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

Invasive Fusarium solani infection diagnosed by traditional microbial detection methods and metagenomic next-generation sequencing in a pediatric patient: a case report and literature review

Fusarium solani, as an opportunistic pathogen, can infect individuals with immunosuppression, neutropenia, hematopoietic stem cell transplantation (HSCT), or other high-risk factors, leading to invasive or localized infections. Particularly in patients following allogeneic HSCT, Fusarium solani is more likely to cause invasive or disseminated infections. This study focuses on a pediatric patient who underwent HSCT for severe aplastic anemia. Although initial blood cultures were negative, an abnormality was detected in the 1,3-β-D-glucan test (G test) post-transplantation. To determine the causative agent, blood samples were subjected to metagenomic next-generation sequencing (mNGS) and blood cultures simultaneously. Surprisingly, the results of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and mNGS differed slightly, with mNGS identifying Nectria haematonectria, while MALDI-TOF MS based on culture showed Fusarium solani. To clarify the results, Sanger sequencing was performed for further detection, and the results were consistent with those of MALDI-TOF MS. Since the accuracy of Sanger sequencing is higher than that of mNGS, the diagnosis was revised to invasive Fusarium solani infection. With advancements in technology, various detection methods for invasive fungi have been developed in recent years, such as mNGS, which has high sensitivity. While traditional methods may be time-consuming, they are important due to their high specificity. Therefore, in clinical practice, it is essential to utilize both traditional and novel detection methods in a complementary manner to enhance the diagnosis of invasive fungal infections.

Enhancing prognostic prediction of invasive candidiasis among cancer patients with a serum C5a-based scoring model

PURPOSE

Invasive candidiasis poses a life-threatening risk, and early prognosis assessment is vital for timely interventions to reduce mortality. Serum C5a levels have recently been linked to prognosis, but confirmation in cancer patients is pending.

METHODS

We detected the concentrations of serum C5a in hospitalized cancer patients with invasive candidiasis from 2020 to 2023, and retrospectively analyzed the clinical data.

RESULTS

372 cases were included in this study, with a 90-day mortality rate of 21.8%. Candida albicans (48.7%) remained the predominant pathogen, followed by Candida glabrata (25.5%), Candida tropicalis (12.4%), and Candida parapsilosis (8.3%). Gastrointestinal cancer was the most diagnosed pathology type (37.6%). Serum C5a demonstrated a noteworthy correlation with 90-day mortality, and employing a cutoff value of 36.7 ng/ml revealed significantly higher 90-day mortality in low-C5a patients (41.2%) compared to high-C5a patients (6.3%) (p < 0.001). We also identified no source control, no surgery, metastasis, or chronic renal failure independently correlated with the 90-day mortality. Based on this, a prognostic model combining C5a and clinical parameters was constructed, which performed better than models built solely on C5a or clinical parameters. Furthermore, we weighted scores to each parameter in the model and presented diagnostic sensitivity and specificity corresponding to different score points calculated by the model.

CONCLUSION

We constructed a prognostic scoring model including serum C5a and clinical parameters, which would contribute to precise prognosis assessment and benefit the outcome among cancer patients.

Comparative study of posaconazole and voriconazole for primary antifungal prophylaxis in patients with pediatric acute leukemia

Posaconazole and voriconazole are commonly used for preventing invasive fungal disease (IFD), but few studies compared posaconazole with voriconazole for primary antifungal prophylaxis (PAP) in pediatric acute leukemia. To compare posaconazole with voriconazole for PAP in pediatric acute leukemia. This retrospective observational study enrolled pediatric patients with non-M3 acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL) between December 2017 and November 2019 in the Second Affiliated Hospital of Anhui Medical University. The patients received voriconazole or posaconazole for PAP. The primary outcome was the breakthrough of IFD. The secondary outcome was the overall survival (OS) and IFD-free survival of patients. A total of the 275 patients were enrolled, of which 120 patients taking voriconazole (43.6%) and 155 patients taking posaconazole (56.4%). The breakthrough of IFD occurred in 19 (15.8%) patients taking voriconazole and in 12 (7.7%) patients taking posaconazole (P = 0.035). There was no significant differences in IFD-free survival (P = 0.336) or OS (P = 0.069) between the patients taking voriconazole and posaconazole. In the subgroup of AML patients, the OS of patients taking posaconazole was better than those receiving voriconazole (P = 0.017). Posaconazole and voriconazole were comparable for PAP in patients with pediatric acute leukemia regarding the OS and IFD-free survival, but posaconazole might achieve a lower IFD breakthrough rate.

Invasive fungal infections in children with leukemia in a tertiary hospital in Oman: An eight-year review

Background and Purpose

Invasive fungal disease (IFD) is a common and serious consequence of leukemia in children and the incidence of these infections has increased due to chemotherapy. This study aimed to present the epidemiology of IFD in a cohort of children with leukemia from a tertiary reference institution in Oman.

Materials and Methods

A retrospective study of IFDs in pediatric patients below 13 years of age with newly diagnosed or relapsed leukemia was conducted at the Royal Hospital in Muscat, Oman. From 2010 to 2017, IFD episodes in children with leukemia were evaluated retrospectively, considering age, gender, type of leukemia, chemotherapy regimen, IFD detection phase, neutropenia, prevention, diagnostic method, and treatment.

Results

Between 2010 and 2017, 198 children with leukemia were admitted and treated at Royal Hospital. Invasive fungal infection (IFI) was diagnosed in 32 patients out of 198 (16.1%), and IFI was defined as probable and proven in 53% (n=17) and 47% (n=15) of the cases, respectively. At 1.1:1, the male-to-female ratio was roughly equal. According to chest computed tomography scans, 65.6% of patients had radiological features of fungal infections. Positive fungal cultures were found in the bronchoalveolar lavage of three patients, 37.5% of whom had positive blood cultures, and 3% had positive urine cultures as a neonatal invasive candidiasis. In three patients, invasive aspergillosis caused pulmonary IFD, accounting for 9.3% of all infection sites. Candidaemia was found in 28% of IFD patients, and the most common organism was Candida tropicalis (15.6%), followed by Candida parapsilosis (6.25%). Furthermore, the major risk factor was febrile neutropenia.

Conclusion

In children with leukemia, invasive fungal infection is common and serious. Despite aggressive treatment, mortality among these high-risk patients remains high.

Epidemiology and Factors Associated with Treatment Success of Invasive Fungal Infections Among Newly Hematologic Malignancy Patients Receiving Chemotherapy or Hematopoietic Stem Cell Transplant in Thailand

Purpose

Invasive fungal infection (IFI) causes disability/death in patients with hematologic malignancy (HM) receiving chemotherapy or hematopoietic stem cell transplant (HSCT). There is limited epidemiological data, treatment outcomes, and factors associated with IFI treatment success in Thailand. This study aimed to identify factors associated with IFI treatment success among new HM patients receiving chemotherapy or HSCT, determine IFI incidence among HM patients receiving chemotherapy or HSCT, and the IFI incidence of a breakthrough in patients receiving primary antifungal prophylaxis, and identify antifungal drugs susceptibility.

Patients and Methods

This study reviewed the charts of patients aged ≥ 15 years with newly HM who received chemotherapy or HSCT between January 2016 and June 2021 at King Chulalongkorn Memorial Hospital, Bangkok, Thailand. The 2020 EORTC/MSG criteria were used to diagnose IFI. IFI treatment success factors were evaluated using logistic regression.

Results

Ninety-two patients with 107 episodes of IFI met the inclusion criteria. IFI incidence on proven and probable cases among newly HM patients receiving chemotherapy or HSCT was 7%. Most infections (38.3%) occurred during the induction-phase chemotherapy. Aspergillosis (35.5%) was the commonest IFI, followed by candidiasis (11.2%), Pneumocystis jirovecii pneumonia (8.4%), mucormycosis (3.7%), and others, respectively. The 12-week IFI treatment success rate was 67.3%. It was associated with age < 60 years, absence of coinfection, and the receipt of appropriate empirical therapy on the first day of IFI diagnosis. The incidence of breakthrough IFI from proven and probable cases in patients receiving primary antifungal prophylaxis was 6.1%. Most fungal pathogen isolates were still highly susceptible to antifungal drugs.

Conclusion

The IFI treatment success in patients with HM or HSCT in our study was high. Close monitoring of coinfected patients aged ≥ 60 is recommended. Appropriate antifungal drugs are essential for clinical outcomes.

Mold-Active Antifungal Prophylaxis in Pediatric Patients with Cancer or Undergoing Hematopoietic Cell Transplantation

Invasive fungal diseases (IFDs), in particular invasive mold infections, still pose considerable problems in the care of children and adolescents treated for cancer or undergoing hematopoietic cell transplantation. As these infections are difficult to diagnose, and the outcomes for IFDs are still unsatisfactory, antifungal prophylaxis has become an important strategy in the clinical setting. Antifungal prophylaxis is indicated in patients at high risk for IFD, which is commonly defined as a natural incidence of at least 10%. As there is a growing interest in pediatric-specific clinical trials and pediatric-specific guidelines, this review focuses on the available data of mold-active antifungal prophylaxis in children and adolescents. The data demonstrate that a major effort is needed to characterize the pediatric patient population in which the net effect of prophylactic antifungals will be beneficial as well as to find the optimal prophylactic antifungal compound and dosage.

Role of Antifungal Prophylaxis in Invasive Fungal Infection in Children with Acute Lymphoblastic Leukemia—A Retrospective Cross-Sectional Study

Introduction Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. Its outcome in India is not as good as that in the western world. One of the important reasons for lesser survival rates is opportunistic infections, including invasive fungal infections (IFIs). Antifungal prophylaxis (AFP) in ALL children is routinely not followed. However, owing to its incidence in high-risk ALL, this study is focused on the use of AFP in those children.

Objectives This retrospective study investigated the role of AFP in newly diagnosed children with high-risk ALL on intensive blocks of therapy on regimens B and C of the United Kingdom Acute Lymphoblastic Leukemia 2003 protocol.

Materials and Methods The study was conducted in a tertiary care center from 1st December 2013 to 31st December 2019 and included children with ALL from 1 to 18 years of age. Routine AFP with voriconazole was commenced for high-risk ALL children from 1st July 2017 onward in our center. We analyzed data of all IFIs in children before and after AFP with National Cancer Institute high-risk status who had been started on regimen B induction and regimen B or C consolidation and intensification phases.

Results A total of 55 children with high-risk ALL were included in the study. The median age was 4 years, with the majority being between the age of 1 and 10 years (38 out of 55; 65%) and predominantly male (36 out of 55; 69%). Total incidence of IFI in our cohort was 51% (28 out of 55). A significant number of children (16 out of 22 [70%]) who were not on prophylaxis developed IFI versus children (12 out of 33 [28%]) on prophylaxis (p = 0.008). The most common organisms isolated were Candida parapsilosis and Candida tropicalis. Children not receiving AFP were found to be 4.7 times (95% confidence interval: 1.44–15.13) more likely to get IFI than the ones receiving AFP. The presence of concurrent bacterial infection increases the risk of IFI (p = 0.04).

Conclusion The incidence of IFI was high in high-risk ALL children who were not on AFP. The introduction of routine AFP reduced the incidence of IFI.