Kathrin Seidemann

Monitoring of Adenovirus Infection in Pediatric Transplant Recipients by Quantitative PCR: Report of Six Cases and Review of the Literature

Adenoviral (AdV) infections after transplantation remain a challenge in pediatric patients. Qualitative and quantitative PCR offer new approaches to early diagnosis and monitoring. However, their role in the management of AdV infections in pediatric transplant recipients remains to be determined.

Polymorphisms of methylenetetrahydrofolate reductase (MTHFR) and susceptibility to pediatric acute lymphoblastic leukemia in a German study population

BackgroundMethylenetetrahydrofolate reductase (MTHFR) has a major impact on the regulation of the folic acid pathway due to conversion of 5,10-methylenetetrahydrofolate (methylene-THF) to 5-methyl-THF. Two common polymorphisms (677C>T and 1298A>C) in the gene coding for MTHFR have been shown to reduce MTHFR enzyme activity and were associated with the susceptibility to different disorders, including vascular disease, neural tube defects and lymphoid malignancies. Studies on the role of these polymorphisms in the susceptibility to acute lymphoblastic leukemia (ALL) led to discrepant results.MethodsWe retrospectively evaluated the association of the MTHFR 677C>T and 1298A>C polymorphisms with pediatric ALL by genotyping a study sample of 443 ALL patients consecutively enrolled onto the German multicenter trial ALL-BFM 2000 and 379 healthy controls. We calculated odds ratios of MTHFR genotypes based on the MTHFR 677C>T and 1298A>C polymorphisms to examine if one or both of these polymorphisms are associated with pediatric ALL.ResultsNo significant associations between specific MTHFR variants or combinations of variants and risk of ALL were observed neither in the total patient group nor in analyses stratified by gender, age at diagnosis, DNA index, immunophenotype, or TEL/AML1 rearrangement.ConclusionOur findings suggest that the MTHFR 677C>T and 1298A>C gene variants do not have a major influence on the susceptibility to pediatric ALL in the German population.

Primary Mediastinal Large B-Cell Lymphoma With Sclerosis in Pediatric and Adolescent Patients: Treatment and Results From Three Therapeutic Studies of the Berlin-Frankfurt-Münster Group

PURPOSE Primary mediastinal large B-cell lymphoma with sclerosis (PMLBL) is a rare entity of non-Hodgkins lymphoma (NHL) arising from thymic mature B cells. Optimal treatment strategies remain to be established, especially in pediatric patients. PATIENTS AND METHODS This study analyzes clinical characteristics and treatment outcome of 30 pediatric patients with PMLBL, diagnosed in multicenter therapy NHL-Berlin-Frankfurt-Münster Group (BFM) trials. Treatment was stratified by stage and serum lactate dehydrogenase (LDH) and consisted of four to six 5-day courses of chemotherapy using steroids, oxazaphosphorine alkylating agents, methotrexate, cytarabine, etoposide, and doxorubicin. Radiation was not part of the protocol. RESULTS From April 1986 to August 1999, 1,650 patients with newly diagnosed NHL were enrolled in the NHL-BFM trials; 30 patients (1.8%) had PMLBL. Median age was 14.3 years (range, 1.4 to 16.7 years); 15 patients were male and 15 patients were female. With a median observation time of 5 years (range, 1 to 12 years), probability of event-free survival (pEFS) at 5 years was 0.70 (SE, 0.08). Two patients erroneously diagnosed as T-cell NHL received non-B-cell therapy and died from progress of disease. Events in 28 patients receiving B-cell therapy included early progress during therapy (n = 1) and relapse (n = 6). Residual mediastinal masses were present in 23 patients after two courses of therapy and in 15 patients after the end of therapy. LDH > or = 500 U/L was associated with increased risk of failure in multivariate analysis. CONCLUSION PMLBL mainly is found in adolescents. Dose-intense chemotherapy including high-dose methotrexate yields a pEFS at 5 years of 0.70 (SE, 0.08). LDH is of prognostic value in pediatric patients with PMLBL.

Varicella vaccination in a child with acute lymphoblastic leukaemia

In July, 2003, during reinduction treatment 5 months after diagnosis of acute lymphoblastic leukaemia (ALL), a 4-yearold girl presented with generalised tonic-clonic seizures. She had been treated according to protocol ALL-BFM 2000. Cranial CT and analysis of cerebrospinal fl uid showed no signs of cerebral haemorrhage. Ultra sonography showed an enlarged liver and no signs of ascites or veno-occlusive disease. Her skin appeared normal, with no vesicular rashes. Blood tests showed only raised concentrations of aminotransferases. During the next few hours, she developed respiratory insuffi ciency, petechiae, haematomas, and vesicular lesions of the oral and vagi nal mucosal. On the assumption of an underlying infec tious cause, intravenous treatment with piperacillin, sulbactam, tobramycin, IgG, and aciclovir was initiated. 48 h after the fi rst seizure, her laboratory test results deteriorated, with aspartate and alanine aminotransferase concentrations increasing to 20 864 U/L and 16 029 U/L, respectively, and the full blood cell count indicated pancytopenia. Within 12 h, she developed multi-organ failure (liver, renal, and circulatory failure, and acute respiratory distress syndrome [ARDS]), necessitating artifi cial ventilation. Serostatus for varicella-zoster virus (VZV) was negative, but PCR for VZV was positive in peripheral blood samples (7×106 genome copies per mL). VZV was also isolated from a nasopharyngeal swab but not from cerebrospinal fl uid. PCR analysis of peripheral blood was negative for hepatitis B and C viruses, herpes simplex virus 1 and 2, Epstein-Barr virus, cytomegalovirus, adenovirus, enterovirus, human herpes virus 6, and parvovirus B19. High doses of VZVIgG were added to the treatment. Despite haemo dialysis and ventilation, the child died of progressive ARDS and multi-organ failure 10 days after admission. On receiving the positive VZV-PCR results, the mother recalled that her daughter had received live attenuated VZV vaccine (Varilrix) at another hospital 32 days before the onset of symptoms. Partial sequencing of VZV genes 38 and 54 isolated from the patient excluded a wild-type VZV infection and showed that viraemia was caused by the VZV vaccine strain OKA (fi gure). Vaccination was done 5 months after complete remission had been achieved; at that time lymphocyte count was more than 1·5×109/L, and chemotherapy was interrupted for 1 week before and after vaccination. Deaths after vaccinations with numerous attenuated viruses are well established. Fatal wild-type VZV infections have been reported in ALL patients during chemotherapy and after bone-marrow cell transplantation. Therefore, VZV vaccination is a useful, and generally accepted, therapeutic measure for patients with ALL in remission. Studies of VZV vaccination 3–4 months after autologous stem-cell transplantation, and in early ALL maintenance therapy, did not show fatal side-eff ects. However, any interruption of maintenance therapy in ALL can adversely aff ect outcome for the patient. In our patient, liver failure developed 5 weeks after VZV vaccination, which indicates longstanding replication of OKA strain in the liver. This suggestion accords with observations of late onset of complications (fever, vesicles, and severe hepatitis) in immunocompromised patients after VZV vaccination. Therefore, although we cannot fully exclude that intensifi cation of chemotherapy could have aggravated her symptoms, we suggest that VZV vaccination in seronegative children with leukaemia, who are in complete remission for at least 12 months, should not be undertaken until at least 9 months after the end of immunosuppressive treatment (including maintenance therapy) and not before a lymphocyte count of at least 1·5×109/L has been ascertained. In addition, high-risk patients should remain under close surveillance in the critical phase (6 weeks after vaccination) so that immediate antiviral treatment with aciclovir can be initiated in symptomatic children.

MTHFR 677 (C→T) polymorphism is not relevant for prognosis or therapy-associated toxicity in pediatric NHL: results from 484 patients of multicenter trial NHL-BFM 95

We analyzed the relationship of genetic variation within the methylenetetrahydrofolate reductase gene (MTHFR 677 C→T) with clinical characteristics, outcome, and therapy-related toxicity in pediatric non-Hodgkin’s lymphoma (NHL) in our multicenter trial NHL-BFM 95. In this trial, high-dose methotrexate (MTX) infusion regimens were randomized (4- vs 24-h infusion) in patients with B-cell lymphoma; MTX was applied as 24-h infusion in all patients with lymphoblastic lymphoma and anaplastic large cell lymphoma. Toxicity data were collected per patient and therapy course according to National Cancer Institute Common Toxicity Criteria (NCI-CTC). The genotypes in 484 pediatric patients were distributed as follows: MTHFR 677 CC, 206 patients (42.6%); MTHFR 677 CT, 214 patients (44.2%); and MTHFR 677 TT, 64 patients (13.2%). Lymphoblastic lymphoma was significantly associated with homozygosity for the MTHFR 677 T allele. No association of MTHFR 677 genotype with clinical characteristics (sex, age, and tumor stage), outcome, or therapy-related toxicity could be detected. Therefore, we conclude that the MTHFR 677 C→T polymorphism does not appear to influence outcome or therapy-associated toxicity in pediatric patients with NHL treated on BFM protocols.

Tumor Necrosis Factor and Lymphotoxin Alfa Genetic Polymorphisms and Outcome in Pediatric Patients With Non-Hodgkin’s Lymphoma: Results From Berlin-Frankfurt-Münster Trial NHL-BFM 95

PURPOSE To analyze the association of genetic variation within the tumor necrosis factor (TNF -308 [G-->A]) and lymphotoxin alfa (LT-a +252 [A-->G]) genes with outcome in non-Hodgkins lymphoma of childhood and adolescence. PATIENTS AND METHODS Genotyping of the TNF -308 (G-->A) and LT-a +252 (A-->G) polymorphisms in patients (n = 488) enrolled onto the German-Austrian-Swiss multicenter trial NHL-BFM 95 from April 1996 to January 2000 was performed by polymerase chain reaction with subsequent restriction fragment length polymorphism analysis on DNA from tumor-free specimen. RESULTS In patients with Burkitts lymphoma (BL) and B-cell acute lymphoblastic leukemia (B-ALL; n = 219, 211 eligible patients), patients carrying at least two variant alleles (high-producer haplotypes) had an increased risk of events: probability of event-free survival (pEFS) at 3 years was 81% (SE = 5%), compared with 91% (SE = 2%) in low-producer haplotypes (P = .018). In BL/B-ALL with high tumor load (lactate dehydrogenase [LDH] > or = 500 U/L; n = 104), pEFS was 69% (SE = 8%) in high-producer versus 85% (SE = 4%) in low-producer haplotypes (P = .05). In multivariate analysis including risk factors for events (LDH > or = 500 U/L, CNS involvement, methotrexate infusion regimen), TNF -308/LT-alpha +252 haplotype kept prognostic relevance: patients with high-producer haplotypes had a 2.34-fold increase in risk of events (P = .048). The TNF -308 (G-->A) and LT-alpha +252 (A-->G) polymorphisms were not associated with pEFS in lymphoblastic lymphoma (n = 101), anaplastic large-cell lymphoma (n = 67), or diffuse large B-cell lymphoma (n = 65), nor with therapy-related toxicity. CONCLUSION The TNF -308 (G-->A) and LT-a +252 (A-->G) polymorphisms were negative prognostic factors in pediatric BL/B-ALL. Among patients with serum LDH > or = 500 U/L, haplotype analysis further determined patients at risk for events.

Concept of "awake venovenous extracorporeal membrane oxygenation" in pediatric patients awaiting lung transplantation.

In patients awaiting LuTx, MV and ECMO are often the last ways to create a bridge to LuTx. Both interventions are associated with a poor posttransplant outcome and survival rate. To improve the results of these patients, new “bridging‐strategies” are necessary. Recent reports demonstrate promising results for the concept of “awake ECMO” in adult patients. To date, no data on this approach in pediatric patients have been available. We therefore describe the use of VV‐ECMO as a treatment strategy for RF in awake pediatric patients. It presents our experiences with the first three children treated using this new concept. Mean amount of time on ECMO was 44 days (range, 11.5–109 days). Two patients were successfully bridged to their LuTx. Both are still alive without any recurrences (24 and three months following LuTx). One patient died before a further LuTx after 109 days on ECMO due to adenoviral infection. Although reintubation was necessary in two patients, and total time being awake while on ECMO was <50%, we conclude that the concept of “awake VV‐ECMO” is feasible for the treatment of RF and can be used as a “bridging therapy” to LuTx.

No evidence for a major role of heterozygous deletion 657del5 within the NBS1 gene in the pathogenesis of non‐Hodgkin's lymphoma of childhood and adolescence

Nijmegen breakage syndrome (NBS) is an autosomal recessive DNA repair disorder with a high predisposition for lymphoid malignancies. The majority of NBS patients carry a homozygous founder mutation (657del5) within the NBS1 gene. The observation of a high incidence of cancer in close relatives of NBS patients suggests a potential pathogenetic role of NBS1 mutations in heterozygotes as well. We assessed the frequency of the 657del5 mutation in 109 paediatric patients with non‐Hodgkins lymphoma (NHL). None of the patients analysed carried a NBS1 allele with the 657del5 mutation, suggesting that this mutation does not play a major role in the pathogenesis of NHL of childhood and adolescence.

In-line filtration minimizes organ dysfunction: new aspects from a prospective, randomized, controlled trial.

BackgroundInfused particles induce thrombogenesis, impair microcirculation and modulate immune response. We have previously shown in critically ill children, that particle-retentive in-line filtration reduced the overall complication rate of severe events, length of stay and duration of mechanical ventilation. We now evaluated the influence of in-line filtration on different organ function and thereby elucidated the potential underlying pathophysiological effects of particle infusion.MethodsIn this single-centre, prospective, randomized controlled trial 807 critically ill children were assigned to either control (n = 406) or filter group (n = 401), the latter receiving in-line filtration for complete infusion therapy. Both groups were compared regarding the differences of incidence rates and its 95% confidence interval (CI) of different organ dysfunction as defined by the International Pediatric Sepsis Consensus Conference 2005.ResultsThe incidence rates of respiratory (−5.06%; 95% CI, −9.52 to −0.59%), renal (−3.87%; 95% CI, −7.58 to −0.15%) and hematologic (−3.89%; 95% CI, −7.26 to −0.51%) dysfunction were decreased in the filter group. No difference was demonstrated for the occurrence rates of cardiovascular, hepatic, or neurologic dysfunction between both groups.ConclusionsIn-line filtration has beneficial effects on the preservation of hematologic, renal and respiratory function in critically ill patients. The presented clinical data further support our hypothesis regarding potential harmful effects of particles. In critically ill patients infused particles may lead to further deterioration of the microcirculation, induce a systemic hypercoagulability and inflammation with consecutive negative effects on organ function.Trial registrationClinicalTrials.gov number; NCT00209768

Neonatal aortic arch thrombosis: analysis of thrombophilic risk factors and prognosis.

UNLABELLED Arterial thrombosis in neonates and children is a rare event and is often associated with external risk factors such as asphyxia or sepsis. We report our experiences with two neonates with spontaneous aortic arch thrombosis mimicking aortic coarctation. Despite single case reports until now, no data exist for the underlying thrombophilic risk factors and prognosis of this rare event. Both patients were carriers of a heterozygous factor V Leiden mutation, which has been reported once before as a risk factor for aortic arch thrombosis. One of our patients was operated upon successfully and is alive. The second patient suffered a large infarction of the right medial cerebral artery and had a thrombotic occlusion of the inferior caval vein. The patient obtained palliative care and died at the age of 6 days. In the literature, we identified 19 patients with neonatal aortic arch thrombosis. Of the 19 patients, 11 (58%) died. Including the two reported patients, the mortality rate of patients with multiple thromboses was 80% (8/10) compared with 18% (2/11) for patients with isolated aortic arch thrombosis; this difference reached statistical significance (p = 0.009). The analysis of thrombophilic disorders revealed that factor V Leiden mutation and protein C deficiency seem to be the most common risk factors for aortic arch thrombosis. CONCLUSION Neonatal aortic arch thrombosis is a very rare but life-threatening event, with a high rate of mortality, especially if additional thrombotic complications are present. Factor V Leiden mutation seems to be one important risk factor in the pathogenesis of this fatal disease.