Test Catalog

Test Id : BRCMG

Brucella Antibody Screen, IgM and IgG, ELISA, Serum

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with suspected brucellosis

Profile Information
A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.

Test Id Reporting Name Available Separately Always Performed
BRCM Brucella Ab Screen, IgM ELISA, S No Yes
BRCG Brucella Ab Screen, IgG ELISA, S No Yes
BRCI Brucella Ab Screen Interpretation No Yes

Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.

Test Id Reporting Name Available Separately Always Performed
BRUTA Brucella Ab, Agglutination, S Yes No

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If Brucella antibody screen, IgM or IgG is either positive or equivocal, then confirmation by Brucella total antibody agglutination testing will be performed at an additional charge.

Method Name
A short description of the method used to perform the test

Enzyme-Linked Immunosorbent Assay (ELISA)

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

Brucella Ab Screen, IgM/IgG ELISA, S

Lists additional common names for a test, as an aid in searching

Brucella abortus

Brucella Serology

Febrile Agglutinins (? FOR SPECIFIC TEST)

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If Brucella antibody screen, IgM or IgG is either positive or equivocal, then confirmation by Brucella total antibody agglutination testing will be performed at an additional charge.

Specimen Type
Describes the specimen type validated for testing


Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL


If not ordering electronically, complete, print, and send Infectious Disease Serology Test Request (T916) with the specimen.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.4 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Gross lipemia Reject
Other Heat inactivated

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
Serum Refrigerated (preferred) 14 days
Frozen 14 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating patients with suspected brucellosis

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

If Brucella antibody screen, IgM or IgG is either positive or equivocal, then confirmation by Brucella total antibody agglutination testing will be performed at an additional charge.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Brucellosis, major disease in humans and domesticated animals, is a systemic bacterial infection caused by Gram negative coccobacilli of the genus Brucella. Brucellosis is a zoonotic disease and a variety of domestic animals serve as reservoir species: Brucella infects goats (Brucella melitensis), cattle (Brucella abortus), swine (Brucella suis), and dogs (Brucella canis). Transmission to humans results from direct contact with infected animals, exposure to infectious aerosols, or ingestion of unpasteurized dairy products; human-to-human transmission does not occur. While few cases are reported in the US, the majority of cases occur in the Mediterranean region, Western Asia, and parts of Latin America and Africa. Three species of Brucella commonly cause disease in humans: B melitensis, B suis, and B abortus. Clinical manifestations of brucellosis consist of fever, sweats, malaise, weight loss, headache, and weakness. The onset may be insidious or acute, generally beginning within 2 to 4 weeks after exposure. Any organ or system of the body may be involved, although death is uncommon. Presumptive diagnosis of brucellosis can be made by detection of high or rising titers of specific antibodies, typically to smooth lipopolysaccharide (S-LPS), a major antigenic virulence determinant. Serologic tests using S-LPS can detect antibody to the three major Brucella species due to this shared epitope. IgM antibodies appear during the first week of infection followed by a switch to IgG synthesis during the second week. A variety of serologic tests have been used for diagnosis of Brucella infection. Detection of anti-Brucella antibodies using ELISA has been demonstrated to be a sensitive diagnostic approach. However, all specimens testing positive by an ELISA should be confirmed by an agglutination method as a means to increase assay specificity.

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.






Reference values apply to all ages.

Provides information to assist in interpretation of the test results

In the acute stage of the disease, there is an initial production of IgM antibodies followed closely by production of IgG antibodies. IgG-class antibodies may decline after treatment; however, high levels of circulating IgG-class antibodies may be found without any active disease.


Rising levels of specific antibody in paired sera can be regarded as serological evidence of recent infection. The presence of specific IgM in a single specimen may also indicate a recent infection, although IgM-class antibodies may persist for months following acute disease.


The CDC recommends that specimens testing positive for IgG or IgM by ELISA be confirmed by a Brucella-specific agglutination method.(1)


The CDC/Council of State and Territorial Epidemiologists case definition for human brucellosis states that the laboratory criteria for diagnosis includes 1) isolation of Brucella species from a clinical specimen, 2) four-fold or greater rise in Brucella agglutination titer between acute- and convalescent-phase serum specimens obtained more than 2 weeks apart and studied at the same laboratory, and/or 3) demonstration by immunofluorescence of Brucella species in a clinical specimen.


Positive results by ELISA that are not confirmed by Brucella-specific agglutination may represent false-positive screening results. If clinically indicated, a new specimen should be tested after 14 to 21 days.


If results of ELISA are negative and a recent infection is suspected, a new specimen should be tested after 14 to 21 days.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

This test utilizes antigen derived from Brucella abortus strain W99. However, significant cross-reactivity exists for other Brucella species (except B canis) and, therefore, the assays should not be used to differentiate infection at the species level.


B canis, a rare cause of brucellosis, may not be detected by this method.


Detection of specific IgM or IgG-class antibody to B melitensis and B suis by this method has not been determined.


ELISA tests are intended to be used as a screen only. Positive results should be followed up using an agglutination assay for confirmation. Results must be used in conjunction with symptoms, patient history, and other clinical findings.


B abortus strain RB51 is used for vaccination of animals in the US. There are currently no serologic tests to detect an antibody response to strain RB51 in humans. Per CDC guidelines, routine clinical serology tests for Brucella do not detect an antibody response to strain RB51. Note that other strains besides RB51 may be used for vaccinating animals outside of the US.(2)

Supportive Data

According the manufacturer's package insert, 127 patient samples testing positive with the Rose-Bengal test were also examined with the Eurroimmun anti-Brucella abortus ELISA, and 160 blood donors were tested. Data from these studies were as follows for anti-B abortus:

-IgG: sensitivity, 78.0%; specificity, 98.0%

-IgM: sensitivity, 56.0%; specificity, 98.0%

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Public health consequences of a false-positive laboratory test result for Brucella-Florida, Georgia, and Michigan, 2005, MMWR Morb Mortal Wkly Rep 2008 Jun 6;57(22);603-605

2. Gunes H, Dogan M: False-positivity in diagnosis of brucellosis associated with Rev-1 vaccine. Libyan J Med 2013;8:20417

3. Corbel MJ: Brucellosis: an overview. Emerg Infect Dis 1997;3:213-221

4. Araj GF, Lulu AR, Saadah MA, et al: Rapid diagnosis of central nervous system brucellosis by ELISA. J Neuroimmunol 1986;12:173-182

Method Description
Describes how the test is performed and provides a method-specific reference

Serum is tested using an ELISA Test Kit containing microtiter strips with wells coated with Brucella abortus antigens (strain W99). In the first reaction step, diluted patient samples are incubated in the wells. Specific IgG or IgM antibodies, if present in the serum, will bind to the antigens. To detect the bound antibodies, a second incubation is carried out using an enzyme-labeled antihuman IgG or antihuman IgM (enzyme conjugate). After addition of the substrate, tetramethylbenzidine (TMB)/hydrogen peroxide and a sulphuric acid stop solution, the resulting color reaction is measured photometrically at a wavelength of 450nm.(Package insert: Anti-Brucella abortus ELISA Test Instruction, Euroimmun Medizinische Labordiagnostika, Lubeck, Germany 02/2018)

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.

Tuesday, Thursday

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.

Same day/1 to 3 days - If reflex testing is required, additional days are needed to perform agglutination testing.

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


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 Regional Manager. 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.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved 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.

86622 x 2-Brucella antibody, IgG and IgM

86622-Brucella total antibody, agglutination (if appropriate)

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
BRCMG Brucella Ab Screen, IgM/IgG ELISA, S 91140-4
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.
BRCM Brucella Ab Screen, IgM ELISA, S 24388-1
BRCG Brucella Ab Screen, IgG ELISA, S 24387-3
BRCI Brucella Ab Screen Interpretation 66485-4

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports