recommendations for increased microscopic studies of respiratory tract specimens in certain patients and revised recommendations for empiric treatment strategies. The American Thoracic Society (ATS)/Infectious Diseases Society of America (IDSA) ad hoc committee on community-acquired pneumonia (CAP) in adults published the guideline online October 1 in the American Journal of Respiratory and Critical Care Medicine. The recommendations update 2007 guidance and are primarily focused on adults who are not immunocompromised. "CAP remains one of the leading causes of deaths in the world," Grant Waterer, MBBS, PhD, co-chair of the guideline committee and a professor of medicine at the University of Western Australia in Perth, said in a news release. "Not only has there been new data in the past decade, but there is now a strong national and international focus on antibiotic stewardship. It was time to update the guideline so that clinicians could be certain they were still practicing evidence-based care." "[T]he resistance patterns have changed some of our recommendations, but the first-line agents are fairly similar as the last time around," co-committee chair Joshua P. Metlay, MD, PhD, from Massachusetts General Hospital and Harvard Medical School in Boston, told Medscape Medical News. "We are suggesting that physicians and health centers continue to do diagnostic tests so we can learn more about the epidemiology of what's going on here in the hope that we'll have better-targeted therapy," Metlay said. The authors identified a list of 16 core clinical questions identified by the committee as high priority and made recommendations in response to those questions. No Hospital- vs Community-Acquired Distinction In the updated guideline, the authors recommend sputum and blood culture for severely ill patients and for all inpatients who have received empiric treatment for Methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa. (The 2007 guideline recommended sputum and blood culture for severely ill patients.) Macrolide monotherapy is now conditionally recommended for outpatients on the basis of resistance levels; in the 2007 guideline, macrolide monotherapy was strongly recommended for outpatients. The authors recommend against the use of serum procalcitonin for distinguishing between bacterial and viral infection and whether or not a patient requires antibacterial therapy. "Although low levels of biomarkers such as procalcitonin decrease the likelihood that patients have bacterial infections, these biomarkers do not completely rule out bacterial pneumonia in an individual patient with sufficient accuracy to justify initially withholding antibiotic therapy, especially among patients with severe CAP," the authors write. The committee also recommends against the use of corticosteroids in patients with community-acquired pneumonia, but say clinicians may consider using them for patients with refractory septic shock. Although the previous guidelines did not address corticosteroids, there has been a great deal of literature on the use of corticosteroids in patients with pneumonia, Metlay said. "On the final analysis, it's probably not a preferred therapy for most patients with pneumonia as an adjunct therapy," he added. Notably, the updated guideline recommends abandoning the use of the healthcare-associated pneumonia category. Rather, the focus is on using local epidemiology data and validated risk factors to determine whether the patient needs coverage for MRSA or P aeruginosa and an increased emphasis on deescalating treatment if culture results are negative. "The category itself poorly predicts situations where patients have drug-resistant pathogens, and it has also been overused as a category such that there's a lot of empiric therapy of patients with pneumonia with very broad-spectrum antibiotics that are probably causing more harm than good," Metlay explained. "There's really growing evidence that the implementation of that category has led to excess overuse of broad-spectrum antibiotics and not improved outcomes — and actually may have worsened outcomes. So it was time to come up with a better strategy to deal with the small but real risk that, in some patients, there are causative agents that are not covered by the usual antibiotics that we prescribe," he added. The updated clinical guideline recommends both β-Lactam/macrolide and β-lactam/fluoroquinolone combinations for treatment but says there is stronger evidence favoring a β-lactam/macrolide combination. In addition, the routine use of follow-up chest imaging is not recommended, but the committee notes that patients who are eligible for lung cancer screening should undergo chest imaging as clinically indicated. Metlay said that given how common and lethal pneumonia is, it is unfortunate that there is not more quality research on diagnostics and therapeutics for pneumonia. "There is a bit of a disconnect with the prevalence of the problem and the amount of research that's going on," he explained. Am J Respir Crit Care Med. Published online October 1, 2019. Full text Source