Successful Treatment of Disseminated Fusariosis in a 15-Month-Old Boy With Refractory Acute Lymphoblastic Leukemia Using High-Dose Voriconazole.

BACKGROUND: Infections due to rare molds, such as Fusarium spp., cause severe and difficult-to-control diseases with increasing frequency. Data on fusariosis in children and on the use of voriconazole (VCZ), considered a drug of choice, are scarce in infants and children <2 years of age. CASE PRESENTATION: We present the first, to our knowledge, pediatric case of disseminated mycosis due to Fusarium musae in a 15-month-old boy with relapsed/refractory acute lymphoblastic leukemia, diagnostics and outcome. Herein, at this severely immunocompromised patient, after prompt diagnosis, disseminated fusariosis was successfully treated with high-dose VCZ at a final dose of 15 mg/kg of body weight twice a day. This occurred by achieving adequate drug exposures as determined by drug susceptibility testing and followed by therapeutic drug monitoring without observed toxicity. CONCLUSIONS: Appropriate diagnostic approach and timely administration of optimal antifungal therapy with VCZ were important for the successful treatment of disseminated fusariosis. Therapeutic drug monitoring, especially in <2-year-old children, is necessary to achieve sufficient drug exposure for optimal therapeutic response without toxicity.

Case report: Concurrent low-volume subdural hematoma and ipsilateral ischemic stroke presenting as capsular warning syndrome: a complex case with anticoagulation dilemma and dual pathology.

Background: The simultaneous emergence of low-volume subdural hematoma and ipsilateral ischemic stroke in an atrial fibrillation patient who is under anticoagulation therapy is a rare and intricate clinical case. This report accentuates the diagnostic and treatment complexities associated with these consecutive neurological conditions. Case presentation: An 83 years-old male patient initially presented with acute dyspnea, raising the suspicion of pulmonary embolism. After exclusion of pulmonary embolism through CT angiography, the patient experienced a sudden onset of left-sided hemiparesis without prior history of head trauma but with chronic intake of apixaban due to atrial fibrillation. Subsequent cranial CT tomography revealed a small right parietal subdural hematoma. After reversal of the anticoagulation therapy, surgical evacuation of the subdural hematoma was successfully performed. However, in the postoperative period, the patient developed new neurological symptoms that could not be explained by the reduced size of the subdural hematoma on a follow-up CT scan. Cranial MRI revealed the coexistence of acute ischemic stroke in the right corona radiata. The recent surgical procedure precluded guideline-recommended stroke treatment. Discussion: This case underscores the complexities of diagnosing and treating concomitant small volume subdural hematoma and ischemic stroke, especially if the latter occurs in the corona radiata resulting in fluctuating symptoms known as "capsular warning syndrome." Reversal and secondary discontinuation of anticoagulant therapy for surgical intervention highlight the inherent risk of thrombotic events in anticoagulated patients. The development of tailored treatment strategies requires a multidisciplinary approach, and further research and guidelines are required in similar complex scenarios. Conclusion: The presence of both a small subdural hematoma and an ipsilateral ischemic stroke presenting as capsular warning syndrome in an anticoagulated patient highlights the intricacy of their care. This case calls for a comprehensive and collaborative strategy to address complicated clinical scenarios.

Structural and functional features of a broad-spectrum prophage-encoded enzybiotic from Enterococcus faecium.

Multidrug-resistant (MDR) bacteria have become a growing threat to public health. The gram-positive Enterococcus faecium is classified by WHO as a high-priority pathogen among the global priority list of antibiotic-resistant bacteria. Peptidoglycan-degrading enzymes (PDEs), also known as enzybiotics, are useful bactericidal agents in the fight against resistant bacteria. In this work, a genome-based screening approach of the genome of E. faecium allowed the identification of a putative PDE gene with predictive amidase activity (EfAmi1; EC 3.5.1.28) in a prophage-integrated sequence. EfAmi1 is composed by two domains: a N-terminal Zn2+-dependent N-acetylmuramoyl-L-alanine amidase-2 (NALAA-2) domain and a C-terminal domain with unknown structure and function. The full-length gene of EfAmi1 was cloned and expressed as a 6xHis-tagged protein in E. coli. EfAmi1 was produced as a soluble protein, purified, and its lytic and antimicrobial activities were investigated using turbidity reduction and Kirby-Bauer disk-diffusion assays against clinically isolated bacterial pathogens. The crystal structure of the N-terminal amidase-2 domain was determined using X-ray crystallography at 1.97 Å resolution. It adopts a globular fold with several α-helices surrounding a central five-stranded ß-sheet. Sequence comparison revealed a cluster of conserved amino acids that defines a putative binding site for a buried zinc ion. The results of the present study suggest that EfAmi1 displays high lytic and antimicrobial activity and may represent a promising new antimicrobial in the post-antibiotic era.

Metaviromics analysis of marine biofilm reveals a glycoside hydrolase endolysin with high specificity towards Acinetobacter baumannii.

Multidrug-resistant (MDR) bacteria are a growing threat to the public health. Among them, the Gram-negative Acinetobacter baumannii is considered today as the most dangerous MDR pathogen. Phage-derived endolysins are peptidoglycan (PG) hydrolytic enzymes that can function as effective tools in the fight against MDR bacteria. In the present work, the viral diversity of a marine environmental sample (biofilm), formed near an industrial zone, was mined for the identification of a putative endolysin (AbLys2) that belongs to the glycoside hydrolase family 24 (GH24, EC 3.2.1.17). The coding sequence of AbLys2 was cloned and expressed in E. coli. The lytic activity and specificity of the recombinant enzyme were evaluated against suspensions of a range of Gram-positive and Gram-negative human pathogens using turbidity assays. AbLys2 displayed enhanced selectivity towards A. baumannii cells, compared to other bacteria. Kinetics analysis was carried out to characterize the dependence of its lytic activity on pH and showed that the enzyme exhibits its maximal activity at pH 5.5. Thermostability analysis showed that AbLys2 displays melting temperature Tm 47.1 °C. Florescence microscopy and cell viability assays established that AbLys2 is active towards live cultures of A. baumannii cells with an inhibitory concentration IC50 3.41 ± 0.09 µM. Molecular modeling allowed the prediction of important amino acid residues involved in catalysis. The results of the present study suggest that AbLys2 provides efficient lytic and antimicrobial activity towards A. baumannii cells and therefore is a promising new antimicrobial against this pathogen.

Characterization of a glycoside hydrolase endolysin from Acinetobacter baumannii phage AbTZA1 with high antibacterial potency and novel structural features.

The classification of Acinetobacter baumannii by WHO as 'priority 1' antibiotic-resistant pathogen underlines the urgent need for novel antimicrobial agents towards this pathogen. In this work, screening of the A. baumannii phage AbTZA1 genome allowed the identification of a putative endolysin (AbLys1, EC3.2.1.17) that belongs to the glycoside hydrolase family 24 (GH24). The sequence of AbLys1 was cloned, expressed in E. coli and purified. The lytic activity and specificity of AbLys1 were evaluated against a range of Gram-positive and Gram-negative human pathogens. AbLys1 was found to display a high selectivity towards A. baumannii. Kinetic analysis was carried out to characterize the dependence of its lytic activity on pH. The enzyme shows its maximal activity at pH values 7-8. The structure of AbLys1 was determined by X-ray crystallography to 1.82 Å resolution. The overall structure revealed two helical domains: a small, antenna-like, N-terminal domain and a larger C-terminal domain with six α-helices and a ß-hairpin. Both the antenna-like and ß-hairpin regions contain short sequences (AMseq1 and AMseq2) with predicted antimicrobial activity. Engineering studies revealed a key role of AMseq1 and AMseq2 on the enzyme's lytic activity towards A. baumannii cells but not towards purified peptidoglycan. This suggests that both sequences affect the destabilization of the outer membrane, thus providing access of the catalytic domain to the peptidoglycan. In addition, the deletion of AMseq1 enhanced the enzyme stability, whereas the deletion of AMseq2 diminished it. The results suggest that AbLys1 is a promising new enzybiotic with efficient lytic and antimicrobial activity.

Rare Invasive Yeast Infections in Greek Neonates and Children, a Retrospective 12-Year Study.

Although Candida species remain the leading cause of invasive fungal infections (IFI), the list of other isolated fungal pathogens is increasing. The aim of the study was to report cases of IFI caused by rare yeasts in the largest tertiary Greek pediatric hospital. A retrospective study was performed from 6/2008-6/2020 regarding IFI caused by rare species. Identification of isolates was attained by conventional, molecular, and MALDI TOF MS methods, and susceptibility testing was performed according to the Clinical and Laboratory Standards (CLSI) methodology. During a 12-year period, 14 different rare fungal species in 33 neonates and children with IFI hospitalized in intensive care and oncology units were isolated from blood, central catheters, peritoneal, pleural, or pericardial fluid specimens. It is the first time for IFI caused by Wickerhamomyces anomalus (Candida pelliculosa), Pichia fermentans (Candida lambica), Yarrowia (Candida) lipolytica, Pichia (Hansenula) kluyveri, Rhodotorula mucilaginosa, Wickerhamiella (Candida) pararugosa and Cyberlindnera (Candida) fabianii in Greek neonates and children to be reported. For most of these rare fungal species isolated in the present study, no official antifungal breakpoints have been defined, and there are no guidelines for their treatment. Clinical laboratories should be aware of uncommon and emerging yeast pathogens and be able to detect them with molecular and proteomic methods.

Isolation of Candida auris from cystic fibrosis patient, Greece, April 2019.

We report the first isolation of Candida auris in Greece from a sputum culture of a cystic fibrosis patient in their 20s under posaconazole treatment. The pathogen was identified as C. duobushaemulonii by VITEK2YST, but as C. auris by MALDI-TOF MS. This case underscores the need for species-level identification of all non-albicans Candida (NAC) isolates from cystic fibrosis patients and patients with predisposing factors to fungal infection.

Changing Epidemiology of Invasive Candidiasis in Children during a 10-Year Period.

Candida species are a common cause of invasive infection in neonates and children. The aim of our study was to evaluate the epidemiology and microbiology of invasive candidiasis (IC) in the largest tertiary Greek pediatric hospital during a 10-year period. A retrospective cohort study was performed from January 2008 to December 2017. Identification of species and antifungal susceptibility testing was performed according to the Clinical and Laboratory Standards Institute (CLSI) methodology. During the study period, 178 cases of IC were recorded. The tissue distribution included blood (87.1%), cerebrospinal (7.9%), peritoneal (3.9%) and pleural fluids (1.1%). Candida albicans and Candida parapsilosis (sensu lato) were the most frequently isolated species (47.8% and 28.7% respectively). From period 2008⁻2012 to period 2013⁻2017, a significant decrease in IC rates was detected (0.21 cases/1000 hospitalization days VS 0.11 cases/1000 hospitalization days, P = 0.040), while median minimum inhibitory concentrations (MICs) of amphotericin B were significantly increased for both C. albicans and C. parapsilosis (sl) (P = 0.037 and P = 0.004 respectively). The decrease in IC rates may reflect the increased awareness as well as the effective infection control initiatives and antifungal interventions. However, the significant increase in the MICs for amphotericin B and echinocandins such as caspofungin, raises concerns about their common use as first-line treatment. Epidemiologic monitoring is, therefore, critically important in order to evaluate and optimize therapeutic protocols for IC in pediatric populations.

Drug reaction with eosinophilia and systemic symptoms after daclizumab therapy.

OBJECTIVE: To report on 2 women with multiple sclerosis (MS) who developed severe neurologic deterioration and a drug reaction with eosinophilia and systemic symptoms (DRESS) after treatment with 2 and 4 subcutaneous injections of daclizumab, respectively. METHODS: This report includes clinical, MRI, and histopathologic data. RESULTS: Daclizumab is a humanized monoclonal antibody that binds the interleukin-2 receptor. It was approved for the treatment of relapsing MS. DRESS is an immunologic reaction to various medications that is characterized by eosinophilia as well as cutaneous and visceral manifestations. Following daclizumab treatment, both patients showed fulminant neurologic deterioration along with blood eosinophilia and skin changes, and both fulfilled the clinical criteria for the diagnosis of DRESS. They presented with multiple gadolinium-enhancing supra- and infratentorial lesions, with lesions in the basal ganglia, mesencephalon, and cerebellum. Brain biopsies revealed a pronounced inflammatory infiltrate including numerous eosinophils infiltrating demyelinating lesions, a feature that is atypical for MS but compatible with DRESS. In addition, numerous plasma cells and changes reminiscent of vasculitis were evident. CONCLUSIONS: Neurologic deterioration and DRESS occurred as severe adverse drug effects of daclizumab treatment. Early diagnosis and treatment of DRESS are essential because it is associated with complications such as new autoimmune diseases and liver failure, and may even be lethal. Because of its potential serious side effects, daclizumab was recently suspended for use in the European Union.

Scedosporium apiospermum complex in cystic fibrosis; should we treat?

Species of the Scedosporium apiospermum complex are the second most frequent filamentous fungi after Aspergillus fumigatus that can be found in cystic fibrosis (CF). Mixed colonisation by S. apiospermum complex and A. fumigatus is also quite common. In this study we summarise all CF patients who were colonised by S. apiospermum complex during their childhood and we present two CF patients who were treated as fungal bronchitis due to S. apiospermum complex. The medical records of 400 CF patients were reviewed in order to identify those with positive respiratory cultures for S. apiospermum complex. Scedosporium apiospermum complex was isolated in 10 CF patients and six of them had more than two positive sputum cultures during the study period. By the time of first isolation, the median age was 14.5 years, the median BMI was 19.41 kg/m2 , the median predicted FEV1 % was 78.65% and six patients had a history of A. fumigatus isolation. Two patients presented symptoms of infection while they were colonised by S. apiospermum complex. A rapid remission of their symptoms was observed only when antifungal therapy was administered. Antifungal treatment should be considered in CF patients who present symptoms of infection not responding to antibacterial therapy and S. apiospermum complex is persistently growing in sputum cultures.