Chlamydia psittaci Antibodies IgG, IgA, IgM

General Information

Chlamydia is an intracellular, prokaryotic (non-nucleated) unicellular parasite, 0.2-1 nm in size, which is characterized by the characteristic features of both bacteria and viruses:

Characteristics of bacteria:

• synthesizes RNA and DNA
• has a cell wall
• A membrane characteristic of gram-negative bacteria
• Sensitive to cyclin type antibiotics

Characteristic features of the virus:

• reproduces only in living eukaryotic (nuclear) cells
• It does not have the ability to synthesize ATP, so it receives it from the host organism

According to the classification, 4 families of chlamydia are distinguished, of which the family Chlamydiaceae stands out for its pathogenicity to humans. 2 genera of this family are distinguished:

• Genus Chlamydia, the most important representative of which is C. trachomatis;
• Gvari Chlamydophila – C. pneumoniae, C. psittaci, C. cattle, C. abortus and others.

Psittacosis (also known as ornithosis) is an infection caused by C. psittaci. The main source of infection is birds, especially parrots, as well as domestic animals. The infection is transmitted to humans through the respiratory secretions and excrements of infected animals or birds. Human-to-human transmission is rare, and in this case the disease is more severe.

Psittacosis is an occupational disease for staff working in zoos and pet stores, for farmers.

The incubation period of psittacosis (ornithosis) is 5-14 days (very rarely it may last more than a month).

Three clinical forms of the disease develop:

• Multisystem (disseminated) form – characterized by meningitis or encephalitis associated with pneumonia
• The type of pseudo-influenza (pseudo-influenza) is characterized by the characteristic course of influenza - chills and fever.
• Pulmonary form or atypical pneumonia - respiratory infection, begins with fever, chills, cough, deterioration of the general condition, muscle, joint, chest and headache pain, shortness of breath. Objective research data is scarce. The disease progresses over months.

The diagnostics of psittacosis is made on the basis of epidemiological, clinical, radiological and laboratory-serological data.

When conducting laboratory research, it is recommended to examine two samples: one - taken in the acute phase. The second - with an interval of 2-3 weeks.

Patient preparation - It is better to conduct the research on an empty stomach

Research material -  Venous blood

Referral norms:

1. psittaci IgG: <1/16
2. psittaci IgM: <1/10
3. psittaci IgA: <1/20

Interpretation of results

Serological diagnostics of psittacosis requires an increase in IgG antibody titer or conversion from negative to positive between the acute and convalescent phases.

The lack of IgG antibodies indicates an insufficient immune response to the bacterial agent.

The detection of IgM antibodies usually indicates an acute process, however, IgM antibodies are characterized by cross-activity with C. Pneumoniae and C. Trachomatis, so it is necessary to determine all three types of antibodies - IgG, IgM, IgA - and interpret the indicators together with clinical data in dynamics.

A negative level of antibodies does not rule out the disease, but may indicate immunodeficiency.