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Heliyon May 2024is a recently discovered and not widely documented ascomycetous yeast phylogenetically related to the outbreak-causing and multidrug-resistant . A middle-aged Japanese...
is a recently discovered and not widely documented ascomycetous yeast phylogenetically related to the outbreak-causing and multidrug-resistant . A middle-aged Japanese man with no discernible immunodeficiency was admitted to hospital with ileal diverticulitis. Following laparoscopic right hemicolectomy against abscess formation on postoperative day (POD) 7, continuous fungemia occurred due to identified using a conventional method by confirming the biochemical phenotype. Micafungin was initiated; however, the fungus was persistently isolated from blood cultures. Eventually, the antifungal agent was changed to a combination of liposomal amphotericin B (L-AMB) and caspofungin (CPFG), which cleared the infection, and no pathogens were detected in the blood cultures on POD 31. Contrast-enhanced computed tomography showed septic emboli in the lungs and spleen; however, no evidence of vasculitis was observed. Moreover, sequential echocardiography did not reveal any signs of infectious endocarditis. Finally, CPFG and L-AMB were administered to the patient for 7 and 9 weeks, respectively, during which the patient's symptoms did not relapse. The strain was later genetically identified as . This case report illustrates a clinical presentation of and provides the diagnostic approach and treatment methods for this pathogen.
PubMed: 38803887
DOI: 10.1016/j.heliyon.2024.e31464 -
Indian Journal of Medical Microbiology May 2024Candida auris is emerging as an important cause of candidemia and deep seated candidal infection. We compared the susceptibility results of bloodstream Candida auris...
INTRODUCTION
Candida auris is emerging as an important cause of candidemia and deep seated candidal infection. We compared the susceptibility results of bloodstream Candida auris isolates by Vitek 2 with Sensititre YeastOne (SYO) method.
METHODS
Forty-seven C. auris blood stream isolates were simultaneously tested for AFST by Vitek 2 and SYO.
RESULTS
All strains were resistant to Fluconazole. 25.5% isolates showed pan-azole resistance. In comparison with SYO, lower MICs for voriconazole were noted with Vitek 2 (VME rate 76.1%). All strains were sensitive to anidulafungin and micafungin by SYO. For micafungin, Vitek 2 demonstrated higher MICs and an ME rate of 23.5%. Susceptibility interpretation of caspofungin by SYO was challenged by development of 'Eagle effect' resulting in sensitivity of 28.2%. We studied the evolution of caspofungin 'Eagle effect' with SYO by serial hourly MIC readings and noted that paradoxical growth commenced at 21 hrs of incubation. Compared to SYO, Vitek 2 showed higher resistance rate to Amphotericin B with ME rate of 25.6%.
CONCLUSION
Laboratories using commercial AFST systems for Candida auris need to be aware of the possibility of ME and VME for amphotericin B and voriconazole respectively with Vitek 2 and 'Eagle effect' for caspofungin with SYO.
PubMed: 38795936
DOI: 10.1016/j.ijmmb.2024.100618 -
BMC Infectious Diseases May 2024Lagenidium deciduum is an oomycete that can cause infections in mammals that present similarly to pythiosis and mucormycosis. Most of the existing case reports have...
BACKGROUND
Lagenidium deciduum is an oomycete that can cause infections in mammals that present similarly to pythiosis and mucormycosis. Most of the existing case reports have occurred in canines and have been fatal. In animals, medical therapy has not been successful, so surgical excision is the mainstay of treatment. Lagenidium sp. infections in humans are rare. There is only one case of a human Lagenidium sp. infection in the literature, and it presented as an ocular infection. The human ocular infection was resistant to medical therapy and required a penetrating keratoplasty for cure. Additional reports of effective therapy are needed to guide management of this emerging pathogen. We present the first case of a cutaneous Lagenidium deciduum infection in a human patient, which is also the first documented case of a Lagenidium deciduum infection in an immunocompromised host of any species.
CASE PRESENTATION
An 18-year-old female with relapsed acute myeloid leukemia, awaiting a haploidentical stem cell transplant, presented with erythematous cutaneous lesions on her left hip and bilateral buttocks that enlarged and blackened over several days. About 1 week later, boil-like lesions appeared on her bilateral buttocks. The skin lesions were initially presumed to be bacterial in origin, so the patient was treated with clindamycin and cefepime with little improvement. Upon further investigation, fungal cultures and skin biopsies revealed aseptate hyphae, so the patient was switched to isavuconazole and amphotericin B due to concern for mucormycosis. Phenotypic characterization and DNA sequencing were performed by the Fungus Testing Laboratory, University of Texas Health Science Center at San Antonio, which identified the causal fungal organism as Lagenidium deciduum. All of her cutaneous lesions were surgically excised, and the patient was treated with micafungin, terbinafine, doxycycline, and azithromycin. Micafungin and terbinafine were continued until she achieved engraftment post-transplant.
CONCLUSIONS
We report the first successful treatment of a human Lagenidium infection in an immunocompromised host through a combination of aggressive surgical excision and prolonged antifungal therapy during the prolonged neutropenia associated with allogeneic stem cell transplant. Prompt diagnosis and management may prevent disseminated oomycosis.
Topics: Humans; Female; Leukemia, Myeloid, Acute; Antifungal Agents; Adolescent; Lagenidium; Dermatomycoses; Immunocompromised Host
PubMed: 38778275
DOI: 10.1186/s12879-024-09281-5 -
Einstein (Sao Paulo, Brazil) 2024This study aimed to verify oral candidiasis, identify the causative species, and investigate the antifungal susceptibility of yeasts isolated from liver transplant...
OBJECTIVE
This study aimed to verify oral candidiasis, identify the causative species, and investigate the antifungal susceptibility of yeasts isolated from liver transplant patients.
METHODS
A descriptive analysis of 97 patients who underwent liver transplantation was conducted at a hospital. Two clinical examinations (Collections A and B) of the oral cavity were performed. Oral material was collected from all patients, inoculated in Sabouraud Dextrose Agar, and incubated at 35℃ for 48 hours. Samples were identified by molecular sequencing of the internal trascribed space region of rDNA.
RESULTS
An antifungal susceptibility test with fluconazole, amphotericin B, and micafungin was performed using the Clinical and Laboratory Standards Institute yeast broth microdilution method. Among the patients, 15 presented with oral candidiasis: eight in Collection A and seven in Collection B. The primary type of candidiasis was atrophic, followed by pseudomembranous candidiasis. The most prevalent species was Candida albicans (nine), followed by Candida glabrata (three), Candida tropicalis (two), and Candida dubliniensis (one). Regarding susceptibility to fluconazole, of the 15 samples, 11 were susceptible, three were susceptible in a dose-dependent manner, and one was resistant.
CONCLUSION
The most commonly identified type of candidiasis was atrophic, with C. albicans and C. glabrata being the most prevalent causative species. One fluconazole-resistant isolate each of C. tropicalis and C. albicans were identified.
Topics: Humans; Antifungal Agents; Microbial Sensitivity Tests; Liver Transplantation; Male; Candidiasis, Oral; Female; Middle Aged; Candida; Fluconazole; Adult; Amphotericin B; Aged; Drug Resistance, Fungal; Micafungin; Young Adult
PubMed: 38775603
DOI: 10.31744/einstein_journal/2024AO0138 -
Scientific Reports May 2024Candida is the most prevalent fungal bloodstream infection (BSI) with a high mortality rate among hospitalized patients. Another concern facing physicians is rising...
Candida is the most prevalent fungal bloodstream infection (BSI) with a high mortality rate among hospitalized patients. Another concern facing physicians is rising global incidence of drug-resistant Candida. This study aimed to characterize the prevalence, antifungal susceptibility, biofilm formation, and virulence genes (HWP1, ALS1, SAP2) of different Candida spp. isolated from patients with candidemia. 52 isolates of Candida spp. were identified from blood cultures by chromogenic Candida agar and confirmed by the VITEK 2 system. Isolates were tested for antifungal susceptibility by disk diffusion and VITEK 2 system. Biofilm formation and investigated genes were detected by the Congo red method and conventional PCR, respectively. Candida spp. caused 2.3% of detected BSIs, of which 32.7% were caused by Candida albicans (C. albicans) and 67.3% by non-albicans Candida (NAC), with the predominance of C. tropicalis (25%), followed by C. parapsilosis (17.3%), and C. krusei (13.5%). The susceptibility rates to fluconazole, voriconazole, caspofungin, micafungin, amphotericin B, and flucytosine were 64.7%, 76.5%, 100.0%, 100%, 100.0%, and 100.0% in C. albicans, while 53.6%, 71.4%, 91.4%, 91.4%, 94.3%, and 94.3% in NAC, respectively. Biofilm production, HWP1, ALS1, and SAP2 were detected in 70.6%, 82.4%, 76.5%, and 52.9% of C. albicans and 74.3%, 85.7%, 80.0%, and 48.6% of NAC, respectively. There is remarkable shift to NAC BSIs and high azole resistance. Antifungal stewardship and analysis of risk factors associated with this shift are needed.
Topics: Humans; Candidemia; Antifungal Agents; Biofilms; Microbial Sensitivity Tests; Candida; Drug Resistance, Fungal; Virulence Factors; Virulence; Female; Male; Middle Aged; Adult
PubMed: 38773138
DOI: 10.1038/s41598-024-61813-w -
Journal de Mycologie Medicale Jun 2024Fungal infections in neonatal intensive care units (NICU) are mainly related to Candida species, with high mortality rates. They are predominantly of endogenous origin,...
Virulence factors, antifungal susceptibility and molecular profile in Candida species isolated from the hands of health professionals before and after cleaning with 70% ethyl alcohol-based gel.
Fungal infections in neonatal intensive care units (NICU) are mainly related to Candida species, with high mortality rates. They are predominantly of endogenous origin, however, cross-infection transmitted by healthcare professionals' hands has occurred. The aim of this study was to identify Candida species isolated from the hands of healthcare professionals in a NICU before and after hygiene with 70% ethanol-based gel and evaluate virulence factors DNase, phospholipase, proteinase, hemolysin, biofilm biomass production, and metabolic activity. In vitro antifungal susceptibility testing and similarity by random amplified polymorphic DNA (RAPD) were also performed. C. parapsilosis complex was the most frequent species (57.1%); all isolates presented at least one virulence factor; three isolates (Candida parapsilosis complex) were resistant to amphotericin B, two (Candida famata [currently Debaryomyces hansenii] and Candida guilliermondii [currently Meyerozyma guilliermondii]) was resistant to micafungin, and six (Candida parapsilosis complex, Candida guilliermondii [=Meyerozyma guilliermondii], Candida viswanathi, Candida catenulata [currently Diutina catenulata] and Candida lusitaniae [currently Clavispora lusitaniae]) were resistant to fluconazole. Molecular analysis by RAPD revealed two clusters of identical strains that were in the hands of distinct professionals. Candida spp. were isolated even after hygiene with 70% ethanol-based gel, highlighting the importance of stricter basic measures for hospital infection control to prevent nosocomial transmission.
Topics: Humans; Hand; Antifungal Agents; Microbial Sensitivity Tests; Virulence Factors; Candida; Ethanol; Cross Infection; Candidiasis; Health Personnel; Random Amplified Polymorphic DNA Technique; Biofilms; Intensive Care Units, Neonatal; Drug Resistance, Fungal; Gels; Hand Disinfection
PubMed: 38763122
DOI: 10.1016/j.mycmed.2024.101482 -
BioRxiv : the Preprint Server For... May 2024is an opportunistic pathogen that can resist common antifungals and rapidly acquire multidrug resistance. A large amount of genetic variation exists between isolates,...
UNLABELLED
is an opportunistic pathogen that can resist common antifungals and rapidly acquire multidrug resistance. A large amount of genetic variation exists between isolates, which complicates generalizations. Portable Tn-seq methods can efficiently provide genome-wide information on strain differences and genetic mechanisms. Using the transposon, the CBS138 reference strain and a commonly studied derivative termed 2001 were subjected to Tn-seq in control conditions and after exposure to varying doses of the clinical antifungal micafungin. The approach revealed large differences between these strains, including a 131 kb tandem duplication and a variety of fitness differences. Additionally, both strains exhibited up to 1000-fold increased transposon accessibility in subtelomeric regions relative to the BG2 strain, indicative of open subtelomeric chromatin in these isolates and large epigenetic variation within the species. Unexpectedly, the Pdr1 transcription factor conferred resistance to micafungin through targets other than . Other micafungin resistance pathways were also revealed including mannosyltransferase activity and biosynthesis of the lipid precursor sphingosine, the drugging of which by SDZ 90-215 or myriocin enhanced the potency of micafungin . These findings provide insights into complexity of the species as well as strategies for improving antifungal efficacy.
SUMMARY
Candida glabrata is an emerging pathogen with large genetic diversity and genome plasticity. The type strain CBS138 and a laboratory derivative were mutagenized with the transposon and profiled using Tn-seq. Numerous genes that regulate innate and acquired resistance to an important clinical antifungal were uncovered, including a pleiotropic drug resistance gene (PDR1) and a duplication of part of one chromosome. Compounds that target PDR1 and other genes may augment the potency of existing antifungals.
PubMed: 38746084
DOI: 10.1101/2024.05.02.592251 -
Mycopathologia May 2024Candida parapsilosis complex has recently received special attention due to naturally occurring FKS1 polymorphism associated with high minimal inhibitory concentrations...
Candida parapsilosis complex has recently received special attention due to naturally occurring FKS1 polymorphism associated with high minimal inhibitory concentrations for echinocandin and the increase of clonal outbreaks of strains resistant to commonly used antifungals such as fluconazole. Despite the previous fact, little is known about the genetic mechanism associated with echinocandin resistance. Therefore, the present study was designed to investigate the mechanism of acquired echinocandin resistance in C. parapsilosis complex strains. A total of 15 clinical C. parapsilosis complex isolates were sub-cultured for 30 days at a low concentration of micafungin at ½ the lowest MIC value of the tested isolates (0.12 µg/ml). After culturing, all the isolates were checked phenotypically for antifungal resistance and genotypically for echinocandin resistance by checking FKS1 gene hot spot one (HS1) and HS2 mutations. In vitro induction of echinocandin resistance confirmed the rapid development of resistance at low concentration micafungin, with no difference among C. parapsilosis, C. metapsilosis, and C. orthopsilosis in the resistance development. For the first time we identified different FKS1 HS1 and or HS2 mutations responsible for echinocandin resistance such as R658S and L1376F in C. parapsilosis, S656X, R658X, R658T, W1370X, X1371I, V1371X, and R1373X (corresponding to their location in C. parapsilosis) in C. metapsilosis, and L648F and R1366H in C. orthopsilosis. Our results are of significant concern, since the rapid development of resistance may occur clinically after short-term exposure to antifungals as recently described in other fungal species with the potential of untreatable infections.
Topics: Humans; Antifungal Agents; Candida parapsilosis; Candidiasis; Drug Resistance, Fungal; Echinocandins; Fungal Proteins; Glucosyltransferases; Micafungin; Microbial Sensitivity Tests; Mutation; Mutation, Missense
PubMed: 38704798
DOI: 10.1007/s11046-024-00847-0 -
Infection and Drug Resistance 2024Lymphoma is complicated by intricate infections, notably pneumonia (PJP), marked by rapid progression, respiratory failure, and high mortality. Rapid diagnosis of PJP...
BACKGROUND
Lymphoma is complicated by intricate infections, notably pneumonia (PJP), marked by rapid progression, respiratory failure, and high mortality. Rapid diagnosis of PJP and effective administration of the first-line treatment trimethoprim-sulfamethoxazole (TMP-SMX) are important. For patients intolerant to TMP-SMX, selecting appropriate alternatives is challenging, necessitating careful decisions to optimize diagnosis and treatment. We present a lymphoma case complicated by PJP, illustrating medication adjustment until a positive response was observed.
CASE DESCRIPTION
A 41-year-old male patient with lymphoma presented with a week-long history of fever, fatigue, cough, sputum, chest tightness, and exertional dyspnea, unresponsive to treatment. Routine laboratory examinations revealed no pathogenic bacteria. PJ and (MTB) were detected in bronchoalveolar lavage fluid (BALF) using metagenomic next-generation sequencing (mNGS). On Day 1 of admission, meropenem, TMP-SMX, and rifampicin+isoniazid+levofloxacin were administered. However, the patient developed drug-induced hepatotoxicity and gastrointestinal adverse reactions after six days of treatment. After a multidisciplinary team discussion, anti-tuberculosis therapy was stopped because of insufficient evidence of tuberculosis infection. A reduced dose of TMP-SMX with micafungin was used for PJP; however, symptoms persisted and repeated computed tomography showed extensive deterioration of bilateral pulmonary plaques. The PJP regimen was modified to include a combination of TMP-SMX and caspofungin. Due to the high fever and elevated infection indices, the patient was treated with teicoplanin to enhance the anti-infection effects. By Day 13, the patient's temperature had normalized, and infection control was achieved by Day 30. CT revealed that the infection in both lung lobes fully resolved. Subsequently, lymphoma treatment commenced.
CONCLUSION
BALF-NGS facilitates early and rapid diagnosis of PJP. mNGS reads of MTB bacillus <5 may indicate a bacterial carrier state, warranting other detection techniques to support it. There is insufficient evidence for using TMP-SMX with micafungin to treat PJP; however, TMP-SMX combined with caspofungin is suitable.
PubMed: 38681899
DOI: 10.2147/IDR.S461607 -
Medical Mycology Case Reports Jun 2024A 46-year-old diabetic woman with unilateral renal fungus ball was successfully treated with antifungal therapy, endoscopic extraction and ureteral stent placement. The...
A 46-year-old diabetic woman with unilateral renal fungus ball was successfully treated with antifungal therapy, endoscopic extraction and ureteral stent placement. The patient was initially treated for a right staghorn calculus, thereafter developed urinary symptoms. Imaging revealed distal left ureter filling defects and a previous stent at the ureteropelvic junction. Urine culture confirmed sensitive to Micafungin. Bilateral ureteroscopy facilitated the extraction of a left renal pelvis fungus ball. This case underscores the challenges in diagnosing fungal UTIs in patients with predisposing factors, and highlights a combined medical and surgical approach for effective treatment of renal fungus balls.
PubMed: 38681664
DOI: 10.1016/j.mmcr.2024.100649