Biomedical subjects
Publications and source records attributed to P Huovinen.
The telithromycin susceptibility of 210 erythromycin-resistant pneumococci was tested with the agar diffusion method. Twenty-six erm(B)-positive isolates showed heterogeneous resistance to telithromycin, which was manifested by the presence of colonies inside the inhibition zone. When these cells were cultured and tested, they showed stable, homogeneous, and high-level resistance to telithromycin.
The prevalence and mechanisms of macrolide resistance among 1,007 clinical pneumococcal isolates collected in Finland were investigated. Of these, 217 (21.5%) were resistant to erythromycin and 11% to clindamycin. Among the erythromycin-resistant isolates, mef(E) was present in 95 isolates (44%), mef(A) was present in 12 isolates (6%), and erm(B) was present in 90 isolates (41%). A double mechanism, mef(E) and erm(B), was detected in five isolates (2%). Ribosomal mutation was detected in 14 (6%) macrolide-resistant isolates in which no other determinant was found. Based on the telithromycin MICs, two groups of isolates were formed: 83.3% of the isolates belonged to a major group for which the telithromycin MIC range was < or =0.008 to 0.063 microg/ml, and 16.7% belonged to a minor group for which the telithromycin MIC range was 0.125 to 8 microg/ml. All except three isolates in the minor population carried a macrolide resistance gene.
The aim of our study was to evaluate antimicrobial use in dogs and cats in Finland. Information on veterinary prescriptions was gathered from University Pharmacies (n=17) over a one-month period, April 2001. A total of 2719 prescriptions for veterinary use were delivered, of which the majority were for dogs (70%, n=1898) and cats (14%, n=384). The most prescribed therapy group was per-oral antimicrobial agents (53%, n=1449), of which 16% (n=237) were medicines approved for humans. The most commonly used substances for dogs and cats were betalactams, 66% and 78%, respectively. The proportion of fluoroquinolones was 3-5%. The average duration of the treatment periods was 10 days with the exception of treatment of cats with macrolide-lincosamides, where the mean period was 20 days. Indication was mentioned only in 37% of the prescriptions.
A database of the prescriptions of antimicrobial drugs for the treatment of common infectious diseases in dogs at the Finnish Veterinary Teaching Hospital was searched to determine to what extent national guidelines were being followed. Twenty-two per cent of 5918 dogs were treated orally with antimicrobial drugs. The most commonly used drugs were beta-lactams (49 per cent) of which cephalexin and amoxycillin-clavulanate were most widely prescribed. The usage of fluoroquinolones was only 2.8 per cent. The prescription of antimicrobials for pyoderma was contrary to Finnish guidelines, but the use of cephalexin or amoxycillin-clavulanate as first-line drugs instead of macrolides or lincosamides or trimethoprim-sulphonamides was acceptable because of the presence of resistance by canine staphylococci. The drug most commonly used to treat acute urinary tract infections was trimethoprim-sulphonamide, in agreement with the guidelines. Antimicrobial drugs were used excessively after surgical procedures, and for treating acute gastrointestinal disturbances and small wounds and traumas.
Elliptic flow and two-particle azimuthal correlations of charged hadrons and high-p(T) pions (p(T)>1 GeV/c) have been measured close to midrapidity in 158A GeV/c Pb+Au collisions by the CERES experiment. Elliptic flow (v(2)) rises linearly with p(T) to a value of about 10% at 2 GeV/c. Beyond p(T) approximately 1.5 GeV/c, the slope decreases considerably, possibly indicating a saturation of v(2) at high p(T). Two-pion azimuthal anisotropies for p(T)>1.2 GeV/c exceed the elliptic flow values by about 60% in midcentral collisions. These nonflow contributions are attributed to nearside and back-to-back jetlike correlations, the latter exhibiting centrality dependent broadening.
The clonal relationships among 261 erythromycin-resistant Streptococcus pyogenes isolates collected in 1986-1997 from nine countries in Europe and North and South America were studied by using two molecular typing methods: Vir typing and random amplified polymorphic DNA (RAPD) analysis. A total of 49 different Vir genotypes (VTs) and 33 different RAPD patterns were noted among the 261 isolates. Isolates that shared the same VT and RAPD pattern were considered to belong to the same clone. Although as many as 60 different clones were found among the isolates studied, only seven clones, comprising 157 of the 261 (60%) isolates, were found in more than one country. Five of these seven clones expressed the M phenotype known to be associated with the drug efflux mechanism, and only two clones expressed the macrolide-lincosamide-streptogramin B-resistance phenotype. The results indicate a polyclonal spread of erythromycin-resistant Streptococcus pyogenes. Furthermore, predominance of the seven clones indicates that erythromycin-resistant Streptococcus pyogenes of the same clonal origin may be widely distributed and found in several different countries.
Explore the source record for details and available documents.
The prevalence of isolates of Streptococcus pneumoniae (pneumococcus) that are resistant to antimicrobial agents is increasing globally. We studied the connection between antimicrobial resistance of pneumococci and regional use of antimicrobial agents in Finland. In 1997, a total of 6106 pneumococcal isolates were identified in clinical microbiology laboratories in Finland. Most of the pneumococci were isolated from respiratory tract samples, 8% were from blood culture samples, and 0.5% were from cerebrospinal fluid samples. The regional levels of resistance for pneumococci in 1997 were compared with the regional rates of use of antimicrobial agents from 1995 through 1996. We found that resistance to macrolides correlated highly significantly with macrolide use (P=.006). A significant correlation was also found between resistance to trimethoprim-sulfamethoxazole and trimethoprim-sulfamethoxazole use (P=.043). We did not find a correlation between penicillin resistance and the use of any antimicrobial agent. The positive correlation between macrolide-resistant pneumococci and the use of macrolides is worrying, because macrolides are used worldwide in the treatment of patients with respiratory tract infections, which are often caused by pneumococci.
Sulfonamides have a glorious history. In 1935, they were the first class of true antimicrobial agents with life-saving potency. Today, 66 years later, increased bacterial resistance to sulfonamides and to trimethoprim (TMP), a synthetic antimicrobial agent that is 30 years younger than sulfonamides, has limited their use to only a few indications. In the treatment and prophylaxis of patients with urinary tract infections, trimethoprim-sulfamethoxazole (TMP-SMZ) or TMP alone is still considered the first-line drug of choice, although increased bacterial resistance to these agents has been linked with treatment failure. TMP-SMZ has a possible role as a second- or third-line treatment for patients who have respiratory tract infections. In the developing world, where this inexpensive drug is widely used as first-line treatment, bacterial resistance has caused problems, especially with regard to the treatment of patients with severe respiratory tract infections. Use of TMP-SMZ as prophylaxis for Pneumocystis carinii infection has rapidly increased the multidrug resistance of bacterial pathogens found in human immunodeficiency virus-infected patients. Today, detailed and reliable knowledge on the resistance of bacterial pathogens to both TMP-SMZ and TMP is an essential requirement for the safe and effective use of these drugs in all clinical settings.
In bacteria associated with humans, antimicrobial resistance is common, both in clinical isolates and in the less-studied commensal flora, and it is thought that commensal and environmental bacteria might be a hidden reservoir of resistance. Gilliver et al. have reported that resistance is also prevalent in faecal bacteria from wild rodents living in northwest England. Here we test the faeces of moose, deer and vole in Finland and find an almost complete absence of resistance in enterobacteria. Resistance is thus not a universal property of enterobacterial populations, but may be a result of the human use of antibiotics.
The aim of this study was to survey current treatment practices for common infections in primary care as a basis for implementation of recently released evidence-based guidelines for community-acquired infections. A point-prevalence survey was conducted in 30 health centres in the Finnish primary care system with a population base of 819,777. All patients consulting the health centres for an infection during a 1-week period were included in the study. The main outcome measures were the prevalence of antibiotic prescription and the selection of drugs by infection diagnosis. Of the 7777 recorded consultations, 85% were with a physician and the rest with a nurse. The most common cause for a visit was respiratory tract infections (74%), followed by skin/wound infections and urinary tract infections (both 6%). The infection panorama varied markedly according to age: in the youngest children (< 5 y) 84% of the infections were respiratory tract infections whereas the corresponding figure for patients > 65 y was 50%; the proportions of visits for urinary tract infections in these age groups were 7% and 26%, respectively. Of the patients with acute bronchitis, 70% were treated with antimicrobial agents, mostly macrolides (39%) and doxycycline (36%). Of the otitis media patients, 53% were treated with amoxicillin, 16% with macrolides and 16% with sulphatrimethoprim. Macrolides were mostly used to treat otitis media (31%), acute bronchitis (26%) and sinusitis (20%). In conclusion, antimicrobial agents are still used excessively in Finland, particularly for the treatment of acute bronchitis. Moreover, the selection of drugs for treating sinusitis and otitis media is non-optimal; macrolides and cephalosporins are frequently chosen unnecessarily. Knowledge of the indication-based prescription practices for antimicrobial agents is essential in order to improve the treatment habits of primary care physicians. The data obtained in this study provide a unique tool for the active and targeted implementation of evidence-based guidelines for primary care physicians.
A patient with severe burns who was colonized by multiresistant Acinetobacter baumannii was cared for in contact isolation by staff intensively trained on hospital hygiene. Of the 1,907 postexposure cultures from the staff and 425 environmental samples, only 0.7% and 4%, respectively, yielded this microorganism. These data show that strict hygienic measures may limit staff colonization and contamination of the environment byA baumannii.
The in vitro susceptibilities of 184 erythromycin-resistant streptococci to a novel ketolide, telithromycin (HMR 3647), were tested. These clinical isolates included 111 Streptococcus pyogenes, 18 group C streptococcus, 18 group G streptococcus, and 37 Streptococcus pneumoniae strains. The MICs for all but eight S. pyogenes strains were < or =0.5 microg/ml, indicating that telithromycin is active in vitro against erythromycin-resistant Streptococcus strains. All strains for which MICs were > or =1 microg/ml had an erm(B) resistance gene and six strains for which MICs were > or =4 microg/ml had a constitutive erm(B) gene (MIC range, 4 to 64 microg/ml). Interestingly, for S. pneumoniae strains with a constitutive erm(B) gene, MICs were < or =0.25 microg/ml (MIC range, < or =0.008 to 0.25 microg/ml). Our in vitro data show that for S. pyogenes strains which constitutively express the erm(B) methylase gene, MICs are so high that the strains might be clinically resistant to telithromycin.
The replica plating method was evaluated for detection of the antimicrobial resistance of normal bacterial flora of the skin and was compared with the results of a ten-colony method. If > or = 10% of the colonies from the master plate grew on a plate containing an antibiotic, the sensitivity of replica plating was comparable to that of a ten-colony method for samples containing resistant bacteria. However, this method classified significantly more samples as resistant to all eight antibiotics tested if the detection breakpoint was lowered to > or = 1% of the original colonies. Replica plating is an effective and practical tool for screening skin flora for resistance, also in samples with a low proportion of resistant strains.
A total of 238 erythromycin-resistant Streptococcus pyogenes isolates were collected in 1986-1997 from eight different countries in Europe and North and South America. The antibiotic susceptibility patterns of all isolates and the resistance genes of 92 isolates of known clonal origin were studied. The mefA gene was detected in all 54 isolates with the M-phenotype and was found in every country. The ermTR and the ermB genes were detected in 27 and 11, respectively, of the 38 isolates with the macrolide-lincosamide-streptogramin B resistance phenotypes. In addition to the mefA gene, the recently sequenced ermTR gene was also widely distributed among isolates of different clonal origin.
Resistance to cefuroxime, penicillin, tetracycline, and mercury is reported for 839 Streptococcus mutans isolates from 209 human study subjects. The MICs of these drugs did not differ for isolates from one dental amalgam group and two nonamalgam subsets: a group with no known exposure to amalgam and a group whose members had their amalgam fillings removed.
Enterobacteria in fecal flora are often reported to be highly resistant. Escherichia coli is the main species; resistance data on other species are rare. To assess the effect of the host's environment, antimicrobial resistance was determined in fecal species of the family Enterobacteriaceae from three populations: healthy people (HP)(n = 125) with no exposure to antimicrobials for 3 months preceding sampling, university hospital patients (UP) (n = 159) from wards where the antibiotic use was 112 defined daily doses (DDD)/bed/month, and geriatric long-term patients (LTP) (n = 74) who used 1.8 DDD/bed/month. The mean length of hospital stay was 5 days for the UP and 22 months for the LTP. The isolates were identified to at least genus level, and MICs of 16 antimicrobials were determined. From the university hospital, resistance data on clinical Enterobacteriaceae isolates were also collected. Resistance data for on average two different isolates per sample (range, 1 to 5) were analyzed: 471 E. coli isolates and 261 other Enterobacteriaceae spp. Resistance was mainly found among E. coli; even in HP, 18% of E. coli isolates were resistant to two or more antimicrobial groups, with MIC patterns indicative of transferable resistance. Other fecal enterobacteria were generally susceptible, with little typically transferable multiresistance. Clinical Klebsiella and Enterobacter isolates were significantly more resistant than fecal isolates. The resistance patterns at both hospitals mirrored the patterns of antibiotic use, but LTP E. coli isolates were significantly more resistant than those from UP. Conditions permitting an efficient spread may have been more important in sustaining high resistance levels in the LTP. E. coli was the main carrier of antimicrobial resistance in fecal flora; resistance in other species was rare in the absence of antimicrobial selection.
The Finnish Study Group for Antimicrobial Resistance (FiRe), a network founded in 1991, has established a standard routine susceptibility testing method that yields reliable and comparable results for both diagnostic and epidemiological purposes. Results