1
|
Jabeen G, Naz SA, Rangel DEN, Jabeen N, Shafique M, Yasmeen K. In-vitro evaluation of virulence markers and antifungal resistance of clinical Candida albicans strains isolated from Karachi, Pakistan. Fungal Biol 2023; 127:1241-1249. [PMID: 37495314 DOI: 10.1016/j.funbio.2023.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 04/09/2023] [Accepted: 04/11/2023] [Indexed: 07/28/2023]
Abstract
Candidiasis is a significant fungal infection with high mortality and morbidity rates worldwide. Candida albicans is the most dominant species responsible for causing different manifestations of candidiasis. Certain virulence traits as well as its resistance to antifungal drugs contribute to the pathogenesis of this yeast. This study was designed to determine the production of some virulence factors, such as biofilm formation and extracellular hydrolytic enzymes (esterase, coagulase, gelatinase, and catalase) by this fungus, as well as its antifungal resistance profile. A total of 304 clinical C. albicans isolates obtained from different clinical specimens were identified by a conventional diagnostic protocol. The antifungal susceptibility of C. albicans strains was determined by disk diffusion technique against commercially available antifungal disks, such as nystatin 50 μg, amphotericin B 100 unit, fluconazole 25 μg, itraconazole 10 μg, ketoconazole 10 μg, and voriconazole 1 μg. The assessment of biofilm formation was determined by the tube staining assay and spectrophotometry. Gelatinase, coagulase, catalase, and esterase enzyme production was also detected using standard techniques. A total of 66.1% (201/304) and 28.9% (88/304) of C. albicans strains were susceptible-dose dependent (SDD) to nystatin and itraconazole, respectively. Among the antifungal drugs, C. albicans strains showed high resistance to ketoconazole 24.7% (75/304); however, no statistically significant relationship between the clinical origin of C. albicans isolates and antifungal drug resistance pattern was detected. For virulence factors, the majority of the C. albicans strains actively produced biofilm and all hydrolytic enzymes. Biofilm formation was demonstrated by 88% (267/304) of the strains with a quantitative mean value 0.1762 (SD ± 0.08293). However, 100% (304/304) of isolates produced catalase enzyme, 69% (211/304) produced coagulase, 66% (197/304) produced gelatinase, and 52% (157/304) produced esterase enzyme. A significant relationship between the source of specimens and biofilm formation by C. albicans was observed; nevertheless, there was no significant relationship between different sources of C. albicans strains and the production of different enzymatic virulence factors. The study found that C. albicans strains have excellent potential to produce virulence markers and resistance to antifungals, which necessitates surveillance of these opportunistic pathogens to minimize the chances of severe invasive infections.
Collapse
Affiliation(s)
- Gul Jabeen
- Lab of Applied Microbiology and Clinical Mycology, Department of Microbiology, Federal Urdu University of Arts, Science and Technology, Gulshan Iqbal, Karachi, 75300, Pakistan; Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Sehar Afshan Naz
- Lab of Applied Microbiology and Clinical Mycology, Department of Microbiology, Federal Urdu University of Arts, Science and Technology, Gulshan Iqbal, Karachi, 75300, Pakistan.
| | - Drauzio E N Rangel
- Universidade Tecnológica Federal do Paraná, Dois Vizinhos, Paraná, 85660-000, Brazil
| | - Nusrat Jabeen
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Maryam Shafique
- Lab of Applied Microbiology and Clinical Mycology, Department of Microbiology, Federal Urdu University of Arts, Science and Technology, Gulshan Iqbal, Karachi, 75300, Pakistan
| | - Kousar Yasmeen
- Department of Chemistry, Federal Urdu University of Arts, Science and Technology, Gulshan, Iqbal, Karachi, 75300, Pakistan
| |
Collapse
|
2
|
Toda M, Williams SR, Berkow EL, Farley MM, Harrison LH, Bonner L, Marceaux KM, Hollick R, Zhang AY, Schaffner W, Lockhart SR, Jackson BR, Vallabhaneni S. Population-Based Active Surveillance for Culture-Confirmed Candidemia - Four Sites, United States, 2012-2016. MORBIDITY AND MORTALITY WEEKLY REPORT. SURVEILLANCE SUMMARIES (WASHINGTON, D.C. : 2002) 2019; 68:1-15. [PMID: 31557145 PMCID: PMC6772189 DOI: 10.15585/mmwr.ss6808a1] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
PROBLEM/CONDITION Candidemia is a bloodstream infection (BSI) caused by yeasts in the genus Candida. Candidemia is one of the most common health care-associated BSIs in the United States, with all-cause in-hospital mortality of up to 30%. PERIOD COVERED 2012-2016. DESCRIPTION OF SYSTEM CDC's Emerging Infections Program (EIP), a collaboration among CDC, state health departments, and academic partners that was established in 1995, was used to conduct active, population-based laboratory surveillance for candidemia in 22 counties in four states (Georgia, Maryland, Oregon, and Tennessee) with a combined population of approximately 8 million persons. Laboratories serving the catchment areas were recruited to report candidemia cases to the local EIP program staff. A case was defined as a blood culture that was positive for a Candida species collected from a surveillance area resident during 2012-2016. Isolates were sent to CDC for species confirmation and antifungal susceptibility testing. Any subsequent blood cultures with Candida within 30 days of the initial positive culture in the same patient were considered part of the same case. Trained surveillance officers collected clinical information from the medical chart for all cases, and isolates were sent to CDC for species confirmation and antifungal susceptibility testing. RESULTS Across all sites and surveillance years (2012-2016), 3,492 cases of candidemia were identified. The crude candidemia incidence averaged across sites and years during 2012-2016 was 8.7 per 100,000 population; important differences in incidence were found by site, age group, sex, and race. The crude annual incidence was the highest in Maryland (14.1 per 100,000 population) and lowest in Oregon (4.0 per 100,000 population). The crude annual incidence of candidemia was highest among adults aged ≥65 years (25.5 per 100,000 population) followed by infants aged <1 year (15.8). The crude annual incidence was higher among males (9.4) than among females (8.0) and was approximately 2 times greater among blacks than among nonblacks (13.7 versus 5.8). Ninety-six percent of cases occurred in patients who were hospitalized at the time of or during the week after having a positive culture. One third of cases occurred in patients who had undergone a surgical procedure in the 90 days before the candidemia diagnosis, 77% occurred in patients who had received systemic antibiotics in the 14 days before the diagnosis, and 73% occurred in patients who had had a central venous catheter (CVC) in place within 2 days before the diagnosis. Ten percent were in patients who had used injection drugs in the past 12 months. The median time from admission to candidemia diagnosis was 5 days (interquartile range [IQR]: 0-16 days). Among 2,662 cases that were treated in adults aged >18 years, 34% were treated with fluconazole alone, 30% with echinocandins alone, and 34% with both. The all-cause, in-hospital case-fatality ratio was 25% for any time after admission; the all-cause in-hospital case-fatality ratio was 8% for <48 hours after a positive culture for Candida species. Candida albicans accounted for 39% of cases, followed by Candida glabrata (28%) and Candida parapsilosis (15%). Overall, 7% of isolates were resistant to fluconazole and 1.6% were resistant to echinocandins, with no clear trends in resistance over the 5-year surveillance period. INTERPRETATION Approximately nine out of 100,000 persons developed culture-positive candidemia annually in four U.S. sites. The youngest and oldest persons, men, and blacks had the highest incidences of candidemia. Patients with candidemia identified in the surveillance program had many of the typical risk factors for candidemia, including recent surgery, exposure to broad-spectrum antibiotics, and presence of a CVC. However, an unexpectedly high proportion of candidemia cases (10%) occurred in patients with a history of injection drug use (IDU), suggesting that IDU has become a common risk factor for candidemia. Deaths associated with candidemia remain high, with one in four cases resulting in death during hospitalization. PUBLIC HEALTH ACTION Active surveillance for candidemia yielded important information about the disease incidence and death rate and persons at greatest risk. The surveillance was expanded to nine sites in 2017, which will improve understanding of the geographic variability in candidemia incidence and associated clinical and demographic features. This surveillance will help monitor incidence trends, track emergence of resistance and species distribution, monitor changes in underlying conditions and predisposing factors, assess trends in antifungal treatment and outcomes, and be helpful for those developing prevention efforts. IDU has emerged as an important risk factor for candidemia, and interventions to prevent invasive fungal infections in this population are needed. Surveillance data documenting that approximately two thirds of candidemia cases were caused by species other than C. albicans, which are generally associated with greater antifungal resistance than C. albicans, and the presence of substantial fluconazole resistance supports 2016 clinical guidelines recommending a switch from fluconazole to echinocandins as the initial treatment for candidemia in most patients.
Collapse
|
3
|
Benedict K, Roy M, Kabbani S, Anderson EJ, Farley MM, Harb S, Harrison LH, Bonner L, Wadu VL, Marceaux K, Hollick R, Beldavs ZG, Zhang AY, Schaffner W, Graber CR, Derado G, Chiller TM, Lockhart SR, Vallabhaneni S. Neonatal and Pediatric Candidemia: Results From Population-Based Active Laboratory Surveillance in Four US Locations, 2009-2015. J Pediatric Infect Dis Soc 2018. [PMID: 29522195 DOI: 10.1093/jpids/piy009] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
INTRODUCTION Candida is a leading cause of healthcare-associated bloodstream infections in the United States. Infants and children have unique risk factors for candidemia, and the Candida species distribution in this group is different that among adults; however, candidemia epidemiology in this population has not been described recently. METHODS We conducted active population-based candidemia surveillance in 4 US metropolitan areas between 2009 and 2015. We calculated incidences among neonates (0-30 days old), infants (0-364 days old), and noninfant children (1-19 years old), documented their clinical features and antifungal drug resistance. RESULTS We identified 307 pediatric candidemia cases. Incidence trends varied according to site, but overall, the incidence in neonates decreased from 31.5 cases/100000 births in 2009 to 10.7 to 11.8 cases/100000 births between 2012 and 2015, the incidence in infants decreased from 52.1 cases/100000 in 2009 to 15.7 to 17.5 between 2012 and 2015, and the incidence in noninfant children decreased steadily from 1.8 cases/100000 in 2009 to 0.8 in 2014. Common underlying conditions were prematurity in neonates (78%), surgery in nonneonate infants (38%), and malignancy in noninfant children (28%). Most neonate cases were caused by C albicans (67%), whereas non-C. albicans species accounted for 60% of cases in nonneonate infants and noninfant children. Fluconazole and echinocandin resistance rates were low overall. Thirty-day crude mortality was 13%. CONCLUSIONS The incidence of candidemia among neonates and infants declined after 2009 but remained stable from 2012 to 2015. Antifungal drug resistance is uncommon. Reasons for the lack of recent declines in neonatal and infant candidemia deserve further exploration. In this article, we describe the epidemiology of candidemia in children in the United States and on the basis of data collected as part of US Centers for Disease Control and Prevention active population-based surveillance. Trends in incidence, clinical characteristics, species distribution, and resistance rates are presented.
Collapse
Affiliation(s)
- Kaitlin Benedict
- Mycotic Diseases Branch, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Monika Roy
- Mycotic Diseases Branch, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Sarah Kabbani
- Georgia Emerging Infections Program, Atlanta Veterans Affairs Medical Center, Atlanta Research and Education Foundation, and Emory University School of Medicine, Georgia
| | - Evan J Anderson
- Georgia Emerging Infections Program, Atlanta Veterans Affairs Medical Center, Atlanta Research and Education Foundation, and Emory University School of Medicine, Georgia
| | - Monica M Farley
- Georgia Emerging Infections Program, Atlanta Veterans Affairs Medical Center, Atlanta Research and Education Foundation, and Emory University School of Medicine, Georgia
| | - Sasha Harb
- Georgia Emerging Infections Program, Atlanta Veterans Affairs Medical Center, Atlanta Research and Education Foundation, and Emory University School of Medicine, Georgia
| | - Lee H Harrison
- Maryland Emerging Infections Program, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Lindsay Bonner
- Maryland Emerging Infections Program, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Vijitha Lahanda Wadu
- Maryland Emerging Infections Program, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Kaytlyn Marceaux
- Maryland Emerging Infections Program, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Rosemary Hollick
- Maryland Emerging Infections Program, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Zintar G Beldavs
- Acute and Communicable Disease Prevention, Oregon Health Authority, Portland
| | - Alexia Y Zhang
- Acute and Communicable Disease Prevention, Oregon Health Authority, Portland
| | | | | | - Gordana Derado
- Mycotic Diseases Branch, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Tom M Chiller
- Mycotic Diseases Branch, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Shawn R Lockhart
- Mycotic Diseases Branch, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Snigdha Vallabhaneni
- Mycotic Diseases Branch, Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| |
Collapse
|
4
|
Lockhart SR, Etienne KA, Vallabhaneni S, Farooqi J, Chowdhary A, Govender NP, Colombo AL, Calvo B, Cuomo CA, Desjardins CA, Berkow EL, Castanheira M, Magobo RE, Jabeen K, Asghar RJ, Meis JF, Jackson B, Chiller T, Litvintseva AP. Simultaneous Emergence of Multidrug-Resistant Candida auris on 3 Continents Confirmed by Whole-Genome Sequencing and Epidemiological Analyses. Clin Infect Dis 2016; 64:134-140. [PMID: 27988485 DOI: 10.1093/cid/ciw691] [Citation(s) in RCA: 968] [Impact Index Per Article: 121.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 10/14/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Candida auris, a multidrug-resistant yeast that causes invasive infections, was first described in 2009 in Japan and has since been reported from several countries. METHODS To understand the global emergence and epidemiology of C. auris, we obtained isolates from 54 patients with C. auris infection from Pakistan, India, South Africa, and Venezuela during 2012-2015 and the type specimen from Japan. Patient information was available for 41 of the isolates. We conducted antifungal susceptibility testing and whole-genome sequencing (WGS). RESULTS Available clinical information revealed that 41% of patients had diabetes mellitus, 51% had undergone recent surgery, 73% had a central venous catheter, and 41% were receiving systemic antifungal therapy when C. auris was isolated. The median time from admission to infection was 19 days (interquartile range, 9-36 days), 61% of patients had bloodstream infection, and 59% died. Using stringent break points, 93% of isolates were resistant to fluconazole, 35% to amphotericin B, and 7% to echinocandins; 41% were resistant to 2 antifungal classes and 4% were resistant to 3 classes. WGS demonstrated that isolates were grouped into unique clades by geographic region. Clades were separated by thousands of single-nucleotide polymorphisms, but within each clade isolates were clonal. Different mutations in ERG11 were associated with azole resistance in each geographic clade. CONCLUSIONS C. auris is an emerging healthcare-associated pathogen associated with high mortality. Treatment options are limited, due to antifungal resistance. WGS analysis suggests nearly simultaneous, and recent, independent emergence of different clonal populations on 3 continents. Risk factors and transmission mechanisms need to be elucidated to guide control measures.
Collapse
Affiliation(s)
- Shawn R Lockhart
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia;
| | - Kizee A Etienne
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Snigdha Vallabhaneni
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Joveria Farooqi
- Department of Pathology and Laboratory Medicine, Aga Khan University, Karachi, and
| | - Anuradha Chowdhary
- Department of Medical Mycology, Vallabhbhai Patel Chest Institute, University of Delhi, India
| | - Nelesh P Govender
- National Institute for Communicable Diseases-Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service, Johannesburg, South Africa
| | | | - Belinda Calvo
- Department of Infectious Diseases, School of Medicine, Universidad del Zulia, Maracaibo, Venezuela
| | | | | | - Elizabeth L Berkow
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | | | - Rindidzani E Magobo
- National Institute for Communicable Diseases-Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service, Johannesburg, South Africa
| | - Kauser Jabeen
- Department of Pathology and Laboratory Medicine, Aga Khan University, Karachi, and
| | - Rana J Asghar
- Centers for Disease Control and Prevention Field Epidemiology and Laboratory Training Program, Islamabad, Pakistan
| | - Jacques F Meis
- Department of Medical Microbiology and Infectious Diseases, Canisius-Wilhelmina Hospital, and.,Department of Medical Microbiology, Radboudumc, Nijmegen, The Netherlands
| | - Brendan Jackson
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Tom Chiller
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | | |
Collapse
|
5
|
Naicker SD, Govender N, Patel J, Zietsman IL, Wadula J, Coovadia Y, Kularatne R, Seetharam S, Govender NP. Comparison of species-level identification and antifungal susceptibility results from diagnostic and reference laboratories for bloodstream Candida surveillance isolates, South Africa, 2009-2010. Med Mycol 2016; 54:816-24. [PMID: 27335055 DOI: 10.1093/mmy/myw046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 04/18/2016] [Indexed: 11/13/2022] Open
Abstract
From February 2009 through August 2010, we compared species-level identification of bloodstream Candida isolates and susceptibility to fluconazole, voriconazole, and caspofungin between diagnostic and reference South African laboratories during national surveillance for candidemia. Diagnostic laboratories identified isolates to genus/species level and performed antifungal susceptibility testing, as indicated. At a reference laboratory, viable Candida isolates were identified to species-level using automated systems, biochemical tests, or DNA sequencing; broth dilution susceptibility testing was performed. Categorical agreement (CA) was calculated for susceptibility results of isolates with concordant species identification. Overall, 2172 incident cases were detected, 773 (36%) by surveillance audit. The Vitek 2 YST system (bioMérieux Inc, Marcy l'Etoile, France) was used for identification (360/863, 42%) and susceptibility testing (198/473, 42%) of a large proportion of isolates. For the five most common species (n = 1181), species-level identification was identical in the majority of cases (Candida albicans: 98% (507/517); Candida parapsilosis: 92% (450/488); Candida glabrata: 89% (89/100); Candida tropicalis: 91% (49/54), and Candida krusei: 86% (19/22)). However, diagnostic laboratories were significantly less likely to correctly identify Candida species other than C. albicans versus C. albicans (607/664, 91% vs. 507/517, 98%; P < .001). Susceptibility data were compared for isolates belonging to the five most common species and fluconazole, voriconazole, and caspofungin in 860, 580, and 99 cases, respectively. Diagnostic laboratories significantly under-reported fluconazole resistance in C. parapsilosis (225/393, 57% vs. 239/393, 61%; P < .001) but over-reported fluconazole non-susceptibility in C. albicans (36/362, 10% vs. 3/362, 0.8%; P < .001). Diagnostic laboratories were less likely to correctly identify Candida species other than C. albicans, under-reported fluconazole resistance for C. parapsilosis and over-reported fluconazole resistance for C. albicans.
Collapse
Affiliation(s)
- Serisha D Naicker
- National Institute for Communicable Diseases (NICD) - Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service (NHLS), Johannesburg
| | - Nevashan Govender
- National Institute for Communicable Diseases (NICD) - Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service (NHLS), Johannesburg
| | - Jaymati Patel
- National Institute for Communicable Diseases (NICD) - Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service (NHLS), Johannesburg
| | | | - Jeannette Wadula
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa Chris Hani Baragwanath Hospital, National Health Laboratory Service, Johannesburg, South Africa
| | - Yacoob Coovadia
- Inkosi Albert Luthuli Hospital, National Health Laboratory Service and Faculty of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Ranmini Kularatne
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa Helen Joseph Hospital, National Health Laboratory Service, Johannesburg, South Africa
| | - Sharona Seetharam
- Chris Hani Baragwanath Hospital, National Health Laboratory Service, Johannesburg, South Africa
| | - Nelesh P Govender
- National Institute for Communicable Diseases (NICD) - Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service (NHLS), Johannesburg Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | | |
Collapse
|
6
|
Govender NP, Patel J, Magobo RE, Naicker S, Wadula J, Whitelaw A, Coovadia Y, Kularatne R, Govind C, Lockhart SR, Zietsman IL. Emergence of azole-resistant Candida parapsilosis causing bloodstream infection: results from laboratory-based sentinel surveillance in South Africa. J Antimicrob Chemother 2016; 71:1994-2004. [PMID: 27125552 DOI: 10.1093/jac/dkw091] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 02/29/2016] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVES To compare Candida species distribution and antifungal susceptibility at South African public- and private-sector hospitals. METHODS From February 2009 through to August 2010, laboratory-based surveillance for candidaemia was undertaken at 11 public-sector hospitals and >85 private-sector hospitals across South Africa. A case was defined as a patient of any age admitted to a sentinel hospital with isolation of Candida species from blood culture. Viable isolates were identified and tested for antifungal susceptibility at a reference laboratory. Demographic and limited clinical data were abstracted from laboratory records. RESULTS In total, 2172 cases of candidaemia were detected. Among patients with available data, almost two-thirds were critically ill (719/1138, 63%). On multivariable analysis, neonates [adjusted OR (aOR), 2.2; 95% CI, 1.5-3.1; P < 0.001] and patients diagnosed in Gauteng province (aOR, 1.9; 95% CI, 1.3-2.7; P < 0.001) or in the private sector (aOR, 1.9; 95% CI, 1.2-3.2; P = 0.008) were significantly more likely to be infected with Candida parapsilosis than any other Candida species. Of 531 C. parapsilosis isolates, only 199 (37%) were susceptible to fluconazole and voriconazole; 44% (123/282) of fluconazole-resistant isolates were voriconazole cross-resistant. Factors associated with fluconazole non-susceptible C. parapsilosis infection on multivariable analysis included diagnosis in Gauteng province (aOR, 4.2; 95% CI, 2.7-6.7; P < 0.001), an ICU (aOR, 2.3; 95% CI, 1.5-3.6; P < 0.001) or the private sector (aOR, 2.2; 95% CI, 1.4-3.5; P < 0.001). CONCLUSIONS The dominance of triazole non-susceptible C. parapsilosis limits the choice of antifungal agents for management of candidaemia among critically ill neonates, children and adults in resource-limited South African hospitals.
Collapse
Affiliation(s)
- Nelesh P Govender
- National Institute for Communicable Diseases-Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service, Johannesburg, South Africa Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Jaymati Patel
- National Institute for Communicable Diseases-Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service, Johannesburg, South Africa
| | - Rindidzani E Magobo
- National Institute for Communicable Diseases-Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service, Johannesburg, South Africa Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Serisha Naicker
- National Institute for Communicable Diseases-Centre for Opportunistic, Tropical and Hospital Infections, a Division of the National Health Laboratory Service, Johannesburg, South Africa
| | - Jeannette Wadula
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa Chris Hani Baragwanath Hospital, National Health Laboratory Service, Johannesburg, South Africa
| | - Andrew Whitelaw
- Tygerberg Hospital, National Health Laboratory Service and Faculty of Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Yacoob Coovadia
- Inkosi Albert Luthuli Hospital, National Health Laboratory Service and Faculty of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Ranmini Kularatne
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa Helen Joseph Hospital, National Health Laboratory Service, Johannesburg, South Africa
| | | | - Shawn R Lockhart
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Inge L Zietsman
- Ampath National Laboratory Service, Johannesburg, South Africa
| | | |
Collapse
|
7
|
Heslop OD, De Ceulaer K, Rainford L, M Nicholson A. A case of Candida orthopsilosis associated septic arthritis in a patient with Systemic Lupus Erythematosus (SLE). Med Mycol Case Rep 2014; 7:1-3. [PMID: 27330938 PMCID: PMC4909869 DOI: 10.1016/j.mmcr.2014.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 10/29/2014] [Accepted: 11/03/2014] [Indexed: 12/04/2022] Open
Abstract
We report a case of persistent Candida orthopsilosis associated septic arthritis. Repeated isolation of C. orthopsilosis from tissue and joint fluid was confirmed by identification of the ITS region of the rRNA gene using a Candida-Specific Luminex based assay and gene sequencing of the D1/D2 regions. This was the first case of C. orthopsilosis associated septic arthritis reported in Jamaica and in the literature.
Collapse
Affiliation(s)
- Orville D Heslop
- Depatrtment of Microbiology, University of the West Indies, Mona, Kingston7, Jamaica
| | - Karel De Ceulaer
- University Hospital of the West Indies, Mona, Kingston 7, Jamaica
| | - Lois Rainford
- Depatrtment of Microbiology, University of the West Indies, Mona, Kingston7, Jamaica
| | - Alison M Nicholson
- Depatrtment of Microbiology, University of the West Indies, Mona, Kingston7, Jamaica
| |
Collapse
|
8
|
Role of FKS Mutations in Candida glabrata: MIC values, echinocandin resistance, and multidrug resistance. Antimicrob Agents Chemother 2014; 58:4690-6. [PMID: 24890592 DOI: 10.1128/aac.03255-14] [Citation(s) in RCA: 162] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Candida glabrata is the second leading cause of candidemia in U.S. hospitals. Current guidelines suggest that an echinocandin be used as the primary therapy for the treatment of C. glabrata disease due to the high rate of resistance to fluconazole. Recent case reports indicate that C. glabrata resistance to echinocandins may be increasing. We performed susceptibility testing on 1,380 isolates of C. glabrata collected between 2008 and 2013 from four U.S. cities, Atlanta, Baltimore, Knoxville, and Portland. Our analysis showed that 3.1%, 3.3%, and 3.6% of the isolates were resistant to anidulafungin, caspofungin, and micafungin, respectively. We screened 1,032 of these isolates, including all 77 that had either a resistant or intermediate MIC value with respect to at least one echinocandin, for mutations in the hot spot regions of FKS1 and FKS2, the major mechanism of echinocandin resistance. Fifty-one isolates were identified with hot spot mutations, 16 in FKS1 and 35 in FKS2. All of the isolates with an FKS mutation except one were resistant to at least one echinocandin by susceptibility testing. Of the isolates resistant to at least one echinocandin, 36% were also resistant to fluconazole. Echinocandin resistance among U.S. C. glabrata isolates is a concern, especially in light of the fact that one-third of those isolates may be multidrug resistant. Further monitoring of U.S. C. glabrata isolates for echinocandin resistance is warranted.
Collapse
|
9
|
Development of a Luminex-based multiplex assay for detection of mutations conferring resistance to Echinocandins in Candida glabrata. J Clin Microbiol 2013; 52:790-5. [PMID: 24353003 DOI: 10.1128/jcm.03378-13] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Echinocandins are the recommended treatment for invasive candidiasis due to Candida glabrata. Resistance to echinocandins is known to be caused by nonsynonymous mutations in the hot spot-1 (HS1) regions of the FKS1 and FKS2 genes, which encode a subunit of the β-1,3-glucan synthase, the target of echinocandins. Here, we describe the development of a microsphere-based assay using Luminex MagPix technology to identify mutations in the FKS1 HS1 and FKS2 HS1 domains, which confer in vitro echinocandin resistance in C. glabrata isolates. The assay is rapid and can be performed with high throughput. The assay was validated using 102 isolates that had FKS1 HS1 and FKS2 HS1 domains previously characterized by DNA sequencing. The assay was 100% concordant with DNA sequencing results. The assay was then used for high-throughput screening of 1,032 C. glabrata surveillance isolates. Sixteen new isolates with mutations, including a mutation that was new to our collection (del659F), were identified. This assay provides a rapid and cost-effective way to screen C. glabrata isolates for echinocandin resistance.
Collapse
|
10
|
Gómez BL. Molecular diagnosis of endemic and invasive mycoses: advances and challenges. Rev Iberoam Micol 2013; 31:35-41. [PMID: 24252827 DOI: 10.1016/j.riam.2013.09.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 09/27/2013] [Indexed: 10/26/2022] Open
Abstract
The diagnosis of endemic and invasive fungal disease remains challenging. Molecular techniques for identification of fungi now play a significant and growing role in clinical mycology and offer distinct advantages as they are faster, more sensitive and more specific. The aim of this mini-review is to provide an overview of the state of the art of molecular diagnosis of endemic and invasive fungal diseases, and to emphasize the challenges and current need for standardization of the different methods. The European Aspergillus PCR Initiative (EAPCRI) has made significant progress in developing a standard for Aspergillus polymerase chain reaction (PCR), but recognizes that the process will not be finished until clinical utility has been established in formal and extensive clinical trials. Similar efforts should be implemented for the diagnosis of the other mycoses in order to fully validate the current methods or reinforce the need to design new ones. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).
Collapse
Affiliation(s)
- Beatriz L Gómez
- School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia; Medical and Experimental Mycology Group, Corporación para Investigaciones Biológicas (CIB), Medellin, Colombia.
| |
Collapse
|
11
|
Neppelenbroek KH, Seó RS, Urban VM, Silva S, Dovigo LN, Jorge JH, Campanha NH. Identification of
Candida
species in the clinical laboratory: a review of conventional, commercial, and molecular techniques. Oral Dis 2013; 20:329-44. [DOI: 10.1111/odi.12123] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 03/25/2013] [Accepted: 04/15/2013] [Indexed: 01/24/2023]
Affiliation(s)
- KH Neppelenbroek
- Department of Prosthodontics Bauru Dental School University of São Paulo‐USP Bauru São PauloBrazil
| | - RS Seó
- Department of Prosthodontics Varzea Grande School of Dentistry Varzea Grande Mato GrossoBrazil
| | - VM Urban
- Department of Dentistry Ponta Grossa State University‐UEPG Ponta Grossa Paraná Brazil
| | - S Silva
- Department of Biological Engineering Institute for Biotechnology and Bioengineering University of Minho Braga Portugal
| | - LN Dovigo
- Department of Social Dentistry Araraquara Dental School UNESP – Univ. Estadual Paulista Araraquara São PauloBrazil
| | - JH Jorge
- Department of Dental Materials and Prosthodontics Araraquara Dental School UNESP – Univ. Estadual Paulista Araraquara São Paulo Brazil
| | - NH Campanha
- Department of Dentistry Ponta Grossa State University‐UEPG Ponta Grossa Paraná Brazil
| |
Collapse
|
12
|
Lockhart SR, Iqbal N, Cleveland AA, Farley MM, Harrison LH, Bolden CB, Baughman W, Stein B, Hollick R, Park BJ, Chiller T. Species identification and antifungal susceptibility testing of Candida bloodstream isolates from population-based surveillance studies in two U.S. cities from 2008 to 2011. J Clin Microbiol 2012; 50:3435-42. [PMID: 22875889 PMCID: PMC3486211 DOI: 10.1128/jcm.01283-12] [Citation(s) in RCA: 206] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 08/01/2012] [Indexed: 01/03/2023] Open
Abstract
Between 2008 and 2011, population-based candidemia surveillance was conducted in Atlanta, GA, and Baltimore, MD. Surveillance had been previously performed in Atlanta in 1992 to 1993 and in Baltimore in 1998 to 2000, making this the first population-based candidemia surveillance conducted over multiple time points in the United States. From 2,675 identified cases of candidemia in the current surveillance, 2,329 Candida isolates were collected. Candida albicans no longer comprised the majority of isolates but remained the most frequently isolated species (38%), followed by Candida glabrata (29%), Candida parapsilosis (17%), and Candida tropicalis (10%). The species distribution has changed over time; in both Atlanta and Baltimore the proportion of C. albicans isolates decreased, and the proportion of C. glabrata isolates increased, while the proportion of C. parapsilosis isolates increased in Baltimore only. There were 98 multispecies episodes, with C. albicans and C. glabrata the most frequently encountered combination. The new species-specific CLSI Candida MIC breakpoints were applied to these data. With the exception of C. glabrata (11.9% resistant), resistance to fluconazole was very low (2.3% of isolates for C. albicans, 6.2% for C. tropicalis, and 4.1% for C. parapsilosis). There was no change in the proportion of fluconazole resistance between surveillance periods. Overall echinocandin resistance was low (1% of isolates) but was higher for C. glabrata isolates, ranging from 2.1% isolates resistant to caspofungin in Baltimore to 3.1% isolates resistant to anidulafungin in Atlanta. Given the increase at both sites and the higher echinocandin resistance, C. glabrata should be closely monitored in future surveillance.
Collapse
Affiliation(s)
- Shawn R Lockhart
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Farooqi JQ, Jabeen K, Saeed N, Iqbal N, Malik B, Lockhart SR, Zafar A, Brandt ME, Hasan R. Invasive candidiasis in Pakistan: clinical characteristics, species distribution and antifungal susceptibility. J Med Microbiol 2012; 62:259-268. [PMID: 23105021 DOI: 10.1099/jmm.0.048785-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
This study reports for the first time, to our knowledge, descriptive epidemiological data for 188 invasive Candida isolates from Pakistan, including species identification and antifungal susceptibility against fluconazole, itraconazole, voriconazole, caspofungin, micafungin, anidulafungin and amphotericin. Risk factors for invasive candidiasis (IC) were determined for 96 patients from Karachi, Pakistan. In adults and neonates, Candida tropicalis (38 and 36 %, respectively) was the most common species, followed in adults by Candida parapsilosis (17.8 %), Candida glabrata (15.9 %) and Candida albicans (12.3 %). C. albicans (21 %) was the second most common in neonates. In children, C. albicans (31.9 %), C. tropicalis (26.4 %) and C. parapsilosis (19.4 %) were the most common. C. albicans IC was significantly associated with paediatric age [crude odds ratio (COR) 3.46, 95 % confidence interval (CI) 1.63-7.32]. Rare species made up 17.5 % of the total isolates studied. Resistance to fluconazole was seen in C. glabrata (15 .0%) and Candida krusei (100 .0%). Only one isolate (C. glabrata) was resistant to all three echinocandins. Low MICs of fluconazole for 98 % (184/188) of isolates tested support its continued use as an empiric therapy for IC. Non-C. albicans IC was associated with the use of β-lactam inhibitor combinations (COR 3.16, 95 % CI 1.05-9.57). Use of healthcare devices was documented in 85.4 % of IC patients, whilst 75 .0% had been admitted to special care units. Surprisingly, 66.7 % of patients with IC were not obviously immunosuppressed. The high frequency of modifiable risk factors in this population indicates that candidaemia can be reduced with stringent antibiotic and infection control measures. These data will be useful for empiric selection of antifungals in Karachi, and contribute to global assessments of antifungal resistance.
Collapse
Affiliation(s)
- J Q Farooqi
- Department of Pathology Microbiology, Aga Khan Hospital Karachi, Pakistan
| | - K Jabeen
- Department of Pathology Microbiology, Aga Khan Hospital Karachi, Pakistan
| | - N Saeed
- Department of Pathology Microbiology, Aga Khan Hospital Karachi, Pakistan
| | - N Iqbal
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - B Malik
- Department of Pathology Microbiology, Aga Khan Hospital Karachi, Pakistan
| | - S R Lockhart
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - A Zafar
- Department of Pathology Microbiology, Aga Khan Hospital Karachi, Pakistan
| | - M E Brandt
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - R Hasan
- Department of Pathology Microbiology, Aga Khan Hospital Karachi, Pakistan
| |
Collapse
|
14
|
Liao MH, Lin JF, Li SY. Application of a multiplex suspension array for rapid and simultaneous identification of clinically important mold pathogens. Mol Cell Probes 2012; 26:188-93. [DOI: 10.1016/j.mcp.2012.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 06/14/2012] [Accepted: 06/25/2012] [Indexed: 11/29/2022]
|
15
|
Cleveland AA, Farley MM, Harrison LH, Stein B, Hollick R, Lockhart SR, Magill SS, Derado G, Park BJ, Chiller TM. Changes in incidence and antifungal drug resistance in candidemia: results from population-based laboratory surveillance in Atlanta and Baltimore, 2008-2011. Clin Infect Dis 2012; 55:1352-61. [PMID: 22893576 DOI: 10.1093/cid/cis697] [Citation(s) in RCA: 265] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Candidemia is common and associated with high morbidity and mortality; changes in population-based incidence rates have not been reported. METHODS We conducted active, population-based surveillance in metropolitan Atlanta, Georgia, and Baltimore City/County, Maryland (combined population 5.2 million), during 2008-2011. We calculated candidemia incidence and antifungal drug resistance compared with prior surveillance (Atlanta, 1992-1993; Baltimore, 1998-2000). RESULTS We identified 2675 cases of candidemia with 2329 isolates during 3 years of surveillance. Mean annual crude incidence per 100 000 person-years was 13.3 in Atlanta and 26.2 in Baltimore. Rates were highest among adults aged ≥65 years (Atlanta, 59.1; Baltimore, 72.4) and infants (aged <1 year; Atlanta, 34.3; Baltimore, 46.2). In both locations compared with prior surveillance, adjusted incidence significantly declined for infants of both black and white race (Atlanta: black risk ratio [RR], 0.26 [95% confidence interval {CI}, .17-.38]; white RR: 0.19 [95% CI, .12-.29]; Baltimore: black RR, 0.38 [95% CI, .22-.64]; white RR: 0.51 [95% CI: .29-.90]). Prevalence of fluconazole resistance (7%) was unchanged compared with prior surveillance; 32 (1%) isolates were echinocandin-resistant, and 9 (8 Candida glabrata) were multidrug resistant to both fluconazole and an echinocandin. CONCLUSIONS We describe marked shifts in candidemia epidemiology over the past 2 decades. Adults aged ≥65 years replaced infants as the highest incidence group; adjusted incidence has declined significantly in infants. Use of antifungal prophylaxis, improvements in infection control, or changes in catheter insertion practices may be contributing to these declines. Further surveillance for antifungal resistance and efforts to determine effective prevention strategies are needed.
Collapse
Affiliation(s)
- Angela Ahlquist Cleveland
- Mycotic Diseases Branch, Division of Foodborne, Waterborne and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Simultaneous detection of seven enteric viruses associated with acute gastroenteritis by a multiplexed Luminex-based assay. J Clin Microbiol 2012; 50:2384-9. [PMID: 22518865 DOI: 10.1128/jcm.06790-11] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rapid and broad diagnostic methods are needed for the identification of viral agents of gastroenteritis. In this study, we used Luminex xMAP technology to develop a multiplexed assay for the simultaneous identification of major enteric viral pathogens, including rotavirus A (RVA), noroviruses (NoVs) (including genogroups GI and GII), sapoviruses (SaV), human astrovirus (HAstV), enteric adenoviruses (EAds), and human bocavirus 2 (HBoV2). The analytical sensitivity allowed detection of 10(3) (EAds, HBoV2, and RVA) and 10(4) (NoV GI and GII, SaV, and HAstV) copies per reaction mixture. Compared to conventional PCR, the Luminex-based assay yielded greater than 75% sensitivity and 97% specificity for each virus, and the kappa correlation for detection of all viruses ranged from 0.75 to 1.00. In conclusion, this multiplexed Luminex-based assay provides a potentially rapid, high-throughput, and maneuverable diagnostic tool for major viral pathogens associated with gastroenteritis.
Collapse
|
17
|
Kourkoumpetis TK, Fuchs BB, Coleman JJ, Desalermos A, Mylonakis E. Polymerase chain reaction-based assays for the diagnosis of invasive fungal infections. Clin Infect Dis 2012; 54:1322-31. [PMID: 22362884 DOI: 10.1093/cid/cis132] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Currently accepted fungal diagnostic techniques, such as culture, biopsy, and serology, lack rapidity and efficiency. Newer diagnostic methods, such as polymerase chain reaction (PCR)-based assays, have the potential to improve fungal diagnostics in a faster, more sensitive, and specific manner. Preliminary data indicate that, when PCR-based fungal diagnostic assays guide antifungal therapy, they may lower patient mortality and decrease unnecessary antifungal treatment, improving treatment-associated costs and avoiding toxicity. Moreover, newer PCR techniques can identify antifungal resistance DNA loci, but the clinical correlation between those loci and clinical failure has to be studied further. In addition, future studies need to focus on the implementation of PCR techniques in clinical decision making and on combining them with other diagnostic tests. A consensus on the standardization of PCR techniques, along with validation from large prospective studies, is necessary to allow widespread adoption of these assays.
Collapse
Affiliation(s)
- Themistoklis K Kourkoumpetis
- Department of Medicine, Infectious Disease Division, Massachusetts General Hospital, Harvard Medical School, Boston 02214, USA
| | | | | | | | | |
Collapse
|
18
|
Abstract
A multiplex-PCR Luminex xMAP bead probe fluid array using xTAG analyte-specific reagents (multiplex xTAG fungal ASR assay) was employed for detection of clinically significant Candida species, Cryptococcus neoformans, Histoplasma capsulatum, and Blastomyces dermatitidis from blood cultures. We tested 132 blood cultures negative (n = 10) or positive (n = 97) for yeasts and/or bacteria (n = 25). The assay showed sensitivity and specificity of 100% and 99%, respectively. The xTAG fungal ASR assay is a rapid assay that allows simultaneous identification of multiple yeast species.
Collapse
|
19
|
Do hospital microbiology laboratories still need to distinguish Candida albicans from Candida dubliniensis? J Clin Microbiol 2011; 49:4415. [PMID: 21998427 DOI: 10.1128/jcm.05923-11] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
20
|
Lott TJ, Frade JP, Lyon GM, Iqbal N, Lockhart SR. Bloodstream and non-invasive isolates of Candida glabrata have similar population structures and fluconazole susceptibilities. Med Mycol 2011; 50:136-42. [PMID: 21838617 DOI: 10.3109/13693786.2011.592153] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We have compared multilocus sequence typing (MLST) and fluconazole susceptibility profiles of Candida glabrata bloodstream isolates obtained during active, population-based surveillance to those obtained from non-sterile sites of individuals with no evidence of fungal disease (i.e., non-invasive isolates) in the same US city during an overlapping time period. In each of the two populations, different proportions of the same six major sequence types (STs) encompassed 82% of the isolates. One ST was more prevalent in the candidemia population and two other STs were more prevalent in the non-invasive population, but the overall allelic frequencies within the groups suggested little, if any, genotypic diversity between them. Fluconazole susceptibility profiles of isolates from the patients in the two groups were not significantly different and were not associated with a particular sequence type. Our results support the hypothesis that C. glabrata strains causing bloodstream infections are genetically indistinguishable from those normally residing in/on the host, suggesting that relative pathogenicity may be closely tied to commensalism.
Collapse
Affiliation(s)
- Timothy J Lott
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, Mailstop G-11, Atlanta, GA 30333, USA
| | | | | | | | | |
Collapse
|
21
|
Gleason LU, Burton RS. High-throughput molecular identification of fish eggs using multiplex suspension bead arrays. Mol Ecol Resour 2011; 12:57-66. [PMID: 21831139 DOI: 10.1111/j.1755-0998.2011.03059.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The location and abundance of fish eggs provide information concerning the timing and location of spawning activities and can provide fishery-independent estimates of spawning biomass. However, the full value of egg and larval surveys is severely restricted because many species' eggs and larvae are morphologically similar, making species-level identification difficult. Recent efforts have shown that nearly all species of fish may be identified by mitochondrial DNA (mtDNA) sequences (e.g. via 'DNA barcoding'). By taking advantage of a DNA barcode database, we have developed oligonucleotide probes for 23 marine fish species that produce pelagic eggs commonly found in California waters. Probes were coupled to fluorescent microspheres to create a suspension bead array. Biotin-labelled primers were used to amplify the mitochondrial cytochrome oxidase subunit I (COI) and 16S ribosomal rRNA genes from individual fish eggs. The amplicons were then hybridized to the bead array, and after the addition of a reporter fluorophore, samples were analysed by flow cytometry with Luminex 100 instrumentation. Probes specifically targeted eggs that are abundant and/or from morphologically indistinguishable species pairs. Results showed that the 33 different probes designed for this study accurately identified all samples when PCR was successful. Suspension bead arrays have a number of benefits over other methods of molecular identification; these arrays permit high multiplexing, simple addition of new probes, high throughput and lower cost than DNA sequencing. The increasing availability of DNA barcode data for numerous fish faunas worldwide suggests that bead arrays could be developed and widely used for fish egg, larval and tissue identifications.
Collapse
Affiliation(s)
- Lani U Gleason
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093-0202, USA.
| | | |
Collapse
|
22
|
Ando A, Shigenari A, Ota M, Sada M, Kawata H, Azuma F, Kojima-Shibata C, Nakajoh M, Suzuki K, Uenishi H, Kulski JK, Inoko H. SLA-DRB1 and -DQB1 genotyping by the PCR-SSOP-Luminex method. ACTA ACUST UNITED AC 2011; 78:49-55. [PMID: 21506937 DOI: 10.1111/j.1399-0039.2011.01669.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A simple and novel genotyping method was developed to detect alleles at the swine leukocyte antigen (SLA)-DRB1 and -DQB1 class II loci by using polymerase chain reaction (PCR)-fluorescently labeled sequence-specific oligonucleotide probes (SSOPs) and Luminex 100 xMAP detection. The PCR-SSOP-Luminex method exhibited accuracy of 95% for both SLA-DRB1 and -DQB1 in 6 homozygous and 16 heterozygous pig samples as confirmed by sequencing the PCR products of the same samples. In addition, 12 low-resolution SLA class II haplotypes consisting of 7 and 9 DRB1 and DQB1 alleles were identified, respectively, in one population of 283 Landrace pigs. This genotyping method facilitates the rapid and accurate identification of two- or four-digit alleles at the SLA-DRB1 and -DQB1 loci.
Collapse
Affiliation(s)
- A Ando
- Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Current awareness on yeast. Yeast 2010. [DOI: 10.1002/yea.1723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
|
24
|
FKS mutations and elevated echinocandin MIC values among Candida glabrata isolates from U.S. population-based surveillance. Antimicrob Agents Chemother 2010; 54:5042-7. [PMID: 20837754 DOI: 10.1128/aac.00836-10] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Candida glabrata is the second leading cause of candidemia in the United States. Its high-level resistance to triazole antifungal drugs has led to the increased use of the echinocandin class of antifungal agents for primary therapy of these infections. We monitored C. glabrata bloodstream isolates from a population-based surveillance study for elevated echinocandin MIC values (MICs of ≥0.25 μg/ml). From the 490 C. glabrata isolates that were screened, we identified 16 isolates with an elevated MIC value (2.9% of isolates from Atlanta and 2.0% of isolates from Baltimore) for one or more of the echinocandin drugs caspofungin, anidulafungin, and micafungin. All of the isolates with elevated MIC values had a mutation in the previously identified hot spot 1 of either the glucan synthase FKS1 (n = 2) or FKS2 (n = 14) gene. No mutations were detected in hot spot 2 of either FKS1 or FKS2. The predominant mutation was mutation of FKS2-encoded serine 663 to proline (S663P), found in 10 of the isolates with elevated echinocandin MICs. Two of the mutations, R631G for FKS1 and R665G for FKS2, have not been reported previously for C. glabrata. Multilocus sequence typing indicated that the predominance of the S663P mutation was not due to the clonal spread of a single sequence type. With a rising number of echinocandin therapy failures reported, it is important to continue to monitor rates of elevated echinocandin MIC values and the associated mutations.
Collapse
|