Diagnostic Application: Pneumonia
Study Site: OSF Saint Francis Medical Center5
39 years old with untreated HIV infection and respiratory failure requiring mechanical ventilation with an unclear etiology.
Tests Performed: Diagnostic tests performed for evaluation of pneumonia and other etiologies included absolute CD4 count of 6, HIV viral load of 332,909 copies/ml, CMV IgG positive; CXR with bilateral multinodular changes, chest CT with miliary lesions, brain MRI with multiple ring enhancing lesions; negative testing included: blood and BAL cultures; VZV, syphilis, and tuberculosis studies; Histoplasma/ Aspergillus/ Legionella/ Cryptococcus/ Influenza antigens.
(A) CT chest axial lung window showing miliary changes in both lungs; (B) CT chest axial lung window showing several nodules with developing central cavitation and bilateral consolidation; (C) coronal window showing bibasilar airspace disease with confluent consolidation throughout the lung bases5
Karius Test Result: Toxoplasma gondii
Outcome: Started 6-week course of pyrimethamine/sulfadiazine, discontinued piperacillin/tazobactam; resulting in significant clinical improvement allowing the patient to be started on antiretroviral therapy.
Study Site: 10 Medical Centers*
In a prospective, multi-center study enrolling adult patients with hematological malignancies or hematopoietic cell transplantation with suspected pneumonia, results from 160 patients meeting the pre-specified per-protocol population criteria, the Karius Test (KT) provided a 38.3% (18/47) relative increase of the total diagnostic yield in conjunction with standard of care (SOC) testing & additive diagnostic value (ADV) of 15.9% (18/113) via adjudication where SOC failed.**,6
*Please see PICKUP Study Summary for full list of enrolling centers
**Please see study for comparable tests
Study Site: Rady Children’s Hospital
In a retrospective study in 46 immunocompetent pediatric patients with complicated community acquired pneumonia, the Karius Test led to a change in antimicrobial management in 78% (35/46).7
Considerations for Use
*KT is an LDT. Clinicians should independently evaluate its use and interpret test results. This content is provided for informational purposes only and is not intended or implied to be an exhaustive list of consideration or substitute for existing medical expertise or guideline recommendations.
Presented at IDWeekTM 2022
A preview of early results on the additive diagnostic value of the Karius Test when used in conjunction with SOC for the diagnosis of suspected pneumonia.
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