Trends in infection morbidity in a pediatric oncology ward, 1986-1995

Immune System Dysfunction Criteria in Critically Ill Children: The PODIUM Consensus Conference

CONTEXT

Immune system dysfunction is poorly represented in pediatric organ dysfunction definitions.

OBJECTIVE

To evaluate evidence for criteria that define immune system dysfunction in critically ill children and associations with adverse outcomes and develop consensus criteria for the diagnosis of immune system dysfunction in critically ill children.

DATA SOURCES

We conducted electronic searches of PubMed and Embase from January 1992 to January 2020, using medical subject heading terms and text words to define immune system dysfunction and outcomes of interest.

STUDY SELECTION

Studies of critically ill children with an abnormality in leukocyte numbers or function that is currently measurable in the clinical laboratory in which researchers assessed patient-centered outcomes were included. Studies of adults or premature infants, animal studies, reviews and commentaries, case series (≤10 subjects), and studies not published in English with inability to determine eligibility criteria were excluded.

DATA EXTRACTION

Data were abstracted from eligible studies into a standard data extraction form along with risk of bias assessment by a task force member.

RESULTS

We identified the following criteria for immune system dysfunction: (1) peripheral absolute neutrophil count <500 cells/μL, (2) peripheral absolute lymphocyte count <1000 cells/μL, (3) reduction in CD4+ lymphocyte count or percentage of total lymphocytes below age-specific thresholds, (4) monocyte HLA-DR expression <30%, or (5) reduction in ex vivo whole blood lipopolysaccharide-induced TNFα production capacity below manufacturer-provided thresholds.

LIMITATIONS

Many measures of immune system function are currently limited to the research environment.

CONCLUSIONS

We present consensus criteria for the diagnosis of immune system dysfunction in critically ill children.

Which Type of Empiric Antibiotic Therapy is Appropriate? A 20-Year Retrospective Study of Bloodstream Infections in Childhood Cancer

INTRODUCTION

Sufficient empirical antimicrobial therapy in febrile patients with cancer is challenging, owing to the limited arsenal of available antibiotics in an era of growing resistance. Because of the emergence of gram-negative bacteria resistant to ceftazidime and piperacillin, a combination antibiotic therapy was employed that uses meropenem combined with gentamicin and/or vancomycin if the patient further deteriorates.

METHODS

A retrospective cohort analysis was performed including all patients with catheter-associated bloodstream infections (BSIs) and treated for childhood cancer in a tertiary single centre between 1 January 2000 and 31 June 2018. We calculated the prevalence and the risk for BSIs and compared the in vitro susceptibility to various antimicrobial agents.

RESULTS

Of 653 patients with childhood cancer, 113 patients (17.3%) were identified with a total of 139 BSIs, most of them occurring in patients with leukaemia (n = 90, 64.7%) and were associated with gram-positive bacteria (60.5%). In our cohort, all BSIs with gram-negative bacteria exhibited in vitro susceptibility against meropenem alone without any signs of resistance development. The antibiotic coverage of our meropenem-based combination therapy was also highly effective for gram-positive and non-fermenting bacteria. Thus, BSI-related mortality in all 139 BSI episodes was 1.4%. Clostridium difficile infections (CDIs), as main adverse event of carbapenem usage, occurred in only 16 (2.5%) patients.

CONCLUSION

Our meropenem-based combination therapy showed sufficient empirical antibiotic coverage in the majority of BSIs (96.4%) and did not result in an increased rate of unwanted side effects or development of antibiotic resistance.

Antibiotic Susceptibility of Bloodstream Isolates in a Pediatric Oncology Population: The Case for Ongoing Unit-specific Surveillance

Fever in a neutropenic oncology patient requires rapid initiation of effective empiric antibiotics to prevent mortality. We evaluated the appropriateness of our current empiric antibiotic regimen by assessing local antibiotic-susceptibility patterns in our pediatric oncology patients, and comparing them to the general pediatric patterns in our hospital. All blood culture isolates from pediatric oncology patients were reviewed over a 3-year period. Gram-negative and Gram-positive organisms were reviewed separately, with antibiotic susceptibilities for all unique isolates evaluated, and antibiograms generated and compared with general pediatric patients via the Fisher exact test. A total of 84% of Gram negatives were susceptible to meropenem; all resistant organisms were Pseudomonas aeruginosa, with 50% meropenem susceptibility. A total of 91% of Gram negatives were susceptible to cefepime, including 90% of P. aeruginosa and 80% of Escherichia coli. In total, 96% of Gram positives were vancomycin-susceptible; the only resistant organism was a single enterococcal isolate. In comparison with the general pediatric population, significantly fewer pseudomonal isolates were sensitive to meropenem among the oncology population (50% vs. 89%, P=0.0034). As such, in our population, meropenem does not provide adequate monotherapy against Pseudomonas. Ongoing surveillance of antibiotic resistance in this high-risk population is warranted, to ensure appropriate empiric antibiotic usage.

Bloodstream infections in oncology patients at Red Cross War Memorial Children's Hospital, Cape Town, from 2012 to 2014

OBJECTIVES

This study was performed to investigate the epidemiology of bloodstream infection (BSI) in oncology patients at Red Cross War Memorial Children's Hospital (RCWMCH), Cape Town, with focus placed on the most common causes, complications, and antimicrobial susceptibilities in BSI.

METHODS

A retrospective cross-sectional study was conducted in the Haematology-Oncology Unit of RCWMCH. All positive blood cultures from RCWMCH oncology patients obtained in 2012 to 2014 were retrieved to identify cases of BSI.

RESULTS

Three hundred and forty-three positive cultures were identified, for 150 BSI episodes among 89 patients; 49.1% of the culture isolates were Gram-positive bacteria, 41.6% were Gram-negative bacteria, and 9.3% were fungal. Coagulase-negative Staphylococcus and viridans group Streptococcus were the most common Gram-positive isolates. Escherichia coli and Klebsiella species were the most common Gram-negative isolates. The majority of BSI episodes occurred in patients with haematological malignancies (74%), in the presence of severe neutropenia (76.4%), and were associated with chemotherapy (88%). Complications occurred in 14% of BSI. Fungal infections had the highest prevalence of complications (21.4%). Three children died during BSI, giving a case-fatality rate of 2%.

CONCLUSIONS

BSI in these patients was caused mainly by Gram-positive bacteria and was associated with a low case-fatality rate. These results are consistent with worldwide experience of BSI in paediatric oncology.

Minimizing Complications Related to Fever in the Postoperative Pediatric Oncology Patient

Fever is a common postoperative complication that is generally thought to be a benign, self-limiting event. However, for pediatric oncology patients who are often immunocompromised, a postoperative fever may indicate an infection, which can lead to significant complications if not treated promptly. A physical examination, which is an established cost-effective method to rule out infections in the general surgical population, may not be sufficient for oncology patients because clinical symptoms may be atypical or absent in immunocompromised hosts. Although a full septic workup may be unnecessary, additional investigations such as blood cultures may be warranted, and antibiotic therapy should be considered for some or all febrile postoperative cancer patients. No standardized approach to fever management in postoperative oncology patients currently exists, which can present a challenge for those who care for these patients. In the absence of such established practice standards, this article outlines some of the considerations that may be vital in minimizing complications related to fever in the postoperative pediatric oncology patient.

Computed tomography guided percutaneous lung biopsies and suspected fungal infections in pediatric cancer patients

BACKGROUND

The spectrum of potential fungal pathogens known to cause invasive pulmonary infections has grown as a result of intensified immunosuppressive therapy and the emergence of antifungal resistance.

PROCEDURE

In a retrospective single center study, we investigated computed tomography guided percutaneous lung biopsies in 16 childhood patients with suspected fungal infections. Microbiological analysis consisted of microscopic examination, culture, and a broad-range fungal polymerase chain reaction for detection of either Aspergillus or Mucorales species.

RESULTS

In 14 patients (88%), invasive fungal infection with Aspergillus species including A. terreus, Mucormycetes, and Saccharomyces cerevisiae being the main pathogens was confirmed, including patients with a double infection (19%). In two cases, the most likely diagnosis of primary bronchiolitis obliterans organizing pneumonia was established based on the results of typical histopathologic features, negative culture results, and symptoms resolved after treatment with high-dose cortisone. Diagnosis of invasive fungal pneumonia led to an immediate interruption of antineoplastic treatment in 100%, reduction of antibiotic drugs in 76%, and change of empirical to targeted antifungal therapy in 63%. The safety of lung biopsy was guaranteed by lack of any complications, such as bleeding or pneumothorax.

CONCLUSIONS

The increased detection of rare fungal infections by computed tomography guided biopsy supports the need for a rapid and precise diagnosis, as most of the fungal pathogens are at least partially resistant to available antifungal therapy and proper treatment is essential for best practice in patient management.

Antibiotic-resistant Gram-negative bacteremia in pediatric oncology patients--risk factors and outcomes

BACKGROUND

Infection with antibiotic-resistant (AR) Gram-negative (GN) bacteria is associated with increased morbidity and mortality. The aim of this study was to determine risk factors and outcomes associated with GN bacteremia with acquired resistance to antibiotics used in the empiric treatment of febrile neutropenia in pediatric oncology patients at our institution.

METHODS

All episodes of GN bacteremia in oncology patients at the Royal Children's Hospital Melbourne, from 2003 to 2010 were retrospectively reviewed. Information regarding age, diagnosis, phase of treatment, inpatient status, previous AR GN infection, treatment with inotropes or ventilatory support, admission to intensive care unit, and hospital and intensive care unit length of stay were obtained from electronic records.

RESULTS

A total of 280 episodes of GN bacteremia in 210 patients were identified. Of these, 42 episodes in 35 patients were caused by an AR GN organism. Factors independently associated with AR GN bacteremia were high-intensity chemotherapy (odds ratio 3.7, 95% confidence interval: 1.2-11.4), hospital-acquired bacteremia (odds ratio 4.3, 95% confidence interval: 2.0-9.6) and isolation of AR GN bacteria from any site within the preceding 12 months (odds ratio 9.9, 95% confidence interval: 3.8-25.5). Episodes of AR GN bacteremia were associated with longer median hospital length of stay (23.5 days versus 14.0 days; P = 0.0007), longer median intensive care unit length of stay (3.8 days versus 1.6 days; P = 0.02) and a higher rate of invasive ventilation (15% versus 5.2%; P = 0.03). No significant difference in infection-related or all-cause mortality between the 2 groups was identified.

CONCLUSIONS

In pediatric oncology patients, AR GN bacteremia is associated with an increased rate of adverse outcomes and is more likely in patients who have received high-intensity chemotherapy, have been in hospital beyond 48 hours and who have had previous AR GN infection or colonization.

Unchanged antibiotic susceptibility in Escherichia coli and Pseudomonas aeruginosa after long-term in vitro exposure to antineoplastic drugs

BACKGROUND

Certain antineoplastic drugs inhibit bacterial growth. Whether these drugs also cause genetic changes in bacteria that lead to increased antibiotic resistance is not yet documented. Given the massive and repeated antibiotic treatment most cancer patients undergo, this question is important. We have examined the possible effects of in vitro long-term antineoplastic exposure on antibiotic resistance.

METHODS

Using the disc diffusion method, two bacterial strains (Escherichia coli, ATCC 25922, and Pseudomonas aeruginosa, ATCC 27583) were exposed to methotrexate, fluorouracil, vincristine, doxorubicin and cytarabine during 50 overnight cycles. The bacterial strains were susceptibility-tested to several antibiotics before and after repeated exposure to antineoplastics.

RESULTS

No changes in antibiotic susceptibility were seen in the two bacterial strains after long-term exposure to any of the antineoplastic drugs tested.

CONCLUSION

Long-term in vitro antineoplastic exposure did not change the antibiotic susceptibility in the E. coli or P. aeruginosa strains.

Risk factors for infection-related outcomes during induction therapy for childhood acute lymphoblastic leukemia

BACKGROUND

The primary objective was to describe microbiologically documented infections during induction therapy for acute lymphoblastic leukemia. The secondary objectives were to describe risk factors for microbiologically documented infections and for patients with a febrile episode, to identify risk factors for recurrence of fever or reinitiation of antibiotics.

METHODS

This study was a retrospective review of children from 1 to 18 years of age who received induction chemotherapy between March 1997 and September 2006. Microbiologically documented infections were examined through the induction period.

RESULTS

There were 425 children evaluated. The most common pre-existing risk factor for infection was Down syndrome in 11 children. Of the 425 children, 83 (19.5%) experienced at least one microbiologically documented infection. There were 85 infections consisting of 65 bacterial, 15 viral and 5 fungal infections.Variables significantly associated with a microbiologically documented infection were pre-existing risk factors (odds ratio [OR]: 3.63; P = 0.01) and neutropenia at initial infectious episode (OR: 1.86; P = 0.03). Factors associated with recurrence of fever and reinitiation of antibiotics after an initial infectious episode were receipt of a 4-drug induction, neutropenia at the initial infectious episode, initial fever documented in hospital, and lack of bone marrow recovery at the time of initial antibiotic cessation.

CONCLUSIONS

About 20% of children with acute lymphoblastic leukemia have a microbiologically documented infection during induction. Those with pre-existing risk factors and neutropenia at the initial infectious episode were at higher risk of microbiologically documented infection. Continued efforts to refine risk groups may allow for risk-directed prophylactic or empiric strategies.

Vincristine induced peripheral neuropathy potentiated by voriconazole in a patient with previously undiagnosed CMT1X

Peripheral neuropathy is a well-known side effect of vincristine, a micro-tubule inhibitor commonly used to treat malignancies. Severe neurologic adverse events can occur in patients with Charcot-Marie-Tooth disease (CMT) treated with vincristine. Voriconazole is an antifungal agent used increasingly in children with malignancy. Because of its metabolism by hepatic p450 enzymes, voriconazole may inhibit the clearance of many medications, including vincristine. We report a case of vincristine related neuropathy that was exacerbated by voriconazole in a patient with previously undiagnosed, X-linked CMT.

Nosocomial infections among pediatric hematology patients: results of a retrospective incidence study at a pediatric hospital in China

The occurrence of nosocomial infections (NIs) differs in different patient populations and different hospitals, and information on NI in Chinese children patients is scarce. This study fills these research gaps by evaluating the frequency of NIs, main infection sites, and common microorganisms found in pediatric hematology patients in a general children's hospital. A retrospective study was performed by analyzing the medical records of patients with NIs. The rates of NIs were calculated on the basis of cases identified during surveillance and the number of discharges annually. One thousand six hundred and four NIs were detected in 21,456 subjects (overall rate: 7.0 episodes/100 discharges). The most commonly observed infections were respiratory tract infections (1079 cases, 67.3%), followed by gastrointestinal infections (198 cases, 12.3%), skin and soft tissue infections (161 cases, 10.0%), bloodstream infections (97 cases, 6%), and urinary tract infections (16 cases, 1%). Gram-negative bacteria were the most common pathogens, followed by Gram-positive bacteria, virus, and fungal organisms. Respiratory and gastrointestinal infections were the common NIs in pediatric hematology/oncology patients. Gram-negative bacteria were responsible for most pathogens of NIs. In future studies, the prospective use of incidence density rates and postdischarge surveillance in children patient populations would be an interesting research direction.

Neutropenic enterocolitis in children with acute leukemia or aplastic anemia

Neutropenic enterocolitis (NE) and acute appendicitis are life-threatening conditions that develop in children with severe or prolonged neutropenia secondary to acute leukemia and lymphoma. The medical records of 118 patients who were treated for acute lymphoblastic leukemia (69 patients), acute myelogenous leukemia (22 patients), or aplastic anemia (27 patients) between 1997 and 2006 in our hospital pediatric hematology department were examined retrospectively. NE was diagnosed in 11 patients (age range, 2.5-16 years) on the basis of clinical and laboratory features. Two of these 11 patients had appendicitis in addition to NE. Conservative treatment was favored for all patients, but 1 patient with acute appendicitis underwent surgery. Neutropenic patients with a hematologic malignancy and abdominal pain should receive their diagnoses immediately and undergo treatment. NE and acute appendicitis should always be considered in the differential diagnosis of abdominal pain. Conservative treatment must be chosen initially for patients with NE, and these patients should be evaluated carefully for surgery. The criteria for the surgical process are the same as those for immunocompetent children. In addition, the close monitoring of hematologic factors is necessary.

Does the number of exogenous infections increase in paediatric oncology patients when sterile surgical gloves are not worn for accessing Central Venous Access Devices?

The aim of this study was to determine whether the routine use of sterile gloves when accessing central venous catheters (CVCs) affects the incidence of exogenous septicaemia in paediatric oncology patients. The 36-month study period ran prospectively from September 2000 to August 2003. During this time the routine use of sterile gloves for accessing CVCs was suspended. Sterile gloves were only used when obtaining blood samples from the line or injecting substances that required direct entry into the lumen with removal of line cap. Surveillance cultures of throat and rectum were obtained to detect carriage of potential pathogens. Exogenous septicaemia was defined as a blood stream infection due to microorganisms not carried by the patient in throat and/or rectum. The incidence of exogenous septicaemia following a change of practice of not routinely using sterile gloves for accessing lines was compared to the incidence of exogenous septicaemia in a historical control group. The number of exogenous septicaemia episodes per inpatient days with gloves and without gloves was calculated for the total number of episodes and for the first episode for each child. The relative incidence and 95% confidence intervals was also calculated for first and total episodes. For both, all episodes and first episodes there was no statistically significant difference in the incidence of exogenous septicaemia comparing the control and study patients. In summary, this study does not support or approve the use of sterile gloves when accessing CVCs in respect of exogenous septicaemia.

A prospective study of admissions for febrile neutropenia in secondary paediatric units in South East England

BACKGROUND

The Paediatric Oncology Centres (POCs) treating childhood cancer in South East England produce unified supportive care guidelines for use in the secondary pediatric (shared care) units. This study evaluated the adherence to current guidelines for febrile neutropenia (FN) and documented outcome in terms of bacterial isolates, antibiotic resistance patterns, length of hospital stay, and mortality.

PROCEDURE

Prospective study of pediatric FN admissions between July 2001 and December 2002.

RESULTS

Data were received on 433 eligible FN episodes in 212 patients. The recommended empirical antibiotics (piptazobactam + gentamicin) were used in 354 (82%) admissions. Blood cultures were positive in 129 episodes (30%). Gram-positive organisms predominated (120/149 organisms isolated) and the majority were coagulase-negative Staphylococci (95/120). There were 27 Gram-negative isolates and 1 fungal isolate. No Gram-negative isolate was resistant to both first-line antibiotics. Only one death was recorded in the study group. The median length of hospital stay was 5 days.

CONCLUSIONS

We obtained data on a large number of shared care episodes of FN. The antibiotic guidelines were followed in most episodes. Bacteremia was common, but little resistance to first-line antibiotics was documented among Gram-negative isolates, confirming the safety of the strategy in our population.

Infections during induction therapy of childhood acute lymphoblastic leukemia - no association to mannose-binding lectin deficiency

OBJECTIVES

Infection during the induction phase of childhood acute lymphoblastic leukemia (ALL) is a major cause of morbidity and mortality. Several studies have indicated that genetically determined low serum levels of mannose-binding lectin (MBL), a component of innate immunity, are associated with increased risk for infections in patients receiving chemotherapy. Thus, these patients have been proposed to be candidates for MBL replacement therapy.

METHODS

In a population-based cohort of 137 children with ALL treated at a single pediatric hematology-oncology center with an almost identical chemotherapy regimen, we studied the relationship between polymorphisms in the MBL gene (MBL2) and the MBL2 promoter and the risk of infections during the first 50 d of induction therapy.

RESULTS

No increased frequency of infection was seen for the children with genotypes encoding serum low levels of MBL. A higher incidence of fever (P < 0.004), infectious events (P = 0.025), days with neutropenia (P < 0.001) and a higher frequency of antimicrobial therapy (P = 0.0007) were seen in the young age group (<2.5 yr) compared with the older age group (> or =2.5 yr), independent of the MBL genotype.

CONCLUSIONS

MBL deficiency did not influence the frequency of infections in children receiving induction chemotherapy for ALL, not even in the youngest children (<2.5 yr) whom we found to have the highest risk for infections.

Infections in a pediatric patient cohort with acute lymphoblastic leukemia during the entire course of treatment

GOALS

To assess the type, frequency, severity, and outcome of all infectious episodes in a pediatric patient cohort with acute lymphoblastic leukemia (ALL) from a single institution during the entire length of leukemia treatment.

PATIENTS AND METHODS

Eighty-six patients were treated according to a modified ALL Berlin-Frankfurt-Munster protocol. Retrospective analysis of all types of infections according to the treatment phase and the degree of neutropenia is presented.

RESULTS

A total of 610 infectious episodes were recorded. Most infections were documented during maintenance (57%), followed by the induction phase (20.3%). During maintenance, 347 episodes were encountered, with nonspecific viral upper respiratory tract infections (URIs) being the commonest diagnosis (40.0%). Additionally, 38 of 58 total specific viral infections occurred during maintenance: 16 herpes simplex, 7 varicella, 10 herpes zoster infections [varicella-zoster virus (VZV), 45%]. The majority of bacteremia and fever of unknown origin occurred during induction (20%). The number of Gram-negative bacteremia was 50% of the total (26 of 52). The majority of the infections (59.5%) occurred without neutropenia [absolute neutrophil count (ANC) >1,000 microl(-1)]. Fewer infections (9.3%) were recorded with concurrent very severe neutropenia (ANC <100 microl(-1)), although 38.5% of positive blood cultures were documented with severe neutropenia. No infection-related fatality occurred.

CONCLUSIONS

Most of the severe infections occurred during induction. Gram-positive bacteremia and Gram-negative bacteremia were almost equal. URIs were the commonest infections during the entire treatment and during maintenance. Specific viral infections represented a smaller percentage of the total (VZV was the commonest pathogen). Infectious complications represented a significant morbidity factor, but notably, mortality was negligible.

Length of Stay and Mortality Associated With Febrile Neutropenia Among Children With Cancer

Purpose

The aim of this study was to evaluate risk factors for longer length of stay (los) and mortality among hospitalized children with cancer who have febrile neutropenia.

Methods

This study involved analysis of longitudinal data from the University HealthSystem Consortium database from 1995 to 2002. All patients who were 21 years or younger, with diagnostic codes for both neoplastic disease and febrile neutropenia at discharge, were included.

Results

A total of 12,446 patients were identified for the study. The los was 5 days or less for 6,799 patients, and greater than 5 days for 5,647 patients. The mortality rate was 3%. On bivariate analysis, race, age, cancer type, and associated complications (bacteremia/sepsis, hypotension, pneumonia, and fungal infections) were significantly associated with longer length of stay and death. On multivariate analysis, age group, race, cancer type (acute myeloid leukemia, multiple cancers v acute lymphoblastic leukemia), and the complication variables were significantly associated with increased risk of longer los and death. Certain types of cancer (Hodgkin's disease, osteosarcoma/Ewing’s sarcoma, rhabdomyosarcoma, compared with acute lymphoblastic leukemia) and year of discharge after 1995 were significantly associated with a reduced risk of longer length of stay and/or mortality.

Conclusion

Race, age group, year of discharge, associated complications, and cancer type were significantly associated with risk of longer los and mortality. These factors may potentially help in identifying high-risk patients who might benefit from targeted antibiotic therapy or prophylactic hematopoietic growth factor support.

[Bacteraemia risk criteria in the paediatric febrile neutropenic cancer patient]

INTRODUCTION

Cancer patients with febrile neutropenia are not a homogeneous group with respect to risk of bacterial infections. Some authors have proposed that febrile cancer patients with low risk factors of bacteraemia could be managed at home with domiciliary antibiotic treatment. The objectives are: to determine the incidence of bacteraemia in our cancer patients who have febrile neutropenia; and to identify the low-risk factors so that the patients can be managed at home using domiciliary antibiotic treatment.

MATERIAL AND METHODS

Clinical review of paediatric haemato-oncology disease admitted to our hospital in 2002 suffering from febrile neutropenia.

RESULTS

We describe a total of 62 episodes of febrile neutropenia in 30 patients; 24 episodes in haematology patients and 38 episodes in oncology patients. High-risk criteria are age <1 year, poor bone-marrow recovery, chemotherapy within 10 days of the episode, rapid fast neutropenia, leukaemia in relapse, uncontrolled solid cancer, and cardiac or nephrology disease. Based on the number of risk-factors, patients with two or less risk-factors have an incidence of bacteraemia of 6.7% (1/16) and patients with three or more risk factors have an incidence of bacteraemia of 32.6% (15/46); p<0.05.

CONCLUSIONS

Incidence of bacteraemia is similar to the reviewed literature; probability of bacteraemia increases with the number of individual risk factors, and patients with low risk of bacteraemia could be managed on an outpatient basis using domiciliary antibiotic treatment.

Fecal fungal flora of pediatric healthy volunteers and immunosuppressed patients

Most hematogenous candidiasis originates from endogeneous host flora. Fungal flora of gastrointestinal system are important source of infection especially in immunosupressed patients. The purpose of this study was to investigate the fecal fungal flora of pediatric patients with hematologic malignancy or disorders and to compare the results with healthy volunteers. For this purpose, fungal etiological agents were investigated retrospectively in stool samples of 80 patients followed in Bone marrow transplantation and Hematology-Oncology units. The diagnosis of patients were as follows: 26 acute myelogeneous leukemia, 19 acute lymphocytic leukemia, 5 lymphoma, 3 chronic myelogeneous leukemia, 2 solid tumor, 4 neuroblastoma and 21 hematologic disorders. In patients, totally 102 fungal growth was detected and 42 (41.2%) C. albicans and 51 (50%) non-albicans Candida species and 9 (8.8%) yeast other than Candida and mould was isolated. The results were compared prospectively with growth in stool samples of 61 healthy children. C. albicans was detected in 16 (43.2%) and non-albicans Candida species in 15 (40.5%) and yeasts other than Candida and mould in 6 (16.2%) of 37 fungal growth in controls. Non-albicans Candida species growth was found significantly higher and C. glabrata was more prevelant in patients than in controls (p < 0.001).

A prospective study of septicaemia on a paediatric oncology unit: A three-year experience at The Royal Liverpool Children’s Hospital, Alder Hey, UK

Septicaemia in neutropaenic patients is predominantly due to gut translocation [endogenous septicaemia] and contamination of the central venous catheter by microorganisms not carried by the patient [exogenous septicaemia]. To control both types of infection, a protocol was implemented based on pre 1990's parenteral and enteral antimicrobials together with strict hygiene. Surveillance cultures of throat/rectum were taken to distinguish exogenous from endogenous septicaemia and enteral non-absorbable antibiotics are administered as part of selective decontamination of the digestive tract (SDD). This protocol was evaluated in a 14-bedded paediatric oncology unit over a period of 3 years. 313 Septicaemia episodes were recorded in 131 children. 28.4% of the septicaemias were caused by microorganisms associated with the unit, equivalent to 0.82 episodes per 100 patient days. Low-level pathogens such as coagulase-negative staphylococci caused more than 70% of infections. Amongst the potential pathogens, Pseudomonas species (7.8%) and Staphylococcus aureus (5.5%) were predominant. Antibiotic resistance was rare with no superinfections or outbreaks. Four patients (3%) died, two due to Candida species and two due to Pseudomonas aeruginosa. We believe that the addition of enteral non-absorbable antibiotics to systemic antibiotics maintained a low level of resistance and mortality but a randomised controlled trial is indicated to confirm these observations.

Bloodstream infections and invasive mycoses in children undergoing acute leukaemia treatment: A 13-year experience at a single Italian institution

The incidence rate (IR) of bloodstream infections (BI) and invasive mycoses (IM) during chemotherapy for paediatric acute lymphoblastic (ALL) or non-lymphoblastic leukaemias (AnLL) was evaluated for 153 BI and 22 IM diagnosed during 143,668 patient-days at risk from January 1988 to December 2000. IR, the number of episodes/100 days at risk, was 0.315 for AnLL and 0.092 for ALL (P < 0.001) with significant changes reflecting the intensity of anti-ALL chemotherapy. IR was 0.097 for first-line less intensive, 0.136 during first-line intensive, 0.261 during second-line therapy (P < 0.001), and 0.021 during maintenance. During intensive chemotherapy, the IR for BI was 0.134 in ALL with 0.087 for first-line less intensive therapy, 0.110 for first-line intensive, 0.230 for second-line intensive therapy (P < 0.001) and 0.274 in AnLL (P = 0.001). IR was 0.021 in ALL and 0.048 in AnLL (P = 0.034) for IM. In conclusion, there is a correlation between intensity of chemotherapy and rate of infections in paediatric acute leukaemias.

Microbiological spectrum and susceptibility patterns of pathogens causing bacteraemia in paediatric febrile neutropenic oncology patients: comparison between two consecutive time periods with use of different antibiotic treatment protocols

This study was devised to look at trends in the microbiological spectrum and susceptibility patterns of pathogens causing bacteraemia in paediatric febrile oncology patients. The retrospective study compared various microbiological aspects recorded for febrile oncology neutropenic patients treated with two different empirical antibiotic regimens (ceftazidime plus gentamicin during 1998-1999 and piperacillin/tazobactam plus amikacin during 2000-2002). Eighty-one bacteraemic episodes occurred in 41 patients. Overall, 132 (34 during 1998-1999 and 98 during 2000-2002) organisms were isolated: 84 (65%) Gram-negative bacteria, 39 (30%) Gram-positive bacteria and 7 (5%) fungi. Enterobacter spp. incidence decreased from 18 to 6% (P=0.07) while the recovery rates of Gram-positive organisms increased from 24 to 32% (P=0.4) during 2000-2002 compared with 1998-1999. MRSA were not isolated from any episode of bacteraemia. Five (18%) of the 28 Escherichia coli and Klebsiella spp. isolates were beta-lactamase producers (80% [4/5] isolated during 2000-2002). Twenty-seven of 28, 27/27, 23/28, 20/25 and 27/28 of these isolates were susceptible to imipenem, piperacillin/tazobactam, gentamicin, ceftazidime and ciprofloxacin, respectively. Thirty-two of 34 (94%) and 60/74 (81%) of the Gram-negative organisms isolated during 2000-2002 were susceptible to piperacillin/tazobactam and ceftazidime, respectively (P=0.076). No major differences in the microbial spectrum and antibiotic susceptibilities were recorded between the two consecutive study periods. An increase in the number of extended beta-lactamase producing E. coli and Klebsiella spp. occurred during 2000-2002. All beta-lactamase producing organisms were susceptible to piperacillin/tazobactam and initial empirical therapy with piperacillin/tazobactam was more appropriate than ceftazidime to cover most of the pathogens causing bacteraemia.

Meropenem in the treatment of febrile neutropenic children

The aim of this retrospective study was to evaluate the clinical effectiveness of meropenem in immunocompromised children. Between January 1998 and December 2002 in the hemato-oncological units of our hospital meropenem was used in 87 febrile events diagnosed in 55 patients, and 328 bacterial cultures were evaluated. Microorganisms were detected and identified in 64 of the 328 hemocultures; there was a predominance of gram-positive strains (67%). In 49.4% the infection was documented microbiologically. In 16 additional cases the infection was proven clinically and 32.2% of the episodes were considered to be fever of unknown origin. The success rate of the meropenem therapy-excluding the proven fungal or coagulase-negative Staphylococcus infections--was 72.9% and for the whole cohort 49.4%. The results demonstrate that meropenem is effective and well-tolerated when used for the treatment of neutropenic cancer children.

Myositis complicating viridans streptococcal sepsis in childhood leukemia

Hematogenous focal infections are a rare complication of bacteremia or sepsis caused by viridans-group streptococci. We describe two patients with acute leukemia who developed myositis during alpha-hemolytic streptococcal bacteremia. Children complaining of severe muscle pain associated with viridans streptococcal infections should be carefully evaluated for the presence of focal pyogenic complications and rhabdomyolysis. The severity of infectious myositis is highly variable, depending on the etiologic organism and host immunity, making individualized treatment the most effective approach.

Fever in neutropenia in children and adolescents: Evolution over time of main characteristics in a single center, 1993?2001

GOALS OF WORK

To assess the evolution over time of main characteristics of episodes of fever in severe chemotherapy-induced neutropenia (FN) in children and adolescents with cancer treated for FN following nonmyeloablative chemotherapy, to compare the results with the experiences of other centers, and to assess the impact of the changes found on management of FN and on risk prediction rules.

PATIENTS AND METHODS

Retrospective cohort study of all children and adolescents up to 18 years presenting with FN in a single pediatric oncology unit between 1993 and 2001.

MAIN RESULTS

In 132 patients, 364 episodes of FN were reported. The relative incidence of FN increased significantly over time in patients with precursor B-cell acute lymphoblastic leukemia (PBC-ALL), reflecting the increased intensity of chemotherapy. At presentation with FN, the proportions of patients (1) with PBC-ALL versus other malignancies, (2) with other malignancies being in complete remission, (3) with a central venous catheter, and (4) with shaking chills all significantly increased over time (overall proportions, 64%, 60%, 50%, and 5%, respectively; p <0.001 for all). In 337 (93%) episodes, ceftriaxone plus amikacin was used as empirical broad spectrum antimicrobial therapy.

CONCLUSIONS

This study demonstrates that some characteristics of FN, though not necessarily its management, change over time, implying regular update of risk prediction rules. In contrast to other centers, the first-line antimicrobial therapy did not need modification because of changing resistance patterns.

[Cefepime-amikacin combination in febrile neutropenic children with malignant hemopathy or tumor]

Our aim was to evaluate retrospectively the efficacy of a therapeutic strategy with a first line combination based on cefepime-amikacin in febrile neutropenic children treated with chemotherapy.

PATIENTS AND METHODS

Sixty-five neutropenic febrile episodes in 43 children treated by the association cefepime-amikacin, were evaluated according to the clinical status, the depth and duration of neutropenia, the underlying disease and the initial treatment.

RESULTS

Thirty-nine (60%) episodes were successfully treated by the association cefepime-amikacin. Among the 26 persisting febrile episodes, adjunction of vancomycin and amphotericin B was effective in 11 (76% of total rate success) and 5 (84% of total rate success) cases respectively. The efficacy of the first line antibiotherapy was not different as regards to the duration and the depth of neutropenia. Otherwise, febrile episodes after chemotherapy against solid tumours were rapidly controlled by the first and second line of the anti-microbial strategy. Children treated for haematological malignancies presented a lower response rate (P = 0.03).

CONCLUSION

In febrile and neutropenic children treated with chemotherapy, the association cefepime-amikacin appeared to be a safe empirical treatment. In a neutropenic child, the immunodeficiency and possibly the clinical status should be the major factors of the infectious prognosis more than the duration of aplasia.

The role of Clostridium difficile and viruses as causes of nosocomial diarrhea in children

OBJECTIVE

We report surveillance of nosocomial diarrhea in children at our institution during the past decade and note different epidemiology of diarrhea due to viruses and Clostridium difficile.

DESIGN

A prospective cohort study.

SETTING

A university-affiliated pediatric hospital with 180 beds serving an urban area and providing referral care for the Maritime Provinces of Canada.

PARTICIPANTS

Children younger than 18 years.

METHODS

Surveillance was conducted from 1991 to 1999 using personal contact with personnel and review of microbiology and medical records. Nosocomial diarrhea was defined as loose stools occurring more than 48 hours after admission, with at least two loose stools in 12 hours and no likely non-infectious cause.

RESULTS

Nosocomial diarrhea was the third most common nosocomial infection (217 of 1,466; 15%), after bloodstream and respiratory infections, with from 0.5 to 1 episode per 1,000 patient-days. Of 217 nosocomial diarrhea episodes, 122 (56%) had identified pathogens: C. difficile (39 of 122; 32%), rotavirus (38 of 122; 31%), adenovirus (36 of 122; 30%), and other viral (9 of 122; 7%). The median age was 1.3 years (range, 11 days to 17.9 years), 0.80 year for children with viral diarrhea, 3.9 years for children with C. difficile, and 1.5 years for children with diarrhea without a causative organism identified (P< .0001). Most children with nosocomial diarrhea were incontinent (diapered) at the time of their first episode (138 of 185; 75%), but preexisting incontinence was more common in those with viral diarrhea (93%) compared with those with no organism identified (71%) or those with C. difficile-associated diarrhea (CDAD) (49%) (P <.0001).

CONCLUSIONS

C. difficile is the single most common cause of nosocomial diarrhea in our tertiary-care center, although all viral pathogens account for 69% of cases. Diapered status appears to be a risk factor for CDAD in children, and CDAD occurs more often in older children than viral nosocomial diarrhea. Further characterization of risk factors for, and morbidity associated with, nosocomial CDAD in children is warranted.

Evolving concepts of management of febrile neutropenia in children with cancer

BACKGROUND

Recent investigations of febrile neutropenia in pediatric cancer patients have identified subsets of low-risk patients who can be managed with less antibiotic therapy than previously recommended standards.

METHODS AND MATERIALS

PubMed and Medline were searched for prospective trials and reviews of febrile neutropenia in children. Magnitude and duration of fever and neutropenia, comorbidities, and therapeutic strategies were examined.

RESULTS

Twenty-seven prospective trials and five reviews were identified. The child with cancer and low-risk febrile neutropenia is clinically well and afebrile within 24-96 hr of antibiotic therapy and has evidence of marrow recovery with a rising phagocyte count. Disqualifying comorbidities include leukemia at diagnosis or in relapse, uncontrolled cancer, age under 1 year, medical condition(s) that would otherwise require hospitalization and social or economic conditions that may potentially compromise access to care or compliance. Therapeutic strategies include parenteral or oral antibiotics in the hospital with early discharge or parenteral antibiotics in the outpatient setting followed by oral or parenteral therapy and daily reassessment. Although as many as 25% of low-risk patients require modification of therapy and/or hospitalization, life-threatening or fatal infection is exceptional.

CONCLUSION

One-third to one-half the children with febrile neutropenia are at low-risk of serious infection. In the context of clinic trials, they can be safely managed with inpatient or outpatient strategies that maintain close follow-up and reduce the burden of antibiotic therapy. Adoption of these alternative strategies as the standard of care should proceed with caution guided by written protocols.

Evaluation of risk prediction criteria for episodes of febrile neutropenia in children with cancer

PURPOSE

To evaluate the feasibility of risk stratification of children with cancer and febrile neutropenia using a simple set of criteria from data available to the clinician at the time of the patient's presentation.

PATIENTS AND METHODS

This study is a retrospective cohort study of all children with cancer admitted to a single institution with fever and neutropenia (defined as an absolute neutrophil count < 500 cells/mm3) in a 1-year period. Patients were defined a priori as low risk if they were outpatients at the time of presentation with febrile neutropenia, had an anticipated duration of neutropenia less than 7 days, and had no significant comorbidity. All others were considered high risk. Data was analyzed by first admission for each patient and secondarily for all admissions for febrile neutropenia.

RESULTS

There were 188 admissions in 104 patients for febrile neutropenia during the study period. Of these 47% were high risk and 53% were low risk. The duration of fever was not significantly different in the two groups. However, the duration of neutropenia and the length of hospital stay were significantly longer in the high-risk group. The frequency of bacteremia, other documented infection, and serious medical complications was significantly different in the two groups. Overall, the rate of any adverse event was 4% in the low-risk group versus 41% in the high-risk group.

CONCLUSIONS

Simple criteria available to the clinician at the time of evaluation of the child with cancer who has fever and neutropenia allow the selection of a population at low risk for bacteremia or serious medical complication. A prospective study is planned using these risk criteria, evaluating outpatient oral antibiotic therapy in low-risk children with cancer.

Incidence of septicaemias and invasive mycoses in children undergoing treatment for solid tumours: a 12-year experience at a single Italian institution

We carried out a retrospective study on the infection rate--in episodes per 100 person months at risk (p/m/r)--of septicaemia and invasive mycoses in children with solid tumours treated at a single institution between 1985 and 1996. Among 982 patients, accounting for 8108 p/m/r, 257 infectious episodes were documented, for an infection rate of 3.2. The infection rate for "intensive" treatment was greater than that for "less intensive" treatments, 3.7 compared with 0.5, respectively; P<0.001. 58% of infectious episodes were associated with neutropenia, 22% were megatherapy-related, and 39% were related to central venous catheter (CVC), while in 13% of the episodes no risk factor was identified. Of the episodes, single organism Gram-positive bacteraemias accounted for 62%, single organism Gram-negative for 23%, multiple organism bacteraemias for 7%, invasive mycoses for 4%, and isolated fungaemias for 4%. The infection rate for Gram-positive organisms decreased significantly over time (-5.9% per year; P<0.01), but increased for the Gram-negative organisms (+3.4% per year; P=0.4). This study demonstrates that the risk of bacteraemia increases in parallel with the treatment intensity, and that a considerable number of children with solid tumours develop bacteraemia in the absence of an identifiable risk factor.