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S O Larsen

Publications and source records attributed to S O Larsen.

At least 19 recordsLinked to original sources
PubMed1995

[Occurrence of toxoplasmosis in pregnant women in Denmark. A study of 5.402 pregnant women].

Consecutive serum samples from 5402 women were analyzed for specific IgG and IgM Toxoplasma gondii antibodies by enzyme immunosorbent assay. The prevalence of IgG antibodies was 27.4%. The seroconversion rate was estimated to be 1.16% per year (SE = 0.0017) in all age groups, consistent with an incidence of acute toxoplasmosis in pregnant women of 0.65%. Based on theses figures, the estimated number of congenitally infected cases are discussed. There was no difference in the prevalence of antibodies in women from rural or urban areas, or from different parts of Denmark.

Acute Disease↗
PubMed1995

The role of serum tetranectin, CA 125, and a combined index as tumor markers in women with pelvic tumors.

Serum tetranectin (Se-TN) and CA-125 were measured in 315 patients with a pelvic tumor and 458 healthy females. At a false-positive rate of 0.7% the sensitivity for ovarian cancer stage 1 and 2 was 33% for Se-TN and 76% for both CA 125 and an index based on Se-TN and CA 125 (Index 1). At a false-positive rate of 0.4% the sensitivity was 29% for Se-TN, 62% for CA 125 (35 U/ml), and 76% for Index 1. A negative correlation was found between the Se-TN level and the stage of cancer. The sensitivity for benign tumors was 6% for Se-TN, 17% for CA 125, and 21% for Index 1 at a false-positive rate of 0.4%. In the present study the sensitivity and specificity levels of Se-TN were not sufficiently high to warrant the use of Se-TN as an individual marker for ovarian cancer. The sensitivity rose with the index-based Se-TN and CA 125 without causing a concomitant increase in the rate of false-positive results. None of the markers rose to levels that would allow their use in clinical diagnosis to discriminate between localized cancer and benign tumors.

Adolescent↗
PubMed1994

[Screening of school children for familial hypercholesterolemia].

A total of 3025 families with school children aged six to eight years were offered pilot screening for familial hypercholesterolaemia by measurement of the concentration of apolipoproteins A-1 and B in the children's capillary blood and by analysis of their family histories of early ischaemic heart disease. The concentrations of the apolipoproteins were determined by double rocket immunoelectrophoresis of an eluate of blood spotted on filter paper. Results were available from 2085 children. Because their B:A-1 ratio was above the 97.5 centile and their concentration of B was above the 99th centile, 54 children (2.6%) were selected to have their apolipoprotein concentrations reassessed. The 17 children (0.8%) whose values were persistently above the chosen cut-off points, and all of their available first and second degree relatives, had fasting determinations of serum lipid concentrations carried out. Raised serum concentrations of low density lipoprotein cholesterol and an autosomal dominant pattern of hypercholesterolaemia were found in respectively 12 children and 10 families, suggesting a higher incidence of familial hypercholesterolaemia than the reported 1:500. Further investigations among family members disclosed hypercholesterolaemia in 29 relatives. A family history of early ischaemic heart disease was elicited by questionnaire, and was positive in only five of the 12 school children with hypercholesterolaemia. We conclude that analysis of apolipoproteins from capillary blood spotted on filter paper is suitable for screening for familial hypercholesterolaemia, and that this method is more efficient than screening based on family history.

Apolipoprotein A-I↗
PubMed1994

Epidemiology of pertussis in Denmark: the impact of herd immunity.

BACKGROUND: An evaluation is presented of the Danish pertussis immunization programme, which consists of three injections of plain whole-cell pertussis vaccine given alone at ages 5 weeks, 9 weeks, and 10 months. DATA: The incidence of pertussis in vaccinated and unvaccinated children since the start of vaccination was obtained from the notification system for infectious diseases. Data for vaccination coverage were obtained from the National Social Security. The data for 1980-1986 were supplemented with data from culture-verified cases and hospitalized cases. RESULTS: Compared with other countries using four injections, incidence rates in Denmark are high, especially in pre-school years, leaving infants at a relatively high risk for contracting pertussis from siblings. However, compared with the era before general vaccination, the incidence of pertussis has fallen to one-sixteenth of its former levels. Today, only one in 20 vaccinated, and one in six unvaccinated children develop pertussis before the age of 15 years. This considerable fall, which has also occurred among unvaccinated children, is used to elucidate the importance of herd immunity, which, with the relatively high vaccination coverage in Denmark, was found to play a major role. CONCLUSIONS: The importance of herd immunity is stressed, and it is recommended that a fourth injection of pertussis vaccine is introduced to bring incidence rates down to the very low values found in countries with more intensive vaccination programmes.

Adolescent↗
PubMed1994

Models for prediction of the frequency of toxoplasmosis in pregnancy in situations of changing infection rates.

BACKGROUND: Estimation of the number of women infected during pregnancy with Toxoplasma gondii from seroconversion or seroprevalence data meets with various difficulties. Because of the high risk of transmission of the infection to the fetus such infections are however a major concern in pregnancy-related health planning. METHODS: The expected annual percentage of pregnant women infected with Toxoplasma was calculated using models with varying assumptions with regard to the infection rate, assumed to be independent of age but dependent on calendar time. Three situations were studied: a stable situation, a sudden fall in the infection rate and a gradually declining (slower or faster) infection rate over the lifetime of the pregnant women. RESULTS: With a constant infection rate, a maximum number of affected pregnancies occurs at a yearly infection rate of 4%. In countries with a strongly decreasing annual infection rate, estimates based on data on the relation between age and seropositivity related to only one period of time tend to overestimate the number of affected pregnancies by as much as 60%. CONCLUSIONS: In countries in transition from high to low infection rates, it is likely that the influence of decreasing immunity will, at least temporarily, more than outweigh the influence of the falling infection rates, resulting in a higher number of infected pregnant women. The models used can also describe situations with age-dependent variation in the infection rate, and may well apply to other infectious diseases relevant to pregnancy.

Adult↗
PubMed1994

A new simple and rapid dual assay for AFP and free beta hCG in screening for Down syndrome.

We have evaluated a simple and rapid 2-step dual-label assay (DELFIA) for alphafetoprotein (AFP) and free beta subunit of human gonadotropin (hCG beta) in second-trimester screening for Down syndrome. Based on stored serum samples from 1059 normal control pregnancies and 72 cases of Down syndrome, we have found the mean Multiple of Median (MoM) for AFP and free hCG beta to be 0.70 and 2.31, respectively. This is slightly but not significantly better than the values for the separate assay for AFP (0.76 MoM) and for intact hCG (2.11 MoM). However, the dual assay is much simpler than the separate assays and therefore prospective comparison trials should be carried out.

Chorionic Gonadotropin↗
PubMed1993

A comparison of amniotic fluid alpha-fetoprotein and acetylcholinesterase in the prenatal diagnosis of open neural tube defects and anterior abdominal wall defects.

Amniotic fluid samples received for routine prenatal diagnosis of open neural tube defects were used for a study to compare amniotic fluid acetylcholinesterase (AChE) determination using a monoclonal antibody (4F19) enzyme antigen immunoassay and amniotic fluid alpha-fetoprotein (AFP) measurement as diagnostic tests for open neural tube defects. The study was based on 9964 women with singleton pregnancies and known outcome (including 6 with anencephaly and 18 with open spina bifida) having an amniocentesis at 14-23 weeks of gestation. The AChE immunoassay yielded detection rates for anencephaly of 100 per cent (95 per cent confidence interval (CI) 54.07-100 per cent), for open spina bifida of 100 per cent (95 per cent CI 81.47-100 per cent), for anterior abdominal wall defects of 20 per cent (95 per cent CI 0.51-71.64 per cent), and a false-positive rate of 0.22 per cent (95 per cent CI 0.14-0.34 per cent) excluding anencephaly, open spina bifida, and anterior abdominal wall defects. For similar detection rates the false-positive rate of the AFP test was significantly higher, 0.74 per cent (95 per cent CI 0.58-0.94 per cent). On the basis of these findings, it is recommended that the technically simple AChE immunoassay should be used on all samples; the AFP test should only be used on the 0.5 per cent of the samples with concentrations of AChE activity > or = 8.5 nkat/l for clear samples and blood-stained samples becoming clear after centrifugation, and > or = 25.0 nkat/l for blood-stained samples that are discoloured after centrifugation; an AFP cut-off level of 2.0 MOM is recommended for this policy. Thereby, the detection rates for anencephaly, open spina bifida, and anterior abdominal wall defects would be 100, 100, and 20 per cent, respectively (95 per cent CIs 54.07-100, 81.47-100, and 0.51-71.64 per cent, respectively), and the false-positive rate would be 0.08 per cent (95 per cent CI 0.03-0.16 per cent) (excluding anencephaly, open spina bifida, and anterior abdominal wall defects).

Abdominal Muscles↗
PubMed1993

Management of urinary bladder function in Danish hospitals, nursing homes and home care.

The purpose of this study was to determine the prevalence of the various devices used for bladder function management in Denmark and to assess the scope for the use of alternatives to the indwelling urethral catheter. Data were collected on 1581 hospital patients, 1341 nursing home residents and 743 patients receiving home care. The sample populations were characterized by age, sex and independence in the activities of daily living. The prevalence of indwelling catheters in the three groups of patients was 13.2%, 4.9% and 3.9%, respectively. The equivalent figures for condom drainage systems were 1.5%, 0.8% and 1.2%, and for napkins 10.1%, 52.1% and 34.1%. Comparison of the results from this survey with earlier data indicates that over the period 1980-1991 (during which efforts have been made in Denmark to restrict indwelling bladder catheterization and encourage the use of alternative devices) there has been a reduction in the prevalence of indwelling catheters in hospital medical wards from 13.7% to 6.6%. Examination of the reasons for catheterization revealed that the proportions of patients catheterized because of incontinence were 14% in hospitals, 31% in nursing homes and 33% in home care. There is clearly a need to continue the educational efforts to inform staff of the infection risks and complications associated with indwelling catheters and persuade them of the advantages of the alternative techniques for care of the incontinent patient.

Activities of Daily Living↗
PubMed1993

Use of gloves and handwashing behaviour among health care workers in intensive care units. A multicentre investigation in four hospitals in Denmark and Norway.

Glove use and handwashing frequencies (HW) were observed in intensive care units (ICU) in two university hospitals in Denmark and two in Norway. The study included a total of 1632 patient procedures performed by 325 persons. Handwashing (HW) has become an important part of general barrier precautions. Earlier studies have shown that health care workers (HCW) far too often neglect to wash their hands after patient procedures when handwashing is strongly recommended. Despite earlier claims that increased glove use in hospitals would discourage handwashing, our results showed that HCW washed their hands more often after glove use (57%) than when gloves had not been used (40%). This significant difference in HW frequency was also noted when similar procedures were carried out by HCW with or without gloves. This might be a matter of personal discomfort after wearing gloves, but could also be due to differences in awareness of hygienic aspects of patient care. In the two countries gloves were used on average at 17% of the procedures, but were not used appropriately for dirty procedures. The results of this study indicate that more effective methods for the implementation of appropriate glove use and HW should be emphasized.

Denmark↗
PubMed1993

Prevalence, incidence and geographical distribution of Toxoplasma gondii antibodies in pregnant women in Denmark.

The purpose of this study was to determine the prevalence and incidence of toxoplasmosis in pregnant women in Denmark, and to estimate the incidence of congenital toxoplasmosis. Consecutive serum samples from 5,402 women were analysed for specific IgG and IgM Toxoplasma gondii antibodies by EIA. The prevalence of IgG antibodies was 27.4%. The seroconversion rate was estimated to be 1.16% per year (SE = 0.0017) in all age groups, consistent with an incidence of acute toxoplasmosis in pregnant women of 0.65%. Specific IgM antibodies were present in sera from 29 women. Based on an assumed maternofetal transmission rate of 50%, the incidence of congenital toxoplasmosis was estimated to be 0.33%. Based on these data it is predicted that about 410 pregnant women are infected with T. gondii every year in Denmark, and that about 200 children every year are infected in utero by T. gondii. There was no difference in the prevalence of antibodies in women from rural or urban areas, or from different parts of Denmark.

Adolescent↗
PubMed1993

Simultaneous assay of alpha-fetoprotein and free beta subunit of human chorionic gonadotropin by dual-label time-resolved immunofluorometric assay.

We developed a simple, rapid two-step dual-label assay for the noncompetitive determination of alpha-fetoprotein (AFP) and beta subunit of human chorionic gonadotropin (hCG beta) in serum. Monoclonal antibodies to detect AFP and hCG beta were labeled with europium (Eu) and samarium (Sm), respectively. Highly fluorescent chelates were developed by using the Delfia enhancement principle. The detection limits for AFP and hCG beta were approximately 0.02 kIU/L and approximately 0.2 IU/L, respectively. The within-run precision was < 5% over the whole range of AFP (1-500 kIU/L) and hCG beta (1-200 IU/L) concentrations tested. Cross-reaction of intact hCG was < 0.03%. The AFP concentrations determined with the dual-label assay correlated well with those obtained by Delfia AFP single-label kit. The concentrations of hCG beta were in good agreement with recently published data. Storing the serum samples for 24 h or 1 week at room temperature increased the hCG beta concentration by 4% and 26%, respectively. At 35 degrees C this dissociation of hCG increased 30-40-fold. Repeated freezing and thawing had no effect on the hCG beta concentration.

Antibodies, Monoclonal↗
PubMed1992

[Extent of HIV infection and AIDS among drug addicts].

The purpose of this study was to review the extent of the HIV-epidemic and to make a prognosis about the number of AIDS-cases among drug addicts in the community of Copenhagen. In the public institutions for treatment of drug addicts, 191 HIV-positive individuals were known by January 1991. In the period August 1990-November 1991, 33 newly recognized cases of seropositivity were registered among drug addicts in the area of Copenhagen, but the time of infection was unknown. By October 1991, 53 cases of AIDS among drug addicts in Denmark were recorded. Based upon the knowledge of incubation period and mortality of AIDS, it was possible to set up a mathematical model, from which the number of expected AIDS-cases could be estimated. This model showed that the number of living drug addicts with AIDS in the community of Copenhagen probably not will exceed 20 during the coming years. It was also showed, that the number of drug addicts, who were infected with HIV in the primary spread of the virus in 1985-1986, was probably lower than 250. The actual prevalence and incidence of HIV-infection among drug addicts is uncertain, and there is a need for better surveillance of the epidemic.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Elimination of human chorionic gonadotropin in serum and urine after uncomplicated induced abortion during the first trimester].

Serum chorion gonadotropin was measured weekly in 12 women from the time of legal first trimester abortion until values were below 10 IU/L. The elimination followed a 2-component curve. The half-life in the first few days was 1.1 day, hereafter 4.2 days. Serum-HCG decreased to less than 10 IU/L within 22 to 40 days. The elimination of serum-HCG was found to decrease so uniformly, that values which do not decrease must be considered abnormal. A sensitive bedside urine-HCG test was found to be positive from 13 to 31 days after the abortion.

Abortion, Induced↗
PubMed1992

CA-125 as a maternal serum marker for Down's syndrome in the first and second trimesters.

CA-125, alpha-fetoprotein (AFP), and human chorionic gonadotropin (HCG) were determined in maternal serum in the first trimester from 14 women with a Down's syndrome fetus and 61 women with a healthy fetus. In the second trimester, 15 and 60 serum samples were determined from women with a Down's syndrome and a healthy fetus respectively. In both trimesters, maternal serum CA-125 was found to be elevated in Down's syndrome pregnancies compared with controls. Using discrimination functions, our preliminary results indicate that CA-125 is a better marker than AFP and HCG respectively for a Down's syndrome fetus in the first trimester and improves the detection rate in the second trimester.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1992

A multicenter questionnaire investigation of attitudes toward hand hygiene, assessed by the staff in fifteen hospitals in Denmark and Norway.

A questionnaire survey was carried out anonymously among 2557 health care workers in Denmark and Norway to identify and quantify factors that affect the handwashing behavior of physicians, nurses, and other staff groups who perform direct patient care. For number of daily patient contacts physicians reported significantly fewer instances of hand hygiene (HH) per day than did those in other medical professions. Male physicians reported significantly fewer HH per day than did their female colleagues. Significant differences were found among staff groups in emphasis on factors motivating and discouraging HH. The main motivating factor for all groups, however, was an awareness that HH is important for the prevention of infection. Skin problems from frequent handwashing and the use of agents that irritate and dry the skin were the main reasons for disinclination toward HH. The number of points given to these statements correlated well with the stated frequency of HH in staff groups with relatively many (9 to 24) patient contacts per day. Many studies have revealed low standards of HH in health care settings. Whenever HH is taught, the significance of HH for the prevention of infection is always stressed. The participants in this survey were well aware of this significance, but there is still a discrepancy between theory and practice. Goal-specific strategies to improve HH practices would probably be more effective if more were done to minimize the factors that health care workers find detrimental to HH. Continual evaluation of the possibly detrimental effects of current hand washing agents should also be carried out.

Attitude of Health Personnel↗
PubMed1992

Rate-limiting components and reaction steps in complement-mediated haemolysis.

The aims of this study were to identify the rate-limiting components and reaction steps in the integrated activation sequence of the alternative (AP) and classical (CP) pathways of the complement (C) system. In an initial correlation analysis we found that the haemolysis rate in AP was correlated with the concentrations of C5 and IgM. In CP, the haemolysis rate was correlated with the concentrations of C2-C6, factors I and B, and IgM. In order to identify the rate-limiting components, we added single, purified C components and IgM to pooled, normal human serum and measured the resultant change in the haemolysis rate. We found that a large number of different components, rather than a single one, were rate-limiting in AP and CP. In reconstitution experiments we found that in CP the rate-limiting reaction steps are the activation of C4 and C2. In AP we cannot identify the rate-limiting step precisely, but can only state that it is at the C3 activation step or earlier.

Adolescent↗
PubMed1992

Comparison of detection speed and yield in agitated and non-agitated aerobic blood culture bottles.

The influence of agitation on detection speed and yield was evaluated in 7,033 paired, identical aerobic blood culture bottles (Media Department, Statens Seruminstitut, Copenhagen, Denmark). One bottle was agitated and the other was incubated stationary. Of a total of 943 organisms isolated in aerobic blood culture bottles, 74% were clinically significant. No difference in the total yield of significant organisms was observed between agitated and non-agitated bottles. In the evaluation of detection speed, only cultures where organisms were isolated from both bottles, but at different times, were included, to ensure that no other factors influenced the result. Staphylococci, Pseudomonas spp., and Candida spp. were detected significantly faster in agitated bottles, on average 0.5-1 day earlier (p < 0.05), and in the majority of the cases within the first incubation day. These species are frequently found and are important causes of severe generalized infections, especially in immunocompromised patients, where early detection is of great importance. The detection principle in agitated bottles in our system, darkening of blood, proved to be an easy, reliable, and fast method to detect positive aerobic blood cultures, which could probably lead to increased automation.

Aerobiosis↗