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Bjørn Myrvang

Publications and source records attributed to Bjørn Myrvang.

At least 19 recordsLinked to original sources
PubMed2006

[Histoplasmosis among travellers to Central America].

BACKGROUND: In April 2004, the Norwegian Institute of Public Health was notified about an outbreak of a respiratory illness among participants on a cultural-historical theme tour to Central America. One patient was examined in a Swedish hospital where the clinician suspected histoplasmosis, which later was verified by serology and by culture of Histoplasma capsulatum. In order to describe the outbreak and identify the possible source of infection, a clinical and epidemiological study was conducted. MATERIAL AND METHODS: A questionnaire on symptoms, treatment and participation in various activities was sent to all the tour participants. Reminders were sent by e-mail. In addition, some participants underwent a more detailed clinical examination. RESULTS: 19 of the 21 travellers completed the questionnaire. All travellers had visited several caves inhabited by bats in El Salvador and Guatemala. During the last 10 days of the journey, 16 of the respondents (84%) acquired a respiratory illness that lasted for more than 3 weeks. The diagnosis was confirmed by serology in 8 of the 14 tested cases. Antibacterial therapy was given to 11 patients and antifungal therapy to 3 patients. Only one patient was hospitalised. INTERPRETATION: The described outbreak of histoplasmosis was probably caused by exposure to Histoplasma capsulatum during a visit in bat-infested caves. Due to the increasing popularity of adventure and theme travels, this disease may become more frequent in our population. The condition should be considered in travellers with prolonged respiratory illness after visits to caves or other closed environments with little circulation of air that are potentially contaminated with bat or bird droppings. Persons with immunosuppression may develop severe illness, and should consider avoiding places with increased risk.

Adult↗
PubMed2006

Increased levels of soluble CD40L in African tick bite fever: possible involvement of TLRs in the pathogenic interaction between Rickettsia africae, endothelial cells, and platelets.

The pathophysiological hallmark of spotted fever group rickettsioses comprises infection of endothelial cells with subsequent infiltration of inflammatory cells. Based on its ability to promote inflammation and endothelial cell activation, we investigated the role of CD40L in African tick bite fever (ATBF), caused by Rickettsia africae, using different experimental approaches. Several significant findings were revealed. 1) Patients with ATBF (n = 15) had increased serum levels of soluble CD40 ligand (sCD40L), which decreased during follow-up. 2) These enhanced sCD40L levels seem to reflect both direct and indirect (through endothelial cell activation involving CX3CL1-related mechanisms) effects of R. africae on platelets. 3) In combination with sCD40L, R. africae promoted a procoagulant state in endothelial cells by up-regulating tissue factor and down-regulating thrombomodulin expression. 4) Although the R. africae-mediated activation of platelets involved TLR2, the combined procoagulant effects of R. africae and sCD40L on endothelial cells involved TLR4. 5) Doxycycline counteracted the combined procoagulant effects of R. africae and sCD40L on endothelial cells. Our findings suggest an inflammatory interaction between platelets and endothelial cells in ATBF, involving TLR-related mechanisms. This interaction, which includes additive effects between sCD40L and R. africae, may contribute to endothelial inflammation and hypercoagulation in this disorder.

Adult↗
PubMed2006

Sub-acute neuropathy in patients with African tick bite fever.

African tick bite fever (ATBF) caused by Rickettsia africae is an emerging health problem in travellers to sub-Saharan Africa. We here present 6 patients with evidence of long-lasting sub-acute neuropathy following ATBF contracted during safari trips to southern Africa. Three patients developed radiating pain, paresthaesia and/or motor weakness of extremities, 2 had hemi-facial pain and paresthaesia, and 1 developed unilateral sensorineural hearing loss. When evaluated 3-26 months after symptom onset, cerebrospinal fluid samples from 5 patients were negative for R. africae PCR and serology, but revealed elevated protein content in 3 and mild pleocytosis in 1 case. Despite extensive investigations, no plausible alternative causes of neuropathy could be identified. Treatment with doxycycline in 2 patients had no clinical effect. Given the current increase of international safari tourism to sub-Saharan Africa, more cases of sub-acute neuropathy following ATBF may well be encountered in Europe and elsewhere in the y to come.

Adult↗
PubMed2006

Heterogeneity of Mycobacterium tuberculosis isolates in Sunamganj District, Bangladesh.

A total of 111 Mycobacterium tuberculosis isolates from new pulmonary tuberculosis patients, living in the rural Sunamganj district in northern Bangladesh were characterized with IS6110 restriction fragment length polymorphism analyses and spoligotyping. Only 3 of the isolates belonged to the W-Beijing genotype of M. tuberculosis. A high degree of diversity indicated that the spread of M. tuberculosis, in this rural area, was not caused by closely related genotypes. The tuberculosis cases in the current study were less likely to represent recent transmission than what is commonly observed in urban parts of south-east Asia. It was indicated that the tuberculosis cases of this isolated area, of a high-incidence country, represented those of an established epidemic, not yet influenced by recently disseminated strains.

Bangladesh↗
PubMed2005

Repellent efficacy of four commercial DEET lotions against Amblyomma hebraeum (Acari: Ixodidae), the principal vector of Rickettsia africae in southern Africa.

African tick bite fever, caused by Rickettsia africae, is an emerging zoonotic infection in rural sub-Saharan Africa and the French West Indies. We tested the repellent efficacy of four commercial diethyl-3-methylbenzamide (DEET) lotions against Amblyomma hebraeum Koch, the principal vector of R. africae in southern Africa, by using a human bioassay in which repellent-treated fingers were presented to questing tick nymphs hourly for 4h. Three lotions with 19.5, 31.6 and 80% DEET concentrations, respectively, had a repellent efficacy of > or =90% at 1h post-application, of > or =77% at 2h post-application and of <70% during the rest of the experiment. By contrast, a lotion with 2% DEET plus 1% citronella oil provided only a 59% repellency at 1h post-application, with a drop to <22% during the following hours. Hourly negative control trials repelled <5% of tick attacks. Our results suggest that commercial repellents containing > or =19.5% DEET provide a significant but short-lasting protection against questing A. hebraeum ticks.

Administration, Topical↗
PubMed2005

Fascioliasis imported to Norway.

We report 3 cases of fascioliasis imported to Norway: a 24-y-old male Vietnamese immigrant and a 51-y-old female Vietnamese immigrant with acute fascioliasis, and a 2-y-old male Ethiopian adoptee with chronic fascioliasis. Diagnosis was confirmed by detection of specific antibodies to Fasciola hepatica in the 2 first cases and by demonstration of Fasciola hepatica eggs in stool samples in the latter case. Treatment with oral triclabendazole led to prompt cure in all 3 patients. Imported fascioliasis is rarely reported but should be suspected in patients with a travel history to endemic areas, abdominal symptoms and hypereosinophilia of the blood.

Adult↗
PubMed2004

Treatment with pegylated interferon and ribavarin in HCV infection with genotype 2 or 3 for 14 weeks: a pilot study.

The aim of this study was to determine the efficacy of 14 weeks of treatment in patients infected with hepatitis C virus (HCV) genotype 2 or 3 who achieve early virological response (EVR). In a noncontrolled multicenter trial, 122 treatment-naive patients received 1.5 mug/kg pegylated interferon alfa-2b subcutaneously once weekly and 800 to 1,400 mg/d ribavirin based on body weight. Treatment was stopped at week 14 in patients with EVR, defined as undetectable HCV RNA at weeks 4 and 8. Patients without EVR were assigned to 24 weeks of treatment. The primary end point was sustained virological response (SVR), defined as undetectable HCV RNA 24 weeks after end of treatment. Among the 122 patients, 95 (78%) had EVR and received 14 weeks of treatment. The remaining 27 (22%) were treated for 24 weeks. SVR was obtained in 85 (90%) of 95 patients in the 14-week treatment group and 15 of (56%) 27 in the 24-week treatment group. Altogether, SVR was obtained in 100 of 122 patients (82%; 95% CI, 75%-89%). SVR after 14 weeks of treatment was achieved more frequently among genotype 3a patients with low viral load compared with high viral load (98% vs. 79%; P = .019). Logistic regression analysis showed that absence of bridging fibrosis/cirrhosis was the only independent predictor of SVR. In conclusion, patients with genotype 2 or 3 and EVR obtained a high SVR after 14 weeks of treatment. The results need to be confirmed in a randomized, controlled study before this treatment approach can be recommended, particularly for patients with genotype 3 and high viral load or severe fibrosis.

Adult↗
PubMed2004

Comparison of immunofluorescence, Western blotting, and cross-adsorption assays for diagnosis of African tick bite fever.

In testing paired serum samples from 40 consecutive cases of African tick bite fever, we detected diagnostic antibodies against spotted fever group rickettsiae in 45% of the patients by immunofluorescence assay (IFA) and in 100% of the patients by Western blotting (WB) (P < 0.01). A specific diagnosis of Rickettsia africae infection could be established in 15% of the patients by IFA and in 73% of the patients by a combination of WB and cross-adsorption assays (P < 0.01).

Adolescent↗
PubMed2004

Criminality in drug addicts: a follow-up study over 25 years.

UNLABELLED: BACKGROUND/AIMS/METHOD: 214 drug addicts were included in a 25-year study on criminality using data from the National Register of Convictions, and 84% of those still living in Oslo attended a follow-up examination. RESULTS: 89% of the 214 had committed offences, compared to 25% in a control group without drug use. 83% had been imprisoned. Males showed more criminal behavior than females and committed the most serious crimes. Male gender and more than two convictions were risk factors for reduced survival. At the follow-up examination 65% had abandoned illegal drugs and the majority had simultaneously stopped their criminal activities. There were significantly less drug offenders, thieves and people committing fraud or violations of traffic laws among the former drug addicts, but not less violent criminals. Criminality diminished with increasing age. CONCLUSIONS: Drug addicts were heavily involved in criminal affairs. Abandonment of illegal drugs and increasing age were associated with discontinuation of criminality.

Adult↗
PubMed2003

African tick bite fever in travelers to rural sub-Equatorial Africa.

To estimate the incidence of, identify risk factors for, and describe the clinical presentation of travel-associated African tick bite fever (ATBF), a rapidly emerging disease in travel medicine, we prospectively studied a cohort of 940 travelers to rural sub-Equatorial Africa. Diagnosis was based on suicide polymerase chain reaction and the detection of specific antibodies to Rickettia africae in serum samples by multiple-antigen microimmunofluorescence assay, Western blotting, and cross-adsorption assays. Thirty-eight travelers, 4.0% of the cohort and 26.6% of those reporting flulike symptoms, had ATBF diagnosed. More than 80% of the patients had fever, headache, and/or myalgia, whereas specific clinical features such as inoculation eschars, lymphadenitis, cutaneous rash, and aphthous stomatitis were seen in < or = 50% of patients. Game hunting, travel to southern Africa, and travel during November through April were found to be independent risk factors. Our study suggests that ATBF is not uncommon in travelers to rural sub-Saharan Africa and that many cases have a nonspecific presentation.

Africa↗
PubMed2003

Systemic inflammatory responses in African tick-bite fever.

Information regarding the inflammatory response in African tick-bite fever (ATBF), an emerging spotted-fever-group rickettsiosis, in international travelers to sub-Saharan Africa, is scarce. Plasma/serum levels of von Willebrand factor (vWF), soluble (s) E-selectin, tumor necrosis factor-alpha, interleukin (IL)-6, interferon-gamma, IL-10, IL-13, IL-8, RANTES, macrophage inflammatory protein-1alpha, and C-reactive protein were studied, at both first presentation and follow-up, in 15 patients with travel-associated ATBF and in 14 healthy travelers who served as control subjects. Our main and novel findings are the following: (1) patients with ATBF had increased levels of vWF and sE-selectin, with a subsequent decrease at follow-up; (2) with the exception of IFN-gamma, levels of cytokines and chemokines were also increased in these patients at the first presentation; and (3) IL-10 and IL-13 tended to increase during follow-up, whereas most of the inflammatory cytokines decreased. The induction of these mediators and the balance between them may be critical both for the regulation of inflammation and for protective immunity in ATBF.

Adult↗
PubMed2003

African tick bite fever.

African tick bite fever is an acute febrile illness that is frequently accompanied by headache, prominent neck muscle myalgia, inoculation eschars, and regional lymphadenitis. The disease is caused by Rickettsia africae, a recently identified spotted fever group rickettsia, which is transmitted by ungulate ticks of the Amblyomma genus in rural sub-Saharan Africa and the French West Indies. Whereas reports on African tick bite fever in indigenous populations are scarce, the number of reported cases in travellers from Europe and elsewhere has recently increased significantly. Treatment with doxycycline is associated with rapid recovery in most patients. An immunofluorescence assay is recommended for the diagnosis but seroconversion is commonly delayed and this limits the usefulness of the test. Travellers to endemic areas should be informed of the risk of contracting African tick bite fever and be encouraged to take personal protective measures against tick bites.

Adult↗
PubMed2003

Risk factors for drug addiction and its outcome. A follow-up study over 25 years.

The aim of the study was to investigate factors related to initiation and abandonment of illegal drugs. A follow-up study on 53 drug addicts originally hospitalized because of parenterally acquired hepatitis was performed using questionnaires. The majority stated that curiosity and peer pressure were the main reasons for starting drug use. Family conflicts, school and mental problems were each reported by about 40% of the subjects. Thirty-nine patients (74%) had abandoned addictive drugs during the approximately 25 years that had elapsed since the hospital stay. All of these thought that own efforts had been most important in this achievement. Other important factors were help and support from family and friends, establishing a family or experiencing acute hepatitis or an overdose.

Adult↗
PubMed2003

A 25-year follow-up study of drug addicts hospitalised for acute hepatitis: present and past morbidity.

The aim of the study was to investigate present and past morbidity in drug addicts, 25 years after hospitalisation for acute hepatitis B or hepatitis nonA-nonB. The hospital records for 214 consecutively admitted patients were analysed, and a follow-up study on 66 of the 144 patients still alive was performed. At follow-up, 1 of 54 (1.8%) hepatitis B patients was still HBsAg positive. Twelve patients originally diagnosed as hepatitis nonA-nonB were all among 54 found to be anti-hepatitis C virus (anti-HCV) positive, and the total anti-HCV prevalence was 81.8%. Twelve (22.2%) of the HCV cases were unknown before the follow-up examination. Four (6.1%) participants were anti-human immunodeficiency virus positive, only 1 was on antiretroviral therapy, and none had developed AIDS. Other chronic somatic diseases were a minor problem, whereas drug users reported skin infections as a frequent complication. Forty-three patients (65%) had abandoned addictive drugs since the hospital stay. Serious mental disorders were reported by 19 patients (28.8%), and 17 (25.8%) regarded themselves as present (9) and former (8) compulsive alcohol drinkers. A large proportion of the participants were granted disability pension (39%), a majority because of psychiatric disorders, drug and alcohol abuse.

Acute Disease↗
PubMed2002

[African trypanosomiasis--a rare imported disease].

This year at least nine cases of African trypanosomiasis have occurred among Europeans visiting the Serengeti Park in Tanzania. One of them was a 26-year-old Norwegian woman who was bitten by a tsetse fly in her face. She developed fever, nausea and other symptoms, and had thrombocytopenia and pathological liver values; trypanosoma parasites were demonstrated in her blood. The recommended drug, suramin, was not readily available in Tanzania and she was transported to Oslo. The diagnosis was confirmed. She had no affection of the central nervous system and was treated successfully with suramin only. Increased tourist traffic to exotic destinations may lead to more frequent import of trypanosomiasis to European countries. Drugs to treat the disease must be readily available.

Adult↗