Test Id : KBAL
Karius Focus, Bronchoalveolar Lavage
Useful For
Suggests clinical disorders or settings where the test may be helpful
Detection of microbial cell-free DNA from over 500 bacteria, fungi, parasites, and DNA viruses known to cause lung infections in bronchoalveolar lavage fluid
Highlights
The Karius Focus: BAL test employs pathogen-agnostic metagenomic microbial cell-free DNA (mcfDNA) sequencing of bronchoalveolar lavage fluid for the unbiased detection, identification and classification of over 500 human pathogens that cause lung infections.
This test is designed to quickly identify the etiology of lung infections and improve diagnostic yield over standard of care testing.
For more information see Karius Focus: BAL A new diagnostic tool for patients with suspected lung infection.
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For information regarding when to order the Karius Spectrum test or diagnostic algorithms, see Considerations for the Implementation of the Karius Spectrum and Karius Focus BAL Tests.
Method Name
A short description of the method used to perform the test
Metagenomic Sequencing
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
Karius
Karius Focus
Bronchoalveolar Lavage
BAL mcfDNA
BAL microbial cell free DNA
BAL next generation sequencing
BAL mNGS
BAL metagenomics
BAL metagenomic sequencing
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For information regarding when to order the Karius Spectrum test or diagnostic algorithms, see Considerations for the Implementation of the Karius Spectrum and Karius Focus BAL Tests.
Specimen Type
Describes the specimen type validated for testing
Bronchoalveolar Lavage
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Container/Tube: Sterile, leak-proof freezable container
Specimen Volume: 1.5 mL
Collection Instructions:
1. Collect bronchoalveolar lavage fluid (BALF) specimen according to your institutional guidelines.
2. Within 12 hours of specimen collection, transfer at least 1.5 mL of BALF specimen to a sterile container and freeze.
3. See Karius Focus: BAL Specimen Collection and Preparation Process for complete instructions.
Additional Information:
2. Specimen trap collection containers (with suction catheters attached) will be rejected due to the high risk of leakage and contamination upon opening. Avoid use of these for BALF specimens.
3. If specimen transfer into an acceptable sterile container is necessary, perform specimen transfer in a biosafety cabinet. Place the container in a separate sealed plastic bag.
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
See Specimen Required
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Bronchoalveolar Lavage | Frozen | 180 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Detection of microbial cell-free DNA from over 500 bacteria, fungi, parasites, and DNA viruses known to cause lung infections in bronchoalveolar lavage fluid
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For information regarding when to order the Karius Spectrum test or diagnostic algorithms, see Considerations for the Implementation of the Karius Spectrum and Karius Focus BAL Tests.
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
The Karius Focus BAL test is a bronchoalveolar lavage fluid-based microbial cell-free DNA (mcfDNA) metagenomic sequencing diagnostic test for agnostic detection, identification, and quantification of mcfDNA from human lung pathogens, including bacteria, fungi, parasites, and DNA viruses. Patients who may be appropriate for testing include individuals with suspected pneumonia or other pulmonary infections who are undergoing bronchoscopy to identify an infectious cause as well as those with imaging concerning opportunistic, atypical, or fungal pneumonia or not responding to empiric therapy and in need of rapid diagnostic testing.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
An interpretive report will be provided.
Interpretation
Provides information to assist in interpretation of the test results
A positive result indicates that microbial cell-free DNA (mcfDNA) of one or more potentially pathogenic microorganisms was detected.
A negative result indicates absence of detectable mcfDNA from potentially pathogenic bacteria, fungi, parasites, or DNA viruses. A negative result does not rule out the presence of a pathogen due to lack of a reference sequence in the database used or the presence of mcfDNA in quantities lower than the assay's limit of detection. Results should be interpreted in the clinical context of the patient.
For more information see Understanding the Karius Focus: BAL Test Report.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
The Karis Focus Test does not detect RNA viruses. The test has been validated only for bronchoalveolar lavage fluid specimens.
Supportive Data
A robust analytical validation strategy characterized Karius Focus: BAL test performance in light of metagenomic-specific challenges using 11 diverse pathogens that span the extremes of over 500 pathogens characteristics. Clinical performance of microbial cell-free DNA (mcfDNA) sequencing of bronchoalveolar lavage fluid (BALF) was compared to standard of care (SOC) testing results in a prospective observational study conducted at 10 tertiary care centers, including 118 patients with a hematologic malignancy undergoing bronchoscopy for suspected pneumonia.(1) mcfDNA sequencing was performed using the Karius Focus BAL test to detect and quantify mcfDNA from over 500 organisms in BALF. Results of mcfDNA sequencing and all BALF-based SOC testing were adjudicated by a panel of experts for identification of probable causes of pneumonia.
Microbial cell-free DNA sequencing of BAL identified an adjudicated probable cause of pneumonia in 40/118 participants (33.9%, 95% CI 25.1-42.7), compared to SOC which identified an adjudicated probable cause of pneumonia in 29/118 (24.6%, 95% CI 16.5-32.6). mcfDNA sequencing of BALF exclusively identified a probable cause of pneumonia in 15/118 participants (12.7%, 95% CI 6.4-19.1), resulting in a relative diagnostic yield increase of 15/29 (51.7%, 95%CI 33.0-70.4). In addition, mcfDNA sequencing of BALF identified additional or alternative adjudicated causes of pneumonia in 7/29 (24.1%, 95% CI 7.9-40.4) specimens with a SOC-adjudicated cause of pneumonia and provided speciation for genus-level SOC causes of pneumonia in all 5 cases where SOC identified the cause at the genus level. Based on the composite results of all diagnostics tests, mcfDNA sequencing of BAL demonstrated 90.9% +/-9.1% positive percent agreement (PPA), compared to PPA of 65.9% +/-14.5% for all SOC-BAL testing combined.
For more information see Analytical and Clinical Validation of Microbial Cell-free DNA Sequencing of Bronchoalveolar Lavage Fluid.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Bergin SP, Chemaly RF, Dadwal SS, Hill JA, Lee YJ, Haidar G, et al. Plasma microbial cell-free DNA sequencing in immunocompromised patients with pneumonia: A prospective observational study. Clin Infect Dis. 2024;78(3):775-784
2. Blauwkamp TA, Brick K, Jarman K, Zielinska A, et al. Analytical and Clinical Validation of Microbial Cell-free DNA Sequencing of Bronchoalveolar Lavage Fluid Test. ASM Microbe 2025 Poster CIV-P-403
3. Cheng GS, Crothers K, Aliberti S, et al. Immunocompromised host pneumonia: Definitions and diagnostic criteria: An official American Thoracic Society Workshop report. Ann Am Thorac Soc. 2023;20(3):341-353. doi:10.1513/AnnalsATS.202212-1019ST
Method Description
Describes how the test is performed and provides a method-specific reference
One mL of bronchoalveolar lavage fluid (BALF) is treated with proteinase K to break down proteins, spiked with internal controls, and prepared for sequencing with an in-matrix library preparation method. Pooled libraries were sequenced on Illumina NextSeq500/550 or NovaSeq6000 platforms, yielding approximately 24M reads per sample. The test employs multiple quality control strategies designed to control common sources of error in metagenomic tests including contamination, carry-over cross contamination, pathogen cross reactivity, and impaired limits of detection. The target agnostic chemistry process generates a data file containing all detected sequencing reads. The sequencing reads from each sample are aligned against a highly curated reference genome database containing thousands of microbial species and a high-quality human reference. Potentially pathogenic species with statistically significant numbers of aligned reads that also pass our analytical and clinical thresholds are reported. The list of reportable pathogens includes over 500 bacteria, DNA viruses, fungi, and parasites known to cause lung infections.
For reporting purposes, microbes are functionally categorized as:
1. Obligate pathogen, likely to cause lung infection at any concentration
2. Opportunistic pathogens, may cause disease, especially in immunocompromised hosts
3. Microbes with pathogenic potential and DNA viruses, which may either cause lung infection or represent commensal organisms
4. Upper respiratory tract flora, which are more commonly commensal organisms than the cause of lung infections
For a listing of pathogens, see https://kariusdx.com/our-solution/pathogens?product=bal
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Monday through Saturday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
The Karius Focus: BAL test was developed and its performance characteristics determined by Karius. The Karius laboratory is certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA '88) and is accredited by the College of American Pathologists (CAP) to perform high-complexity laboratory testing. This test has not been reviewed or cleared by the US Food and Drug Administration.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
81479
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| Test Id | Test Order Name | Order LOINC Value |
|---|---|---|
| KBAL | Karius Focus, BAL | Not Provided |
| Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
|---|---|---|
| KBAL | Karius Focus, BAL | Not Provided |