Sigurdur Gudmundsson

Sigurdur Gudmundsson
University of Iceland | HI · Faculty of Medicine

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90
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Introduction
Skills and Expertise

Publications

Publications (90)
Article
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Objectives Nationwide study on the epidemiology, clinical characteristics and outcomes among patients with native joint infection (NJI) in Iceland, 2003–2017. Methods All positive synovial fluid culture results in Iceland were identified and medical records reviewed. Results A total of 299 NJI (40 children and 259 adults) were diagnosed in Icelan...
Article
Aims: Surveillance of geographical variations in cardiovascular health is important in order to achieve the objectives of reducing regional health disparities. We aimed to explore differences in cardiovascular disease (CVD) mortality and prevalence of CVD diagnoses made in primary and in-patient care, as well as risk factor distribution by geograp...
Article
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Introduction: Malaria is one of the most common causes of preventable deaths in the developing countries, especially among children. A previous study of imported malaria in Iceland during 1980-1997 identified 15 confirmed cases. The objective of this retrospective study was to update epidemiological data on malaria in Iceland, 1998-2014. Material...
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We report a case of prosthetic valve nocardia endocarditis. A 43 year old farmer underwent aortic valve replacement with a bioprosthetic valve. The immediate post-operative course was uneventful but 2 weeks later he developed fever. A trans-oesophageal echocardiogram (TEE) showed a string like structure attached to the prosthetic valve. Blood cultu...
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Introduction: Iceland is well suited for epidemiological research due to well-kept patient records, easy followup of patients and nationwide health care databases. This study provides a nationwide 30-year epidemiological overview of the HIV epidemic in the country.
Article
Objective To describe pregnancy complications, mode of delivery and neonatal outcomes by mother's residence.DesignRegister-based cohort study.SettingGeographical regions of Iceland.PopulationLive singleton births from January 1 2000 to December 31 2009 (n=40 982) and stillbirths ≥22 weeks or weighing ≥500 g (n=145).Methods Logistic regression was u...
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Herpes simplex encephalitis (HSE) is a serious disease with 10-20% mortality and high rate of neuropsychiatric sequelae. This study is a long-term, nationwide study in a single country, Iceland. Clinical data were obtained from patient records and from DNA PCR and antibody assays of CSF. Diagnosis of HSE was classified as definite, possible or reje...
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Introduction: Bacterial meningitis is a serious disease with a mortality rate of 15-20% in adults. We conducted a population-based study of bacterial meningitis in adults (≥ 16 y) in Iceland, 1995-2010. Methods: Cases were identified based on positive bacterial cultures from cerebrospinal fluid (CSF) and/or the ICD codes for bacterial meningitis...
Article
Aims: The aim of this study was to explore differences in self-rated health and physician-diagnosed disease across geographical regions in Iceland to better understand regional requirements for health services. Methods: Data on self-rated health and diagnosed disease from a 2007 national health survey (n=5909; response rate 60.3%) across geograp...
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The study aimed to determine whether exposure to a volcanic eruption was associated with increased prevalence of physical and/or mental symptoms. Cohort, with non-exposed control group. Natural disasters like volcanic eruptions constitute a major public-health threat. The Icelandic volcano Eyjafjallajökull exposed residents in southern Iceland to c...
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To study potential changes in attendance at emergency departments (ED) in Reykjavík immediately following the swift economic meltdown in Iceland in October 2008. Using electronic medical records of the National University Hospital in Reykjavík, a population-based register study was conducted contrasting weekly attendance rates at Reykjavík ED (card...
Article
Objectives: To determine the incidence of herpes zoster (HZ) and frequency of complications, mainly the incidence of postherpetic neuralgia (PHN). Design: Prospective follow-up study. Setting: Primary health care in Iceland. Main outcome measures: Incidence of HZ, age and sex distribution of patients and discomfort or pain 1, 3 and 12 months after...
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Nosocomial infections are common in intensive care units (ICU). The objectives of this study were to determine risk factors of ICU-acquired infections, and potential mortality attributable to such infections. An observational study was performed in a 10-bed multidisciplinary ICU. For a period of 27 months, all patients admitted for >or=48 h were in...
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The relative effects of risk factors on the prevalence of resistant pneumococcal clones are hard to determine. Our aim was to evaluate the effect of risk factors on the prevalence of resistant pneumococci in Iceland in 2003 and compare these data with results of identical studies performed in 1993 and 1998. A randomized sample of 1,107 children was...
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Hægt er að lesa greinina í heild sinni með því að smella á hlekkinn View/Open Á undanförnum áratugum hafa langvinnir sjúkdómar orðið umfangsmesta verkefni heilbrigðisþjónustu Vesturlanda. Framþróun í læknavísindum hefur leitt til bættrar meðferðar sem veldur því að fólk með langvinna sjúkdóma lifir lengur. Þessum sjúkdómum fylgja þó oft erfið veiki...
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To investigate potential links between antimicrobial drug use for acute otitis media (AOM) and tympanostomy tube placements, and the relationship between parental views and physician antimicrobial prescribing habits. Cross-sectional community study repeated after five years. Representative samples of children aged 1-6 years in four well-defined com...
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Dietary fish oil is believed to have a beneficial effect in various infections and in autoimmune disorders. This effect may correspond to an altered immune response. In order to discover whether the effect of dietary fish oil is different in various infections, we studied the survival of mice fed fish oil or corn oil supplemented diets and infected...
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Pharmacokinetic (PK) and pharmacodynamic (PD) properties for the selection of resistant pneumococci were studied by using three strains of the same serotype (6B) for mixed-culture infection in time-kill experiments in vitro and in three different animal models, the mouse peritonitis, the mouse thigh, and the rabbit tissue cage models. Treatment reg...
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Widespread antimicrobial use is a risk factor for development of antimicrobial resistance. Antimicrobial treatment of acute otitis media (AOM) may not always be necessary. Little is known about the influence of parental expectations on physicians' decision-making in relation to treatment of AOM. Evidence is insufficient as to whether tympanostomy t...
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The effects of community-wide interventions to reduce resistance rates are poorly understood. This study evaluated the effect of reduced antimicrobial usage on the spread of penicillin-nonsusceptible pneumococci (PNSP) in four communities in Iceland. The study was performed after interventions to reduce antimicrobial usage and compared to an identi...
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Objective: The size of waiting lists has traditionally been viewed as a fairly good measure of the quality of health care services. No statistical analysis exists in Iceland of the length of waiting times and the potential variation between groups of patients. This study was conducted within the office of the Directorate of Health in Iceland. This...
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Objective: Fish-oil enriched diet has a protective effect on experimental animals infected intramuscularly with Klebsiella pneumoniae. It also has beneficial effect in several other diseases, including autoimmune disorders. The pathophysiological effects of dietary fish-oil have still not been revealed although it is expected to influence the immu...
Article
Objective: Dietary fish-oil has beneficial effect in infections and in autoimmune disorders. This effect is thought to be associated with alterations in the immune system. The Gram negative organism Klebsiella pneumoniae has been used as an infective agent in most studies investigating the effect of dietary fish-oil on infection. The immune respon...
Article
Objective: Epidemiological studies have indicated that high intake of w-3 fatty acids influence various diseases such as cardiovascular diseases and autoimmune disorders. These fatty acids are essential in the diet since the body can not form them de novo. Fish oil is rich in w-3 fatty acids but the w-3 content of vegetable oil is low. The researc...
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Clinical and animal studies indicate that with optimal dosing, penicillin may still be effective against penicillin-nonsusceptible pneumococci (PNSP). The present study examined whether the same strains of penicillin-susceptible pneumococci (PSP) and PNSP differed in their pharmacodynamic responses to penicillin by using comparable penicillin dosin...
Article
To estimate the frequency, duration, and clinical importance of postherpetic neuralgia after a single episode of herpes zoster. Prospective cohort study with long term follow up. Primary health care in Iceland. 421 patients with a single episode of herpes zoster. Age and sex distribution of patients with herpes zoster, point prevalence of postherpe...
Article
To follow the clinical course of herpes zoster and to determine the incidence, frequency of complications and association with malignancy in children and adolescents. Prospective cohort study in a primary health care setting in Iceland. The main outcome measures were age and sex distribution of patients and discomfort or pain 1, 3 and 12 months aft...
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Full-text available
Changes in bacterial ultrastructure after antibiotic exposure and during the postantibiotic effect (PAE) have been demonstrated by electron microscopy (EM). However, EM is qualitative and subject to individual interpretation. In contrast, flow cytometry gives qualitative and quantitative information. The sizes and nucleic acid contents of Escherich...
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Objective: First to measure plasma HIV-1 RNA in Icelandic HIV infected individuals and second to evaluate the initial effects of new combination regimens on viral load and CD4+ cell counts in HIV infected patients in Iceland. Material and methods: The cohort studied consis notted of all HIV infected individuals we received samples from during th...
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Objective: To describe the application of and analyze the cost effects of antibiotic utilization review at Landspitalinn, the National University Hospital in Iceland, and review the use of prophylactic antibiotics in a general surgical ward. Material and methods: The study was undertaken during a two month period in 1996. Patients in wards 11-A...
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Orbital implant infection is a rare cause of anophthalmic socket pain. Because of the potential danger of infection spreading to nearby structures, it is of paramount importance to diagnose the condition as soon as possible. Scintigraphy is a method for diagnosis of graft infections by radioisotopic imaging of inflammatory sites. We report on a pat...
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Objective: To study the postantibiotic effect (PAE) for Bacteroides fragilis after exposure to common anaerobic antimicrobials with two different methods, by viable counting and by measuring CO2 generation in a BACTEC® blood culture system. Method: Four strains of B. fragilis were exposed for 1,2 and 4 h to cefoxitin, chloramphenicol, clindamycin,...
Article
Most clinical overviews of acute bacterial meningitis have either focused on children or all age groups combined, although the disease poses serious problems in the adult population. To study the clinical and microbiological features of adult bacterial meningitis in Iceland, as a representative of the average European or North American community. D...
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Postantibiotic effects (PAE) and control-related effective regrowth time (CERT) of dicloxacillin, vancomycin, rifampin and gentamicin in Staphylococcus aureus and imipenem, gentamicin, tobramycin, doxycycline and rifampin in Escherichia coli were measured by standard viability counting and [3H]thymidine incorporation. For PAE determination, the two...
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To study the correlation of antimicrobial consumption with the carriage rate of penicillin resistant and multiresistant pneumococci in children. Cross sectional and analytical prevalence study. Five different communities in Iceland. Prevalence of nasopharyngeal carriage of penicillin resistant pneumococci in children aged under 7 years in relation...
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Objective. To describe the epidemiology of AIDS and HIV infection in Iceland with demographic characteristics and associated risk factors. Design. Survey of national data reported to the Office of the Director General of Public Health in Iceland from November 1985 to December 311994. The dates of diagnosis of HIV infection, AIDS and death due to AI...
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Introduction: Antibiotics are responsible for 20-25% of the total drug-cost in the larger hospitals in Iceland. Studies from other countries, both in Europe and North-America suggest that 40-70% of both antibiotic therapy and prophylaxis is inappropriate in the larger teaching hospitals. We undertook a prospective study to determine the patterns o...
Article
Objective: To determine the nosocomial infection rate, pathogens, colonisation and hospital mortality in the Intensive Care Unit (ICU) at Landspitalinn, which is a ten bed, general medical-surgical ICU. Methods: Patients admitted for more than 48 hours were included. Surveillance- cultures were performed on admission and thereafter three times a...
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Introduction: Although acute bacterial meningitis is most common among children, the disease nevertheless poses serious problems in the adult population. However, most clinical overviews of the disease have either focused on children or all age groups combined. Subjects and methods: Information on all patients 5=16 years of age diagnosed in Icel...
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Studies on bacterial metabolism during the postantibiotic effect (PAE) period are limited but might provide insight into the nature of the PAE. We evaluated the rate of DNA synthesis in bacteria during the PAE period after a 1-h exposure of organisms in the logarithmic growth phase to various antibiotics. Staphylococcus aureus ATCC 25923 was expose...
Article
Varying temperatures (35.5 degrees C, 38.5 degrees C, 41 degrees C) only minimally affected growth rates in vitro of Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa, as well as bactericidal rates and postantibiotic effects of several antibiotics. However, MICs were reduced at least four-fold by increasing temperature in 25%...
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Standard and clinical strains of Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae were subjected to continuous exposure to β-lactams and aminoglycosides during the postantibiotic effect phase induced by rifampicin or erythromycin (for S. aureus). A significant inhibition of bactericidal activity by these agents during the PAE perio...
Article
A total of ten strains of Candida spp. and Cryptococcus neoformans were examined for the presence of the postantibiotic effect (PAE) after 0.5–2 h exposure to amphotericin B, 5-fluorocytosine, miconazole and ketoconazole. Significant PAEs were observed for amphotericin B and 5-fluorocytosine, but none for the imidazoles. The duration of the PAEs of...
Article
Chlamydia pneumoniae is a newly recognized common cause of respiratory tract infections. The aim of this study was to examine its prevalence in Iceland. The study was based on 1020 serum samples from individuals 0-99 years old. The samples were divided into 10-year age groups. IgG and IgM antibodies were determined with microimmunofluorescence assa...
Article
The post-antibiotic effect (PAE) may allow for more widely spaced dosing of antibiotics than is currently employed without loss of efficacy. Antimicrobial combinations are widely used in clinical medicine. However, dosing schedules are usually based on pharmacological profiles of the drugs used alone. Previously we have demonstrated significant pro...
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Ultrastructural alterations of Staphylococcus aureus and Pseudomonas aeruginosa were examined during the postantibiotic effect (PAE) with transmission electron microscopy. After exposure to dicloxacillin the staphylococci were characterized by an increase in the number of crosswalls, rifampin produced thickening of the cell wall, but only minimal c...
Article
Subjects attending a semi-anonymous HIV testing site at Borgarspitalinn, Reykjavik, during a five year period (1987-1992) were asked to complete a questionnaire on several factors associated with increased risk of HIV infection and the reason for their request of being tested. Serum samples from the subjects were tested for antibodies against HIV,...
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Most studies on pharmacodynamic variables in vitro, including the postantibiotic effect (PAE), are performed at pH 7.4 in noncationic-supplemented media, a situation which may differ significantly from the true microenvironment in most infected foci. We studied the impact of five different pH levels (pH 5, 6, 7, 7.4, and 8) on the duration of the P...
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The duration of the postantibiotic effect (PAE) determined by bacterial CO2 production measured by using the BACTEC NR 730 blood culture system was compared with PAEs determined by standard viability counting. PAEs for Staphylococcus aureus after exposure to dicloxacillin, vancomycin, rifampin, gentamicin, and ciprofloxacin and for Escherichia coli...
Article
A cross-sectional prevalence study of gram-negative bacillary oropharyngeal colonization in the geriatric population with single oropharyngeal cultures was performed on three different groups of individuals, the first consisting of healthy individuals, living independently, the second residing in a nursing facility and the third hospitalized. A lon...
Article
Antimicrobial combinations are frequently needed for the successful treatment of serious infections. Generally, the same dosing schedules are employed irrespective of whether the drugs are used singly or in combination. A postantibiotic effect (PAE) has been described for all antibiotics used singly against Gram-positive cocci, but only for non-bet...
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The new quinolone antibacterial agents have been found to produce a postantibiotic effect (PAE) of 1-4 h in bacteria but the underlying mechanism is still unknown. After exposure to ciprofloxacin in concentrations of 1-16 x MIC for 1 hr the DNA synthesis in S. aureus ATCC 25923 was investigated during the PAE. Ultrastructure was also investigated b...
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Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn Skoða/Opna(view/open) Skútabólga (sinusitis) er algeng sýking fullorðinna, og benda athuganir vestan hafs til að skútabólga fylgi í kjölfar um 0.5% efri loftvegasýkinga. Litlar upplýsingar eru til um tíðni og orsakir sjúkdómsins hérlendis. Tilgangur þessarar athu...
Article
Current antimicrobial dosing regimens are designed to maintain active drug levels for most of the dosing interval and are based on 40-y-old observations. With use of numerous multiple-dosing regimens in an animal model, this study is the first to successfully minimize the interdependence between pharmacokinetic parameters and thereby determine, by...
Article
The postantibiotic effect (PAE) is the suppression of bacterial growth that persists after limited exposure of organisms to antimicrobial agents. Wedemonstrated and standardized the in vivo PAE in a thigh infection model in neutropenic mice. Inhibitors of protein and nucleic acid synthesis induced PAEs of 1.4–7.5 h against aerobic gram-negative bac...
Article
The postantibiotic effect (PAE) in vivo of imipenem, cefoperazone and latamoxef was investigated in a neutropenic mouse thigh model. Two hours after inoculation of 10(6) cfu of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa into each thigh, the neutropenic mice were treated with single doses of 50-200 mg/k...
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Two patients had streptococcal myositis. Both patients developed extensive muscle necrosis and overwhelming sepsis after trivial skin trauma. Death occurred within 48 hours of hospital admission despite aggressive surgical and medical treatment. Review of the literature is included to highlight the fulminant nature of this unusual infection and to...
Article
Netilmicin, the 1-N-ethyl derivative of sisomicin, is a new aminoglycoside antibiotic that was recently marketed in the United States. Its role in therapeutics is not yet established. The pharmacokinetic profile of netilmicin is very similar to that of gentamicin. Its antimicrobial spectrum and clinical efficacy is similar to that of gentamicin, to...
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Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Undanfarna mánuði hafa forvarnir gegn heilsuvanda og sjúkdómum verið nokkuð til umræðu í íslensku samfélagi. Meðal annars hefur verið teflt fram umdeildum sjónarmiðum sem fram hafa komið í nálægum löndum um að forvarnir leiði til oflækninga og hefur þei...
Article
Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Objective: The size of waiting lists has traditionally been viewed as a fairly good measure of the quality of health care services. No statistical analysis exists in Iceland of the length of waiting times and the potential variation between groups of pa...
Article
Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Objective: Dietary fish-oil has beneficial effect in infections and in autoimmune disorders. This effect is thought to be associated with alterations in the immune system. The Gram negative organism Klebsiella pneumoniae has been used as an infective ag...
Article
Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Objective: Fish-oil enriched diet has a protective effect on experimental animals infected intramuscularly with Klebsiella pneumoniae. It also has beneficial effect in several other diseases, including autoimmune disorders. The pathophysiological effect...
Article
Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Objective: Epidemiological studies have indicated that high intake of w-3 fatty acids influence various diseases such as cardiovascular diseases and autoimmune disorders. These fatty acids are essential in the diet since the body can not form them de no...
Article
Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Objective: First to measure plasma HIV-1 RNA in Icelandic HIV infected individuals and second to evaluate the initial effects of new combination regimens on viral load and CD4+ cell counts in HIV infected patients in Iceland. Material and methods: The c...
Article
Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Objective: To describe the application of and analyze the cost effects of antibiotic utilization review at Landspitalinn, the National University Hospital in Iceland, and review the use of prophylactic antibiotics in a general surgical ward. Material an...
Article
Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Objective. To describe the epidemiology of AIDS and HIV infection in Iceland with demographic characteristics and associated risk factors. Design. Survey of national data reported to the Office of the Director General of Public Health in Iceland from No...
Article
Full-text available
Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/Open Introduction: Antibiotics are responsible for 20-25% of the total drug-cost in the larger hospitals in Iceland. Studies from other countries, both in Europe and North-America suggest that 40-70% of both antibiotic therapy and prophylaxis is inappropriat...