The diagnosis and management of CMV colitis in IBD patients shows high practice variation: a national survey among gastroenterologists.

BACKGROUND: Clinical guidelines on cytomegalovirus (CMV) colitis in inflammatory bowel disease (IBD) are hampered by the low quality of evidence. In this study, we aim to explore the attitude and management of CMV colitis in IBD among gastroenterologists. METHODS: A web-based survey was distributed to adult and pediatric gastroenterologists and trainees in academic and general hospitals in the Netherlands. The survey comprised data collection on respondents' demographics, attitudes towards the importance of CMV infection in IBD on a visual analogue scale (from 0 to 100), and diagnostic and therapeutic strategies. RESULTS: A total of 73/131 invited respondents from 32 hospitals completed the survey (response rate of 56%). The importance of CMV infection was scored at a median 74/100. Respondents indicated CMV testing as appropriate in the clinical setting of steroid-refractory colitis (69% of respondents), hospitalized patients with active colitis (64%), immunomodulator or biological refractory colitis (55%) and active colitis irrespective of medication use (14%). CMV diagnostics include histology of colonic biopsies (88% of respondents), tissue CMV PCR (43%), serum CMV PCR (60%), CMV serology (25%) and fecal CMV PCR (4%). 82% of respondents start antiviral therapy after a positive CMV test on colonic biopsies (histology or PCR). CONCLUSIONS: Most Dutch gastroenterologists acknowledge the importance of CMV colitis in IBD. Strategies vary greatly with regard to the indication for testing and diagnostic method, as well as indication for the start of antiviral therapy. These findings underline the need for pragmatic clinical studies on different management strategies, in order to reduce practice variation and improve the quality of care. Summary of the established knowledge on this subject:The clinical significance of CMV-associated colitis in IBD remains a matter of debateRecommendations regarding CMV colitis in current international guidelines are based on low to moderate evidence levels and different diagnostic strategies are proposed What are the significant and/or new findings of this study?We show that there is a high practice variation of diagnosis and management of CMV colitis in IBD amongst adult and pediatric gastroenterologistsThis study underlined the need for pragmatic studies and guidelines on different management strategies including cut-off values to start therapy.

IL-10 signaling in dendritic cells controls IL-1ß-mediated IFNγ secretion by human CD4+ T cells: relevance to inflammatory bowel disease.

Uncontrolled interferon γ (IFNγ)-mediated T-cell responses to commensal microbiota are a driver of inflammatory bowel disease (IBD). Interleukin-10 (IL-10) is crucial for controlling these T-cell responses, but the precise mechanism of inhibition remains unclear. A better understanding of how IL-10 exerts its suppressive function may allow identification of individuals with suboptimal IL-10 function among the heterogeneous population of IBD patients. Using cells from patients with an IL10RA deficiency or STAT3 mutations, we demonstrate that IL-10 signaling in monocyte-derived dendritic cells (moDCs), but not T cells, is essential for controlling IFNγ-secreting CD4+ T cells. Deficiency in IL-10 signaling dramatically increased IL-1ß release by moDCs. IL-1ß boosted IFNγ secretion by CD4+ T cells either directly or indirectly by stimulating moDCs to secrete IL-12. As predicted a signature of IL-10 dysfunction was observed in a subgroup of pediatric IBD patients having higher IL-1ß expression in activated immune cells and macroscopically affected intestinal tissue. In agreement, reduced IL10RA expression was detected in peripheral blood mononuclear cells and a subgroup of pediatric IBD patients exhibited diminished IL-10 responsiveness. Our data unveil an important mechanism by which IL-10 controls IFNγ-secreting CD4+ T cells in humans and identifies IL-1ß as a potential classifier for a subgroup of IBD patients.

Clinical and endoscopic complications of Epstein-Barr virus in inflammatory bowel disease: an illustrative case series.

BACKGROUND AND AIM: Epstein-Barr virus (EBV) is a proposed trigger in the etiopathogenesis of inflammatory bowel disease (IBD) and is associated with lymphoproliferative diseases. Nevertheless, testing for EBV DNA in the intestinal mucosa and screening for EBV infection before initiation of a drug therapy are not routinely performed. The aim of this article is to increase awareness of the relevance of EBV infection in specific clinical situations. METHODS: In this short communication, we describe the disease course of three IBD patients with EBV infection, varying from EBV reactivation during disease flare up to a trigger of EBV-related mucocutaneous ulcer (EBV-MCU) and haemophagocytic lymphohistiocytosis (HLH). RESULTS: Our first patient was diagnosed with EBV reactivation-associated severe colitis and showed a rapid clinical improvement after induction therapy with infliximab and azathioprine. Without antiviral treatment, the patient remained in complete remission and no complications of EBV were seen. After diagnosing EBV-MCU in the second patient, immunosuppressive medication was discontinued and four infusions of rituximab resulted in a rapid clinical recovery and eventually complete response. After discontinuation of the immunosuppression in our last patient with haemophagocytic lymphohistiocytosis, treatment with a combination of corticosteroid and antiviral therapy resulted in a complete recovery over a time span of several weeks. CONCLUSION: EBV infection has a wide variety of potentially life-threatening clinical manifestations in IBD patients. Testing for EBV in case of a flare up and screening for EBV before the start of immunosuppressive therapy will create awareness for EBV-related symptoms or complications during follow-up.

Malignancy and mortality in paediatric-onset inflammatory bowel disease: a 3-year prospective, multinational study from the paediatric IBD Porto group of ESPGHAN.

BACKGROUND: Risk benefit strategies in managing inflammatory bowel diseases (IBD) are dependent upon understanding the risks of uncontrolled inflammation vs those of treatments. Malignancy and mortality in IBD have been associated with disease-related inflammation and immune suppression, but data are limited due to their rare occurrence. AIM: To identify and describe the most common causes of mortality, types of cancer and previous or current therapy among children and young adults with paediatric-onset IBD. METHODS: Information on paediatric-onset IBD patients diagnosed with malignancy or mortality was prospectively collected via a survey in 25 countries over a 42-month period. Patients were included if death or malignancy occurred after IBD diagnosis but before the age of 26 years. RESULTS: In total, 60 patients were identified including 43 malignancies and 26 fatal cases (9 due to cancer). Main causes of fatality were malignancies (n = 9), IBD or IBD-therapy related nonmalignant causes (n = 10; including 5 infections), and suicides (n = 3). Three cases, all fatal, of hepatosplenic T-cell lymphoma were identified, all were biologic-naïve but thiopurine-exposed. No other haematological malignancies were fatal. The 6 other fatal cancer cases included 3 colorectal adenocarcinomas and 3 cholangiocarcinomas (CCAs). Primary sclerosing cholangitis (PSC) was present in 5 (56%) fatal cancers (1 colorectal carcinoma, 3 CCAs and 1 hepatosplenic T-cell lymphoma). CONCLUSIONS: We report the largest number of paediatric-onset IBD patients with cancer and/or fatal outcomes to date. Malignancies followed by infections were the major causes of mortality. We identified PSC as a significant risk factor for cancer-associated mortality. Disease-related adenocarcinomas were a commoner cause of death than lymphomas.

Anti-Tumour Necrosis Factor Therapy for Paediatric Crohn's Disease: Improved Benefits Through Treatment Optimisation, Deeper Understanding of Its Risks, and Reduced Costs due to Biosimilar Availability.

Antibodies directed to tumour necrosis factor-α (TNF-α) are very effective in treating paediatric Crohn's disease (CD). Over the last few years, research has provided important new insights into how to optimise this treatment's effectiveness. Research on predictors for anti-TNF treatment responsiveness has revealed potential markers, but data on their accuracy in paediatric CD patients are lagging behind. Also, new evidence has become available on the safety profile of anti-TNF antibodies that suggests the assumed increased malignancy risk seen in patients on anti-TNF and thiopurine combination treatment may be linked more to thiopurine use and not to anti-TNF treatment. In addition, the early results of CT-P13, an infliximab biosimilar, in CD patients confirm the expected similarity with its originator. Thus, the effectiveness of anti-TNF antibody treatment is slowly improving, its malignancy risk is lower than assumed, and its costs are reduced by the introduction of equally effective biosimilars. Together, these trends allow for a more prominent role for anti-TNF antibodies in future treatment of paediatric CD.

[Transition from paediatric to adult care: management of adolescents with inflammatory bowel disease]. / Transitie van kinder- naar volwassenenzorg.

The transfer of adolescent patients with inflammatory bowel disease (IBD) to adult gastroenterology services is often troublesome. Failed transition can have adverse effects on the course of disease. We present two cases of adolescent IBD patients and their transition process. We identify requirements for successful transition and discuss potential barriers. We illustrate and emphasise that the medical teams on each side (paediatric and adult), as well as the patient and the parents should actively participate in the process of transition. The medical team should, preferably during a local transition clinic, regularly evaluate disease knowledge and self-management skills of the patient and make an individual transition plan to fill the gaps in knowledge and/or skills. Patients should be willing to learn to become more independent and parents should be stimulated to create an environment so that their child can actually try to become more independent. Lastly, we present the Rotterdam model for transition of IBD patients.

Top-down Infliximab Study in Kids with Crohn's disease (TISKids): an international multicentre randomised controlled trial.

INTRODUCTION: Crohn's disease (CD) is a chronic inflammatory disease predominantly affecting the gastrointestinal tract. CD usually requires lifelong medication and is accompanied by severe complications, such as fistulae and strictures, resulting in surgery. Infliximab (IFX) is very effective for treating paediatric patients with CD, but is currently only registered for therapy refractory patients-the so-called step-up strategy. We hypothesise that using IFX first-line, that is, top-down, will give more mucosal healing, fewer relapses, less complications, need for surgery and hospitalisation. METHODS AND ANALYSIS: This international multicentre open-label randomised controlled trial includes children, aged 3-17 years, with new-onset, untreated CD with moderate-to-severe disease activity (weighted Paediatric Crohn's Disease Activity Index (wPCDAI)>40). Eligible patients will be randomised to top-down or step-up treatment. Top-down treatment consists of 5 IFX infusions combined with azathioprine (AZA). After these 5 infusions, patients will continue AZA. Patients randomised to step-up will receive standard induction treatment, either oral prednisolone or exclusive enteral nutrition, combined with AZA as maintenance treatment. The primary outcome is clinical remission (wPCDAI<12.5) at 52 weeks without need for additional CD-related therapy or surgery. Total follow-up is 5 years. Secondary outcomes include clinical disease activity, mucosal healing by endoscopy (at week 10 and optionally week 52), faecal calprotectin, growth, quality of life, medication use and adverse events. ETHICS AND DISSEMINATION: Conducted according to the Declaration of Helsinki and Good Clinical Practice. Medical-ethical approval will be obtained for each site. TRIAL REGISTRATION NUMBER: NCT02517684; Pre-results.

Use of a live attenuated Salmonella enterica serovar Typhimurium vaccine on farrow-to-finish pig farms.

Salmonella enterica infection in pigs is economically important and poses a zoonotic risk. In this study, the efficacy of an attenuated S. enterica serovar Typhimurium strain was evaluated in three farrow-to-finish pig herds. In each herd, 120 piglets were vaccinated orally at 3 and 24 days of age, while 120 piglets served as unvaccinated controls. Faeces, ileocaecal lymph nodes and caecal contents were examined for S. Typhimurium by isolation and serum was analysed for antibodies against S. Typhimurium by ELISA. All pigs were weighed at pre-weaning and slaughter to determine daily weight gain. In vaccinated pigs prior to slaughter, significantly fewer animals excreted S. enterica, there was a significantly lower S. enterica-specific mean antibody titre and there was a significantly higher mean daily weight gain compared to unvaccinated controls. In two herds, there were significantly lower proportions of S. enterica positive ileocaecal lymph nodes and caecal contents at slaughter between the vaccinated and control groups, but this difference was not significant across all three herds. S. enterica with the same auxotrophic characteristics and genotype as the vaccine strain was isolated from several samples of faeces, ileocaecal lymph nodes and caecal contents from vaccinated pigs. These findings indicate that vaccination with an attenuated S. Typhimurium strain reduces S. enterica shedding, but the reduction is not consistent and the vaccine strain may persist in tissues.

Consensus guidelines of ECCO/ESPGHAN on the medical management of pediatric Crohn's disease.

Children and adolescents with Crohn's disease (CD) present often with a more complicated disease course compared to adult patients. In addition, the potential impact of CD on growth, pubertal and emotional development of patients underlines the need for a specific management strategy of pediatric-onset CD. To develop the first evidenced based and consensus driven guidelines for pediatric-onset CD an expert panel of 33 IBD specialists was formed after an open call within the European Crohn's and Colitis Organisation and the European Society of Pediatric Gastroenterolog, Hepatology and Nutrition. The aim was to base on a thorough review of existing evidence a state of the art guidance on the medical treatment and long term management of children and adolescents with CD, with individualized treatment algorithms based on a benefit-risk analysis according to different clinical scenarios. In children and adolescents who did not have finished their growth, exclusive enteral nutrition (EEN) is the induction therapy of first choice due to its excellent safety profile, preferable over corticosteroids, which are equipotential to induce remission. The majority of patients with pediatric-onset CD require immunomodulator based maintenance therapy. The experts discuss several factors potentially predictive for poor disease outcome (such as severe perianal fistulizing disease, severe stricturing/penetrating disease, severe growth retardation, panenteric disease, persistent severe disease despite adequate induction therapy), which may incite to an anti-TNF-based top down approach. These guidelines are intended to give practical (whenever possible evidence-based) answers to (pediatric) gastroenterologists who take care of children and adolescents with CD; they are not meant to be a rule or legal standard, since many different clinical scenario exist requiring treatment strategies not covered by or different from these guidelines.

Evaluation of three intervention strategies to reduce the transmission of Salmonella Typhimurium in pigs.

Despite current control measures, Salmonella in pigs remains a major public health concern. In this in vivo study, the effect of three intervention strategies on Salmonella Typhimurium transmission in pigs was evaluated. The first intervention was feed supplemented with coated calcium-butyrate (group A); the second comprised oral vaccination with a double-attenuated Salmonella Typhimurium strain (group B), and the third was acidification of drinking water with a mixture of organic acids (group C). After challenge at 8 weeks of age, animals were individually sampled for 6 weeks (blood once per week; faeces twice per week) and then were euthanased at 14 weeks of age. Post-mortem ileum, caecum, ileocaecal lymph nodes, and tonsils were sampled, along with ileal, caecal and rectal contents, and tested for the presence of Salmonella spp. Transmission was quantified by calculating an 'adjusted' reproduction ratio 'Ra' and its 95% confidence interval (CI). The proportion of pigs that excreted Salmonella spp. via the faeces was significantly higher in group C (58%, P<0.0001) and the positive control group (41%, P=0.03), compared to group B (15%), and the proportion in group C was also significantly higher than in group A (23%, P=0.01). Group A had the lowest proportion of positive post-mortem samples (18%), followed by group B (31%), the positive control group (41%) and group C (64%) (P<0.03). The highest transmission was seen in the positive control group and group C (Ra=+∞ with 95% CI [1.88; +∞]), followed by group B (Ra=2.61 [1.21; 9.45]) and A (Ra=1.76 [1.02; 9.01]). The results of this study suggest that vaccination and supplementation of the feed with coated calcium-butyrate limited Salmonella transmission in pigs and might be useful control measures.

Small bowel endoscopy in children.

Endoscopic investigation of small bowel pathology in children has historically been difficult due to location, length and tortuosity of the small bowel. Recently, video capsule endoscopy and balloon-assisted enteroscopy techniques have evolved as new diagnostic tools and are increasingly used in the paediatric population. In this review the current literature is appraised to define the clinical indications and practical aspects of capsule endoscopy and balloon-assisted enteroscopy in children.

Rapid test for fecal calprotectin levels in children with Crohn disease.

Assessment of fecal calprotectin, a surrogate marker of mucosal inflammation, is a promising means to monitor therapeutic response in pediatric inflammatory bowel disease, especially if the result is readily available. We tested the performance of a novel calprotectin rapid test, Quantum Blue, versus the conventional enzyme-linked immunosorbent assay in 134 stool samples from 56 pediatric patients with Crohn disease. The intraclass correlation coefficient analysis reflected good agreement (intraclass correlation coefficient 0.97 [95% confidence interval 0.95-0.98]) but agreement was better in lower values, where dilutions were not required. Using a cutoff of 100 µg/g for normal values, the percentage agreement between the 2 tests was 87%. The optimal cutoff values to guide clinical decisions in the therapy of inflammatory bowel disease have yet to be determined.

Assessing the Knowledge and Perceptions of Medical Students from the Western Cape; South Africa; Regarding the Millennium Development Goals

Background: Health science students are key players in implementing the Millennium Development Goals (MDG). Knowledge and understanding at university level is essential to achieve the goals by 2015. The primary objective of this study was to assess the knowledge and perceptions of fifth-year medical students at Stellenbosch University and the University of Cape Town regarding the MDG. The secondary objectives were to determine the degree to which students are involved in awareness campaigns and implementation of the MDG; and to assess students' perceptions regarding the need for the MDG in South Africa. Method: This observational; descriptive; cross-sectional study collected quantitative data. A census was carried out. All participants completed a self-administered questionnaire. Results: Of the 176 participants; 61.14 said they had previously heard or read about the MDG. Forty per cent had heard about the MDG through awareness campaigns. More than half (54.86) claimed to know what the MDG were; but could not name all of the goals. Participants identified a mean of three out of eight MDG correctly. The majority of students considered MDG implementation in South Africa important but ineffective (69.85); and 85.82 believed that the MDG would not be achieved on time.Conclusion: It was found that fifth-year medical students in the Western Cape were not adequately informed about the MDG and their importance in South Africa. However; their perceptions were positive; in that the majority agreed that the implementation of the MDG in South Africa is important and that more needs to be done in creating awareness about the goals

High intra-uterine exposure to infliximab following maternal anti-TNF treatment during pregnancy.

BACKGROUND: Typically, inflammatory bowel disease (IBD) patients are in their reproductive years, raising questions about safely using antitumour necrosis factor antibodies like infliximab (IFX) during pregnancy. IgG antibodies naturally cross the placenta, especially during the last trimester. To prevent foetal intra-uterine exposure, stopping IFX treatment at gestational week 30 is recommended. However, whether this limits intra-uterine and early postnatal IFX exposure is unestablished. AIM: To determine the intra-uterine exposure to IFX following maternal treatment with IFX. METHODS: Four pregnant IBD patients intentionally continued IFX during pregnancy. IFX levels were assessed in newborns' cord blood and the mothers' peripheral blood at delivery. The children's development during the first 3-6 months, infections, vaccine reactions and antibody responses to vaccinations against Haemophilus influenzae type b and Pneumococcus were assessed. RESULTS: The patients stopped IFX therapy at gestational week 21, 26, 26 and 30, respectively. In three infants, therapeutic IFX levels were present in cord blood at levels of 5.5-13.7 µg/mL and were two- to three-fold higher than in the peripheral blood of their mothers. During the 3- to 6-month follow-up, the children developed normally without signs of infections or allergic reactions, and had normal antibody titres after routine childhood vaccinations. CONCLUSION: The use of IFX until gestational week 30 leads to foetal intra-uterine exposure to IFX at levels that exceed those in the mothers' peripheral blood. Although no short-term complications were detected, the high IFX levels observed in newborns raise concerns about unknown effects of IFX on the developing immune system.

The duration of effect of infliximab maintenance treatment in paediatric Crohn's disease is limited.

BACKGROUND: Infliximab is effective for induction and maintenance of remission in children with moderately to severely active Crohn's disease (CD). AIM: To evaluate the long-term efficacy of infliximab treatment in paediatric CD. METHODS: In this observational, multicentre study, all paediatric CD patients in The Netherlands treated with infliximab from October 1992 to November 2009 and with minimal follow-up of 3 months since start of infliximab, were studied. RESULTS: One hundred and fifty-two CD patients [81M; median age at start of infliximab 15.0 years (IQR 13.1-16.4)] received a median number of 10.5 infliximab infusions (IQR 6-21). Median follow-up after start of infliximab was 25 months (IQR 13-40). Kaplan-Meier analysis showed that the cumulative probability of losing response to infliximab in patients who initially required repeated infusions was 13%, 40% and 50% after 1, 3 and 5 years, respectively. Seventy-four patients (49%) needed dose adjustments, with a median time to any adjustment of 6 months. CONCLUSIONS: Duration of effect of infliximab is limited as 50% of patients on infliximab maintenance treatment lose their therapeutic response after 5 years. Dose adjustments after start of infliximab are frequently needed to regain therapeutic benefit. These findings emphasise the need for effective, long-term treatment strategies for paediatric CD.

Complications of single-balloon enteroscopy: a prospective evaluation of 166 procedures.

BACKGROUND AND STUDY AIM: Double-balloon enteroscopy (DBE) has proven to be a relatively safe method for small-bowel evaluation, with a complication rate of 1 %. The main concern after diagnostic DBE is acute pancreatitis. Single-balloon enteroscopy (SBE) has emerged as a viable alternative to DBE. Until now, no incidence of pancreatitis has been reported for SBE. The aims were to evaluate complication rate and occurrence of hyperamylasemia and to identify the risk factors for hyperamylasemia after SBE. PATIENTS AND METHODS: Prospectively, consecutive patients undergoing peroral ("proximal") or combined approach SBE were included. Complications were assessed at 1 and 30 days afterwards. Serum amylase and C-reactive protein (CRP) were assessed immediately before and 2 - 3 hours after SBE. RESULTS: 166 SBE procedures were performed in 105 patients (53-male; mean age 51 years, range 9 - 87). The indications for SBE were: anemia (n = 55), Crohn's disease (n = 31) and abdominal complaints suspicious for inflammatory bowel disease (n = 5), Peutz-Jeghers syndrome (n = 1) and other (n = 13). Therapeutic interventions were performed during 21 procedures (13 %). One perforation (1 / 21 therapeutic interventions, 4.8 %) occurred after dilation of a benign stricture. While 13 patients (16 %) had post-SBE hyperamylasemia, none had complaints suggesting acute pancreatitis. Factors such as sex, indication, procedure duration, number of passes, route of SBE, findings, and/or treatment showed no significant correlation with presence of hyperamylasemia. CONCLUSIONS: SBE appears to be a safe diagnostic endoscopic procedure. The incidence of hyperamylasemia and pancreatitis after peroral SBE seems comparable to that after DBE.

Comparison of exhaled nitric oxide measurements between NIOX MINO electrochemical and Ecomedics chemiluminescence analyzer.

BACKGROUND: Exhaled nitric oxide (eNO) is an established, noninvasive biomarker of active airway inflammation in (atopic) asthma. Treatment with anti-inflammatory therapy, such as inhaled corticosteroids, effectively decreases eNO levels. The NIOX MINO (MINO) is a hand-held, relatively inexpensive, electrochemical device that has been shown to yield comparable eNO measurements to the NIOX stationary unit. AIM: To compare measurements of MINO with another widely used and validated stationary chemiluminescence analyzer, the Ecomedics (ECO). METHODS: We performed subsequent eNO measurements on ECO and MINO in 50 subjects (19 healthy volunteers, 18 healthy smokers and 13 non-smoking, atopic asthmatics, not on controller therapy) on two visits 4-10 days apart. The mean of three acceptable measurements by ECO and the first acceptable measurement with the MINO were used for analysis. RESULTS: Both devices yielded reproducible eNO values for all subjects on both visits, with an overall CV of 22.7% (ECO) and 18.3% (MINO). A significant correlation was found between both devices (r=0.97, p<0.0001). Bland-Altman plots showed a high degree of agreement for the entire study population (mean difference MINO vs ECO=-10%; 95% limit of agreement were -36% and +28%) and in the three individual subgroups. CONCLUSIONS: Exhaled NO values measured with the MINO are reproducible and in agreement with the ECO. Our results add further evidence to the reliability of the MINO and warrant its applicability in research and clinical practice.

Relation between telomerase activity, hTERT and telomere length for intracranial tumours.

Human linear chromosomes are capped by specialized DNA-protein structures called telomeres. The present study analysed the telomerase activity, hTERT protein and telomere length in meningiomas and gliomas in relation to their WHO grading. Fifty-three freshly dissected tumour biopsies were analysed for telomerase activity, hTERT protein expression and telomere length. Telomerase activity was examined in 41 of the 53 biopsies. Telomerase activity was detected in 3 of 35 (8.6%) screened meningiomas (1 benign, 1 atypical and 1 malignant meningioma). For hTERT expression, 56.4% of meningiomas were positive with a mean labelling index (hTERT LI) of 31.3% (SD=26.5) for the hTERT positive meningiomas. The mean telomere length for meningiomas was 6.983 kb (SD=1.969). For gliomas, no active telomerase was detected in 2 low-grade astrocytomas, whereas three of the four screened glioblastomas were positive for telomerase activity. The only hTERT protein positive astrocytoma had a mean labelling index of 9.0%. On the other hand, the hTERT LI for glioblastomas was 53.6% (SD=28.0). The two low-grade astrocytomas had a telomere length of 14.310 and 9.236 kb. The anaplastic astrocytoma had a telomere length of 4.903 kb and the glioblastomas 5.767 kb (SD=2.042). The normal meningeal and neuronal tissue is negative for telomerase activity and hTERT. The length was +/-10.000 kb. These results indicate that telomere shortening may be a critical step in pathogenesis of atypical and malignant meningiomas and gliomas. Critical telomere shortening in vitro was shown to activate telomerase.