Laboratory diagnosis of community-acquired bloodstream infection in therapeutic pathology.

Community-acquired bloodstream infections (CBSIs) occur in the out-of-hospital setting (44%) and increase the overall mortality from bloodstream infections (BSIs) by 7.2% per year. The development of CBSIs depends on both comorbid and polymorbid diseases and the patients' age. The causes of CBSIs are: respiratory, hepatobiliary gastrointestinal and urogenital tracts and dental interventions. The etiology of CBSIs is characterized by the isolation of coagulase-negative staphylococci (CNS) (32%), E. coli (27%). To investigate community-acquired bloodstream infection in therapeutic patients. The study included out-of-hospital patients (n=382). 4.5 ml of blood were taken intravenously into a closed vacuum system in order to obtain a buffy coat of blood, which was put on glasses for microscopy and Petri dishes with blood agar for cultivating under aerobic and anaerobic conditions. Microorganisms were identified by mass spectrometry. Microscopy of blood smears was used for rapid diagnosis of infection in the bloodstream. BSI was diagnosed in 183 (48.0%) out of 382 out-of-hospital patients. The etiology of CBSIs was studied on 297 isolated strains of microorganisms. CBSIs rather often complicated the underlying disease in women and young people. The spectrum of CBSI pathogens included aerobic and anaerobic bacteria and fungi. Gram-positive cocci with the leadership of S.epidermidis (25.7%) were more often isolated among bacteria. 70% of all isolated pathogens grew under anaerobic conditions. CBSIs were characterized by polymicrobiality (33.5%) of two to four different microorganisms in one blood culture; the species of associates of polymicrobial blood cultures are shown. Microscopic examination of blood smears revealed microorganisms in 97.1% of cases, including associations of bacteria with fungi (66.9%). CBSIs occurred after contour plastic, in diseases of the respiratory system, genitourinary system, oral cavity, skin and subcutaneous tissue. Microbiological examination of the buffy coat is an alternative microbiological method of CBSIs diagnosis, which includes microscopy and blood cultivating and has a high diagnostic efficiency (97.1% and 48% respectively). It can become an option for replacing imported blood culture automated systems.

Bloodstream infection in hospital therapeutic patients.

Bloodstream infection (BI) is the cause of high mortality. Hospital bloodstream infection (HBI) complicates hemodialysis, pneumonia, oncohematological diseases. Positive hemoculture obtaining depends on the volume of blood inoculation, the number of blood samples, the incubation time. To test the principles of microbiological culturomics in the diagnosis BI of hospital patients with a therapeutic profile. 848 hospital cardiac patients with suspected BI were included. 10 ml of blood were taken intravenously with a syringe, blood was inoculated into 200 ml of the heart-brain medium (HBM) in an anaerobic bottle. It was incubated for 7 or more days in a thermostat at +37º C. The hemocultures were obtained in 64.3% of cases with paired blood sampling with an interval of 30 minutes whereas an increase in the number of blood samples reduced the effectiveness of obtaining hemocultures to 9.1%. When incubating bottles for more than 7 days there were obtained 200 additional hemocultures containing 239 strains of microorganisms. Episodes of HBI were observed more often in the cases of the circulatory system (77.8%), including infectious endocarditis (IE) (47.0%), rheumatism (22.1%), myocarditis (14.6%). Episodes of HBI occurred more often in men with IE and coronary heart disease, in women - with rheumatism and myocarditis. Patients aged 45-75 were in the group of risk with a probability of complications of HBI up to 73.7%. When examining the blood of 848 hospital patients of cardiological profile HBI was detected in 38.3% of cases. Among clinical isolates gram-positive cocci with a great number S.epidermidis prevailed. Polymicrobial hemocultures (16.3%) were characterized by two and three associates in one blood sample. Among the hematological indicators in HBI there were: leukocytosis, increased ESR, lymphocytosis, decreased hemoglobin; increased values of fibrinogen, CRP, γ-globulin, α2-globulin, low levels of total protein and A/G coefficient. The techniques of microbiological culturomics were used. HBI was diagnosed in 38.3% of the therapeutic patients of cardiological profile. The etiology of HBI was characterized by polymicrobicity in 16.3% of cases. Hematological markers of HBI were identified.

[Brain-heart media for blood cultures.]

When diagnosing bloodstream infection (BI) the culture medium is the basis for growth of microorganisms and obtaining the blood culture. Pancreatic digest from fish meal is the basis of all culture media in Russia. In European countries brain-heart media (BHM) are used for detecting microorganisms in blood. In Russia BHM is not produced. The aim is to work out the formulation and the way of the BHM (broth and agar) preparation in order to improve the efficiency of obtaining blood culture. There were defined the physical and chemical indices and biological parameters of the BHM. The microbiological control of the BHM was carried out by diagnostic study of cardiological patients' blood. On the basis of the developed technique of the brain-heart extraction (BHE) preparation there was created the liquid and agar BHM (LBHM, BHA). The LBHM was poured into bottles which then were filled with the inert gas. The bottles were closed with rubber stoppers and rolled in metal caps became a closed system. Microbiological qualities of LBHM were tested on 260 blood samples and thioglycollate medium (TGM) and LBHM. Aerobic microorganisms grew in LBHM 2,4 times more often than in TGM. The microaerophilic microbes grew in LBHM 3,2 times more often than in TGM. Anaerobic microbes did not show any growth in TGM, (p<0,001). Monomicrobes hemocultures were obtained in LBHM 13,4 times more often than in glucose broth and 2,3 times more often than in TGM, (p<0,001). Polymicrobes hemocultures were obtained in LBHM more often than in TGM (7,3% and 1,7%, respectively). The quality of brain-heart agar (BHA) was tested on 300 blood samples in 5% blood meat-pepton agar (MPA) and BHA in aerobic and anaerobic conditions for both the media. Aerobic microorganisms grew in BHA 2 times more often than in MPA. The microaerophilic microbes grew in BHA 3,6 times more often than in MPA. In anaerobic condition in BHA aerobic microorganisms grew 2 times more often than in MPA and the microaerophilic microbes grew 2,5 times more often than in MPA, (p<0,001). Anaerobic microbes did not grow in MPA. When diagnosing bloodstream infection the BHM (liquid and agar) are able to create the optimal conditions for the increase of the wide range pathogen growth.

[Method for obtaining blood culture while diagnosing bloodstream infection.]

Diagnosing of bloodstream infection (BSI) in outpatients is essential. A large blood volume is required to obtain blood culture (CLSI): 2 sets, 40ml of blood for diagnosing in 95% cases of bacteremia. Molecular-genetic methods can not replace blood culture method, but they accelerate the identification of any pathogen. Culturomics gives a combination of different conditions for isolating microorganisms from a sample and along with their genetic identification. We used the patent method for direct inoculation of buffy-coat from 4,5ml of a venous blood sample and MALDI-ToF identification method. In 382 outpatients examined there were received 183 blood cultures (48,0%), more often among women (65,6%) and young people (74,9%). The causative agents of community-acquired bloodstream infection were aerobes (73,4%), anaerobes (24,2%), fungi (2,4%). The gram-positive cocci were prevailing (51,4%) and the gram-negative rods were isolated rather seldom (9,6%). BSI was monomicrobial (66,5%) and polymicrobial (33,5%). Polymicrobial blood cultures had 2, 3, 4 agents in one blood sample (75,4%, 18,8%, 5,8%, respectively). There were also found combinations of different species of aerobes (47,8%), aerobes with anaerobes (42%). BSI caused complications of the primary disease of the respiratory system, urogenital system and in 100% of cases after plastic surgery. A small blood volume is required for buffy-coat inoculation, the direct agar culture reduces the response time to 2 days, so it makes genetic identification possible on the 2nd day from the moment of blood collection.

[Microflora of the small intestine in patients with perforating duodenal ulcers].

The toxic phase of peritonitis in patients with perforating duodenal ulcers is accompanied with the development of syndrome of redundant bacterial colonization of the small intestine. However, it is less pronounced than in other forms of intra-abdominal infection. The greatest quantitative growth in all the patients is observed among the species of the family of enterobacteria and aerobic Gram-positive bacilli, the bacterial species dominating in the upper part of the intestine in health being the leading etiological agents of intra-abdominal infection in patients with perforating duodenal ulcers. Unlike peritonitis of other etiology strict anaerobic bacteria are found in the small intestine much rarer.

[Levofloxacin susceptibility of Mycobacterium tuberculosis].

Drug susceptibility of 195 M. tuberculosis clinical isolates was tested with the indirect method of absolute concentrations on the Löwenstein-Jensen medium. 151 and 44 M. tuberculosis strains were isolated from patients with respiratory tract tuberculosis and tuberculosis of extrapulmonary localization respectivily. The resistance of the isolates to the main and reserve antituberculosis drugs amounted to 79.5%, including 62.1% of the isolates with multiple drug resistance. Levofloxacin was used in a concentration of 10 mcg/ml. The resistance to levofloxacin was detected only in 4 isolates from the patients with respiratory tract tuberculosis (2.05%), whereas the resistance to ofloxacin amounted to 11.8%.

[Improvement of microbiological diagnosis of dysbacteriosis]. / Sovershenstvovanie mikrobiologicheskoi diagnostiki disbakteriozov.

The study was undertaken to improve transport and selective culture media and a testing scheme for dysbacteriosis. Great emphasis is laid on methods for isolating and identifying the nonclostridial anaerobes which are the major component of the normal human intestinal microflora. The following media were proposed: a) a sterility-checking-up medium, hemin, vitamin K1, cysteine, and twin 80 was for transportation of samples to a laboratory; b) anaerobic blood-containing agar with selective additives (kanamycin and bile) for isolation of bacteroids; c) a propionic acid-containing medium for isolation of bifidobacteria; d) a acetic acid-containing medium for isolation of lactobacteria. The use of the above culture media, microanaerostats, and three-component gas mixture substantially enhanced the efficiency of microbiological diagnosis for intestinal dysbacteriosis.

[Infections caused by non spore-forming anaerobic bacteria]. / Sostoianie problemy infektsii, vyzyvaemykh nesporoobrazuiushchimi anaérobnymi bakteriiami.

Pyo-inflammatory diseases continue to be one of the topical problems of modern medicine. Their etiological agents are opportunistic microorganisms among which non spore-forming anaerobes are prevalent in the normal microscopic flora. They cause a pathological process when the body's immunity is decreased. The authors consider the biological features of this group of bacteria, epidemiological and pathogenetic aspects, the problems of laboratory and clinical diagnosis of non clostridial anaerobic infection and outline immediate steps to be taken to solve the problems.

[Progress and perspectives in the study of non-clostridial anaerobic infection of female genitalia]. / Dostizheniia i perspektivy v izuchenii neklostridial'noi anaérobnoi infektsii zhenskikh polovykh organov.

The paper summarizes the results from 15-year studies of non-clostridial anaerobic infection in obstetrics and gynecology. The authors show that strict non-spore-bearing anaerobic microbes are prevalent in the etiological pattern of pyoinflammatory diseases of the female genitals, present the basic pathogenetic features of the development and clinical signs of anaerobic infections. The present-day principles of diagnosis and treatment of these diseases are given. Prospects are shown for further studies of non-clostridial anaerobic infection in obstetric and gynecological care.

[Current problems of tropical medicine (based on materials of the Military Medical Conference of Countries of the Asian-Pacific Ocean Region)]. / Aktual'nye problemy tropicheskoi meditsiny (po materialam voenno-meditsinskoi konferentsii stran Aziatsko-Tikhookeanskogo regiona).

The scientific messages presented at the 3rd Asia Pacific Military Medical Conference are scrutinized. The encounter of about 200 military doctors from 14 countries of the appropriate region was heed in Jakarta in 1993, hosted by the Indonesian Army and sponsored by the United States Army Pacific Command. The Conference comprises 3 symposia on: military medicine and humanitarian assistance; malaria and parasitic diseases of military relevance; protecting the troops during tropical deployments. There were 53 reports in all, the leading ones belonged to American authors. Detailed discussions concluded every working day. In the whole the Conference reminded a regional seminar of military doctors in the shape of continuing medical education. The participants got qualification eredits in the field of tropical medicine.

[The use of eubiotics for the treatment of bacterial vaginosis]. / Primenenie éubiotikov dlia lecheniia bakterial'nogo vaginoza.

The study was concerned with the problem of the treatment of bacterial vaginosis. To correct the dysbiotic condition in the vagina, a two-stage procedure was applied. The first stage was aimed at the provision of the normal physiological condition of the vaginal medium and mucosa and the second stage was aimed at the provision of the normal microbiocenosis. At the second stage biological preparations such as lactobacterin, acylact, bifidumbacterin and bifidin were used. The recovery was stated in 88.4 per cent of the cases after a single treatment course with the use of the biological preparations. In 4.7 and 2.1 per cent of the cases the recovery was stated after two and three treatment courses respectively. In 4.7 per cent of the cases the treatment was of low efficacy. The use of the eubiotics for the treatment of bacterial vaginosis was shown to be highly efficient.

[The etiological diagnosis of nonclostridial anaerobic organic infection of the hepatobiliary system in military medical institutions]. / Etiologicheskaia diagnostika neklostridial'noi anaérobnoi infektsii organov gepatobiliarnoi sistemy v voennykh lechebnykh uchrezhdeniiakh.

The results of B-bile bacterial examinations of patients who had undergone operations on biliary tract for acute or chronic cholecystitis in the military medical institutions of the USSR and the USA were retrospectively compared. Distinctive and similar features were revealed. The leading role of bacteroids, anaerobic found bacteria and clostridia was ascertained during the studies of etiological structure of anaerobic biliary infection. As for nonclostridial anaerobic infection of biliary tract, the polymicrobiotic process of aerobic and anaerobic associations is more typical. The centralization of bacteriological examinations in specialized "anaerobic" laboratory may improve the efficiency of microbiological diagnostics of nonclostridial anaerobic infection.