
Karius Study Demonstrates the Ability for NGS Technology to Better Detect/Treat Pneumonia Pathogens in Immunocompromised Patients
Pneumonia is a serious and often life-threatening condition, particularly for individuals with blood cancers, who are inherently immunocompromised due to their underlying medical conditions and treatments. Accurate and timely diagnosis of the specific pathogens causing pneumonia in these patients has posed significant challenges. A new multi-center study, the Pneumonia in the ImmunoCompromised – Use of Karius Test for the Detection of Undiagnosed Pathogens (PICKUP), has demonstrated the ability of the Karius Test®, a blood test based on metagenomics next-generation sequencing of microbial cell-free DNA, to improve the diagnosis of pneumonia in immunocompromised individuals.
The PICKUP Study was a significant collaborative effort among ten prominent medical institutions, including Duke University Health System, University of Pittsburgh Medical Center, Fred Hutchinson Cancer Research Center, MD Anderson Cancer Center, City of Hope, Tulane Medical Center, University of California, San Francisco Medical Center, University of Colorado Denver, Weill Cornell Medicine, and Memorial Sloan Kettering Cancer Center. The study aimed to investigate the potential of the Karius Test to enhance the identification of pathogens causing pneumonia in immunocompromised patients. The study evaluated patients undergoing hematopoietic cell transplantation and treatment for hematologic malignancies who often experience pneumonia complications. When these patients develop pneumonia symptoms, there is often a challenge in trying to identify the causative pathogen. Current diagnostic standards yield results for fewer than half of these patients undergoing bronchoscopy and extensive noninvasive testing. Clinicians must carefully assess the risks of invasive procedures in these medically fragile patients, often facing low diagnostic yields.
In the study, the Karius Test was combined with traditional diagnostic testing, leading to a significant 40% increase in the identification of causative pathogens, enhancing the accuracy of diagnoses. The key findings of the study include that the Karius Test identified the probable cause of pneumonia in 12% of patients when all usual care testing failed to do so. That antimicrobial therapy could have been optimized in 81% of patients in whom the Karius Test exclusively identified a probable cause of pneumonia. Additionally, the Karius Test successfully identified pathogens that are challenging to detect through conventional methods, such as Rhizomucor pusillus, Nocardia cyriacigeorgica, Legionella species, and Aspergillus fumigatus. Overall, the PICKUP Study demonstrates how noninvasive plasma microbial cell-free DNA (mcfDNA) sequencing can enhance the management of pneumonia which is critical for patients with hematologic malignancies and blood cancers where timely and accurate diagnosis can be the difference between life and death.