Epidemiology of infections in children with acquired aplastic anaemia: a retrospective multicenter study in Italy

Diagnosis and management of acquired aplastic anemia in childhood. Guidelines from the Marrow Failure Study Group of the Pediatric Haemato-Oncology Italian Association (AIEOP)

Acquired aplastic anemia (AA) is a rare heterogeneous disorder characterized by pancytopenia and hypoplastic bone marrow. The incidence is 2-3 per million population per year in the Western world, but 3 times higher in East Asia. Survival in severe aplastic anemia (SAA) has improved significantly due to advances in hematopoietic stem cell transplantation (HSCT), immunosuppressive therapy, biologic agents, and supportive care. In SAA, HSCT from a matched sibling donor (MSD) is the first-line treatment. If a MSD is not available, options include immunosuppressive therapy (IST), matched unrelated donor, or haploidentical HSCT. The purpose of this guideline is to provide health care professionals with clear guidance on the diagnosis and management of pediatric patients with AA. A preliminary evidence-based document prepared by a group of pediatric hematologists of the Bone Marrow Failure Study Group of the Italian Association of Pediatric Hemato-Oncology (AIEOP) was discussed, modified and approved during a series of consensus conferences that started online during COVID 19 and continued in the following years, according to procedures previously validated by the AIEOP Board of Directors.

Invasive Fungal Diseases in Children with Acute Leukemia and Severe Aplastic Anemia

Although the outcomes of childhood leukemia and severe aplastic anemia (SAA) have improved, infectious complications are still the major concern. Particularly worrisome are invasive fungal diseases (IFDs), one of the most common causes of infectious-related deaths in patients with prolonged neutropenia. A retrospective study was conducted of IFDs in pediatric patients with newly diagnosed or relapsed acute leukemia, or with SAA, at Siriraj Hospital, Mahidol University, Thailand. There were 241 patients: 150 with acute lymphoblastic leukemia (ALL), 35 with acute myeloid leukemia (AML), 31 with relapsed leukemia, and 25 with SAA. Their median age was 5.4 years (range, 0.3–16.0 years). The overall IFD prevalence was 10.7%, with a breakdown in the ALL, AML, relapsed leukemia, and SAA patients of 8%, 11.4%, 19.3%, and 16%, respectively. Pulmonary IFD caused by invasive aspergillosis was the most common, accounting for 38.5% of all infection sites. Candidemia was present in 34.6% of the IFD patients; Candida tropicalis was the most common organism. The overall case-fatality rate was 38.5%, with the highest rate found in relapsed leukemia (75%). The incidences of IFDs in patients with relapsed leukemia and SAA who received fungal prophylaxis were significantly lower than in those who did not (P = N/A and 0.04, respectively). IFDs in Thai children with hematological diseases appeared to be prevalent, with a high fatality rate. The usage of antifungal prophylaxes should be considered for patients with SAA to prevent IFDs.

Clinical Profile and Microbiologic Spectrum of Febrile Neutropenic Episodes in Children With Severe Aplastic Anemia

BACKGROUND

Febrile neutropenia (FN) is a common life-threatening complication in patients with severe aplastic anemia (SAA). However, few studies have examined the spectrum of infections in FN in patients with SAA, especially in children. Therefore, the current study was planned to study the clinicomicrobiologic profile of FN episodes in these children.

MATERIALS AND METHODS

Data of 38 episodes of FN that occurred in 31 children with SAA from November 2015 to April 2017 were collected prospectively and analyzed.

RESULTS

FN episodes occurred more frequently (54.8%) in patients on immunosuppressive therapy. Clinically documented infections accounted for 21 (55.26%) episodes, microbiologically documented infections for 15 (39.47%), bacteremia for 13 (34.21%), and invasive fungal diseases for 6 (15.78%) episodes. Among clinically documented infections, the lower respiratory tract was the commonest site in 23.68% episodes, followed by skin and soft tissue infections. No focus of infection could be identified in 12 (31.57%) episodes. Gram-negative bacteria (71.42%) were the predominant isolates (commonest Klebsiella pneumoniae) over Gram-positive bacteria (commonest coagulase-negative Staphylococcus). High prevalence of aminoglycoside, piperacillin-tazobactam, and carbapenem resistance was noted among Gram-negative organisms. Gram-positive organisms showed excellent sensitivity to vancomycin, linezolid, and clindamycin. The overall mortality rate was 42%.

CONCLUSIONS

Empirical antimicrobial therapy should include adequate coverage for Gram-negative pathogens. The antimicrobial regimen should be modified according to the results of the culture and sensitivity testing.

ESCMID-ECMM guideline: diagnosis and management of invasive aspergillosis in neonates and children

SCOPE

Presenting symptoms, distributions and patterns of diseases and vulnerability to invasive aspergillosis (IA) are similar between children and adults. However, differences exist in the epidemiology and underlying conditions, the usefulness of newer diagnostic tools, the pharmacology of antifungal agents and in the evidence from interventional phase 3 clinical trials. Therefore, the European Society for Clinical Microbiology and Infectious Diseases (ESCMID) and the European Confederation of Medical Mycology (ECMM) have developed a paediatric-specific guideline for the diagnosis and management of IA in neonates and children.

METHODS

Review and discussion of the scientific literature and grading of the available quality of evidence was performed by the paediatric subgroup of the ESCMID-ECMM-European Respiratory Society (ERS) Aspergillus disease guideline working group, which was assigned the mandate for the development of neonatal- and paediatric-specific recommendations.

QUESTIONS

Questions addressed by the guideline included the epidemiology of IA in neonates and children; which paediatric patients may benefit from antifungal prophylaxis; how to diagnose IA in neonates and children; which antifungal agents are available for use in neonates and children; which antifungal agents are suitable for prophylaxis and treatment of IA in neonates and children; what is the role of therapeutic drug monitoring of azole antifungals; and which management strategies are suitable to be used in paediatric patients. This guideline provides recommendations for the diagnosis, prevention and treatment of IA in the paediatric population, including neonates. The aim of this guideline is to facilitate optimal management of neonates and children at risk for or diagnosed with IA.

Fungal Pneumonia in Patients with Hematologic Malignancies and Hematopoietic Cell Transplantation

Invasive fungal infections, which occur primarily as a consequence of prolonged neutropenia and immunosuppression, are a life-threatening complication seen among patients with hematologic malignancies. The routine use of triazole antifungal prophylaxis, enhanced diagnostics, and newer antifungal agents have led to improvements in the care of fungal pneumonias, but invasive fungal infections remain a major cause of morbidity and mortality. This article covers risk factors for major fungal infections, diagnostic approaches, and treatment options for specific fungal pathogens, including Aspergillus and Mucorales species, and discusses current approved strategies for prevention of common and uncommon fungal pneumonias.

[The clinical feature and outcomes of severe aplastic anemia patients suffered from bacteremia following antithymocyte globulin]

Objective: To assess the clinical feature and outcomes of severe aplastic anemia (SAA) patients suffered from bacteremia following antithymocyte globulin (ATG). Methods: A total of 264 cases hospitalized in our hospital between Jan 2000 and July 2011 were enrolled into this study. We evaluated the associated pathogens of bacteremia, analyzed the risk factors by Logistic regression and estimated the overall survival (OS) by Kaplan-Meier method for the cohort of patients. Results: Bloodstream infections occurred in 49 patients, with a median age of 20 (4-62) years, including 38 cases with very SAA (VSAA) and 11 SAA patients. The median time of bacteremia was 13 (2-233) days following ATG administration. The most common microbiologically were Enterobacteriaceae (28.4% ), Pseudomonas aeruginosa (20.9% ) and Klebsiella pneumonia (14.9% ). Almost half (46.9% ) of these bacteria were resistant to most or all available antibacterial classes. Univariate and multivariate analyses demonstrated that VSAA, infections during previous week before ATG treatment were risk factors for bacteremia. The 3 and 6 months response rates (10.6% and 17.0% ) were poor in the patients with bloodstream infections, which were significantly lower than those patients without infections (35.6% and 55.6%, respectively, both P<0.001). The estimated 5-year OS were 36.4% (95%CI 21.3% to 51.5%) and 74.5% (95%CI 68.4% to 80.7%) in the two groups, respectively (P<0.001). Conclusions: ①VSAA has higher risk of bacteremia than SAA; ②Infections during previous week before ATG administration was a risk factor for bacteremia; ③ The outcomes of SAA or VSAA patients suffered from bacteremia following ATG was poor.

Clinical characteristics associated with mortality of patients with anaerobic bacteremia

The presence of anaerobes in the blood stream is known to be associated with a higher rate of mortality. However, few prognostic risk factor analyses examining whether a patient's background characteristics are associated with the prognosis have been reported. We performed a retrospective case-controlled study to assess the prognostic factors associated with death from anaerobic bacteremia. Seventy-four patients with anaerobic bacteremia were treated between January 2005 and December 2014 at Aichi Medical University Hospital. The clinical information included drug susceptibility was used for analysis of prognostic factors for 30-day mortality. Multivariate logistic analyses revealed an association between the 30-day mortality rate and malignancy (OR: 3.64, 95% CI: 1.08-12.31) and clindamycin resistance (OR: 7.93, 95% CI: 2.33-27.94). The result of Kaplan-Meier analysis of mortality showed that the 30-day survival rate was 83% in clindamycin susceptible and 38.1% in clindamycin resistant anaerobes causing bacteremia. The result of log-rank test also showed that susceptibility to clindamycin affected mortality (P < 0.001). Our results indicated that malignancy and clindamycin susceptibility could be used to identify subgroups of patients with anaerobic bacteremia with a higher risk of 30-day mortality. The results of this study are important for the early and appropriate management of patients with anaerobic bacteremia.

Pharmacokinetics and pharmacodynamics of continuous-infusion meropenem in pediatric hematopoietic stem cell transplant patients

This study explored the pharmacokinetics and the pharmacodynamics of continuous-infusion meropenem in a population of pediatric hematopoietic stem cell transplant (HSCT) patients who underwent therapeutic drug monitoring. The relationship between meropenem clearance (CLM) and estimated creatinine clearance (CLCR) was assessed by nonlinear regression. A Monte Carlo simulation was performed to investigate the predictive performance of five dosing regimens (15 to 90 mg/kg of body weight/day) for the empirical treatment of severe Gram-negative-related infections in relation to four different categories of renal function. The optimal target was defined as a probability of target attainment (PTA) of ≥90% at steady-state concentration-to-MIC ratios (C SS/MIC) of ≥1 and ≥4 for MICs of up to 8 mg/liter. A total of 21 patients with 44 meropenem C SS were included. A good relationship between CLM and estimated CLCR was observed (r (2) = 0.733). Simulations showed that at an MIC of 2 mg/liter, the administration of continuous-infusion meropenem at doses of 15, 30, 45, and 60 mg/kg/day may achieve a PTA of ≥90% at a C SS/MIC ratio of ≥4 in the CLCR categories of 40 to <80, 80 to <120, 120 to <200, and 200 to <300 ml/min/1.73 m(2), respectively. At an MIC of 8 mg/liter, doses of up to 90 mg/kg/day by continuous infusion may achieve optimal PTA only in the CLCR categories of 40 to <80 and 80 to <120 ml/min/1.73 m(2). Continuous-infusion meropenem at dosages up to 90 mg/kg/day might be effective for optimal treatment of severe Gram-negative-related infections in pediatric HSCT patients, even when caused by carbapenem-resistant pathogens with an MIC of up to 8 mg/liter.

Bacterial bloodstream infections and antimicrobial susceptibility pattern in pediatric hematology/oncology patients after anticancer chemotherapy

Purpose

Bloodstream infections in pediatric hematology and oncology represent a major problem worldwide, but this has not been studied in Qatar. In this study, we investigated the burden of infection and the resistance pattern in the bacterial etiology, in the only tertiary pediatric hematology and oncology center in Qatar.

Methods

All pediatric cancer patients (n=185) were evaluated retrospectively during the period 2004–2011; a total of 70 (38%) patients were diagnosed with bloodstream infections. Bacterial etiology was determined, along with their susceptibility patterns. Neutropenia, duration of neutropenia, fever, duration of fever, and C-reactive protein (CRP) were evaluated throughout the study.

Results

A total of 70 patients (38%) were diagnosed with acute leukemias, lymphomas, solid tumors, or brain tumors; those patients experienced 111 episodes of bacteremia. The most common Gram-positive (n=64 [55%]) isolates were Staphylococcus epidermidis (n=26), Staphylococcus hominis (n=9), and Staphylococcus haemolyticus (n=7), and the common Gram-negative (n=52 [45%]) isolates were Klebsiella pneumoniae (n=14), Pseudomonas aeruginosa (n=10), and Escherichia coli (n=7). There was a significant association observed between fever with positive blood culture and different types of cancer (P=0.035). The majority of bacteremia (n=68 [61.3%]) occurred in nonneutropenic episodes. Elevated values of CRP (≥5 mg/L) were detected in 82 (95.3%) episodes and were negatively correlated with absolute neutrophil count (ANC) (r=−0.18; P=0.248) among all cases. However, the infection-related fatality rate was 2.2% (n=4), with three caused by Gram-negative pathogens. Multidrug resistant organisms were implicated in 33 (28.4%) cases and caused three of the mortality cases.

Conclusion

Multidrug resistant organisms cause mortality in pediatric cancer patients. Investigation of antimicrobial susceptibility of these organisms may guide successful antimicrobial therapy and improve the surveillance and quality of pediatric malignancy care.

Acquired aplastic anemia in children

This article provides a practice-based and concise review of the etiology, diagnosis, and management of acquired aplastic anemia in children. Bone marrow transplantation, immunosuppressive therapy, and supportive care are discussed in detail. The aim is to provide the clinician with a better understanding of the disease and to offer guidelines for the management of children with this uncommon yet serious disorder.

Infectious complications in children with severe congenital, autoimmune or idiopathic neutropenia: a retrospective study from the Italian Neutropenia Registry

We describe the incidence and characteristics of infections in children with severe congenital neutropenia (SCN), autoimmune neutropenia (AN) and idiopathic neutropenia (IN). Data extracted from the Italian Neutropenia Registry on 73 patients with 108 episodes of infections were collected from 2000 to 2009. All SCN patients with SCN and one third of AN and IN experienced at least 1 infectious episode, equating to 5.7 infections/patient in SCN and approximately 0.6 in AN and IN. The rate of infections before diagnosis of neutropenia was 6.35/1000 patient-days at risk in SCN, 0.48 in AN and 0.71 in IN (P < 0.001) and significantly decreased after diagnosis. Skin and subcutaneous abscesses and cellulitis were the most frequent types of infection encountered, followed by pneumonia. Infections are an important clinical issue in the management of neutropenic patients, even in those considered at lower risk.