Chlamydia Serology, IgM & IgG (Sendout)

Interpretation

Guidelines

• Washington DOH Notifiable Conditions

Method

Micro-Immunofluorescent Antibody (MIF)

Reference Range

See individual components

Ref. Range Notes

Interpretation:

Chlamydia pneumoniae IgM:

<1:10	IgM endpoint titers below 1:10 suggest that the patient does not have a current infection. These antibody levels may be found in patients with either no history of chlamydial infection or those with past infection whose antibody levels have dropped below detectable levels.
≥1:10	IgM endpoint titers of 1:10 or more are considered presumptive evidence of infection.

Chlamydia pneumoniae IgG:

<1:64	IgG endpoint titers below 1:64 suggest that the patient does not have a current infection. These antibody levels may be found in patients with either no history of chlamydial infection or those with past infection whose antibody levels have dropped below detectable levels.
≥1:64 and <1:512	A single specimen endpoint titer of 1:64 to 1:512 should be considered evidence of infection at an undetermined time. A second specimen collected 10 to 21 days after the original collection should be tested in parallel with the first. If the second specimen exhibits a titer 1:512 or more or a 4-fold increase over that of the initial specimen, current (acute) infection is indicated. Unchanging titers from 1:64 to 1:512 suggest past infection.
≥1:512	IgG endpoint titers of 1:512 or more are considered presumptive evidence of current infection.

C pneumoniae antibody is detectable in 25% to 45% of adults tested.

Chlamydia psittaci IgM:

<1:10	IgM endpoint titers below 1:10 suggest that the patient does not have a current infection. These antibody levels may be found in patients with either no history of chlamydial infection or those with past infection whose antibody levels have dropped below detectable levels.
≥1:10	IgM endpoint titers of 1:10 or more are considered presumptive evidence of infection.

Chlamydia psittaci IgG:

<1:64	IgG endpoint titers below 1:64 suggest that the patient does not have a current infection. These antibody levels may be found in patients with either no history of chlamydial infection or those with past infection whose antibody levels have dropped below detectable levels.
≥1:64	IgG endpoint titers of 1:64 or more are considered presumptive evidence of current infection.

Interferences and Limitations

Cautions:

Antichlamydial IgG can persist for years. All results from chlamydial serologies must correlate with clinical history and other data available to the physician.

Specimens collected too early during primary infection may not contain detectable antibodies. If chlamydial infection is suspected, a second specimen should be collected 10 to 21 days later and tested in parallel with the original specimen.

During a primary Chlamydia infection, the early antibody response may be cross-reactive with multiple Chlamydia species.

This assay does not report antibodies detected against Chlamydia trachomatis. Sera from suspected cases of lymphogranuloma venereum (LGV) should be tested by a Lymphogranuloma Venereum Differentiation Antibody Panel. LGV testing is not performed by Mayo Clinic Laboratories. Due to the limited sensitivity and specificity of Chlamydia serologic tests, patients with suspected C trachomatis infection should be tested by a molecular method when clinical manifestations are present.

References

• Mayo Clinical & Interpretive Information: Chlamydia IgM and IgG Panel, Immunofluorescence, Serum

Ordering & Collection

Specimen Type

Blood

Collection

3 mL blood in RED TOP tube or GOLD SST

Handling Instructions

Outside Laboratories: Centrifuge sample and transfer serum to a separate plastic vial. Refrigerate serum.

Stability: Refrigerated (preferred): 30 days; Frozen: 30 days; Ambient: Unacceptable.

Reject Due To: Gross hemolysis, gross lipemia.

Quantity

Requested: 0.6 mL serum
Minimum: 0.3 mL serum

Processing

Receiving Instructions

Centrifuge sample and transfer serum to a separate plastic vial. Refrigerate serum.

Sendouts:

• Order Mayo Test: CHLAP.
• Interfaced: Yes.
• If acute and convalescent specimens are submitted, clearly indicate "acute" or "convalescent" on the sample label.

Stability: Refrigerated (preferred): 30 days; Frozen: 30 days; Ambient: Unacceptable.

Reject Due To: Gross hemolysis, gross lipemia.

Misc Sendout

Performance

Lab Department

Sendouts Mayo Lab (RF)(MARF)

Frequency

Performed: Monday - Friday; Report Available: 1-4 days.

Available STAT?

No

Performing Location(s)

Sendout	Mayo Clinic Laboratories (Superior Drive) 800-533-1710 3050 Superior Drive NW Rochester, MN 55901

Billing & Coding

CPT Codes

86631x2, 86632x2

LOINC

6913-8

Interfaced Order Code

UOW2421