This nationwide multicentre study analysed the epidemiology of bacterial, viral and fungal infections in paediatric haematopoietic stem cell transplantation (HSCT) and paediatric haematology and ...oncology (PHO) patients over a period of 24 consecutive months, including incidence, hazard risk and outcome of infections as well as occurrence of multidrug-resistant bacteria. During this period, 308 HSCTs were performed and 1768 children were newly diagnosed for malignancy. Compared to PHO, the risk in HSCT patients was significantly higher for all infections (hazard ratio (HR) 2.7), bacterial (HR 1.4), fungal (HR 3.5) and viral (HR 15.7) infections. The risk was higher in allo- than auto-HSCT for bacterial (HR 1.4), fungal (HR 3.2) and viral (HR 17.7) infections. The incidence of resistant bacteria was higher in HSCT than in PHO patients for both G-negative (72.5% vs. 59.2%) and G-positive (41.4% vs. 20.5%) strains. Cumulative incidence of bacterial, fungal and viral infections in HSCT patients was 33.9, 22.8 and 38.3%, respectively. Cumulative incidence of viral infections in allo-HSCT was 28.0% for cytomegalovirus, 18.5% for BK virus, 15.5% for Epstein-Barr virus, 9.5% for adenovirus, 2.6% for varicella zoster virus, 0.9% for influenza, 0.9% for human herpesvirus 6 and 0.3% for hepatitis B virus. Survival rates from infections were lower in HSCT than in PHO patients in bacterial (96.0 vs. 98.2%), fungal (75.5 vs. 94.6%) and most viral infections. In conclusion, the risk of any infections and the occurrence of resistant bacterial strains in allo-HSCT patients were higher than in auto-HSCT and PHO patients, while the outcome of infections was better in the PHO setting.
The aim was to evaluate the incidence, clinical course, and outcome of adenoviral infection (AdVI) in pediatric patients diagnosed and treated due to cancer and in pediatric recipients of ...hematopoietic stem cell. Over a 72‐month period, all‐in 5599 children with cancer: 2441 patients with hematological malignancy (HM) and 3158 with solid tumors (ST), and 971 patients after transplantation: 741 after allogeneic (allo‐HSCT) and 230 after autologous (auto‐HSCT) were enrolled into the study. Among cancer patients, 67 episodes of AdVI appeared in 63 (1.1%) children, including 45 (1.8%) with HM and 18 (0.6%; P < .001) with ST. Within transplanted patients, AdVIs were responsible for 88 episodes in 81 (8.3%) children (P < .001), including 78 (10.5%) patients after allo‐HSCT and 3 (1.3%) after auto‐HSCT. Time to develop AdVI was short, especially after allo‐HSCT. The most common clinical manifestation in cancer patients was enteritis diagnosed in 63 (94.0%) cases, while among HSCT recipient asymptomatic adenoviremia was found in 36 (40.9%) cases and the most common clinical manifestation was urinary tract infection. Cancer patients with disseminated disease, as well as HSCT recipients with either asymptomatic viremia or disseminated disease, received antiviral treatment. The most commonly used first‐line therapy was cidofovir. None of the cancer patients died due to AdVI, while within HSCT recipients three patients developed disseminated adenoviral disease and died despite antiviral treatment. In cancer patients, AdVIs are rare and associated with very good prognosis even without specific treatment. However, in allo‐HSCT recipients, disseminated disease with fatal outcome is more likely to occur.
Highlights
Low incidence of HAdV causing less severe infections not requiring antiviral therapy but with satisfactory outcome within cancer patients.
In allo‐HSCT recipients disseminated disease requiring antiviral drugs and at risk of fatal outcome is more likely to occur.
Monitoring for HAdV in all patients, and especially in those who underwent AdVI prior to HSCT or had MD or MMUD‐HSCT, at early posttransplantation period should be recommended.
Clostridium difficile
infection (CDI) is one of the most common causes of nosocomial infectious diarrhea in children during anticancer therapy or undergoing hematopoietic stem cell transplantation ...(HSCT) in Europe. Immunosuppression in these patients is a risk factor for CDI. Malignant diseases, age, acute graft-versus-host disease (aGVHD), HLA mismatch, or use of total body irradiation may play an important role in CDI course. The aim of this study was to evaluate the incidence, course, and outcome of CDI in children treated for malignancy or undergoing HSCT. Between 2012 and 2015, a total number of 1846 patients were treated for malignancy in Polish pediatric oncological centers (PHO group) and 342 underwent transplantation (HSCT group). In PHO group, episodes of CDI occurred in 210 patients (14%). The incidence of CDI was higher in patients with hematological malignancies in comparison to that with solid tumors. Patients with acute myeloblastic leukemia had shorter time to episode of CDI than those with acute lymphoblastic leukemia. Patients over 5 years and treated for acute leukemia had more severe clinical course of disease in PHO group. In HSCT group, CDI occurred in 29 (8%) patients. The incidence of CDI was higher in patients transplanted for acute leukemia. The recurrence rate was 14.7% in PHO and 20.7% in HSCT patients. CDI incidence was highest in patients with hematological malignancies. Most of patients experienced mild CDI. Age < 5 years and diagnosis other than acute leukemia were the positive prognostic factors influencing clinical CDI course.
Background
Hodgkin (HL) and non‐Hodgkin lymphoma (NHL) represent a spectrum of lymphoid malignancies that are often curable with currently applied treatment regimens; however, 15%‐30% of lymphoma ...patients still suffer from relapsed or refractory (rel/ref) disease. Although hematopoietic stem cell transplantation (HSCT) improves outcomes of second‐line therapy for lymphoma in childhood, the complication rates in this group of patients, especially infectious complications (IC), remain unclear.
Objective
The aim of this population‐based cohort study was a retrospective analysis of incidence, epidemiology and profile of bacterial infections (BI), invasive fungal disease (IFD), and viral infections (VI) in primary or rel/ref lymphoma patients, both HL and NHL.
Patients and methods
We subdivided lymphoma patients into three groups: patients with primary conventional chemotherapy/radiotherapy regimens (group A), patients with rel/ref lymphoma treated with second‐line chemotherapy (group B), and rel/ref lymphoma patients who underwent HSCT (group C). The medical records of the patients were biannually reported by each pediatric oncology center, and the data were analyzed centrally.
Results
Within 637 patients with primary lymphoma, at least one IC was diagnosed in 255 (40.0%), among 52 patients with rel/ref lymphoma 24 (46.2%) ICs were observed, and in transplanted group, 28 (57.1%) out of 49 children were diagnosed with IC (P = .151). The distribution of etiology of IC differed between the patient groups (A, B, C), with a predominance of BI in group A (85.6% vs 72.0% and 47.9%, respectively), VI in group C (9% and 16.0% vs 46.6%, respectively), and IFD in group B (5.4% vs 12.0% vs 5.5%, respectively). Overall, 500 (68.0%) episodes of bacterial IC were diagnosed in the entire group. Apart from HL patients treated with chemotherapy, in all the other subgroups of patients Gram‐positives were predominant. The rate of multidrug‐resistant bacteria was high, especially for Gram‐negatives (41.1% in group A, 62.5% in group B, and 84.6% in group C). The infection‐related mortality was comparable for each group.
Conclusions
The incidence of IC was comparable during first‐ and second‐line chemotherapy and after HSCT, but their profile was different for primary or re/ref lymphoma and depended on the type of therapy.
Regulatory T-cells (Tregs) are a very important subtype of lymphocytes when it comes to self-control in the human immunological system. Tregs are decisive not only in the protection against ...destruction of own tissues by autoimmune immunocompetent cells but also in the immunological answer to developing cancers. On the other hand, Tregs could be responsible for the progression of acute and chronic leukemias. In our study, we review publications available in the PUMED database concerning acute leukemia, with a particular emphasis on child's leukemias. The percentage of regulatory T-lymphocytes in peripheral blood and bone marrow was elevated compared to those in healthy individuals and correlated with progressive disease. Regulatory T-cells taken from children diagnosed with leukemia showed a higher suppressive capability, which was confirmed by detecting elevated levels of secreted IL-10 and TGF-beta. The possibility of pharmacological intervention in the self-control of the immunological system is now under extensive investigation in many human cancers. Presumably, Treg cells could be a vital part of targeted therapies. Routine Treg determination could be used to assess the severity of disease and prognosis in children with acute lymphoblastic leukemia. This proposition results from the fact that in some studies, higher percentage of Treg cells in peripheral blood was demonstrated. However, observations confirming these facts are scarce; thus, extrapolating them to the population of children with hematological malignancies needs to be verified in additional studies.
CD4.sup.+CD25.sup.highCD127.sup.low/-FoxP.sub.3.sup.+ regulatory T cells (Tregs) are currently under extensive investigation in childhood acute lymphoblastic leukemia (ALL) and in other human ...cancers. Usually, Treg cells maintain the immune cell homeostasis. This small subset of T cells has been, in fact, considered to be involved in the pathogenesis of autoimmune diseases and progression of acute and chronic leukemias. However, whether Treg dysregulation in CLL and ALL plays a key role or it rather represents a simple epiphenomenon is still a matter of debate. Treg cells have been proposed as a prognostic indicator of the clinical course of the disease and might also be used for targeted immune therapy. Our study revealed statistically higher percentage of Treg cells in the bone marrow than in peripheral blood in the group of 42 children with acute lymphoblastic leukemia. By analyzing Treg subpopulations, it was shown that only memory Tregs in contact with leukemic antigens showed statistically significant differences. We noticed a low negative correlation between Treg cells in the bone marrow and the percentage of blasts (R = -0.36) as well as a moderate correlation between Treg cells in the bone marrow and Hb level (R =+0.41) in peripheral blood before therapy. The number of peripheral blood blasts on day 8th correlates negatively (R = -0.36) with Tregs. Furthermore, statistical analysis revealed low negative correlation between the number of Tregs in the bone marrow and the minimal residual disease measured on day 15th, the percentage of blasts in the bone marrow and leukocytosis after 15 days of chemotherapy. These results indicate the influence of Tregs on the final therapeutic effect.
Regulatory T-cells (Tregs) are a very important subtype of lymphocytes when it comes to self-control in the human immunological system. Tregs are decisive not only in the protection against ...destruction of own tissues by autoimmune immunocompetent cells but also in the immunological answer to developing cancers. On the other hand, Tregs could be responsible for the progression of acute and chronic leukemias. In our study, we review publications available in the PUMED database concerning acute leukemia, with a particular emphasis on child’s leukemias. The percentage of regulatory T-lymphocytes in peripheral blood and bone marrow was elevated compared to those in healthy individuals and correlated with progressive disease. Regulatory T-cells taken from children diagnosed with leukemia showed a higher suppressive capability, which was confirmed by detecting elevated levels of secreted IL-10 and TGF-beta. The possibility of pharmacological intervention in the self-control of the immunological system is now under extensive investigation in many human cancers. Presumably, Treg cells could be a vital part of targeted therapies. Routine Treg determination could be used to assess the severity of disease and prognosis in children with acute lymphoblastic leukemia. This proposition results from the fact that in some studies, higher percentage of Treg cells in peripheral blood was demonstrated. However, observations confirming these facts are scarce; thus, extrapolating them to the population of children with hematological malignancies needs to be verified in additional studies.
CD4+CD25highCD127low/−FoxP3+ regulatory T cells (Tregs) are currently under extensive investigation in childhood acute lymphoblastic leukemia (ALL) and in other human cancers. Usually, Treg cells ...maintain the immune cell homeostasis. This small subset of T cells has been, in fact, considered to be involved in the pathogenesis of autoimmune diseases and progression of acute and chronic leukemias. However, whether Treg dysregulation in CLL and ALL plays a key role or it rather represents a simple epiphenomenon is still a matter of debate. Treg cells have been proposed as a prognostic indicator of the clinical course of the disease and might also be used for targeted immune therapy. Our study revealed statistically higher percentage of Treg cells in the bone marrow than in peripheral blood in the group of 42 children with acute lymphoblastic leukemia. By analyzing Treg subpopulations, it was shown that only memory Tregs in contact with leukemic antigens showed statistically significant differences. We noticed a low negative correlation between Treg cells in the bone marrow and the percentage of blasts (R=−0.36) as well as a moderate correlation between Treg cells in the bone marrow and Hb level (R=+0.41) in peripheral blood before therapy. The number of peripheral blood blasts on day 8th correlates negatively (R=−0.36) with Tregs. Furthermore, statistical analysis revealed low negative correlation between the number of Tregs in the bone marrow and the minimal residual disease measured on day 15th, the percentage of blasts in the bone marrow and leukocytosis after 15 days of chemotherapy. These results indicate the influence of Tregs on the final therapeutic effect.
Seventy-four neuroblastoma patients were analyzed according to the clinical data including age, stage, bone metastases, primary tumor localization, tumor diameter, LDH, and serum ferritin. ...Histological examination of tumor specimens comprised calculation of proliferative index (PI) on slides stained with anti Ki-67 antibody and assessment of microvascular density (MVD) on anti-CD34 stained sections. Wide range of PI (1.5-79; median 37.8%) and MVD (41-385; median 172/mm2) values was observed. Significant relationship between higher PI and tumor diameter more than 5 cm (40.3 vs 37.2%) was found. Lower PI was found more frequently in stroma-rich tumors. Significantly higher median MVD was found in infant tumors and in smaller tumors <5 cm. Tendency to inverse relationship between PI and MVD was observed. The high values of both PI and MVD were found in some aggressive tumors in patients >1-year old. We evaluated the new parameter: proliferative-vascular index (PVI) as PVI=PIxMVD which ranged from 213-18333. Among eleven patients >1 year old, with PVI >7000, seven (64%) had a poor outcome within the mean period of 22 months. Our results suggest that the simultaneous estimation of proliferative activity and vascularity of neuroblastomas could be studied as a prognostic indicator. Further investigations are needed to confirm this finding.
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![[CD4.sup.+][CD25.sup.high][...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/2314-8861/small "[CD4.sup.+][CD25.sup.high][CD127.sup.low/-][FoxP.sub.3.sup.+] Regulatory T-Cell Population in Acute Leukemias: A Review of the Literature")
