Ornithosis( Psittacosis) - Causes, symptoms and treatment. MF.
Jun 06, 2018
Acute zooanthroponous bacterial infection belonging to the group of chlamydial infections, with an air-droplet transmission mechanism( possible contact-household and fecal-oral), characterized by a lesion of the pulmonary and nervous systems, taking place against the background of hepatolienal, febrile and general toxication syndromes.
For the first time, the disease was registered from parrots - hence its original name "psittakos"( psittakos - parrot), but as soon as they saw an infectious connection from other birds, psittacosis had a second name - ornithos( bird).
Pathogen of ornithosis
Pathogen of ornithosis under the
microscope Pathogen - Chlamydophila psittaci is an obligate intracellular parasite and has some structural peculiarities that cause the course of the disease:
• multiplies inside the affected cells;
• Are able to form an L-form exciter that is devoid of a partially or completely cell wall, which allows it not to die and retain its virulence for a long time, even when exposed to damaging factors( temperature, antibiotics, phagocytosis, etc);
• The causative agent can be in two forms - the elementary and reticular bodies, this is important in the appointment of treatment: the elementary bodies are spore-like because of the presence of a strong shell which makes the pathogen not sensitive to antibiotic therapy, and in this life cycle the pathogen is outside the cell,and under unfavorable conditions, the division is suspended with a decrease in the synthesis of the main membrane protein and an increase in the synthesis of the heat shock protein( for this causative agent this protein is exoticaotherwise) - it causes the synthesis of pro-inflammatory cytokines, which in turn plays a role in the formation of chronic infection and long-term persistence( staying) of the pathogen with the formation of infertility in women. Reticular bodies are an intracellular reproducing form that is sensitive to antibiotics. It is during the reticular form that the pathogen divides inside the infected cells, resulting in the formation of intracellular inclusions - microcolonies of chlamydia.
• Exotoxin( heat shock protein) and endotoxin( lipopolysaccharide membrane).
• Tropism( selective lesion) to the cells of the cylindrical epithelium of the respiratory and urogenital tracts( predominantly), alveolocytes, vascular endothelium, endocardium, SMF( the system of mononuclear phagocytes is a physiologically protective cell system, which includes: histiocytes of connective tissue, Kupffer cells of the liver( stellatereticuloendotheliocytes), alveolar macrophages of the lungs, macrophages of lymph nodes, spleen, bone marrow, pleural and peritoneal macrophages, osteoclasts of bone tissue, microgluenerve tissue, synoviocytes of synovial membranes, Langerhaus skin cells, pigmentless granular dendritic cells).With the defeat of this system( CMF), an IDS( immunodeficiency state) is formed.
The causative agent is relatively stable in the external environment:
• so at room temperature, the pathogen remains on average up to 2 days, on the shell - 3 days, in the feces of birds - up to 4 months.
• well tolerate negative temperatures: at "-20 ° C" it persists for half a year, at "-75 ° C" - for a year or more;
• low temperatures are detrimental: at 60 ° C the pathogen dies within 10 minutes, at a lower temperature the death of chlamydia occurs almost instantaneously.
• Disinfectants have an inactivating effect both physically and chemically: UV, ether, formaldehyde, 0.5% phenol, 2% lysol, 0.1% potassium iodide, 0.5% potassium permanganate, 6% peroxide solution - destroy the pathogenin 2 days;Within 10 minutes the causative agent perishes by the action of 0.5% chloramine solution, and 2% chloramine solution destroys the pathogen within a minute.
Susceptibility is high, without age and sex restrictions, but there is a greater tendency among middle and older ages, but children are no exception. The prevalence is ubiquitous, the incidence is recorded in the form of sporadic cases, as well as group, industrial and family outbreaks.
Causes of infection with ornithosis
The source and reservoir( keeper) of infection are various species of wild, synanthropic ornamental and domestic birds in which ornithosis proceeds as a carrier or an acute intestinal infection. Also, cases of infection of health workers with care of sick people are registered, so a person can also be a source. Ways of transmission of infection - contact-household( ie when infecting household items with biological fluids of animals), aerogenic( airborne) and fecal-oral( with food contamination).
Source of infection with ornithosis
Symptoms of ornithosis
Before talking about symptoms, it is necessary to be able to recognize infected birds in order to avoid, or to minimize the level of contact with them. In this case, one should know:
1) - epidemic danger is represented by the families of parrot and bluebirds, as well as crows.
2) - bird bird ornithosis either does not manifest itself in any way and reduces only to carriage, or manifests itself in the form of rhinitis / diarrhea / adynamia( minimization of motor activity) / refusal to eat / sticking of feathers.
3) - infected birds excrete pathogens with feces and nasal secretions.
4) - transmission of the pathogen among birds is possible for two or more generations.
Symptoms of ornithosis
Like any infectious disease, ornithosis begins with the incubation period - the time from the onset of the introduction of the pathogen and to the first clinical manifestations. It lasts from 7 to 25 days, but more often - 2 weeks. This period coincides with the phase of introduction and multiplication of the pathogen at the site of the entrance gates( in the epithelium of the conjunctiva, the mucous membranes of the respiratory and urogenital tracts).As the pathogen multiplies, the infected cells die with a new dose of the pathogen and its toxins, followed by the formation of bacteremia and toxemia - but this already indicates the beginning of a period of clinical manifestations.
The period of clinical manifestations can begin with both specific symptoms( to be described below) and prodromal symptoms lasting 3-5 days in the form of malaise + general weakness and weakness + loss of appetite and nausea + arthralgia. During this period, the cells of target organs are infected( especially SMF), an immunodeficiency state is formed, autoimmune reactions are formed, the organism is sanitized from the pathogen and, as a consequence, the persistent persistence of the pathogen in various cellular stages( in the form of reticular /in macrophages, in the form of elementary bodies in intercellular spaces, in L-forms in infected cells);activation of opportunistic microflora( mycoplasma, herpesvirus, candida) and / or formation of secondary bacterial infections. Since the SMF includes an impressive number of organs, the symptoms of lesions can be very diverse - with the involvement of joints, lymph nodes, liver, spleen, endothelium of capillaries, endocarditis, CNS, etc. In these affected organs, activation of free radical oxidation with tissue damage by aggressive forms of OA and macrophage release of proinflammatory cytokines( IL-1 and TNF) occurs, serous inflammation is formed, and due to the migration of macrophages and lymphocytes, multiple granulomas are formed which subsequently undergofibrotic sclerotic transformation in the affected organs.
T.k mainly affects the respiratory tract cells, specific symptoms are formed:
• acute onset with a rise in temperature to 39-40 ° C and general toxication symptoms;
• chest pain;
• myalgia( muscle pain) and arthralgia( joint pain);
• nausea and vomiting;
• sore throat;
• injection of vessels of sclera and conjunctiva, hyperemia of the face, appearance of spotted-papular or rosaolous rash, nosebleeds - are explained by the pathogenicity of the pathogen to the vascular endothelium;
• catarrhal symptoms( runny nose, nasal congestion, perspiration in the throat, hyperemia of the mucous membrane of the oropharynx) - are weakly expressed;
• symptoms of lung damage appear on the 3-5th day of the disease, in the form of dry cough and pain in the chest, 2-3 coughs become productive with the discharge of mucopurulent sputum and blood veins - this indicates the possible development of ornithous pneumonia;
• By the end of the first week of the disease, the majority of patients are suffering from liver disease;
• Signs of neurotoxicosis: headache, insomnia, lethargy, adynamia, depressive state and euphoria often change, there may be signs of meningitis( false-positive symptoms of meningitis);
Ornithosis can occur not only in the form of pneumonia, but also in influenza-like form, typhoid-like and meningic. With influenza-like form, the general intracellular symptoms predominate;at typhoid-like - hepatosplenomegaly and neurotoxicosis proceeding against the background of fever remitting type;when the meningeal form - quite well expressed meningeal symptoms( rigidity of the occipital muscles, symptoms of Brudzinsky and Kering).Regardless of the form, even during the recovery period( which lasts about 3 months), asthenia is lasting for a long time with a sharp decline in work capacity, fast fatigue, hypotension, vegetative-vascular changes( acrocyanosis, chilliness of limbs, palmar hyperhydrosis, tremor of the eyelids and fingers).
Analyzes for ornithosis
Diagnosis is based on clinical and epidemiological data: pneumonia, no acute inflammatory response from the blood, contact with the bird, group morbidity is possible. The diagnosis is confirmed by the following tests:
• bacterioscopy of sputum smears stained according to Romanovsky-Giemsa;
• Serological methods: RIF( immunofluorescence reaction) to determine the antigen of chlamydia;The RCC( complement fixation reaction) is directed towards the detection of antigen-neutralizing antibodies, namely, they look at the increase in titer of antibodies in paired sera, the positive reaction is an increase in the titer of 1:16, 1:32 and higher;Serological methods are aimed at detecting IgM( immunoglobulins of this class indicate an acute period of the disease) - appear after 5 days from primary infection and reach a maximum of 1-2 weeks, and disappear after 2-3 months, but they are not formed during reinfection and reactivation;IgA - secretory immunoglobulins, which begin to be synthesized after 2 weeks, decrease to 2-4 months, are also formed during reinfection and inadequate treatment, with effective therapy - their number decreases;IgG - appear after 15-20 days and can persist for several years.
• In case of suspected ornithosis pneumonia, physical methods( auscultation, percussion) are used to detect shortening of percussion sound, weakened or hard breathing, uninvited crepitation or small bubbling rales in the lower parts of the lungs, and by the end of the first week, pleural friction noise is often heard;And for a more complete picture of pneumonia, X-ray diagnostics are used, which shows a unilateral lower-lobe pneumonia, which can be interstitial, small-focal, large-focal or lobar;And on the X-ray, the enlargement of the lung roots, the enhancement of the pulmonary pattern and the expansion of the bifurcation lymph nodes are noted.
• On the SSS side note - the tendency to bradycardia, hypotension, pulse lability, possibly muffling heart sounds, systolic murmur and ECG signs of diffuse heart damage.
• With meningic symptoms, a spinal puncture is prescribed that shows: mild lymphocytic cytosis( 300-500 cells per 1 μl), moderate protein increase.
• In UAC - lakopenia and lymphocytosis, increased ESR up to 40-60 mm / h;Leukocytosis is possible with the deposition of a secondary bacterial infection.
Treatment of ornithosis
Treatment is complex, and is represented by etiotropic, pathogenetic and symptomatic methods with mandatory monitoring of clinical and laboratory data.
Etropic therapy is the administration of drugs designed to destroy the pathogen and, in this respect, antibiotics from the group of macrolides, fluoroquinolones and tetracyclines are effective( for children, macrolides are used more often, since fluoroquinolones have been used since 12 years, and tetracyclines have been used since 8).There are different regimens for prescribing antibiotics, but recently the effectiveness of the following prescribing scheme has been proven: azithromycin at 10 mg / kg / day at 1 intake at 1, 7 and 14 days of treatment. Azithromycin is the drug of choice, but other antibiotics from the macrolide group also have excellent antichlamydia activity - clarithromycin, spiramycin, roxithromycin, josamycin, medikamycin and erythromycin( antibiotics are indicated as the efficiency decreases).In acute form - antibiotics prescribed in the age of dosage within 10-14 days. In chronic course - apply pulse therapy, which consists in the appointment of 2-3 courses of antibiotic therapy for 7-10 days at intervals of a week, as well as with the change of antibiotics. To help with etiotropic therapy, immunomodulators and immunostimulants are prescribed - interferon, viferon, cycloferon, anaferon, thymoline, thymogen, polyoxidonium, lycopide. But these drugs are prescribed only under the control of the immunogram.
Pathogenetic therapy is reduced to the purpose:
- cytokine preparations( leukinophorone, roncoleukin)
- probiotics and prebiotics( bifiform, linex, etc.) for the prevention of dysbacteriosis
- multivitamins, vitamin-mineral complexes, antioxidants, plant adaptogens, metabolites, antihistamines, protease inhibitors, vasoactive drugs - all this is used according to the indications with the appropriate clinic
Symptomatic treatment of :
- with dry cough-cough, sinecode, stopussin, tussupreks, pakseladin, libeksin. But when prescribing these drugs, you need to consult a doctor or know an anamnesis, because some of these drugs are central and can depress the effect of not only the cough but also the respiratory centers.
- with mild cough - mucolytics( bromhexine, ambroxol, ATSTS, mukaltin, thoracic gathering)
- appointment of antipyretic and cardiac glycosides - according to indications.
Post-infectious immunity is unstable and possibly re-infected.
In the period of re-incarceration, an infectious disease specialist and pediatrician( therapist) should be examined at 1, 3 6 9 12 and 24 months after recovery, using additional ELISA, PCR and chest X-ray at 6, 12, 18, 24 months. Consultation of other specialists - on indications. Terms of incapacity for work - 7-10 days for influenza-like form, 20-40 days - if pneumonia occurs, in case of prolonged and chronic course, the period of incapacity for work is established by the commission.
Complications of ornithosis
Meningitis, thrombophlebitis, hepatitis, myocarditis, thyroiditis, pancreatitis. But the main cause of complications is the formation of fibrosis-sclerosing changes in the affected organs.
Aerosol vaccination is still under development, at the moment only nonspecific prevention is available - restriction of contact with birds, veterinary supervision, isolation of patients with ornithosis, disinfection of sputum from patients.
Therapist doctor Shabanova I.Е.