Mycoplasma pneumoniae complement fixation test

There are 15 species of mycoplasma. The main pathogens are M. pneumoniae (MP), U. urealylicum, M. hominis and genital mycoplasma ( M.genitalium). Mycoplasma pneumoniae mainly causes upper respiratory tract infection, tracheobronchitis and mycoplasmal pneumonia. Mycoplasma hominis, Ureaplasma urealyticum and genital tract mycoplasma are pathogens causing genital tract diseases. Ureaplasma urealyticum can cause non-gonococcal urethritis, testicular epididymitis, chronic prostatitis, cervicitis, vaginitis, etc., can also lead to urinary tract stones. Ureaplasma urealyticum can also infect the fetus through the placenta, causing spontaneous abortion, premature delivery, stillbirth and low birth weight fetuses. It can also attach to the surface of the sperm, causing infertility. Human mycoplasma can cause pelvic inflammatory disease, salpingitis, and can also cause neonatal infection. Mycoplasma of the genital tract may cause urethritis and pelvic infections.

Basic Information

Specialist classification: Infectious disease inspection and classification: pathogenic microorganism inspection

Applicable gender: whether men and women apply fasting: fasting

Analysis results:

Below normal:

Normal value:

Above normal:

Negative means normal and not infected with mycoplasma.

Positive indicates mycoplasma infection.

Tips: Mycoplasma pneumoniae cross-reacts with Mycoplasma genitalium and Legionella pneumophila, and false positives can occur in certain neurological diseases and acute pancreatitis. Normal value


Clinical significance

Abnormal results:

The complement-binding antibody began to rise from 7 to 9 days after infection, reached a peak at 3 to 4 weeks, and was positive in about 90% of patients. A single serum titer > 1: 64 ~ 128 or double serum increased by more than 4 times, has a diagnostic significance.

Need to check the crowd:

Patients with urinary calculi, infertility, fever, chronic cough, etc. should perform this test.

Positive results may be diseases: mycoplasma pneumonia, mycoplasma urinary tract infection precautions

Requirements for inspection:

1. Mycoplasma pneumoniae cross-reacts with genital mycoplasma and Legionella pneumophila, and false positives may occur in certain neurological diseases and acute pancreatitis.

2, sputum, especially only tracheal aspiration and secretion culture to isolate the Mycoplasma pneumoniae can be diagnosed.

3. Most patients with pneumonia-only progenitors have mild symptoms. The initial manifestations are upper respiratory symptoms and no signs in the chest.

Preparation before inspection:

1. There is no sign of pneumonia in a fever of 39 degrees or more and 2 to 3 days, but it is necessary to consider whether this test should be carried out.

2. Go to the patient's sputum for examination.

Not suitable for people:

Those who do not have an indication for examination should not do this check.

Inspection process

This test is a serological test, which is the most commonly used detection method for the diagnosis of pneumonia infection, such as complement fixation test, indirect fluorescent antibody assay, indirect hemagglutination test, enzyme-linked immunosorbent assay (ELISA) and growth inhibition test. The enzyme-linked immunosorbent assay is the most sensitive and the immunofluorescence method is specific. The serological method can directly detect the pneumoniae antigen in the specimen for rapid clinical diagnosis.

Not suitable for the crowd

No taboos.

Adverse reactions and risks

Generally no complications and harm.