Petter Malmborg

Karolinska Institutet, Solna, Stockholm, Sweden

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Publications (10)33.65 Total impact

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    ABSTRACT: Some studies have suggested that childhood-onset inflammatory bowel disease (IBD) is characterized by extensive intestinal involvement and rapid progression to complications. Here, we report the presentation and progression of patients diagnosed with IBD during childhood in a population-based cohort from northern Stockholm County. Medical records for all 280 patients diagnosed in the period 1990-2007 with childhood-onset IBD in northern Stockholm County were followed until 2011 (median follow-up time, 8.8 yr). Disease phenotypes were classified according to the Paris pediatric IBD classification. Among the 74 patients with ulcerative colitis, 72% presented with pancolitis. Among the 200 patients with Crohn's disease (CD), 75% presented with colitis. Complicated disease behavior was observed in 18% of patients with CD by end of follow-up. Extension of the disease territory was observed in 22% of patients with ulcerative colitis and 15% of patients with CD. The cumulative risk of intra-abdominal surgery after 10 years was 8% (95% confidence interval, 4%-20%) for ulcerative colitis and 22% (95% confidence interval, 15%-28%) for patients with CD. Nonmucosal healing at 1 year was associated with a complicated disease course in patients with CD (hazard ratio = 14.56; 95% confidence interval, 1.79-118.68; P = 0.01). Patients with childhood-onset IBD were characterized by extensive colitis that was relatively stable over time and associated with a relatively low risk of complications and abdominal surgery. Our findings confirm the more extensive disease location in pediatric IBD but did not identify the proposed dynamic and aggressive nature of the childhood-onset phenotype. The association of nonmucosal healing with a complicated disease course suggests that endoscopy should guide treatment intensity in childhood-onset CD.
    Inflammatory Bowel Diseases 04/2015; 21(5). DOI:10.1097/MIB.0000000000000356 · 5.48 Impact Factor
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    ABSTRACT: OBJECTIVES:: A sharp increase in paediatric (<16 years) inflammatory bowel disease (IBD) incidence was observed in northern Stockholm County in Sweden 1990-2001. The increasing incidence was primarily explained by a rising incidence of Crohn's disease (CD). Here we present an update on the trends in incidence of paediatric IBD 2002-2007. METHOD:: Medical records of all children diagnosed with suspected IBD in northern Stockholm County 2002-2007 were scrutinized using defined diagnostic criteria. Disease extension, localisation and behaviour at diagnosis were classified within the framework of the Paris classification. RESULT:: A total of 133 children were diagnosed with IBD 2002-2007 corresponding to a sex and age standardized incidence (per 10 person-years) for paediatric IBD of 12.8 (95% CI 10.8-15.2). The standardized incidence was 9.2 (95% CI 7.5-11.2) for CD and 2.8 (95% CI 1.9-4.0) for ulcerative colitis (UC). A significant increasing incidence of UC (p < 0.05) was observed during the study period. No temporal trend was observed for the incidence of CD. CONCLUSION:: The incidence rate of paediatric IBD in northern Stockholm was significantly higher in 2002-2007 than that observed in our earlier study covering 1990-2001. The former sharp increase in incidence of paediatric CD seems however to have levelled out although at a higher rate than reported from most other regions in the world. Although CD was still predominant, the observed increase in incidence of UC during the study period is notable.
    Journal of pediatric gastroenterology and nutrition 03/2013; 57(1). DOI:10.1097/MPG.0b013e31828f21b4 · 2.87 Impact Factor
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    ABSTRACT: Combined immunosuppression by immunomodulators and biological therapy has become standard in the medical management of moderate-to-severe inflammatory bowel disease (IBD) because of clearly demonstrated efficacy. Clinical studies, registries, and case reports warn of the increased risk of infections, particularly opportunistic infections; however, already in the steroid monotherapy era, patients are at risk because it is accepted that a patient should be considered immunosuppressed when receiving a daily dose of 20 mg of prednisone for 2 weeks. Prescriptions increasingly involve azathioprine, methotrexate, and various biological agents. The TREAT registry evaluated safety in >6000 adult patients, half of them treated with infliximab (IFX) for about 1.9 years. IFX-treated patients had an increased risk of infections and this was associated with disease severity and concomitant prednisone use. The REACH study, evaluating the efficacy of IFX in children with moderate-to-severe Crohn disease, refractory to immunomodulatory treatment, reports serious infections as the major adverse events and their frequency is higher with shorter treatment intervals. The combination of immunosuppressive medications is a risk factor for opportunistic infections. Exhaustive guidelines on prophylaxis, diagnosis, and management of opportunistic infections in adult patients with IBD have been published by a European Crohn's and Colitis Organization working group, including clear evidence-based statements. We have reviewed the literature on infections in pediatric IBD as well as the European Crohn's and Colitis Organization guidelines to present a commentary on infection prophylaxis for the pediatric age group.
    Journal of pediatric gastroenterology and nutrition 06/2012; 54(6):830-7. DOI:10.1097/MPG.0b013e31824d1438 · 2.87 Impact Factor
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    ABSTRACT: Crohn's disease (CD) could involve an inappropriate immune response against normal bowel flora. Disrupted or atypical patterns of microbial bowel colonization may impair development of homeostasis between gut flora and the immune system. Perinatal microbial exposures may be particularly important in stimulating intestinal immune recognition. As birth by cesarean section is thought to represent an atypical pattern of early bowel colonization, we examined its association with pediatric CD. Some 1536 patients diagnosed with pediatric CD and 15,439 controls matched by delivery unit, week of birth, sex, and born between 1973 and 2006 were identified through Swedish registers. The association of birth by cesarean section with pediatric CD was examined using conditional logistic regression, with stratification by sex and adjustment for parental socioeconomic index and maternal infections during pregnancy. Birth by cesarean section is associated with a modestly increased risk for pediatric CD among boys (odds ratio [OR] = 1.25, 95% confidence interval [CI] 1.01-1.54) but not girls, (OR = 0.99, 95% CI 0.76-1.29) and elective cesarean section is associated with a modest increased risk for the entire population (OR = 1.36, 95% CI 1.02-1.80). This study does not suggest that the delivery procedure should be altered, but the findings may be of etiological significance in CD, indicating a potential role for perinatal exposures associated with delivery mode. Although the sex difference may have arisen by chance, the modestly increased CD risk for boys delivered by cesarean section is consistent with sex-specific differences in susceptibility to some exposures.
    Inflammatory Bowel Diseases 01/2012; 18(4):703-8. DOI:10.1002/ibd.21741 · 5.48 Impact Factor
  • B Husberg, P Malmborg, K Strigård
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    ABSTRACT: Chronic anal fissures with painful defecation and bloodstained stools can be seen in children of all ages. Constipation may precede or appear in connection with the symptoms. Adult patients with anal fissures have been treated successfully with the injection of botulinum toxin into both the internal and external sphincter. The effect of botulinum toxin is reversible and lasts for 3-4 months. This pilot study attempted to examine whether botulinum toxin is also effective in paediatric cases of anal fissure, a treatment which not yet has been reported in the literature. Six boys and seven girls aged 1-10 years were treated with botulinum toxin (Botox ((R))) during 2002-2005 due to chronic anal fissure. Conventional treatment with laxatives and local anaesthetics had been unsuccessful in all cases. The treatment was given to five children under 2 years of age in a dosage of 1.25 Ux2. Eight children over 2 years of age were given 2.5 Ux2. The injections were given in the external sphincter on both sides of the fissure using EMG-stimulation for guidance and were performed under light anaesthetics (Diprivan ((R))). Follow-up was conducted at 1 and 3 months after treatment. Within one week, 11 of the children were free from pain and blood stained stools, according to their parent's observations. One 10-year old patient initially showed some improvement but soon experienced a recurrence. After another injection with a higher dosage 2 months later, the fissure healed. One 4-year old patient did not show any signs of improvement. The laxatives, which had been withdrawn after the injection treatment, were then reinstated. At the 3 month post-treatment examination the patient was finally symptom-free with no signs of a fissure. There were no negative side-effects detected in any of the cases. Seven recurrences were noted in 6 of the patients after 3-30 months, often in connection with an episode of constipation. Repeat injections were offered and accepted by four of these patients, once more producing good immediate results. Treatment with botulinum toxin in the external sphincter produces a quick and effective alleviation of pain with healing of chronic anal fissures in children. The treatment is not considered to carry any risks but requires light anaesthesia. Recurrences are common after the pharmacological effect has receded but can be cured with an additional injection.
    European Journal of Pediatric Surgery 09/2009; 19(5):290-2. DOI:10.1055/s-0029-1231052 · 0.98 Impact Factor
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    ABSTRACT: The purpose of the study was to collect data on granulocyte-monocyte adsorptive apheresis (GMA) for the treatment of corticosteroid-dependent (SD) or corticosteroid-resistant (SR) inflammatory bowel disease (IBD) in children from 3 Nordic countries to evaluate its efficacy and safety and to assess practical issues. Retrospective data on 37 children treated with GMA were collected. In all, 22 children had ulcerative colitis (UC), 13 Crohn's disease (CD), and 2 had indeterminate colitis (IC). Their mean age was 13.2 years, range 5-17 years, and mean duration of disease was 2.4 years, range 1 month to 6 years. Indication for treatment in the UC group was SD in 11 cases, SR in 6 cases, and other reasons in 5 cases. The corresponding numbers in the CD group were SD in 8 cases, SR in 2 cases, and other reasons in 3 cases. In the IC group, 1 had SD and 1 was refractory to steroids, azathioprine, and infliximab. Efficacy was evaluated by severity indices: the Pediatric Ulcerative Colitis Activity Index (PUCAI) and the Pediatric Crohn's Disease Activity Index (PCDAI) and tapering of corticosteroids. PUCAI and PCDAI decreased significantly in both groups after 3 months (P = 0.0007, P = 0.025). The dosage of corticosteroid was significantly reduced in the UC group by the end of GMA (P = 0.004) and this response continued after 3 months. Relapse was seen in 2 patients with UC and 3 patients with CD after 3 months follow-up. GMA seems to be an effective and safe treatment in 81% of the SD or SR pediatric IBD patients, especially in those with UC.
    Inflammatory Bowel Diseases 01/2009; 15(7):1049-54. DOI:10.1002/ibd.20859 · 5.48 Impact Factor
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    ABSTRACT: An inappropriate immune response to normal bowel flora is implicated in the etiology of Crohn's disease. Tolerance to bowel flora develops in infancy, so factors disrupting normal patterns of bowel colonization may increase the risk of Crohn's disease. The aim of this study was to test the hypothesis that antibiotic therapy between birth and age 5 years may disrupt the pattern of bowel colonization and increase the risk of Crohn's disease. Some 1098 patients with Crohn's disease and 6550 controls matched by delivery unit, year of birth, sex, and born between 1973 and 1997 were identified through the Swedish population registers. Seven inpatient diagnoses between birth and age 5 years associated with antibiotic therapy were identified by prospectively recorded data. Of the seven diagnoses, only pneumonia and otitis media were sufficiently common for use in the analyses. Pneumonia and otitis media were not independent of each other in their association with Crohn's disease and the more important association was with pneumonia. Pneumonia by age 5 years was statistically significantly associated with both pediatric- and adult Crohn's disease, with odds ratios (and 95% CI) of 2.74 (1.04-7.21) and 4.94 (1.83-13.23), respectively. Pneumonia after age 5 years was not statistically significantly associated with Crohn's disease. Pneumonia prior to age 5 years, but not later, was associated with subsequent Crohn's disease and this may represent either susceptibility or causation. The results are consistent with early exposures influencing immune function, such as through disruption of bowel colonization, and thus increasing the risk of Crohn's disease.
    Scandinavian Journal of Gastroenterology 09/2008; 43(8):961-6. DOI:10.1080/00365520801971736 · 2.33 Impact Factor
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    ABSTRACT: The risk of thromboembolism is increased in inflammatory bowel disease and its symptoms may be overlooked. Furthermore, its treatment can be complex and is not without complications. We describe a case of an adolescent boy who developed a cerebral sinus venous thrombosis during a relapse of his ulcerative colitis and who, while on treatment with heparin, developed heparin-induced thrombocytopenia (HIT). The treatment was then switched to fondaparinux, a synthetic and selective inhibitor of activated factor X.
    World Journal of Gastroenterology 08/2008; 14(28):4576-9. · 2.43 Impact Factor
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    ABSTRACT: The authors have previously described an association between cytomegalovirus (CMV) infection and intrahepatic and extrahepatic forms of neonatal cholestasis. Pediatric use of the antiviral drug ganciclovir to treat patients with CMV infection has increased. In this study, infants with CMV infection and cholestasis were treated with ganciclovir. Six infants with cholestasis (age, 3-16 weeks) and with signs of ongoing CMV infection were treated with intravenous ganciclovir for 3 to 7 weeks and observed for 4 to 31 months after treatment. Two patients had biliary atresia, one had suspected septo-optic dysplasia and three had no obvious cause for intrahepatic cholestasis other than ongoing CMV infection. Four patients, including one with biliary atresia, responded to the treatment, whereas two patients, including the one with septo-optic dysplasia did not. The latter patient had episodes of symptomatic hypoglycemia during the treatment, which was subsequently stopped. Liver function at the end of follow-up was good in four patients, intermediate in one, and poor in one. Ganciclovir treatment may be beneficial in infants with CMV-associated intrahepatic cholestasis, but controlled studies are needed. Because of the possible side effect of hypoglycemia, infants with cholestasis who have increased risk for such episodes should not be treated.
    Journal of Pediatric Gastroenterology and Nutrition 03/2002; 34(2):154-7. DOI:10.1097/00005176-200202000-00009 · 2.87 Impact Factor
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    Thomas H. Casswall, Petter Malmborg, Antal Nemeth
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    ABSTRACT: Background: The authors have previously described an asso- ciation between cytomegalovirus (CMV) infection and intrahe- patic and extrahepatic forms of neonatal cholestasis. Pediatric use of the antiviral drug ganciclovir to treat patients with CMV infection has increased. In this study, infants with CMV infec- tion and cholestasis were treated with ganciclovir. Methods: Six infants with cholestasis (age, 3-16 weeks) and with signs of ongoing CMV infection were treated with intra- venous ganciclovir for 3 to 7 weeks and observed for 4 to 31 months after treatment. Two patients had biliary atresia, one had suspected septo-optic dysplasia and three had no obvious cause for intrahepatic cholestasis other than ongoing CMV in- fection. Results: Four patients, including one with biliary atresia, re- sponded to the treatment, whereas two patients, including the one with septo-optic dysplasia did not. The latter patient had episodes of symptomatic hypoglycemia during the treatment, which was subsequently stopped. Liver function at the end of follow-up was good in four patients, intermediate in one, and poor in one. Conclusion: Ganciclovir treatment may be beneficial in infants with CMV-associated intrahepatic cholestasis, but controlled studies are needed. Because of the possible side effect of hy- poglycemia, infants with cholestasis who have increased risk for such episodes should not be treated. JPGN 34:154-157,
    Journal of Pediatric Gastroenterology and Nutrition 01/2002; 35(3). DOI:10.1097/00005176-200209000-00036 · 2.87 Impact Factor