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Lab Manual for Moffitt-Long and Mount Zion

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Chlamydia Antibody (MIF)

Item Value
Approval req'd? No
Available Stat? No
Test code CPNI (C. pneumoniae (TWAR)), CTRI (C. tranchomatis), CPSI (C. psittaci)
Test group Chlamydia
Performed by Focus Diagnostics via Quest
Sendout? Yes
Method Micro-immunofluorescence assay (MIF)
Collection Instructions Request MUST specify the single organism sought
Container type Gold top or Red top
Amount to Collect 2 mL blood
Sample type Serum
Preferred volume 1 mL serum
Min. Volume 0.25 mL serum
Processing notes Refrigerate sample. Enter the appropriate test code for the organism requested:
Code Organism
CPNI Chlamydia pneumoniae
CTRI Chlamydia trachomatis
CPSI Chlamydia psittaci
Units Titer
Normal range
Antibody Negative Titer
IgG <1:64
IgA <1:16
IgM <1:10
Synonyms LGV; Parrot fever; Psittacosis; congenital infection; prenatal infection
Stability Room temperature 1 week, refrigerated 2 weeks, frozen 1 month.
Turn around times Test run 6x per week. Turnaround time 5-6 days.
Additional information IgG, IgA and IgM antibody tests are performed for each organism requested

The immunofluorescent antibody test is more sensitive than CF and is the best serologic test for diagnosing chlamydial infection, although seroconversion may be delayed, as with the CF test. Due to the prolonged incubation period often seen in acute disease, the usual criterion for acute infection of a 4 fold rise in titer may not be demonstrable.

In patients infected with C. pneumoniae (TWAR), 70% of whom develop IF antibody (compared with 50% for CF) a single IgM titer > 32 or an IgG titer > 512 suggests acute infection.

Because antibody persists from prior exposures, levels (even of IgM) are often unhelpful in the diagnosis of urethritis or cervicitis in adults, although very high titers suggest invasive disease, e.g., salpingitis, epidydimitis or proctitis. Transplacental passage of maternal antibody may interfere with serodiagnosis of acute infection in infants.
CPT coding 86632-90, 86631-90 x2 for each organism tested.
Last Updated 10/25/2013 12:18:42 PM
Entry Number 181

If you have additional questions regarding this test, please call: 415-353-1667

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