Clonal relapse dynamics in acute myeloid leukemia following allogeneic hematopoietic cell transplantation.

Patients with acute myeloid leukemia (AML) who experience relapse following allogeneic hematopoietic cell transplantation (alloHCT) face unfavorable outcomes regardless of the chosen relapse treatment. Early detection of relapse at the molecular level by measurable residual disease (MRD) assessment enables timely intervention, which may prevent hematological recurrence of the disease. It remains unclear whether molecular MRD assessment can detect MRD before impending relapse and, if so, how long in advance.

MRD as Biomarker for Response to Donor Lymphocyte Infusion after Allogeneic Hematopoietic Cell Transplantation in Patients with AML.

Donor lymphocyte infusions (DLIs) can directly target leukemic cells through a graft-versus-leukemia effect and play a key role in the prevention and management of relapse after allogeneic hematopoietic cell transplantation (alloHCT). Predictors of response to DLIs are not well established. We evaluated measurable residual disease (MRD) before, 30 and 90 days after DLI treatment as biomarkers of response.

Multimodal Treatment of Nasopharyngeal Carcinoma in Children, Adolescents and Young Adults-Extended Follow-Up of the NPC-2003-GPOH Study Cohort and Patients of the Interim Cohort.

Nasopharyngeal carcinoma (NPC) in children and young adults has been treated within two consecutive prospective trials in Germany, the NPC-91 and the NPC-2003 study of the German Society of Pediatric Oncology and Hematology (GPOH). In these studies, multimodal treatment with induction chemotherapy, followed by radio (chemo)therapy and interferon-beta maintenance, yielded promising survival rates even after adapting total radiation doses to tumor response. The outcome of 45 patients in the NPC-2003 study was reassessed after a median follow-up of 85 months.

Posttransplantation MRD monitoring in patients with AML by next-generation sequencing using DTA and non-DTA mutations.

Next-generation sequencing (NGS)-based measurable residual disease (MRD) monitoring in patients with acute myeloid leukemia (AML) is widely applicable and prognostic prior to allogeneic hematopoietic cell transplantation (alloHCT). We evaluated the prognostic role of clonal hematopoiesis-associated DNMT3A, TET2, and ASXL1 (DTA) and non-DTA mutations for MRD monitoring post-alloHCT to refine MRD marker selection. Of 154 patients with AML, 138 (90%) had at least one mutation at diagnosis, which were retrospectively monitored by amplicon-based error-corrected NGS on day 90 and/or day 180 post-alloHCT.

Low serum neutralizing anti-SARS-CoV-2 S antibody levels in mildly affected COVID-19 convalescent patients revealed by two different detection methods.

Neutralizing antibodies targeting the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) block severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) entry into cells via surface-expressed angiotensin-converting enzyme 2 (ACE2). We used a surrogate virus neutralization test (sVNT) and SARS-CoV-2 S protein-pseudotyped vesicular stomatitis virus (VSV) vector-based neutralization assay (pVNT) to assess the degree to which serum antibodies from coronavirus disease 2019 (COVID-19) convalescent patients interfere with the binding of SARS-CoV-2 S to ACE2. Both tests revealed neutralizing anti-SARS-CoV-2 S antibodies in the sera of ~90% of mildly and 100% of severely affected COVID-19 convalescent patients.

Postinfectious Onset of Myasthenia Gravis in a COVID-19 Patient.

We report the case of a young woman with postinfectious onset of myasthenia gravis after COVID-19 with mild respiratory symptoms and anosmia/ageusia 1 month before admission to our neurological department. Patient data were derived from medical records of Hannover Medical School, Germany. Written informed consent was obtained from the patient.

Seropositivity for pathogens associated with chronic infections is a risk factor for all-cause mortality in the elderly: findings from the Memory and Morbidity in Augsburg Elderly (MEMO) Study.

Immunostimulation by chronic infection has been linked to an increased risk for different non-communicable diseases, which in turn are leading causes of death in high- and middle-income countries. Thus, we investigated if a positive serostatus for pathogens responsible for common chronic infections is individually or synergistically related to reduced overall survival in community dwelling elderly. We used data of 365 individuals from the German MEMO (Memory and Morbidity in Augsburg Elderly) cohort study with a median age of 73 years at baseline and a median follow-up of 14 years.

Leptomeningeal Metastasis: The Role of Cerebrospinal Fluid Diagnostics.

Metastatic spread into the cerebrospinal fluid (CSF) represents a severe complication of malignant disease with poor prognosis. Although early diagnosis is crucial, broad spectrums of clinical manifestations, and pitfalls of magnetic resonance imaging (MRI) and CSF diagnostics can be challenging. Data are limited how CSF parameters and MRI findings relate to each other in patients with leptomeningeal metastasis.

The Influence of Blood Contamination on Cerebrospinal Fluid Diagnostics.

Blood contamination due to traumatic lumbar puncture presents a diagnostic pitfall in cerebrospinal fluid (CSF) analysis. It is controversially discussed if phagocytosis of erythrocytes which can be found in the CSF after subarachnoid hemorrhage can also develop in the presence of artificial blood contamination. Furthermore, there is no consensus about the acceptable amount of artificial blood contamination on CSF protein results.

High antibiotic prescription rates in hospitalized children with human metapneumovirus infection in comparison to RSV infection emphasize the value of point-of-care diagnostics.

Background: Respiratory infections are the main causes for hospitalization in children and a common reason for the initiation of antibiotic treatment. Rapid antigen detection tests and point-of-care mPCR-based assays provide a fast detection of viral pathogens. Nonetheless, the prescription rate of antibiotics for respiratory infections is exceedingly high.

The 2009 pandemic influenza A(H1N1) coincides with changes in the epidemiology of other viral pathogens causing acute respiratory tract infections in children.

Background: In Germany, the outbreak of the novel pandemic 2009 influenza A(H1N1) virus A(H1N1)pdm09 caused a wave of high activity between November 2009 and January 2011. The aim of this study was to investigate the prevalence of 19 respiratory pathogens in children hospitalized for lower respiratory tract infections during the winter influenza seasons of 2009/2010 and 2010/2011 and to observe a possible impact of influenza A(H1N1)pdm09 on the epidemiology of other epidemic viruses.

Materials And Methods: Specimens were nasopharyngeal aspirates which had been collected from children admitted to the participating hospitals in the area of Mainz, Wiesbaden, and Kiel, Germany, with acute community-acquired lower respiratory tract infections.

Validation of a multiplex reverse transcriptase PCR ELISA for the detection of 19 respiratory tract pathogens.

Introduction: Since acute respiratory tract infections inflict a high burden of disease in children worldwide, a multiplex reverse transcription polymerase chain reaction combined with a microwell hybridization assay (m-RT-PCR-ELISA) to detect 19 different respiratory pathogens was developed and validated.

Methods: A total of 430 respiratory specimens were retrospectively tested in parallel by both the advanced 19-valent m-RT-PCR-ELISA as well as by culture or individual RT-PCR assays used in clinical routine.

Results: The mean (median) sensitivity of the m-RT-PCR-ELISA in the retrospective test was 93.

Prolonged detection of herpes simplex virus type 2 (HSV-2) DNA in cerebrospinal fluid despite antiviral therapy in a patient with HSV-2-associated radiculitis.

Herpes simplex virus type 2 (HSV-2) can cause radiculo-myelitis as a neurological manifestation. We report a case of ongoing HSV-2 DNA positivity in the cerebrospinal fluid (CSF) of at least eight weeks under antiviral therapy with acyclovir in a highly immunocompromised hemato-oncologic patient with HSV-2-associated radiculitis. Upon admission, the patient presented with pain, leg paresis, and urinary incontinence, as well as pleocytosis in the CSF.

Are meteorological parameters associated with acute respiratory tract infections?

Background: Information on the onset of epidemics of acute respiratory tract infections (ARIs) is useful in timing preventive strategies (eg, the passive immunization of high-risk infants against respiratory syncytial virus [RSV]). Aiming at better predictions of the seasonal activity of ARI pathogens, we investigated the influence of climate on hospitalizations for ARIs.

Methods: Samples obtained from 3044 children hospitalized with ARIs in Mainz, Germany, were tested for pathogens with a multiplex reverse-transcriptase polymerase chain reaction enzyme-linked immunosorbent assay from 2001 through 2006.

PID-ARI.net - a pediatric infectious diseases network on acute respiratory infections and the added value of a multilevel research network.

Background: PID-ARI.net was one of three infectious disease epidemiological research networks funded by the German Ministry of Education and Research (BMBF). Its objectives were to strengthen the national initiative on infectious diseases epidemiology and to focus on a health care problem of high relevance.

Lower respiratory tract disease in children: constant pathogens - constant management?!

Background: This study analyses the pathogens of acute lower respiratory tract infections (LRI) in children in a German community hospital over six years. Against this background the adoption of new diagnostic and therapeutic guidelines for the LRI management and of RSV-cases in particular is studied.

Methods: 1054 children aged zero to 36 months hospitalized with LRI were prospectively included in the surveillance studies "Parainfluenzavirus (PIV) and Respiratory syncytial virus (RSV) infections in Germany [PRI.

Diagnostic performance of a rapid antigen test for RSV in comparison with a 19-valent multiplex RT-PCR ELISA in children with acute respiratory tract infections.

A rapid and reliable diagnosis of respiratory syncytial virus (RSV) infection in childhood is very important for clinical management. In this study we compared a rapid antigen test (enzyme immunoassay, EIA) for the detection of RSV with a reverse transcriptase polymerase chain reaction (RT-PCR) [19-valent multiplex RT-PCR enzyme-linked immunosorbent assay (ELISA)] to assess the diagnostic performance. Furthermore the diagnostic value of the EIA in terms of age and season relation was analyzed.

Ten years' experience with year-round active surveillance of up to 19 respiratory pathogens in children.

Introduction: Surveillance systems for acute respiratory infections (ARI) in children currently are often limited in terms of the panel of pathogens and the age range investigated or are only syndromic and at times only active in the winter season.

Methods: Within PID-ARI.net, a research network for ARI in children in Germany, an active, year-round surveillance system was formed in three regions from north to south for population-based analysis.

No temporal association between influenza outbreaks and invasive pneumococcal infections.

Objective: To assess whether the influenza peak in populations precedes the annual peak for invasive pneumococcal infections (IPI) in winter.

Design: Ecological study. Active surveillance data on influenza A and IPI in children up to 16 years of age collected from 1997 to 2003 were analysed.

Novel human metapneumovirus sublineage.

In a pediatric surveillance network, 287 (5.1%) of 5,580 specimens from patients with acute respiratory infections tested positive for human metapneumovirus (HMPV). Phylogenetic analysis of N- and F-gene sequences of identified HMPV showed that 30% belonged to a novel phylogenetic cluster.

The descriptive epidemiology of severe lower respiratory tract infections in children in Kiel, Germany.

Background: Lower respiratory tract infections (LRI) inflict a high burden of disease in children worldwide. Longitudinal, descriptive epidemiological data on different forms of LRI are urgently needed to differentiate this burden, compare population-based incidence rates between countries and to recognize trends.

Patients And Methods: From July 1996 to June 2000, all children hospitalized with LRI, i.

Comparison of the BD Directigen Flu A+B Kit and the Abbott TestPack RSV with a multiplex RT-PCR ELISA for rapid detection of influenza viruses and respiratory syncytial virus.

The Directigen Flu A+B enzyme immunoassay and the Abbott TestPack RSV enzyme immunoassay were each compared with a multiplex RT-PCR ELISA by testing 635 nasopharyngeal aspirates collected from children aged < 16 years who had been hospitalised with acute respiratory tract infection during the epidemic season 2002-2003. In this study, the sensitivity of the Directigen Flu A+B assay was unacceptably low (29.3% and 10.

Population-based incidence of severe pneumonia in children in Kiel, Germany.

Background: Elaborated data on the descriptive epidemiology of community-acquired pneumonia (CAP) are a prerequisite to estimate the impact of new vaccines.

Patients And Methods: From July 1996 to June 2000, all children (0-16 years) admitted to one of the two pediatric hospitals in Kiel and being resident in the municipal area of Kiel were investigated by cross-sectional studies and prospective testing using a 9-valent in-house m-RT-PCR method.

Results: In the 4-year period, 514 children were included (mean age 46, median 40 months): 279 were diagnosed with bronchopneumonia (BPN, median age 26 months), 235 with pneumonia (PN) (47 months); within the latter 69 cases had lobar PN (55 months), 41 atypical PN (51 months) and 28 parapneumonic effusions (74 months).