Lennart Boström
Karolinska Institutet
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Featured researches published by Lennart Boström.
Inflammatory Bowel Diseases | 2003
Afsar Rahbar; Lennart Boström; Ulla Lagerstedt; Inger Magnusson; Cecilia Söderberg-Nauclér; Vivi-Anne Sundqvist
Recent reports have focused interest on human cytomegalovirus (HCMV) in inflammatory bowel diseases (IBD). Our aim in this study was to examine the frequency of HCMV-infected intestinal cells in tissue sections obtained from patients with IBD, and to investigate if HCMV-infected intestinal cells produce the proinflammatory cytokine IL-6. We studied intestinal tissue sections from 13 patients with ulcerative colitis, 10 with Crohns disease, 10 cancer patients without intestinal inflammation, and 10 samples from HCMV-infected AIDS patients. HCMV-DNA was detected by in situ hybridization in sections obtained from 12/13 patients with ulcerative colitis, in 10 with Crohns disease, in 10/10 samples from HCMV-infected AIDS patients, but not in any of the 10 samples that were obtained from uninflamed tissues. HCMV-specific antigens were detected in samples from all HCMV-infected AIDS patients, in 11/13 sections from patients with ulcerative colitis, in 10/10 samples from patients with Crohns disease, but not in sections from uninflamed tissues. Cells were double positive for an HCMV early antigen and IL-6 in 10/13 sections from patients with ulcerative colitis, in all patients with Crohns disease, and in 4/10 samples from AIDS patients. In conclusion, these results suggest that active HCMV infection in the intestine is very frequent in patients with IBD, and may contribute to the inflammatory process through an increased production of IL-6.
Journal of Trauma-injury Infection and Critical Care | 2001
Lennart Boström; Bo Nilsson
BACKGROUND Injured cyclists are often seen in emergency departments. The aims of this study were to determine the long-term incidence of injuries, age and gender distributions, mortality rates, and geographic differences among all patients admitted to hospitals because of bicycle accidents in Sweden. METHODS Between 1987 and 1994, 34,606 persons (39,183 admissions) were injured in bicycle accidents in Sweden (19,978 men and 14,628 women). RESULTS The annual frequency of hospital admissions ranged from 4,585 to 5,212. Fifty-seven patients were admitted with bicycle-related injuries per 100,000 population each year. Children between 5 and 14 years of age, especially boys, and men older than 70 were more commonly involved. Injuries to the head and brain were very frequent (46%). The survival rate was poorest in persons of older age, male gender, and cyclists involved in collisions with motor vehicles. CONCLUSION About 4,900 cyclists have been hospitalized each year after bicycle accidents in Sweden. Young children were affected very often, with injuries of the brain and various types of fractures of the extremities being common. Significant factors for a poor survival outcome included old age, male gender, and collisions with motor vehicles.
Journal of Autoimmunity | 2006
Afsar Rahbar; Lennart Boström; Cecilia Söderberg-Nauclér
Abstract Recent evidence suggests an association between inflammatory bowel disease (IBD) and human cytomegalovirus (HCMV) infection, but the exact pathogenic role of HCMV in this disease remains unclear. HCMV infection has for a long time been known to be associated with various autoimmune manifestations and the formation of autoantibodies. Previous studies from our group have shown that HCMV is associated with a human protein, CD13 (aminopeptidase N) and that autoantibodies against this protein are frequently found in HCMV infected bone marrow transplant patients with chronic graft versus host disease. We have recently observed that 90% of IBD patients have an active HCMV infection. In this study, we examined the presence and cytotoxicity of CD13-specific autoantibodies in sera obtained from 28 patients with ulcerative colitis and 26 patients with Crohns disease, and in sera obtained from healthy blood donors by using flow cytometric assays against mouse cells transfected with human CD13 or a microcytotoxicity assay against different CD13 positive human cells. Cytotoxic CD13-specific autoantibodies were identified in 66% of the sera obtained from HCMV-IgG positive patients with ulcerative colitis and in 58% of the sera obtained from HCMV-IgG positive patients with Crohns disease, but not in control individuals. These cytotoxic autoantibodies may interfere with biological cell functions and could thereby contribute to the chronic inflammation in patients with IBD.
European Journal of Surgery | 2000
Lennart Boström; Göran Heinius; Bo Nilsson
OBJECTIVE To evaluate the incidence, types of injury, medical consequences, and mortality of patients with stab wounds in Sweden. DESIGN Retrospective case study. SETTING The Swedish National Hospital Discharge Register (SNHDR) and the Register of Causes of Death, Statistics Sweden (RCDSS) SUBJECTS: 1315 patients with stab wounds. All 1507 episodes were treated in Swedish hospitals from 1987-1994. MAIN OUTCOME MEASURES Incidence of stab wounds in Sweden, mortality, types of injuries and medical consequences. RESULTS From 1987 to 1994, 1315 people were admitted to Swedish hospitals with stab wounds, which corresponds to 2.1 injuries/100,000 population/year. In all, 1507 episodes were treated in hospital. There were 1121 men (85%) and 194 women (15%), with a median age of 32 years (range 1-88). The annual incidence was relatively constant during this period. The total number of deaths was 45/1315 (3.4%). Among these, 13 (29%) had thoracic, 9 (21%) abdominal, 7 (16%) head/neck and 7 (15%) extremity injuries. Twenty percent of those admitted to hospital had to spend more than one week there. CONCLUSIONS The incidence of stab wounds was low and the annual incidence stable. Young men in urban areas were the commonest victims. Injuries of the trunk were commonest, followed by injuries to the head and neck and limbs, 80% of the patients were discharged from hospital within a week, and 3% of those treated in hospital for stab wounds died.
Archives of Orthopaedic and Trauma Surgery | 1997
Lennart Boström
This retrospective study describes assaults, type of trauma, injury panorama, the abbreviated injury scale score and medical consequences for 1158 assaulted persons. All patients were examined by surgeons at the Emergency Department, Sabbatsbergs Hospital, Stockholm, Sweden, which is open around the clock. The police were not notified. The study group included all assaulted patients who attended and were examined at the Emergency Department from 1 April 1992 to 31 March 1993: 84% men and 16% women. Their median age was 25 years (range 13–86 years). Sixty-eight percent arrived at the Emergency Department between 11 p.m. and 4 a.m. In 44% the hospital staff registered in the case notes that the victims were drunk. Blunt trauma of low-energy type predominated, 44% were hit by fists and 30% by kicks. Penetrating trauma occurred in 10% of the assaults (knife 8%), and a combination of blunt and/or cutting trauma (bottle/glass) in 10%. Eighty-two percent of the victims suffered an injury to the head, resulting in concussion in 116 cases, 4 skull fractures, 1 intracerebral contusion, 74 fractures of nose bones, 17 fractures of other face bones, and 6 mandible fractures. Two persons died because of knifestab wounds. Eighty-two percent of the victims had minor injuries, and 16% had moderate injuries according to the score on the Abbreviated Injury Scale (AIS). The present study shows that assault in the central part of Stockholm, Sweden, is mainly a problem involving young men, especially late in the evening, and that many of the victims are drunk. Injuries to the head due to low-energy trauma are the most common (hit by fists and kicks), but severe injuries seldom occur.
Journal of Gastrointestinal Surgery | 2006
Stefan Linder; Lennart Boström; Bo Nilsson
Progress has been made during the last few decades in the treatment of patients with pancreatic cancer. In this population-based study, the time trends in curative surgery and the choice of palliative invasive therapies in Sweden over two decades are analyzed. Patients treated for pancreatic carcinoma in Sweden during 1980–2000 were identified in the Swedish Hospital Discharge Register and the Cancer Register. These data were matched with those in the Register of Causes of Death in Sweden. Data were identified and analyzed for 16,758 patients for three periods: 1980–1986 (n=5775), 1987–1993 (n=6096), and 1994–2000 (n=4887). The rate of pancreatic resection increased 7.2%, 10.9%, and 15.1% (P<0.0001) during the three respective periods. Palliative interventions decreased from 46.8% in the first period to 41.7% in the last period. On comparing the first and the last periods, biliary bypass operations were found to decrease (from 45.9% to 18.1%), as well as gastric bypass procedures (from 33.8% to 22.8%; P<0.0001). Interventions by percutaneous transhepatic cholangiography (PTC) remained constant (10%–11%). Endoscopic therapy increased from 10.8% to 49.0%, as did the number of procedures per patient, from 1.3 to 1.7 (P<0.0001) in the first and last periods, respectively. In 1980, the mean hospital stay was 40 days after resection and 30 days after palliative intervention. In 2000, the corresponding numbers were 26 days and 18 days (P<0.001), respectively. During the past two decades, the rate of pancreatic resections in Sweden increased significantly. There was also a dramatic drop in palliative open surgery and a simultaneous increase in endoscopic interventions. Hospital stays decreased by more than a third.
Journal of Trauma-injury Infection and Critical Care | 1999
Andreas Wladis; Lennart Boström; Bo Nilsson
BACKGROUND Physical abuse and assault are common problems in the Western hemisphere. The aims of this study were to investigate the injury incidence, distribution of injuries, the age and sex distribution, and the geographical differences in all patients admitted to Swedish hospitals between 1987 and 1994 because of injuries related to unarmed assault. METHODS Patients admitted to hospitals in Sweden between 1987 and 1994 after physical abuse were included in the Swedish Hospital Discharge Register. A description of the types of injuries, surgical procedures, and lengths of hospital stay are presented. The change in the incidence of hospital admissions for unarmed violence-related injuries was evaluated. Linear regression analysis was used to correlate population density with incidence of hospital admission and to evaluate the change in age-standardized incidence of hospital admissions over time. RESULTS Information was available on 17,453 persons, of whom 79% were males. The mean age was 30 years. Craniocerebral injury was the most common (72%) followed by injuries to the extremities (10%), thorax (5%), and abdomen (3%). The mean in-hospital stay was 3 days. Thirty-eight people (0.2%) died of their injuries. The age-standardized incidence of hospital admissions increased significantly over the years in males, but not in females. No correlation was detected between population density and incidence of injury. CONCLUSION Young males are at the greatest risk of incurring physical injuries from assaults that warrant hospital admission, and the incidence in this group has increased significantly. Injuries to the head are the most common. Fatal injuries are rare. The in-hospital stay is usually brief. The frequencies of assaults are similar in urban and rural areas.
European Journal of Surgery | 2002
Andreas Wladis; Lennart Boström; Bo Nilsson
OBJECTIVE To discover morbidity and mortality rates after motor-cycle crashes on the national level in Sweden. DESIGN Retrospective study. SETTING Teaching hospital, Sweden. INTERVENTIONS Extraction of data from International Classification of Diseases (ICD) codes E819C (motor-cycle drivers) and E819D (motor-cycle passengers) recorded in the Swedish Hospital Discharge Register (SHDR) between 1987 and 1994. MAIN OUTCOME MEASURES Injury distribution, medical consequences, mortality, survival, and incidence by age, sex and geographical area. RESULTS The number of people admitted to hospital after motor-cycle crashes decreased significantly during the period (from 1743 in 1987 to 1258 in 1994, p < 0.001). The most frequent injuries among drivers and passengers alike were fractures of the legs, arms, and vertebrae, followed by injuries to the head and brain. The in-hospital mortality was lower among drivers (n = 172, 2.2%) than among passengers (n = 31,3.3%). CONCLUSION The incidence of injuries after motor-cyclist crashes decreased during the study period. The most common victims were young men with fractures and brain injuries. Those at most risk of dying were older passengers.
Inflammatory Bowel Diseases | 2008
Mensur Dzabic; Lennart Boström; Afsar Rahbar
Background Appendicitis is a very common surgical diagnosis with unclear pathology. Human cytomegalovirus (HCMV) can modulate our immune system and has been associated with inflammatory bowel disease (IBD) and various other inflammatory diseases. Methods We investigated the association between HCMV and acute appendicitis in 14 immunocompetent patients. Tissue sections from 10 AIDS patients with verified HCMV infection were used as positive controls, and uninflamed intestinal tissue sections from 12 patients were used as negative controls. Results Cells double positive for HCMV early antigens and IL‐6/IL‐8 were observed in the appendices of 64.3% of appendicitis patients (9 of 14) by immunohistochemical analysis. HCMV late antigen was found in the appendices of 42.9% of the acute appendicitis patients (6 of 14). Latent HCMV appendix infection, as verified by in situ hybridization, as well as HCMV IgG, was observed in 78.6% of patients (11 of 14). The study samples from all 6 healthy appendices were negative for HCMV early and late antigens, although 50% (3 of 6) were HCMV IgG and HCMV DNA positive. Conclusions We have shown that HCMV infection of the appendix is associated with acute appendicitis (P = 0.002) and possibly with the severity of the disease. Our study identified HCMV as a pathogen to be sought for in the appendicitis patient group, possibly allowing further medical treatment of these patients.
European Journal of Surgery | 2003
Lennart Boström; Andreas Wladis; Bo Nilsson
OBJECTIVES To find out the incidence, extent of injury, medical consequences, and mortality rate of moped riders involved in crashes in Sweden. DESIGN Retrospective case study. SETTING The Swedish Hospital Discharge Register (SHDR). SUBJECTS 4716 moped riders, a total of 5857 admissions to Swedish hospitals from 1987-94. INTERVENTIONS Statistical analysis of the Register. MAIN OUTCOME MEASURES Incidence of injured moped riders in Sweden, mortality rate, types of injuries, and medical consequences. RESULTS From 1987 to 1994, Swedish hospitals admitted 4716 moped riders (5857 admissions) injured in crashes, which corresponds to a mean of 8.5 injured/100 000 population a year. Of these 3993 were male (85%) and 723 female (15%), with a median age of 16 years (range 3-93). Twenty-four percent of those admitted to hospital spent more than a week there. The annual number of injured moped riders did not change significantly during this period. The total number of deaths in hospital was 59 (1%). Among those who died in hospital, 32 (54%) had head injuries, 16 (27%) fractures, and 5 (9%) abdominal or thoracic injuries. CONCLUSION The number of injured moped riders in Sweden is low. Fractures of the extremities were most common, followed by injuries to the head and brain. The usual victim was a teenager or young man. Of the patients treated in hospital few died, most of whom were elderly men.