Efficacy and safety of withholding antimicrobial therapy in children with cancer, fever, and neutropenia, with a demonstrated viral respiratory infection: a randomized clinical trial

OBJECTIVES

To validate the efficacy and safety of withholding antimicrobial therapy in a new cohort of children with cancer and febrile neutropenia (FN) having a demonstrated viral respiratory tract infection.

METHODS

Prospective, multicenter, noninferiority, randomized study, approved by the ethical committee, in children presenting with FN at seven hospitals in Chile, evaluated at admission for diagnosis of bacterial and viral pathogens. Children who were positive for a respiratory virus, negative for a bacterial pathogen, and had a favourable evolution after 48-72 hours of antimicrobial therapy were randomized to either maintain or withhold antimicrobial therapy. The primary endpoint was the percentage of episodes with an uneventful resolution, whereas the secondary endpoints were days of fever, days of hospitalization, requirement of antimicrobial treatment readministration, sepsis, paediatric intensive care unit admission, and death.

RESULTS

A total of 301 of 939 children with FN episodes recruited between March 2021 and December 2023 had a respiratory virus as a unique identified microorganism, of which 139 had a favourable evolution at 48-72 hours and were randomized, 70 to maintain and 69 to withdraw antimicrobial therapy. The median days of antimicrobial therapy was 5 (IQR 3-6) versus 3 (IQR 3-6) days (p < 0.001), with similar frequency of uneventful resolution 66/70 (94%) and 66/69 (96%); relative risk, 1.01; (95% CI, 0.93 to 1.09), absolute risk difference 0.01; (95% CI, -0.05 to 0.08) and similar number of days of fever and days of hospitalization. No cases of sepsis, paediatric intensive care unit admission, or death were reported.

DISCUSSION

We validated the strategy of withdrawal antimicrobial therapy in children with FN and viral respiratory tract infection based on clinical and microbiological/molecular diagnostic criteria. This will enable advances in antimicrobial stewardship strategies with a possible future impact on antimicrobial resistance.

Cytokine and chemokine profiles in episodes of persistent high-risk febrile neutropenia in children with cancer

BACKGROUND

In children with cancer and persistent high-risk febrile neutropenia (HRFN), cytokines/chemokines profiles can guide the differentiation of febrile neutropenia (FN) due to infections and episodes of unknown origin (FN-UO).

METHODS

A prospective, multicenter study in Santiago, Chile included patients ≤ 18 years with cancer and HRFN. Clinical and microbiological studies were performed according to validated protocols. Serum levels of 38 cytokines/chemokines were determined on day 4 of persistent HRFN. We performed comparisons between i) HRFN episodes with a detected etiological agent (FN-DEA) and FN-UO, and ii) bacterial versus viral infections. ROC curves were used to assess the discriminatory power of the analytes.

RESULTS

110 HRFN episodes were enrolled (median age 8 years, 53% female). Eighty-four patients were FN-DEA: 44 bacterial, 32 viral, and 8 fungal infections. Twenty-six cases were categorized as FN-UO. Both groups presented similar clinical and laboratory characteristics. Nineteen out of 38 analytes had higher concentrations in the FN-DEA versus FN-UO group. G-CSF, IL-6, and Flt-3L showed the highest discriminatory power to detect infection (AUC 0.763, 0.741, 0.701). Serum levels of G-CSF differentiated bacterial infections and IP-10 viral agents. A combination of G-CSF, IL-6, Flt-3L, and IP-10 showed an AUC of 0.839, 75% sensitivity, and 81% specificity.

CONCLUSION

A specific immune response is present on day four of persistent HRFN in children with cancer. We propose a combined measure of serum concentrations of G-CSF, IL-6, IP-10, and Flt-3L, in order to predict the presence of an infectious agent as compared to an episode of FN with unknown origin.

Usefulness of serum galactomannan in initiating and modifying antifungal therapy in children with cancer and persistent high-risk febrile neutropenia

BACKGROUND

Invasive fungal disease is a major cause of morbidity and mortality in children with cancer and high-risk febrile neutropenia (HRFN). Repeated serum galactomannan (sGM) measurements have been described as an effective tool to guide therapy in adults under suspicion of invasive aspergillosis. However, the utility of this approach has not been reported in paediatric population.

OBJECTIVES

To evaluate the usefulness of sGM measurements in initiating and modifying antifungal therapy (AFT) in children with cancer and persistent HRFN.

PATIENTS/METHODS

Nested case-control study in children with cancer and persistent HRFN episodes, between July 2013 and January 2019. Patients were classified as cases and controls depending on if they received AFT or not, respectively. Through odds ratio analysis, we assessed the role of sGM positivity in the AFT initiation decision. Then, we analysed the group of patients that initiated AFT, and compared those who had AFT modifications and those who did not, analysing different sGM kinetics thresholds.

RESULTS

A total of 191 episodes from children with persistent HRFN were enrolled, of which 107 received AFT and 84 did not. The median age was 7 years (IQR 4-12), 52% were male and 89% had a haematologic malignancy as underlying disease. Positive sGM was not associated with AFT initiation (OR 0.99, 95% CI 0.43-2.33, P = .99). A difference threshold in sGM Δ ≥ 0.3 sGM was significantly associated with AFT modification (OR 5.07, 95% CI 1.02- 25.70, P = .04).

CONCLUSIONS

Our results suggest the utility of serial sGM sampling during AFT in children with persistent HRFN.

[Consensus of infectious complications in patients treated with selected biological therapies: first Part]

The use of biological therapies has meant a great improvement in the management of several conditions like autoimmune, neoplastic or others diseases. Although its use has implied significant improvements in the prognosis of these diseases, it is not exempt from complications: infectious diseases as one of them. The objective of this consensus was to evaluate, from an infectious viewpoint, the safeness of the most frequently used biological therapies and give recommendations for the prevention of infections in patients treated with these drugs. These recommendations were based on the highest quality evidence available for the selected biologics. The consensus counts of two manuscripts. This first part details the risks of developing infectious complications depending on the type of biological used for a certain pathology. This evaluation included a broad search in MEDLINE and Epistemonikos of systematic reviews and meta-analyzes of controlled clinical trials and casecontrol examining post-treatment infections with anti-TNF alpha, anti-CD20, anti-CD52, CTLA4-Ig and anti-integrins. The research was complemented by a review of: multicentre cohorts of biological users, the MMWR of the CDC, Atlanta, U.S.A., and national registers and scientific societies in which infectious complications derived from the use of biological therapies were mentioned.

Chemometric assessment of soil organic matter storage and quality from humic acid infrared spectra

The knowledge of biogeochemical mechanisms involved in soil organic carbon (SOC) storage is crucial to control its release to the atmosphere. In particular, the chemical composition of soil organic matter (SOM) plays an important role in the performance of the C storage and resilience in soils. The structural information provided by infrared spectroscopy (IR) of soil humic acid (HA) was used in the assessment of the C storage potential of 35 Spanish soils. Partial least squares (PLS) regression using the intensities of the points of the IR spectra of the HAs (4000-400 cm^-1) as descriptors shows that a relationship exists between IR spectral pattern and the SOC content. This was also the case for E4 (humification index based on HA optical density at 465 nm). In addition, the chemical characteristics of the HAs correlated with the SOC levels were identified from digital data treatments of the IR spectra. Additional application of principal component analysis (PCA) and multidimensional scaling (MDS) suggested that bands assigned to carboxyl and amide structures were characteristic in HAs from soils with low C content, whereas HA spectra from soils with high C levels showed a conspicuous band pattern suggesting structural units of lignin from slightly transformed plant residues. The spectral profiles were analyzed in detail by an approach based on digital subtraction of IR spectra obtained by averaging those from HAs extracted from soils in the upper and lower quartiles of the SOC distribution. The results showed that significant relationships exist between the molecular composition of HAs and SOC levels and E4 values in a way in which aromatic, carboxyl and amide groups were predominant in HAs from soils with low SOC content, whereas lignin-derived structures were more characteristic of HAs from soils with high SOC content.

[Evaluation of bone mineral density in children with vertical infection by HIV]

Changes in bone mineral density (BMD) are common in adults infected with human immunodeficiency virus (HIV). There are few studies evaluating bone involvement in children infected.

OBJECTIVE

To evaluate BMD in vertically HIV-infected children.

METHODS

We studied 53 infected children (8-18 years) from five hospitals. Disease status, nutritional assessment, vitamin D (25-OHD) levels and immunological status were recorded. BMD was measured by densitometry. Descriptive analysis, comparison of means and simple and multiple linear regression were used.

RESULTS

88.7% children were in stage B and C, 57% were eutrophic and 18.9% had short stature. 33.3% had 25-OHD levels < 20 ng / ml. 11%, 6% and 4% of the children had BMD <-2DE in hip, spine and whole body respectively. BMD was correlated with BMI, height, disease stage and years of treatment. Only protease inhibitors (PIs) maintained their significance when adjusted for other variables.

CONCLUSION

children infected with HIV had lower BMD by age compared to NHANES III data. The severity of the disease, height, zBMI, years of treatment with antiretrovirals, mainly IP, are related to the reduction of bone mass.

Multi-Target Strategy for Pan/Foot-and-Mouth Disease Virus (FMDV) Detection: A Combination of Sequences Analysis, in Silico Predictions and Laboratory Diagnostic Evaluation

Foot-and-mouth disease (FMD) is a highly contagious viral disease affecting cloven-hoofed animals that causes severe economic losses. The disease is characterized by a vesicular condition and it cannot be differentiated from other vesicular diseases. Therefore, laboratory confirmation of any suspected FMD case is compulsory. Despite viral isolation in cell cultures has been considered for many years as the gold standard for FMD diagnosis, the advantages of real-time reverse transcription polymerase chain reaction (rRT-PCR) technology have motivated its use directly in clinical specimens for FMD diagnosis. The current work was aimed to develop and validate a molecular multi-check strategy using rRT-PCR (mMulti-rRT-PCR) based on SYBR-Green I for pan/foot-and-mouth disease virus (pan/FMDV) diagnosis. From in silico approaches, different primer pairs previously reported were selected and modified to reduce the likelihood of viral escape as well as potential failures in the pan/FMDV detection. The analytical parameters were evaluated using a high number of representative viral strains. The repeatability of the assay and its performance on field samples were also assessed. The mMulti-rRT-PCR was able to detect emergent FMDV strains that circulated in South America between the years 2006–2010 and on which the single rRT-PCRs failed when they were applied independently. The results obtained here showed that the proposed system is an accurate and rapid diagnosis method for sensitive and specific detection of FMDV. Thus, a validated mMulti-rRT-PCR assay based on SYBR-Green I detection coupled to melting curves resolution for pan/FMDV diagnosis on clinical samples is proposed. This study also highlights the need to incorporate the multi-target detection principle in the diagnosis of highly variable agents, specially, of those listed by OIE like FMDV.

[Young women with HIV infection acquired by vertical transmission: Expectations of having uninfected children]

INTRODUCTION

Pediatric antiretroviral therapy (ART), changed the prognosis of the disease, allowing young women infected by vertical transmission (TV) to be pregnant without risk for their fetus of acquiring this infection.

AIM

To describe the clinical-immune status in pregnant women that acquired HV by vertical transmission, treatments received, monitoring of pregnancy and newborn characteristics.

MATERIAL AND METHODS

A protocol was performed, evaluating clinical and immunological parameters during pregnancy, ART used, protocol preventing vertical transmission (PPTV), and follow up of children to 18 months of age.

RESULTS

Of 358 HIV-positive patients vertically infected, five women became pregnant, between 14 and 24 years old. Pregnancies were controlled in clinical/immune-stage N2 C3. They had received two to five therapies. Full PPTV was performed in all binomials. Pre-natal undetectable viral loads ranged from 4,700 ARN copies/mL. Five living children were born by Caesarean section, four of them with 37 weeks of completed gestation and one of them with 34 weeks of gestation. All received zidovudine (AZT) for 6 weeks. CD4 at 72 hours of life ranged from 48% to 74.6%. All children were born uninfected with HIV. Only two had mild anemia.

CONCLUSIONS

Expectations of HIV mothers vertically infected to have healthy children are similar to those infected by horizontal transmission, using PPTV.

[HIV/AIDS infection in children and adolescents: Chilean cohort 1987-2014]

The present document describes the Cohort of HIV/AIDS children detected in Chile from 1987 to August 2014 and the effectiveness of the Protocol for Prevention of Vertical Transmission (PPVT) of HIV infection. Of the 375 HIV infected children enrolled since 1987 to August 2014, 245 of them are still in pediatric control. From the analysis of the Cohort is inferred that: a) it has observed an improvement in the detection of the HIV infected child, in number and precocious time; b) the majority of these children continue to be detected by clinic symptoms and signs (mainly unspecific and infectious manifestations); c) the ARVT use has meant a clinic and immunologic improvement with diminution of the infections, principally opportunistic infections, with a better life quality, a prolongation of survival and a diminution of lethality; d) as more survival has been produced, cancer has begun to be detected, a very infrequent complication observed in them before the ARVT use. The PPVT started in 1995, and was reinforced in 2005 with the "Joint Norm of HIV and Syphilis Vertical Transmission Prevention" (MINSAL), both have meant a diminution of the HIV vertical transmission from > 35% (before 1995) to < 2% nowadays in the mother-child binomial; also have permitted a second generation of HIV exposed children born without infection. In spite this PPVT, still HIV infected child continue to be detected which imply failures in some points of the health system.

[Incidence of cancer in Chilean HIV-infected children]

BACKGROUND

Pediatric HIV (+) patients have a 100 times greater risk of cancer than HIV (-) children.

OBJECTIVE

To describe in Chilean HIV (+) children, cancer types, its appearance in relation to the stages of HIV disease and mortality.

METHODS

A protocol was created to know some characteristics of these patients from the point of view of their HIV infection and cancer pathology.

RESULTS

Of 360 HIV (+) children confirmed by the Institute of Public Health to May 2014, 9 patients with neoplastic disease (2.5%) were diagnosed. All the children were on ART, had more than three years of evolution of HIV infection and were in moderate to severe clinical/immunological stages. Lymphoma was the most common cancer. Five children, has received therapy according to Programa Infantil Nacional de Drogas Antineoplásicas (PINDA). There was no interaction between cancer treatment and antiretroviral therapy. Mortality was 13.8 x 1000 (5 cases).

CONCLUSIONS

The incidence and type of neoplasia is consistent with the international literature, with less survival than HIV (+) children without tumors. The occurrence of cancer was observed in children with moderate to severe clinical and immunological compromise.

[Prophylaxis against respiratory viral disease in pediatric and adult patients undergoing solid organ and hematopoietic stem cells transplantation]

Respiratory viruses have been identified as a cause of morbidity and mortality in patients undergoing SOT and HSCT, specially in children. The most frequent are respiratory syncytial virus (RSV), influenza (FLU), parainfluenza (PI) and adenovirus (ADV). These infections are associated with progression to severe lower respiratory tract infections in up to 60% of the cases. It is advised to apply universal protection recommendations for respiratory viruses (A2) and some specific measures for FLU and AD. FLU: Annual anti-influenza vaccination (from 4-6 months post-transplantation in SOT, 6 months in HSCT (A2)); post- exposure prophylaxis in FLU (oseltamivir for 10 days (B2)). In lung transplantion, the prophylaxis should last as long as the risk period (B2). ADV: There is no vaccine nor valid chemoprophylaxis strategy to prevent ADV disease. In some specific HSCT recipients, weekly PCR monitoring is recommended until day+100 (A3).

[Bloodstream infections in children with cancer and high risk fever and neutropenia episodes in six hospitals of Santiago, Chile between 2004 and 2009]

INTRODUCTION

To determine the etiology of invasive bacterial infection in high risk febrile neutropenia (HRFN) episodes in children with cancer is essential because of the favorable impact on mortality of the early empiric antibiotic treatment.

OBJECTIVE

To determine the etiology of bacteremia in pediatric patients with cancer and HRFN in the National Child Program of Antineoplastic Drugs during the 2004-2009 period, and compare these agents and their antimicrobial susceptibility with the period 1994-1998 described in a previous study.

METHODS

The causative agents of bacteremia were prospectively recorded in patients less than 18 years of age receiving chemotherapy for cancer with HRFN and positive blood cultures admitted to one of the six hospitals from the Child Program of Antineoplastic Drugs network during the period 2004-2009.

RESULTS

839 episodes of HRFN were identified; 181 blood cultures were positive in the following proportion: gram positive cocci (56%), gram negative bacilli (42%) and yeast (2%).The most common etiologic agents were Staphylococcus coagulase negative (25%), Escherichia. coli (20%), group viridans Streptococcus (14%), Staphylococcus aureus (13%) and Pseudomonas aeruginosa (9%). Comparing the two periods, the relative frequency of Streptococcus spp increased from 4 to 17%, coagulase negative Staphylococcus decreased from 44 to 25%, showing an increase in their resistance to oxacillin from 55% to 77%.

CONCLUSIONS

We describe the main etiological agents from HRFN episodes in children with cancer in a 5 years period. This information could help for a better approach in the empirical antimicrobial therapy in this population.