Pneumoclamidiosis

The pneumoclamidiosis - the disease concerning anthroponoses, is characterised by the acute beginning, a fever and a primary lesion of a respiratory organs.

Aetiology. The originator - Chlamydia pneumoniae. For difference from other clamidioses it suggested to name this disease a pneumoclamidiosis. The disease-producing factor is described rather recently. In 1965 on an island Taiwan in a stuff taken from a conjunctiva of the sick child, has been secured the microbic agent named TW 183, then in the USA in 1983 from pharyngeal washout of the patient the ARD is secured infectious agent AR 39. After an establishment of identity of these two originators it began to be called in the literature as strain TWAR. Detailed studying of its properties has allowed to carry strain TWAR to chlamydias.

This new kind of chlamydias has received name Chlamydia pneumoniae. It possesses properties, characteristic and for other chlamydias, also is an intracellular parasite, however at a submicroscopy intracellular includings on morphology differed from includings which are formed at intracellular reproduction of other chlamydias a little. DNA was specific also, only about 10 % was the general with other chlamydias. In a complement-fixation test gives cross-reactions with an antigen from chlamydias Ch.psittaci, Ch. trachomatis, but in reaction of a microimmunofluorescence it from them is essential differs. Though Ch. pneumoniae for the first time it is secured at the patient with a lesion of eyes, this chlamydia does not play some an essential role in an aetiology of conjunctivitises. Basically it is bound to a lesion of a respiratory organs. So, at inspection sick of an acute pneumonia the positive reactions specifying in a contamination by this chlamydia, were taped in different years from 6 to 17 % to number surveyed, and at a bronchitis - from 3 to 8 %. The chlamydia in an external environment is not so steady. At 4°С in medium for transportation of a stuff it remains about 24 hours. It is inactivated at repeated freezing and thawing. As well as other chlamydias it is sensitive to Tetracyclinums and erythromycin and it is refractory to Penicillinum, ampicillin, Sulfanilamidums. Cultivate on an educing chicken embryos and on cellular cultures. Has only one serological variant.

Epidemiology. An infection contamination source is the sick human. The transmission of infection is carried out air-drop by. The pneumoclamidiosis meets not only in the form of sporadic cases, but also in the form of epidemic flashes, especially in the organised collectives. So, in Finland in the season C 1977 for 1985 4 epidemic flashes of a pneumonia (the case rate fluctuated from 60 to 84 on 1000) were observed. The nature of a pneumonia with the help a complement-fixation test and microimmunofluorescence reactions has been deciphered. Basically military men of young age were ill. Epidemic flash was tightened for some months, in one of garrisons it lasted from July till December, another proceeded from January till June, with peak in April-May. Possibly, it is bound to a long incubation interval. Communication with a frigorism was absent. At observation of civilians the greatest case rate was among persons at the age from 20 till 49 years.

Pathogenesis. The pneumoclamidiosis pathogenesis is studied insufficiently. Infection atriums are respiratory tracts. The primary lesion of bronchuses and lungs testifies to changes in range of infection atriums as it is observed and at an ornithosis. However unlike an ornithosis in process mucosas of the top parts of a respiratory tract, a pharynx, adnexal sinuses of a nose are involved. Further chlamydias inpour into blood, cause symptoms of the general intoxication and a lesion of pots. It is possible to admit reproduction of chlamydias in an endothelium of pots, they can damage and an endocardium. As well as at other clamidioses the long persistence of chlamydias in an organism is observed. It causes a chronic lesion of a respiratory organs in the form of a bronchial asthma, a chronic asthmatic bronchitis, vascular disturbances, can is long to remain and antibodies. In a pathogenesis stratification of a secondary bacteriemic infection contamination matters. Intensity and duration of immunodefence remain not studied.

Symptoms and flow. The incubation interval precisely is not established, however prolixity of epidemic flashes speaks about a long incubation interval. The pneumoclamidiosis can proceed in acute and chronic forms. Acute to brake proceeds in the pneumonic, nasopharyngeal and asymptomatic (latent) form. The chronic pneumoclamidiosis shows in pulmonary (a bronchial asthma, an asthmatic chronic bronchitis) and cardiovascular forms (endocarditises, a coronary disease), probably long asymptomatic carriage of chlamydias, and also a combination of a clamidiosis to bacteriemic infectious diseases.

Pneumonic forms begin acutely, the body temperature raises to 37,5-39C°, there are signs of the general intoxication, a pain in muscles, at a part of patients of a pharyngalgia, a stethalgia. Early there is a dry tussis, is is rather rare - tussis with a small amount of a mucous sputum. A dyspnea, dry and wet rhonchuses are auscultated. In most cases (about 80 %) process grasps not one lobe, usually the pneumonia happens bilaterial. Pharyngitis signs are observed at 20-25 % of patients. Clinical physical signs of a lesion of lungs keep 7-10 days. Radiological changes in lungs disappear in 12-30 days. The augmentation of cervical lymph nodes (25-30 %) often enough becomes perceptible. At research of peripheric blood, unlike an ornithosis, expressed enough leukocytosis (12-20 thousand in 1 microlitre) neutrophilic character becomes perceptible.

At some sick (10-15 %) clinical and radiological signs of a pneumonia are absent, become perceptible only a lesion of the top respiratory tracts in the form of a rhinitis and a pharyngitis. These implications of disease pass in some days.

The asymptomatic carriage can proceed about one year and more. During first time it is possible to consider it inapparent, then it passes in the latent. This carriage can be observed both without previous clinical implications (initially-latent), and after disappearance of all clinical and radiological changes (again-latent). The long persistence of chlamydias can cause appearance of relapses (in 2 weeks and in more remote terms after body temperature normalisation), occurrence of chronic forms of disease and, at last, has epidemiological value. The culture of chlamydias can be secured from nasopharyngeal washouts even in 12 months after disappearance of clinical implications of an acute disease. Thus serological tests with clamidian antigens at such carriers can remain negative.

Chronic pneumoclamidiosis. At a part of patients already in the acute season accurately expressed bronchospasm is taped. At a long persistence of chlamydias the chronic asthmatic bronchitis is gradually formed. An allergization of an organism antigens of chlamydias and the remaining originator promote bronchial asthma development. Communication of a bronchial asthma with infection contamination Ch. pneumoniae now it is proved on big enough number of observations. In bronchial asthma formation it is impossible to exclude a role of a secondary bacteriemic infection contamination completely. The important problem is the further studying of various variants of clinical flow of chronic diseases of the lungs caused by a pneumoclamidiosis.

The chronic lesion of cardiovascular system at a pneumoclamidiosis is studied less. As the rare clinical form it is described clamidian an endocarditis, proceeding it is long and it is serious enough. Enriching has come after treatment by preparations of a tetracycline number. Similar endocarditises on flow were observed as the rare form of an ornithosis.

Observations of last years have taped communication of changes of coronary pots C clamidian an infection contamination. In particular, it is shown, that at persons with coronary disorders antibodies to Ch are much more often taped. pneumoniae. Suppose possibility of participation of a pneumoclamidiosis in an atherosclerosis genesis. This problem demands also the further accumulation of observations.

One of the most frequent forms of infection contamination Ch. pneumoniae the long asymptomatic persistence of chlamydias in an organism is. It is established, that at 70-90 % infected process proceeds latently.

The diagnosis and the differential diagnosis. Pneumoclamidiosis recognition represents appreciable difficulties. The semiology of pneumonic forms is similar to an acute pneumonia of other aetiology. During epidemic flash diagnostics is facilitated after decoding of the first cases of a pneumonia as pneumoclamidiosis flashes proceed some months. Diagnostics of sporadic cases is more difficult. The combination of physical signs of a pneumonia to a lesion of the top respiratory tracts (rhinites, pharyngitises) is observed at many pneumonia complicating an ARD.

At revealing of positive takes a complement-fixation test with any clamidian antigen (this reaction nonspecific and consequently to judge a concrete clamidian infection contamination on it is impossible) it is necessary to differentiate an ornithosis and a pneumoclamidiosis.