Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
1.
J Antimicrob Chemother ; 74(5): 1260-1268, 2019 05 01.
Article in English | MEDLINE | ID: mdl-30753525

ABSTRACT

OBJECTIVES: The emergence of fluconazole resistance in Candida parapsilosis healthcare-associated infections has recently been increasingly reported. Antifungal susceptibility profiles and mechanisms of fluconazole resistance in C. parapsilosis (n = 199) from nine hospitals in India collected over a period of 3 years were studied. Further, clonal transmission of fluconazole-resistant isolates in different hospitals was investigated. METHODS: Antifungal susceptibility testing of five azoles, amphotericin B and 5-flucytosine was performed by the CLSI microbroth dilution method. The azole target ERG11 gene was sequenced, and the significance of a novel ERG11 mutation in C. parapsilosis was determined using a gap-repair cloning approach in Saccharomyces cerevisiae. In addition, microsatellite analysis was performed to determine the clonal lineage of C. parapsilosis-resistant strains circulating among different hospitals. RESULTS: A total of 64 (32%) C. parapsilosis isolates were non-susceptible to fluconazole, which included resistant (n = 55; MIC >4 mg/L) and susceptible dose-dependent (n = 9) isolates. Of these 64 non-susceptible isolates, a novel K143R amino acid substitution was noted in 92%, and the remaining five isolates had the Y132F substitution. Elevated azole MICs (≥16-fold) were detected in S. cerevisiae upon expression of C. parapsilosis ERG11 alleles carrying Y132F or K143R substitutions. Two major clusters of non-susceptible isolates were circulating in seven Indian hospitals. CONCLUSIONS: We report a novel K143R amino acid substitution in ERG11p causing fluconazole resistance in C. parapsilosis. Fluconazole-non-susceptible C. parapsilosis isolates carrying the novel K143R amino acid substitution should be identified in clinical microbiology laboratories to prevent further clonal transmission.


Subject(s)
Antifungal Agents/pharmacology , Candida parapsilosis/drug effects , Candidiasis/microbiology , Drug Resistance, Fungal , Fluconazole/pharmacology , Amino Acid Substitution , Candida parapsilosis/genetics , Candidiasis/drug therapy , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Amplification , Humans , India/epidemiology , Microbial Sensitivity Tests , Microsatellite Repeats , Mutation , Phylogeny
2.
Article in English | MEDLINE | ID: mdl-29610199

ABSTRACT

Candida glabrata infections are increasing worldwide and exhibit greater rates of antifungal resistance than those with other species. DNA mismatch repair (MMR) gene deletions, such as msh2Δ, in C. glabrata resulting in a mutator phenotype have recently been reported to facilitate rapid acquisition of antifungal resistance. This study determined the antifungal susceptibility profiles of 210 C. glabrata isolates in 10 hospitals in India and investigated the impact of novel MSH2 polymorphisms on mutation potential. No echinocandin- or azole-resistant strains and no mutations in FKS hot spot regions were detected among the C. glabrata isolates, supporting our in vitro susceptibility testing results. CLSI antifungal susceptibility data showed that the MICs of anidulafungin (geometric mean [GM], 0.12 µg/ml) and micafungin (GM, 0.01 µg/ml) were lower and below the susceptibility breakpoint compared to that of caspofungin (CAS) (GM, 1.31 µg/ml). Interestingly, 69% of the C. glabrata strains sequenced contained six nonsynonymous mutations in MSH2, i.e., V239L and the novel mutations E459K, R847C, Q386K, T772S, and V239/D946E. Functional analysis of MSH2 mutations revealed that 49% of the tested strains (40/81) contained a partial loss-of-function MSH2 mutation. The novel MSH2 substitution Q386K produced higher frequencies of CAS-resistant colonies upon expression in the msh2Δ mutant. However, expression of two other novel MSH2 alleles, i.e., E459K or R847C, did not confer selection of resistant colonies, confirming that not all mutations in the MSH2 MMR pathway affect its function or generate a phenotype of resistance to antifungal drugs. The lack of drug resistance prevented any correlations from being drawn with respect to MSH2 genotype.


Subject(s)
Antifungal Agents/pharmacology , Azoles/pharmacology , Candida glabrata/drug effects , Candida glabrata/genetics , Drug Resistance, Fungal/genetics , Echinocandins/pharmacology , Anidulafungin/pharmacology , Candida glabrata/isolation & purification , Candidiasis/drug therapy , Candidiasis/microbiology , Caspofungin/pharmacology , DNA Mismatch Repair/genetics , Humans , India , Micafungin/pharmacology , Microbial Sensitivity Tests , Mutation/genetics
3.
J Antimicrob Chemother ; 73(4): 891-899, 2018 04 01.
Article in English | MEDLINE | ID: mdl-29325167

ABSTRACT

Background: Candida auris has emerged globally as an MDR nosocomial pathogen in ICU patients. Objectives: We studied the antifungal susceptibility of C. auris isolates (n = 350) from 10 hospitals in India collected over a period of 8 years. To investigate azole resistance, ERG11 gene sequencing and expression profiling was conducted. In addition, echinocandin resistance linked to mutations in the C. auris FKS1 gene was analysed. Methods: CLSI antifungal susceptibility testing of six azoles, amphotericin B, three echinocandins, terbinafine, 5-flucytosine and nystatin was conducted. Screening for amino acid substitutions in ERG11 and FKS1 was performed. Results: Overall, 90% of C. auris were fluconazole resistant (MICs 32 to ≥64 mg/L) and 2% and 8% were resistant to echinocandins (≥8 mg/L) and amphotericin B (≥2 mg/L), respectively. ERG11 sequences of C. auris exhibited amino acid substitutions Y132 and K143 in 77% (n = 34/44) of strains that were fluconazole resistant whereas WT genotypes, i.e. without substitutions at these positions, were observed in isolates with low fluconazole MICs (1-2 mg/L) suggesting that these substitutions confer a phenotype of resistance to fluconazole similar to that described for Candida albicans. No significant expression of ERG11 was observed, although expression was inducible in vitro with fluconazole exposure. Echinocandin resistance was linked to a novel mutation S639F in FKS1 hot spot region I. Conclusions: Overall, 25% and 13% of isolates were MDR and multi-azole resistant, respectively. The most common resistance combination was azoles and 5-flucytosine in 14% followed by azoles and amphotericin B in 7% and azoles and echinocandins in 2% of isolates.


Subject(s)
Antifungal Agents/pharmacology , Azoles/pharmacology , Candida/drug effects , Candidiasis/microbiology , Drug Resistance, Fungal , Echinocandins/pharmacology , Fungal Proteins/genetics , Candida/genetics , Candida/isolation & purification , Female , Gene Expression Profiling , Genotype , Humans , India , Male , Microbial Sensitivity Tests , Middle Aged , Mutation , Sequence Analysis, DNA
4.
PLoS One ; 10(5): e0122609, 2015.
Article in English | MEDLINE | ID: mdl-26024531

ABSTRACT

BACKGROUND: A drug-induced apoptosis assay has been developed to determine which chemotherapy drugs or regimens can produce higher cell killing in vitro. This study was done to determine if this assay could be performed in patients with recurrent or metastatic breast cancer patients, to characterize the patterns of drug-induced apoptosis, and to evaluate the clinical utility of the assay. A secondary goal was to correlate assay use with clinical outcomes. METHODS: In a prospective, non-blinded, multi institutional controlled trial, 30 evaluable patients with recurrent or metastatic breast cancer who were treated with chemotherapy had tumor samples submitted for the MiCK drug-induced apoptosis assay. After receiving results within 72 hours after biopsy, physicians could use the test to determine therapy (users), or elect to not use the test (non-users). RESULTS: The assay was able to characterize drug-induced apoptosis in tumor specimens from breast cancer patients and identified which drugs or combinations gave highest levels of apoptosis. Patterns of drug activity were also analyzed in triple negative breast cancer. Different drugs from a single class of agents often produced significantly different amounts of apoptosis. Physician frequently (73%) used the assay to help select chemotherapy treatments in patients, Patients whose physicians were users had a higher response (CR+PR) rate compared to non-users (38.1% vs 0%, p = 0.04) and a higher disease control (CR+PR+Stable) rate (81% vs 25%, p<0.01). Time to relapse was longer in users 7.4 mo compared to non-users 2.2 mo (p<0.01). CONCLUSIONS: The MiCK assay can be performed in breast cancer specimens, and results are often used by physicians in breast cancer patients with recurrent or metastatic disease. These results from a good laboratory phase II study can be the basis for a future larger prospective multicenter study to more definitively establish the value of the assay. TRIAL REGISTRATION: Clinicaltrials.gov NCT00901264.


Subject(s)
Antineoplastic Agents/therapeutic use , Biological Assay/methods , Breast Neoplasms/diagnosis , Breast Neoplasms/drug therapy , Aged , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Disease-Free Survival , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local , Treatment Outcome , Triple Negative Breast Neoplasms/diagnosis , Triple Negative Breast Neoplasms/drug therapy
5.
Diagn Pathol ; 6: 23, 2011 Mar 23.
Article in English | MEDLINE | ID: mdl-21429220

ABSTRACT

BACKGROUND: In recent years, a battery-powered bone marrow biopsy system was developed and cleared by the U.S. Food and Drug Administration to allow health care providers to access the bone marrow space quickly and efficiently. A multicenter randomized clinical trial was designed for adult patients to determine if the powered device had advantages over traditional manually-inserted needles in regard to length of procedure, patient pain, complications, user satisfaction, and pathological analysis of the specimens. METHODS: Adult patients requiring marrow sampling procedures were randomized for a Manual or Powered device. Visual Analog Scale (VAS) pain scores were captured immediately following the procedure and 1 and 7 days later. Procedure time was measured and core specimens were submitted to pathology for grading. RESULTS: Ten sites enrolled 102 patients into the study (Powered, n = 52; Manual, n = 50). Mean VAS scores for overall procedural pain were not significantly different between the arms (3.8 ± 2.8 for Powered, 3.5 ± 2.3 for Manual [p = 0.623]). A day later, more patients who underwent the Powered procedure were pain-free (67%) than those patients in the Manual group (33%; p = 0.003). One week later, there was no difference (83% for Powered patients; 76% for Manual patients.) Mean procedure time was 102.1 ± 86.4 seconds for the Powered group and 203.1 ± 149.5 seconds for the Manual group (p < 0.001). Pathology assessment was similar in specimen quality, but there was a significant difference in the specimen volume between the devices (Powered: 36.8 ± 21.2 mm3; Manual: 20.4 ± 9.0 mm3; p = 0.039). Two non-serious complications were experienced during Powered procedures (4%); but none during Manual procedures (p = 0.495). CONCLUSIONS: The results of this first trial provide evidence that the Powered device delivers larger-volume bone marrow specimens for pathology evaluation. In addition, bone marrow specimens were secured more rapidly and subjects experienced less intermediate term pain when the Powered device was employed. Further study is needed to determine if clinicians more experienced with the Powered device will be able to use it in a manner that significantly reduces needle insertion pain; and to compare a larger sample of pathology specimens obtained using the Powered device to those obtained using traditional manual biopsy needles.


Subject(s)
Bone Marrow Cells/pathology , Bone Marrow Examination/instrumentation , Specimen Handling/instrumentation , Aged , Biopsy , Biopsy, Needle/adverse effects , Bone Marrow Examination/methods , Equipment Design , Female , Humans , Male , Pain/etiology , Pain/physiopathology , Specimen Handling/methods
6.
Am J Hematol ; 86(1): 25-30, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21120861

ABSTRACT

Few studies have evaluated prognostic factors among patients with multiple myeloma (MM) since new therapies have become available. Monthly zoledronic acid (ZOL) has been incorporated into many treatment regimens to reduce skeletal-related events (SREs), but outcomes among patients receiving this bisphosphonate have not been well-defined. The aim of this retrospective study was to determine baseline and on-treatment prognostic factors in these patients. Data were collected from the date of diagnosis on 300 consecutive MM patients treated with ZOL. Median duration of ZOL was 18 months (range 1-121 months). The skeletal morbidity rate was 0.116 events per patient year. Five-year overall survival (OS) was 69%. Risk factors for shortened OS included SREs, increased serum creatinine, and International Staging System (ISS) Stage II or III. Thirty-four (11%) patients showed worsening renal function. In 28 of these patients, ZOL was discontinued and restarted in half of these patients following a brief delay. Only 5 of the 34 patients showed worsening of their renal function. Fourteen patients (4.7%) developed osteonecrosis of the jaw (ONJ). All patients with ONJ are in remission or with stable disease except one patient who died of a myocardial infarction while in remission. Only two patients showed some worsening of ONJ despite of ongoing monthly ZOL. Overall, these results suggest that skeletal complications are an important prognostic factor for MM. Although ONJ and renal deterioration may infrequently occur with ZOL, most patients do not experience worsening of these conditions with ongoing treatment with this bisphosphonate.


Subject(s)
Diphosphonates/adverse effects , Imidazoles/adverse effects , Jaw Diseases/chemically induced , Kidney Diseases/chemically induced , Multiple Myeloma/drug therapy , Adult , Aged , Aged, 80 and over , Diphosphonates/therapeutic use , Female , Humans , Imidazoles/therapeutic use , Jaw Diseases/pathology , Male , Middle Aged , Multiple Myeloma/pathology , Prognosis , Retrospective Studies , Risk Factors , Zoledronic Acid
7.
Clin Breast Cancer ; 7(10): 775-8, 2007 Oct.
Article in English | MEDLINE | ID: mdl-18021478

ABSTRACT

BACKGROUND: The frequency of aromatase inhibitor (AI)-associated arthralgia and/or bone pain in clinical practice is not known. PATIENTS AND METHODS: Fifty-six consecutive patients with breast cancer not on clinical trials who were receiving AIs in a clinical practice were interviewed regarding occurrence of worsening or new arthralgia and/or bone pain after starting AI therapy. The occurrence, character, severity, and resolution of pain were evaluated. RESULTS: Arthralgia and/or bone pain was reported in 61% of patients. It was severe in 30%, continuous in 41%, central in 50%, peripheral in 79%, and resulted in discontinuation of the drug in 20% of patients. Effective therapies in controlling pain were acetaminophen, 29%; nonsteroidal anti-inflammatory drugs, 50%; opiates, 18%, and glucosamine in 15% of patients. Despite this, 20% of patients discontinued AI therapy because of pain. CONCLUSION: Aromatase inhibitor-associated pain is more frequent in patients not in clinical trials than previously appreciated in clinical trials. Improved patient education is needed, and prompt therapeutic management of pain is required to ensure continued drug treatment and improved quality of life.


Subject(s)
Aromatase Inhibitors/adverse effects , Arthralgia/chemically induced , Arthralgia/epidemiology , Breast Neoplasms/drug therapy , Pain/chemically induced , Pain/epidemiology , Aromatase Inhibitors/therapeutic use , Bone and Bones/pathology , Clinical Trials as Topic , Female , Humans
SELECTION OF CITATIONS
SEARCH DETAIL
...