Haemophilus influenzae is a major pathogen, and beta-lactams are first-line drugs. Resistance due... more Haemophilus influenzae is a major pathogen, and beta-lactams are first-line drugs. Resistance due to altered penicillin-binding protein 3 (rPBP3) is frequent, and susceptibility testing of such strains is challenging. A collection of 154 beta-lactamase-negative isolates with a large proportion of rPBP3 (67.5%) was used to evaluate and compare Etest (Haemophilus test medium [HTM]) and disk diffusion (EUCAST method) for categorization of susceptibility to aminopenicillins and cefuroxime, using MICs generated with broth (HTM) microdilution and clinical breakpoints from CLSI and EUCAST as the gold standards. In addition, the proficiency of nine disks in screening for the rPBP3 genotype (N526K positive) was evaluated. By Etest, both essential and categorical agreement were generally poor (<70%), with high very major errors (VME) (CLSI, 13.0%; EUCAST, 34.3%) and falsely susceptible rates (FSR) (CLSI, 87.0%; EUCAST, 88.3%) for ampicillin. Ampicillin (2 μg) with adjusted (+2 mm) zone breakpoints was superior to Etest for categorization of susceptibility to ampicillin (agreement, 74.0%; VME, 11.0%; FSR, 28.3%). Conversely, Etest was superior to 30 μg cefuroxime for categorization of susceptibility to cefuroxime (agreement, 57.1% versus 60.4%; VME, 2.6% versus 9.7%; FSR, 7.1% versus 26.8%). Benzylpenicillin (1 unit) (EUCAST screening disk) and cefuroxime (5 μg) identified rPBP3 isolates with highest accuracies (95.5% and 92.2%, respectively). In conclusion, disk screening reliably detects rPBP3 H. influenzae, but false ampicillin susceptibility is frequent with routine methods. We suggest adding a comment recommending high-dose aminopenicillin therapy or the use of other agents for severe infections with screening-positive isolates that are susceptible to aminopenicillins by gradient or disk diffusion.
Rat bite fever and Haverhill fever are caused by Streptobacillus moniliformis which is part of th... more Rat bite fever and Haverhill fever are caused by Streptobacillus moniliformis which is part of the natural oral flora of rats and other rodents. Fever accompanied by headache, nausea and myalgia develops within ten days. Complications can be fatal. A case of rat bite fever is described. A 48-year-old woman developed fever and malaise five days after being bitten by a pet rat. Two days later rash and arthritis in the hand and feet developed. Erythromycin was administered without effect. Ten days after the bite the patient was admitted to hospital and recovered after two weeks of intravenous penicillin therapy. S moniliformis was isolated from blood culture. On admission CRP was 231, ESR 88, ASAT 87, ALAT 218 and gamma-GT 461. Laboratory results normalized after therapy. In cases of fever after rodent bites, S moniliformis infection should always be considered. Diagnosis is made by blood culture or cultivation from pus from the bite wound. First choice therapy is penicillin, or in cas...
During a study on the epidemiology of Staphylococcus aureus colonization in newborns, mothers, an... more During a study on the epidemiology of Staphylococcus aureus colonization in newborns, mothers, and hospital staff, S. aureus was isolated from 536 of 1,945 specimens. Ninety-three isolates of S. aureus from the three groups of individuals were included in a study to evaluate the potential of DNA fingerprinting for strain differentiation. The 93 isolates were also phage typed and their plasmid profiles were analyzed. Cleavage of DNA with BamHI resulted in 13 different DNA restriction endonuclease band patterns (DNA REBPs), one of which consisted of eight isolates whose DNA was not cleaved with BamHI. The DNAs from these eight isolates were easily cleaved with HindIII. The different DNA REBPs were stable both during in vitro and in vivo growth and allowed strain differentiation within phage groups or types. We could not show any strong association between DNA REBP classes, phage types or groups, and plasmid profiles. Of the 93 isolates, 27 (29.0%) could not be phage typed and 12 (12.9...
In Norway, data on the etiology of community-acquired pneumonia (CAP) in hospitalized patients ar... more In Norway, data on the etiology of community-acquired pneumonia (CAP) in hospitalized patients are limited. The aims of this study were to investigate the bacterial etiology of CAP in hospitalized patients in Norway, risk factors for CAP, and possible differences in risk factors between patients with Legionnaire's disease and pneumonia due to other causes. Adult patients with radiologically confirmed CAP admitted to hospital were eligible for the study. Routine aerobic and Legionella culture of sputum, blood culture, urinary antigen test for Legionella pneumophila and Streptococcus pneumoniae, polymerase chain reaction detection of Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Bordetella pertussis from throat specimens, and serology for L. pneumophila serogroup 1-6 were performed. A questionnaire, which included demographic and clinical data, risk factors, and treatment, was completed. We included 374 patients through a 20-month study period in 2007-2008. The etiological ...
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 20, 2002
Bacteriological investigation of urine often shows the presence of alpha-haemolytic streptococci,... more Bacteriological investigation of urine often shows the presence of alpha-haemolytic streptococci, but the clinical significance of this finding may be unclear. Among the alpha-haemolytic streptococci found in urine is Aerococcus urinae, which is pathogenic. We present a prospective study of the prevalence and antibiotic susceptibility of A urinae in urine samples sent to a microbiology laboratory in Norway. Seven out of 27 alpha-haemolytic streptococcal isolates were A urinae. This represents 0.3% of all urine isolates from our laboratory. Appropriate methods for identification and resistance determination are described. Microbiological laboratories should include identification of A urinae in their diagnostic repertoire. Recommended treatment against A urinae is ampicillin or nitrofurantoin.
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 10, 2001
The bacterium that causes human granulocytic ehrlichiosis may be transmitted by ticks. We describ... more The bacterium that causes human granulocytic ehrlichiosis may be transmitted by ticks. We describe two patients with human granulocytic ehrlichiosis. During the summer of 1998, both patients were bitten by ticks. Four to 7 days later they developed influenza-like symptoms with fever, headache and myalgia. After 4 and 21 days, respectively, both patients were given doxycycline for suspected bacterial respiratory diseases, and recovered. Blood samples for human granulocytic ehrlichiosis antibodies showed a fourfold increase in titer in one patient and a remaining high titer in the other. Both patients had a positive polymerase chain reaction with primers specific for the Ehrlichia phagocytophilae genogroup. The two patients fulfill the human granulocytic ehrlichiosis diagnostic criteria set by Centers for Disease Controls and Prevention, and are the first two human granulocytic ehrlichiosis cases described in Norway.
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 10, 1989
During the period from January 1987 to June 1988 DNA fingerprinting was used to identify carriers... more During the period from January 1987 to June 1988 DNA fingerprinting was used to identify carriers of the disease-causing strain of Neisseria meningitidis among the patients contacts. A total of 432 persons were screened during nine episodes. The overall carrier-rate was 16.2%, and the causative strain was found in 3.4% of the contacts. Eleven carriers were successfully treated with rifampicin, whereas two of three carriers treated with penicillin remained carriers. We conclude that DNA fingerprinting is a valuable tool for rapid identification of carriers of the causative organism in order to eradicate the epidemic strain of N. meningitidis.
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 20, 2001
Nosocomial infections caused by methicillin-resistant Staphylococcus aureus (MRSA) represent an i... more Nosocomial infections caused by methicillin-resistant Staphylococcus aureus (MRSA) represent an increasing problem worldwide. We report two outbreaks of methicillin-resistant S. aureus at Haukeland University Hospital during 1998-99. During the fall of 1998, four patients in the dermatological ward and three of their relatives were infected or colonised with MRSA. The strain was probably introduced by an eczematous patient who had recently arrived from Japan. Three patients became chronic carriers. The second outbreak involved three other hospital departments in July-August 1999. The index patient, a multitraumatised japanese tourist, died 16 days after admission. Two other patients were infected, one of them became a chronic carrier. According to official guidelines, neither of the index patients needed MRSA screening. Pulsed field gel-electrophoresis of the MRSA isolates revealed two different strains at the first outbreak, both probably introduced from the index patient, and one ...
Forty-three strains of adenovirus type 3 isolated from patients in Norway between 1970 and 1991 w... more Forty-three strains of adenovirus type 3 isolated from patients in Norway between 1970 and 1991 were analyzed with four restriction endonucleases. Bg1 II was the most discriminative enzyme. Five genotypes were identified and one of these has not been described before (Ad3a12). During both the epidemics in this period, new genotypes were introduced into the population. The same genotypes were identified in Norway as have previously been found in the northern parts of Europe, America and the Soviet Union.
... BJBRN-ERIK KRISTIANSEN', YNGVAR TVETEN', EIRIK ASK', TOR REITEN&am... more ... BJBRN-ERIK KRISTIANSEN', YNGVAR TVETEN', EIRIK ASK', TOR REITEN', ARNE-BIRGER KNAPSKOG3, JON STEEN-JOHNSEN4 and GUNNAR HOPEN ... Weihe P, Mathiassen B, Rasmussen JM, Petersen T, Isager H. An epidemic outbreak of group B meningococcal disease ...
Haemophilus influenzae is a major pathogen, and beta-lactams are first-line drugs. Resistance due... more Haemophilus influenzae is a major pathogen, and beta-lactams are first-line drugs. Resistance due to altered penicillin-binding protein 3 (rPBP3) is frequent, and susceptibility testing of such strains is challenging. A collection of 154 beta-lactamase-negative isolates with a large proportion of rPBP3 (67.5%) was used to evaluate and compare Etest (Haemophilus test medium [HTM]) and disk diffusion (EUCAST method) for categorization of susceptibility to aminopenicillins and cefuroxime, using MICs generated with broth (HTM) microdilution and clinical breakpoints from CLSI and EUCAST as the gold standards. In addition, the proficiency of nine disks in screening for the rPBP3 genotype (N526K positive) was evaluated. By Etest, both essential and categorical agreement were generally poor (<70%), with high very major errors (VME) (CLSI, 13.0%; EUCAST, 34.3%) and falsely susceptible rates (FSR) (CLSI, 87.0%; EUCAST, 88.3%) for ampicillin. Ampicillin (2 μg) with adjusted (+2 mm) zone breakpoints was superior to Etest for categorization of susceptibility to ampicillin (agreement, 74.0%; VME, 11.0%; FSR, 28.3%). Conversely, Etest was superior to 30 μg cefuroxime for categorization of susceptibility to cefuroxime (agreement, 57.1% versus 60.4%; VME, 2.6% versus 9.7%; FSR, 7.1% versus 26.8%). Benzylpenicillin (1 unit) (EUCAST screening disk) and cefuroxime (5 μg) identified rPBP3 isolates with highest accuracies (95.5% and 92.2%, respectively). In conclusion, disk screening reliably detects rPBP3 H. influenzae, but false ampicillin susceptibility is frequent with routine methods. We suggest adding a comment recommending high-dose aminopenicillin therapy or the use of other agents for severe infections with screening-positive isolates that are susceptible to aminopenicillins by gradient or disk diffusion.
Rat bite fever and Haverhill fever are caused by Streptobacillus moniliformis which is part of th... more Rat bite fever and Haverhill fever are caused by Streptobacillus moniliformis which is part of the natural oral flora of rats and other rodents. Fever accompanied by headache, nausea and myalgia develops within ten days. Complications can be fatal. A case of rat bite fever is described. A 48-year-old woman developed fever and malaise five days after being bitten by a pet rat. Two days later rash and arthritis in the hand and feet developed. Erythromycin was administered without effect. Ten days after the bite the patient was admitted to hospital and recovered after two weeks of intravenous penicillin therapy. S moniliformis was isolated from blood culture. On admission CRP was 231, ESR 88, ASAT 87, ALAT 218 and gamma-GT 461. Laboratory results normalized after therapy. In cases of fever after rodent bites, S moniliformis infection should always be considered. Diagnosis is made by blood culture or cultivation from pus from the bite wound. First choice therapy is penicillin, or in cas...
During a study on the epidemiology of Staphylococcus aureus colonization in newborns, mothers, an... more During a study on the epidemiology of Staphylococcus aureus colonization in newborns, mothers, and hospital staff, S. aureus was isolated from 536 of 1,945 specimens. Ninety-three isolates of S. aureus from the three groups of individuals were included in a study to evaluate the potential of DNA fingerprinting for strain differentiation. The 93 isolates were also phage typed and their plasmid profiles were analyzed. Cleavage of DNA with BamHI resulted in 13 different DNA restriction endonuclease band patterns (DNA REBPs), one of which consisted of eight isolates whose DNA was not cleaved with BamHI. The DNAs from these eight isolates were easily cleaved with HindIII. The different DNA REBPs were stable both during in vitro and in vivo growth and allowed strain differentiation within phage groups or types. We could not show any strong association between DNA REBP classes, phage types or groups, and plasmid profiles. Of the 93 isolates, 27 (29.0%) could not be phage typed and 12 (12.9...
In Norway, data on the etiology of community-acquired pneumonia (CAP) in hospitalized patients ar... more In Norway, data on the etiology of community-acquired pneumonia (CAP) in hospitalized patients are limited. The aims of this study were to investigate the bacterial etiology of CAP in hospitalized patients in Norway, risk factors for CAP, and possible differences in risk factors between patients with Legionnaire's disease and pneumonia due to other causes. Adult patients with radiologically confirmed CAP admitted to hospital were eligible for the study. Routine aerobic and Legionella culture of sputum, blood culture, urinary antigen test for Legionella pneumophila and Streptococcus pneumoniae, polymerase chain reaction detection of Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Bordetella pertussis from throat specimens, and serology for L. pneumophila serogroup 1-6 were performed. A questionnaire, which included demographic and clinical data, risk factors, and treatment, was completed. We included 374 patients through a 20-month study period in 2007-2008. The etiological ...
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 20, 2002
Bacteriological investigation of urine often shows the presence of alpha-haemolytic streptococci,... more Bacteriological investigation of urine often shows the presence of alpha-haemolytic streptococci, but the clinical significance of this finding may be unclear. Among the alpha-haemolytic streptococci found in urine is Aerococcus urinae, which is pathogenic. We present a prospective study of the prevalence and antibiotic susceptibility of A urinae in urine samples sent to a microbiology laboratory in Norway. Seven out of 27 alpha-haemolytic streptococcal isolates were A urinae. This represents 0.3% of all urine isolates from our laboratory. Appropriate methods for identification and resistance determination are described. Microbiological laboratories should include identification of A urinae in their diagnostic repertoire. Recommended treatment against A urinae is ampicillin or nitrofurantoin.
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 10, 2001
The bacterium that causes human granulocytic ehrlichiosis may be transmitted by ticks. We describ... more The bacterium that causes human granulocytic ehrlichiosis may be transmitted by ticks. We describe two patients with human granulocytic ehrlichiosis. During the summer of 1998, both patients were bitten by ticks. Four to 7 days later they developed influenza-like symptoms with fever, headache and myalgia. After 4 and 21 days, respectively, both patients were given doxycycline for suspected bacterial respiratory diseases, and recovered. Blood samples for human granulocytic ehrlichiosis antibodies showed a fourfold increase in titer in one patient and a remaining high titer in the other. Both patients had a positive polymerase chain reaction with primers specific for the Ehrlichia phagocytophilae genogroup. The two patients fulfill the human granulocytic ehrlichiosis diagnostic criteria set by Centers for Disease Controls and Prevention, and are the first two human granulocytic ehrlichiosis cases described in Norway.
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 10, 1989
During the period from January 1987 to June 1988 DNA fingerprinting was used to identify carriers... more During the period from January 1987 to June 1988 DNA fingerprinting was used to identify carriers of the disease-causing strain of Neisseria meningitidis among the patients contacts. A total of 432 persons were screened during nine episodes. The overall carrier-rate was 16.2%, and the causative strain was found in 3.4% of the contacts. Eleven carriers were successfully treated with rifampicin, whereas two of three carriers treated with penicillin remained carriers. We conclude that DNA fingerprinting is a valuable tool for rapid identification of carriers of the causative organism in order to eradicate the epidemic strain of N. meningitidis.
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 20, 2001
Nosocomial infections caused by methicillin-resistant Staphylococcus aureus (MRSA) represent an i... more Nosocomial infections caused by methicillin-resistant Staphylococcus aureus (MRSA) represent an increasing problem worldwide. We report two outbreaks of methicillin-resistant S. aureus at Haukeland University Hospital during 1998-99. During the fall of 1998, four patients in the dermatological ward and three of their relatives were infected or colonised with MRSA. The strain was probably introduced by an eczematous patient who had recently arrived from Japan. Three patients became chronic carriers. The second outbreak involved three other hospital departments in July-August 1999. The index patient, a multitraumatised japanese tourist, died 16 days after admission. Two other patients were infected, one of them became a chronic carrier. According to official guidelines, neither of the index patients needed MRSA screening. Pulsed field gel-electrophoresis of the MRSA isolates revealed two different strains at the first outbreak, both probably introduced from the index patient, and one ...
Forty-three strains of adenovirus type 3 isolated from patients in Norway between 1970 and 1991 w... more Forty-three strains of adenovirus type 3 isolated from patients in Norway between 1970 and 1991 were analyzed with four restriction endonucleases. Bg1 II was the most discriminative enzyme. Five genotypes were identified and one of these has not been described before (Ad3a12). During both the epidemics in this period, new genotypes were introduced into the population. The same genotypes were identified in Norway as have previously been found in the northern parts of Europe, America and the Soviet Union.
... BJBRN-ERIK KRISTIANSEN', YNGVAR TVETEN', EIRIK ASK', TOR REITEN&am... more ... BJBRN-ERIK KRISTIANSEN', YNGVAR TVETEN', EIRIK ASK', TOR REITEN', ARNE-BIRGER KNAPSKOG3, JON STEEN-JOHNSEN4 and GUNNAR HOPEN ... Weihe P, Mathiassen B, Rasmussen JM, Petersen T, Isager H. An epidemic outbreak of group B meningococcal disease ...
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