Abstract: Women with inherited bleeding disorders present a wide spectrum of clinical symptoms that vary from mild or moderate bleeding tendency to severe episodes. Monthly haemostatic changes affect these women during menstruation and ovulation. These events may be associated with significant bleeding and pain leading to the limitations in conducting daily activities and adverse effect on quality of life. Likewise, pregnancy and delivery are critical times for affected women. During pregnancy, they may be at greater risk of miscarriage and bleeding complications. In particular, recurrent miscarriage was observed in women with type 3 von Willebrand disease, afibrinogenaemia and severe factor XIII deficiency, and an optimal therapeutic plan is required during their pregnancy. Precautions must be taken at delivery in these women, since they could be at risk of bleeding. The lack of adequate information makes it very difficult to prepare evidence-based guidelines for the prevention of bleedings in affected women and their treatment. A multidisciplinary team of obstetricians, haematologists and paediatricians is required with a good knowledge of these disorders and an awareness of the potential maternal neonatal complications.
Abstract: Different rates of inhibitor development after either plasma-derived (pdFVIII) or recombinant (rFVIII) FVIII have been suggested. However, conflicting results are reported in the literature.
Abstract: Campomelic dysplasia is a malformation syndrome with multiple symptoms including characteristic shortness and bowing of the long bones (campomelia). CD, often lethal due to airway malformations, is caused by heterozygous mutations in SOX9, an SRY-related gene regulating testis and chondrocyte development including expression of many cartilage genes such as type II collagen. Male to female sex reversal occurs in the majority of affected individuals with an XY karyotype. A mild form without campomelia exists, in which sex-reversal may be also absent. We report here two novel SOX9 missense mutations in a male (c.495C>G; p.His165Gln) and a female (c.337A>G; p.Met113Val) within the DNA-binding domain leading to non-lethal acampomelic CD. Functional analyses of mutant proteins demonstrate residual DNA-binding and transactivation of SOX9-regulated genes. Combining our data and reports from the literature we postulate a genotype-phenotype correlation: SOX9 mutations allowing for residual function lead to a mild form of CD in which campomelia and sex reversal may be absent.
Abstract: Among risk factors for developing thromboembolism (VTE) in children with acute lymphoblastic leukemia were Escherichia coli asparaginase, concomitant steroid use, presence of central venous lines, and thrombophilic abnormalities. Developing a predictive model for determining children at increased risk would be beneficial in targeting interventional studies to high-risk groups (HRGs). Predictive variables were incorporated into a risk assessment model, which was evaluated in 456 children and then validated in 339 patients. VTE risk by score was no greater than 2.5 for low-risk group (LRG) and greater than 2.5 for HRG. VTE rates at 3.5 months (validation cohorts) were 2.5% in LRG and 64.7% in HRG. In multivariate analysis adjusted for age, duration of asparaginase administration, enoxaparin prophylaxis, and T-immunophenotype, the HRG was significantly associated with VTE compared with the LRG (hazard/95% confidence interval [CI], 8.22/1.85-36.53). Model specificity was 96.2% and sensitivity was 63.2%. As secondary objective we investigated the use of enoxaparin for VTE prophylaxis in the HRG. HRG patients without enoxaparin prophylaxis showed a significantly reduced thrombosis-free survival compared with children on low-molecular-weight heparin (LMWH). On the basis of the high specificity, the model may identify children with leukemia at risk of VTE. LMWH may help prevent VTE in the HRG; this warrants assessment in larger cooperative clinical trials.
Abstract: SUMMARY: The most problematic complication of haemophilia A treatment is the development of inhibitors to FVIII. The highest risk of developing inhibitors is during the first 20 exposure days (EDs). If the patient can be brought through this high risk period without inhibitor development, the subsequent risk is low. Therefore, as a pilot project, we developed a prophylaxis regimen for the first 20-50 EDs specifically designed to induce tolerance to the administered FVIII and to minimize inhibitor development by avoiding immunological danger signals. Twenty-six consecutive previously untreated patients (PUPs) with severe haemophilia A were treated with the new prophylaxis regimen and the incidence of inhibitor development in this group was compared with that in a historical control group of 30 consecutive PUPs treated with a standard joint protection prophylaxis regimen (40-50 IU kg(-1), three times a week). There were no significant differences between the study and control groups in patient-related inhibitor risk factors such as ethnicity (all Caucasian), severity of haemophilia (all <1% FVIII), severity of FVIII gene mutation (P < 0.0006) nor in some treatment-related factors such as product type, age at first exposure, vaccination regimen or the need for surgery. 14 of 30 subjects given standard prophylaxis but only one of the 26 subjects given the new regimen developed an inhibitor (P = 0.0003, odds ratio 0.048, 95% CI: 0.001-0.372). Our results indicate that minimizing danger signals during the first 20 EDs with FVIII may reduce the risk of inhibitor formation. These results should be confirmed in a larger prospective clinical study.
Abstract: Bleeding after ear-nose-and throat surgery in children is a serious complication. With the help of the German Surveillance Unit for Rare Paediatric Disorders (Erhebungseinheit für seltene pädiatrische Erkrankungen in Deutschland; ESPED) a two year survey was performed to record the incidence, severity, reasons and treatment of haemorrhages. During the study period, 1069 bleeds were reported from 720 paediatric hospitals and departments of otorhinolaryngology after adenoidectomy and tonsillectomy. 713 reports could be analyzed. Two deaths occurred after adenoidectomy. Although laboratory screening was performed in more than 70% of all cases, bleeding complications were neither foreseeable nor preventable. Inherited coagulopathies were rare and in most cases not detected, neither by laboratory screening nor by taking a history. Since preoperative measures cannot help much to improve the situation, all efforts have to be taken to improve the postoperative period, especially since more than 20% of the hemorrhages occurred during weekends. Guidelines on postoperative care and behaviour should therefore be implemented and parents and patients must be informed on bleeding risks and on what to do in case of emergency. If bleeding occurs, extensive coagulation testing is mandatory.
Abstract: In Germany, preoperative coagulation tests are commonly used, based on the belief that these tests should identify patients with an increased bleeding risk. However, published evidence does not longer support this approach for both traditional screening tests and novel techniques of global assessment of haemostasis. Unselected screening yields many false positive results and detects irrelevant disorders. It leads to postponement of surgery, anxiety in parents and patients, and is not cost effective. Even worse, it does not reliably detect relevant bleeding disorders such as the most common coagulopathy, von Willebrand disease. The bleeding history of patients and their relatives is a more effective tool to detect patients at risk. According to international guidelines and a joint statement of different German medical societies, a standardized questionnaire should be mandatory in preoperative screening. A diagnostic pathway should be employed to identify patients in whom specific tests are helpful. Because neither laboratory tests nor questionnaires can infallibly predict or exclude perioperative bleeding, guidelines for the management of these unexpected situations have to be established.
Abstract: Every year in Germany nearly 3000 cases of child abuse were reported. When children are presented at emergency units with suspicious injuries and bruises a detailed documentation an evaluation is necessary after emergency treatment. As differential diagnosis inherited or acquired bleeding disorders should be excluded. In addition to a detailed evaluation of personal and family history and a physical evaluation different coagulation test to exclude defects of primary and secondary hemostasis should be performed. Clinician must know the limitations of these tests and keep in mind that an abnormal coagulation test does not exclude child abuse. Coagulation defects may be the consequence of child abuse and neglect or the two conditions may coexist.
Abstract: Since the early nineties it has been shown that low molecular weight heparin (LMWH) has significant advantages over unfractionated heparin and oral anticoagulants for both the treatment and the prevention of thrombosis, not only in adults, but also in children. The present review was based on an 'EMBASE', 'Medline' and 'PubMed' search including literature published in any language since 1980 on LMWH in neonates, infants and children. It included paediatric pharmacokinetic studies, the use of LMWH in children with venous thrombosis, LMWH administration in paediatric patients with ischaemic stroke, and its use in order to prevent symptomatic thromboembolism in children at risk. An increasing rate of off-label use of LMWH in children has been reported, showing that LMWHs offer important benefits to children with symptomatic thromboembolic events and poor venous access. Two well-conducted pharmacokinetic studies in this age group showed that neonates and younger infants require higher LMWH doses than older children to achieve the targeted anti-Xa levels, due to an increased extra vascular clearance. Recurrent symptomatic thromboses under LMWH occur in approximately 4% of children treated for venous thrombosis, and in 7% of children treated for stroke; major bleed was documented in 3% of children with therapeutic target LMWH anti-Xa levels, whereas minor bleeding was reported in approximately 23% of children receiving either therapeutic or prophylactic doses, respectively. Further randomized controlled trials are recommended to evaluate the optimum duration and application for different LMWH indications in children.
Abstract: The development of inhibitors is one of the most important complications of replacement therapy in haemophilia, affecting mortality and morbidity. Inhibitor development is based on complex immunological factors. Cytokines and their receptors, T-cell receptors, and the Major Histocompatibility Complex may play important roles in the development of inhibitors. Earlier studies showed non significant associations between HLA class and inhibitor development. Later studies found an increased risk of inhibitor development if there was a combination between certain factor VIII mutations and HLA antigens. We performed HLA typing in 50 patients with haemophilia A in an effort to find associations with inhibitor development. RESULTS: 25 patients had developed an inhibitor (11 low titre, 14 high titre), and 25 never had. In logistic regression analysis, HLA-A 34, DRB1 0405, DRB1 1301 seemed to be involved in inhibitor development and HLA-A 30, B 13, B15, B 57, Cw 12, DQB1 0303, DPB1 0201 protection against inhibitor development. In our patients, the HLA-associations with inhibitor development were different from those in previous publications.
Abstract: Patients with severe haemophilia A (HA) can either be treated by regular FVIII infusions twice or three times per week (prophylaxis), or only in case of bleeding episodes (on-demand). Whereas prophylaxis reduces the number of bleeding episodes and may therefore prevent the development of haemophilic arthropathy, there is still a lot of controversy surrounding recommendations on age and dose at start of prophylactic regimens. The present database study was performed to investigate the role of primary versus secondary prophylaxis in HA children. The outcome variable was imaging-proven haemophilic joint damage. Forty-two children were initially treated with primary prophylaxis following the first bleeding episode, and were frequency-matched (year of birth, catchment area) to 67 patients receiving "on-demand" therapy with an early switch to "secondary prophylaxis". In multivariate analysis adjusted for the HA mutation type and the presence or absence of thrombophilia, the Pettersson score investigated at a median age of 12.5 years in joints with at least one documented bleeding episode was not significantly different between the two patient groups (p = 0.944), and no statistically significant differences were found in patients with target joints (p = 0.3), nor in children in whom synovitis had occurred (p = 0.77). No conclusion can be drawn from the data presented herein whether primary prophylaxis or an early start of secondary prophylaxis is superior with respect to joint outcome in children with severe HA.
Abstract: The introduction of new needleless devices as demanded by the US Department of Labor Occupational Safety and Health Administration (OSHA) has caused problems with the reconstitution of antihaemophilic factor in emergency situations. Our aim therefore was to evaluate the feasibility of a needleless device for reconstitution of antihaemophilic factor for non-haemophilia experts and to define evidence of the need for coaching these physicians via providing two additional photographs illustrating the two key points of the factor reconstitution process. Twenty-eight physicians of a tertiary care university children's hospital were randomized into two groups, either with no further explanation of the reconstitution device or with two additional photographs, showing the two key steps of the procedure. Reconstitution of dummy-factor concentrate was video-taped and evaluated by a blinded helper. Main outcome measure was the successful reconstitution of dummy-factor concentrate and procedure failure respectively. Of the group without explanation of the reconstitution device, only two of 14 physicians were able to reconstitute the dummy-factor concentrate. Of the group receiving two photographs, nine of 14 completed the task successfully (P = 0.0068). The needleless device is not self explaining to non-haemophilia physicians involved in emergency services. Coaching via short to the point instructions as provided by simple visual educational material therefore is crucial to enable these physicians to resolve the expensive emergency drug quickly and correctly. Companies concerned with the production of any devices to dissolve drugs, especially for treatment of rare diseases as haemophilia, therefore should take measures to simplify therapy.
Abstract: The present multicenter cohort study of 107 pediatric PUPs was performed to determine whether the concomitant inheritance of the factor (F) V G1691A or the F II G20210A mutation influences the clinical expression of severe hemophilia A (HA). Carriers of the FV and FII mutations had a significantly lower annual bleeding frequency (ABF) than non-carriers (p=0.012). Joint damage (Pettersson score) was significantly less severe in patients with thrombophilia (p=0.022). A protective effect of thrombophilic risk factors was shown for ABF (OR [CIs]: 0.7[0.5-0.9]; p=0.02) and the severity of the hemophilic arthropathy (OR [CIs]: 0.06[0.01-0.3]; p=0.0009).
Abstract: BACKGROUND: The relative importance of previous diagnosis and hereditary prothrombotic risk factors for cerebral venous thrombosis (CVT) in children in determining risk of a second cerebral or systemic venous thrombosis (VT), compared with other clinical, neuroimaging, and treatment variables, is unknown. METHODS: We followed up the survivors of 396 consecutively enrolled patients with CVT, aged newborn to 18 years (median 5.2 years) for a median of 36 months (maximum 85 months). In accordance with international treatment guidelines, 250 children (65%) received acute anticoagulation with unfractionated heparin or low-molecular weight heparin, followed by secondary anticoagulation prophylaxis with low-molecular weight heparin or warfarin in 165 (43%). RESULTS: Of 396 children enrolled, 12 died immediately and 22 (6%) had recurrent VT (13 cerebral; 3%) at a median of 6 months (range 0.1-85). Repeat venous imaging was available in 266 children. Recurrent VT only occurred in children whose first CVT was diagnosed after age 2 years; the underlying medical condition had no effect. In Cox regression analyses, non-administration of anticoagulant before relapse (hazard ratio [HR] 11.2 95% CI 3.4-37.0; p<0.0001), persistent occlusion on repeat venous imaging (4.1, 1.1-14.8; p=0.032), and heterozygosity for the G20210A mutation in factor II (4.3, 1.1-16.2; p=0.034) were independently associated with recurrent VT. Among patients who had recurrent VT, 70% (15) occurred within the 6 months after onset. CONCLUSION: Age at CVT onset, non-administration of anticoagulation, persistent venous occlusion, and presence of G20210A mutation in factor II predict recurrent VT in children. Secondary prophylactic anticoagulation should be given on a patient-to-patient basis in children with newly identified CVT and at high risk of recurrent VT. Factors that affect recanalisation need further research.
Abstract: Although the concept of continuous infusion (CI) of factor concentrates is well known, prospective paediatric data are rare. We present a prospective open-labelled non-randomized study focusing on safety, efficacy and factor VIII (FVIII) usage compared with bolus injections (BI) in children. In 43 consecutive patients (0.5-17 years; median: 9.6) undergoing different operations, CI was started with an initial FVIII-bolus of 70 IU kg(-1) bodyweight, followed by a median infusion rate of 4.4 IU kg(-1) h(-1) (range: 2.8-9.5) dose adjusted for daily FVIII levels (target: 60-80%). No direct serious adverse events occurred; however, two out of 43 patients, both from the group of four patients with less than 20 exposure days (ED) before starting CI, developed a high-responding inhibitor. Two CI patients showed mild thrombophlebitis or rash. Infusion rates needed to achieve adequate FVIII levels were highly predictable and could be reduced because of decreasing FVIII clearance. Bleeding, requiring additional boli, was observed in eight out of 43 patients. Therapy duration and factor usage of CI were influenced by the procedure, but not by the product used or thrombophilia. Twelve of these CI patients were compared with 12 contemporary consecutive age- and procedure-matched BI patients. Compared with BI patients, CI patients saved 30% FVIII (812.9 vs. 563.2 IU kg(-1), P < 0.006). We conclude that CI forms a safe and effective method for perioperative care in children and reduces factor usage. Because of the unknown risk of inhibitor development, we will use CI only in patients beyond 20 ED.
Abstract: In this open label pilot safety study 80 children over 3 months old with deep venous thrombosis were treated with enoxaparin with a target 4 h anti-factor Xa activity between 0.5-0.8 IU/mL. The children were stratified to receive once daily or twice daily doses. The study end-points were post-thrombotic syndrome, re-thrombosis, bleeding, and therapy-related death. The median duration of treatment was 5 months and the median follow-up was 24 months. No significant differences were found between the two groups of patients. No bleeding or therapy-related deaths occurred. These safety and efficacy data may serve as a basis to initiate an international multicenter study on enoxaparin treatment.
Abstract: Immune-mediated heparin-induced thrombocytopenia (HIT) is an uncommon but serious complication of therapy with heparins. It affects all ages and requires replacement of the causative anticoagulant. However, information on alternative antithrombotic use in children with HIT is limited. This paper reviews 27 published and 7 unpublished case reports of children aged 2 weeks to 17 years treated with danaparoid. Thirty-three suffered from HIT or suspected HIT, and 1 child without HIT had a high bleeding risk. All children had severe underlying problems increasing their thrombotic and/or bleeding risk. HIT diagnosis was confirmed serologically or clinically in 26 cases (78.8%). Danaparoid regimens were similar to those used in adults, but in general, younger children needed higher daily doses of danaparoid to achieve the same target plasma anti-Xa levels than teenagers or adults. Of those with a known outcome 28/33 children (84.8%) survived, 7 having suffered from a serious adverse event. Five deaths occurred including 1 thrombotic and 2 major bleeds. Three of the in total 4 major bleeding events occurred in children undergoing surgery with cardiopulmonary bypass. We conclude that despite the reported adverse events danaparoid can be used as an alternative antithrombotic for children who are intolerant of the heparins, except in cases requiring cardiopulmonary bypass surgery.
Abstract: The incidence of prematurity in Germany is about 10% and premature infants with haemophilia A (OMIM 306700) are in fact very rare. We report two new cases, one born in the 28th gestational week, weighing 1200 g with a factor VIII (FVIII) level of 0.03 IU/ml treated with bolus injections of plasma derived FVIII concentrate (pdFVIII), and one born at week 30, weighing only 710 g with a factor level of <0.01 IU/ml and treated with recombinant FVIII concentrate (rFVIII). Recovery of FVIII was 96% in case 1 and 120% in case 2, FVIII half-life was 6 h and 8 h, respectively. During FVIII substitution, neither bleeding, thrombosis nor inhibitor development were noted in both infants. Conclusion:Immediate and frequent factor VIII substitution appears to be safe and effective for prophylaxis and treatment in premature haemophilic neonates.
Abstract: Intracellular detection of cytokines via fluorescent antibody staining and flow cytometry has quickly become a standard method in experimental immunology. However, in pediatrics most studies have been hampered by the exclusion of healthy control individuals or have been skewed by neglecting to observe age-dependent differences in cytokine production. We therefore intended to establish normal values for different age groups and to describe the age-dependent development of cytokine profiles. Whole blood from 46 healthy children and 33 adults was analyzed by flow cytometry after stimulation with PMA, ionomycin and Mmonensin, and staining with anti-cytokine and surface antibodies. In the pediatric population, we found a significant positive correlation between age and intracellular cytokine levels of IFN-gamma, IL-2, IL-4 and TNF-alpha in CD4+ cells, as well as for IFN-gamma and TNF-alpha in CD8+ cells. In adulthood, no such striking trend could be detected, but significant correlation was found for IL-10 in CD4+ cells and IFN-gamma in CD8+ cells as well as for TNF-alpha in both cell subgroups. We present here the first systematic analysis of intracellular cytokine production in normal, healthy children between the ages of 0 to 18 years compared to results in adults. These data may provide a reference basis for the study of cytokine secretion patterns, and they also demonstrate a significant maturation of the T-cell cytokine production capacity from birth to adulthood.
Abstract: Adenosine is a potent anti-inflammatory mediator. Through elevation of endogenous adenosine concentrations the adenosine kinase inhibitor GP515 might serve to down-regulate local inflammatory responses. In the present study we investigated the effect of systemic GP515 in the nonacute model of dextran sulfate sodium (DSS)-induced colitis. The clinical score, colon length, histologic score, colon cytokine production, and spleen weight from mice with DSS-induced colitis (3.5% DSS in drinking water for 11 days) receiving GP515 treatment were determined and compared with untreated control mice. Splenocytes were analyzed for phenotype, interferon-gamma (IFNgamma) production, and CD69 expression. First, GP515 treatment resulted in a significant improvement of clinical score (weight loss, stool consistency, and bleeding) and of histologic score. Second, colon shortening, an indirect parameter for the degree of inflammation, was decreased, consistent with a decreased IFNgamma concentration in the colonic tissue. Third, spleen weight was reduced in GP515-treated DSS mice. And fourth, IFNgamma synthesis and CD69 expression, as a marker for early cell activation, of ex vivo-stimulated splenocytes were suppressed in the GP515-treated DSS mice. These studies show that GP515 is effective in the therapy of DSS-induced colitis. One potential mechanism of action is the suppression of IFNgamma synthesis and CD69 expression. Adenosine kinase inhibition forms a pharmacologic target that should be further investigated for chronic inflammatory bowel disease.
Abstract: The specific type IV phosphodiesterase inhibitor rolipram is a potent suppressor of tumor necrosis factor-alpha (TNF) synthesis. We examined the efficacy of rolipram for the prevention and treatment of experimental colitis. To induce colitis, BALB/c mice received 5% dextran sulfate sodium in their drinking water continuously for up to 11 days. Colitis was quantified by a clinical activity score assessing weight loss, stool consistency, and rectal bleeding (range from 0 to 4); by colon length; by a semiquantitative histologic score (range from 0 to 6); and by detecting TNF concentration in colonic tissue by enzyme-linked immunosorbent assay. In a first protocol, rolipram (10 mg/kg b.wt./day i.p.) was started on the same day as dextran sulfate sodium. Rolipram reduced the clinical activity of colitis (score 1.1 +/- 0.3) compared with mice that did not receive rolipram (2.4 +/- 0.4; P =.041). Rolipram also partially reversed the reduction of colon length (without rolipram, 12.4 +/- 0. 3 cm; with rolipram, 15.4 +/- 0.7 cm; P =.004) and improved the histologic score (1.5 +/- 0.6 in rolipram-treated mice versus 4.6 +/- 0.5; P =.020). Rolipram suppressed colonic tissue TNF concentrations. The beneficial effect of rolipram was confirmed in a second protocol in which dextran sulfate sodium exposure was discontinued on day 7 and rolipram was administered from day 8 through day 15. These three series of experiments on a total of 153 mice documented the efficacy of rolipram in both the prevention and treatment of experimental colitis.
Abstract: Hypoxic pulmonary vasoconstriction is associated with but may not be sufficient for the development of high-altitude pulmonary oedema (HAPO). Hypoxia is known to induce an inflammatory response in immune cells and endothelial cells. It has been speculated that hypoxia-induced inflammatory cytokines at high altitude may contribute to the development of HAPO by causing capillary leakage in the lung. We were interested if such an inflammatory response, possibly involved in a later development of HAPO, is detectable at high altitude in individuals without HAPO. We examined the plasma levels of interleukin 6 (IL-6), interleukin 1 receptor antagonist (IL-1ra) and C-reactive protein (CRP) in two independent studies: study A, Jungfraujoch, Switzerland, three overnight stays at 3458 m, n=12; study B: Capanna Regina Margherita, Italy, 3 overnight stays at 3647 m and one overnight stay at 4559 m, n=10. In both studies, probands showed symptoms of acute mountain sickness but no signs of HAPO. At the Jungfraujoch, IL-6 increased from 0.1+/-0.03 pg/ml to 2. 0+/-0.5 pg/ml (day 2, P=0.03), IL-1ra from 101+/-21 to 284+/-73 pg/ml (day 2, P=0.01), and CRP from 1.0+/-0.4 to 5.8+/-1.5 micrograms/ml (day 4, P=0.01). At the Capanna Margherita, IL-6 increased from 0. 5+/-0.2 pg/ml to 2.0+/-0.8 pg/ml (P=0.02), IL-1ra from 118+/-25 to 213+/-28 pg/ml (P=0.02), and CRP from 0.4+/-0.03 to 3.5+/-1.1 micrograms/ml (P=0.03). IL-8 was below the detection limit of the ELISA (<25 pg/ml) in both studies. The increase of IL-6 and IL-1ra in response to high altitude was delayed and preceded the increase of CRP. We conclude that: (1) circulating IL-6, IL-1ra and CRP are upregulated in response to hypobaric hypoxic conditions at high altitude, and (2) the moderate systemic increase of these inflammatory markers may reflect considerable local inflammation. The existence and the kinetics of high altitude-induced cytokines found in this study support the hypothesis that inflammation is involved in the development of HAPO.
Abstract: BACKGROUND: Interleukin 1 (IL-1) and its physiological antagonist interleukin-1 receptor antagonist (IL-1 ra) play a crucial role in the pathogenesis of inflammatory bowel disease. Polymorphisms in the genes coding for these cytokines, the restriction enzyme TaqI polymorphism for IL-1 beta and the variable number of tandem repeats (VNTR) polymorphism for IL-1 ra, have been shown to influence cytokine synthesis in vitro. Recently, an association has been described for distinct allele combinations of these two polymorphisms in patients with ulcerative colitis and with Crohn's disease but not in healthy control subjects. METHODS: We studied 56 patients with ulcerative colitis, 64 patients with Crohn's disease and 196 healthy control subjects. All were unrelated Caucasians of European ancestry. After polymerase chain reaction (PCR) the amplification products were analysed on agarose gels. For the IL-1 beta polymorphism the PCR product was additionally digested using the restriction enzyme TaqI. RESULTS: The allele and genotype frequencies as well as the carriage rates of the IL-1 beta TaqI polymorphism in healthy control subjects were in agreement with previous findings in other populations. Allele and genotype frequencies of the IL-1 beta polymorphism were not different in inflammatory bowel disease patients compared with healthy control subjects. Comparing allele combinations of both polymorphisms no association could be identified either within healthy control subjects or in the groups of patients with ulcerative colitis or Crohn's disease. CONCLUSION: Thus, we could not confirm the results of a previous study reporting an association between the IL-1ra and IL-1 beta gene polymorphisms in patients with inflammatory bowel disease.
