Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 45
Filter
1.
Ther Adv Infect Dis ; 11: 20499361241241199, 2024.
Article in English | MEDLINE | ID: mdl-38545450

ABSTRACT

The use of ibrutinib, a Bruton tyrosine kinase inhibitor, has been associated with invasive fungal infections (IFIs). We describe a case of Apophysomyces infection associated with long-term use of ibrutinib for the treatment of chronic lymphocytic leukemia as well as perform a literature review of Mucormycosis infections in patients on ibrutinib. Our review found that the onset of IFI can occur within months to years of starting tyrosine kinase inhibitors. These reports provide a more complete picture of the risk of IFI while patients are on ibrutinib. Our case also demonstrates the utility of molecular techniques in the diagnosis of IFI, as the diagnosis was made using 28S rDNA/internal transcribed spacer PCR.

2.
Access Microbiol ; 5(2): acmi000421, 2023.
Article in English | MEDLINE | ID: mdl-36919079

ABSTRACT

Members of the order Enterobacterales, including Escherichia coli , Klebsiella species and Enterobacter species, are important pathogens in healthcare-associated infections. Higher mortality has been reported from infections due to Klebsiella pneumoniae than from E. coli , but prior studies comparing Enterobacter aerogenes (recently renamed Klebsiella aerogenes ) bacteraemia and Enterobacter cloacae complex bacteraemia have yielded conflicting results regarding whether clinical outcomes differ. We found bacteraemia with K. aerogenes was independently associated with greater risk of 30-day mortality than bacteraemia with Enterobacter cloacae complex.

3.
Kidney Int Rep ; 5(7): 1014-1025, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32647759

ABSTRACT

INTRODUCTION: Patients with diabetes mellitus (DM) on hemodialysis (HD) may be particularly vulnerable to infections. METHODS: We used merged data from the United States Renal Data System and electronic health records data from a large US dialysis provider to retrospectively examine the association between glycemic control and infections in these patients. Adult patients with DM aged ≥18 years who initiated in-center maintenance HD treatment from 2006 to 2011 and survived >90 days were included. Quarterly mean time-averaged hemoglobin A1c (HbA1c) values were categorized into <5.5%, 5.5 to <6.5%, 6.5 to <7.5%, 7.5 to <8.5%, and ≥8.5%. We used Medicare claims to ascertain infection-related outcomes and the ESRD Death Notification to identify death from infectious cause. We used Cox proportional hazards models to estimate multivariable-adjusted hazard ratios and 95% confidence intervals (CIs) for the associations between time-averaged HbA1c categories and infectious events. RESULTS: In a cohort of 33,753 eligible patients, those with higher HbA1c levels had higher rates of diabetic foot infections and skin and soft tissue infections, with patients with HbA1c ≥8.5% having 23% (95% CI, 5%, 45%) and 22% (95% CI, 5%, 42%) higher rates, respectively, compared with HbA1c 5.5 to <6.5%. Patients in the lower HbA1c categories had higher rates of infection-related and all-cause mortality (P-for-trend <0.001). CONCLUSION: This study highlights the need for greater attention to foot evaluation and skin and soft tissue infections among patients on HD with less than optimal diabetes control.

4.
Open Forum Infect Dis ; 6(6): ofz158, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31205970

ABSTRACT

BACKGROUND: Inpatient HIV care often requires specialized laboratory testing with which practitioners may not be familiar. In addition, computerized physician order entry allows for ordering tests without understanding test indications, but it can also provide a venue for education and diagnostic stewardship. METHODS: All charts of HIV-positive patients hospitalized at a tertiary care public safety net hospital in Houston, Texas, between January 1, 2014, and June 30, 2014, were reviewed for a set list of laboratory tests. Appropriateness of test ordering was assessed by 2 providers. Cost estimates for each test were obtained from Medicaid and a national nonprofit health care charge database. RESULTS: A total of 274 HIV-positive patients were admitted 429 times in the 6-month study period. During the study period, 45% of the study laboratory tests ordered were not indicated. A total of 532 hepatitis serologies were ordered, only 52% of which were indicated. Overall, 71 serum qualitative cytomegalovirus (CMV) polymerase chain reactions (PCRs) and eight CMV quantitative PCRs were ordered, with most (85%) qualitative PCRs ordered for nonspecific signs of infection (eg, fever). Other tests ordered without clear indications included Aspergillus IgE (7), serum Epstein-Barr virus (EBV) PCR (5), parvovirus serology (7), and Toxoplasma IgM (18). Overall, the estimated laboratory cost of inappropriate testing over the study period was between $14 000 and $92 000, depending on which cost database was used. CONCLUSIONS: Many tests ordered in HIV-positive inpatients do not have indications, representing a substantial source of health care waste and cost and potentially leading to inappropriate treatment. Opportunities exist to decrease waste through education of trainees and hospitalists and through implementation of diagnostic stewardship via the electronic medical record.

5.
Int J Health Sci (Qassim) ; 11(3): 18-23, 2017.
Article in English | MEDLINE | ID: mdl-28936146

ABSTRACT

OBJECTIVES: The primary objective of this study was to examine the appropriateness of candidemia management at a Veterans Affairs Medical Center as recommended by the 2009 Infectious Diseases Society of America (IDSA) guidelines for treatment of Candida infections. METHODS: A retrospective analysis of 94 adult patients with blood cultures positive for Candida spp. was performed. Patients were stratified by severity of disease into two groups: non-neutropenic, mild-moderate disease (Group 1, n = 54, 56%) and non-neutropenic, moderate-severe disease (Group 2, n = 40, 42%). RESULTS: Adherence to the IDSA recommendations for recommended antifungal drug, dose, and duration of therapy was low in both groups (16.7% in Group 1 and 17.5% in Group 2). Although adherence was not associated with higher clinical resolution of infection (P = 0.111), it was associated with a significantly lower mortality rate (P = 0.001) when compared to variance from the guidelines at 6 weeks. CONCLUSION: Although adherence to published guidelines for treating patients with candidemia was suboptimal at our institution, patients that were managed based on the guidelines had a statistically lower mortality rate.

6.
Case Rep Med ; 2017: 3531823, 2017.
Article in English | MEDLINE | ID: mdl-28951741

ABSTRACT

Herein we describe the case of an elderly diabetic gentleman presenting with a two-week history of dyspnea and nonproductive cough, found to have a large left anterolateral chest wall mass. Further characterization through computed tomography (CT) of the chest revealed a soft tissue mass in the left anterior lower hemithorax found to be hepatocellular carcinoma (HCC). The liver, spleen, and pancreas were unremarkable. Diagnostic labs were unremarkable. The patient had no history of hepatitis, alcohol abuse, or illicit substance use. Pathological examination and immunohistochemical staining of the chest mass biopsy were consistent with metastatic hepatocellular carcinoma (HCC). The patient opted to pursue no further medical intervention and expired two weeks later. To the authors' knowledge, this is one of very few descriptions of isolated hepatocellular carcinoma found in the absence of a primary liver lesion and classical risk factors for hepatocarcinogenesis. This case highlights that HCC may present independently of liver lesions seen on imaging in a patient without clear signs or symptoms of liver. HCC should be considered in cases of isolated tumors with unclear primaries as ectopic carcinogenesis and occult primary malignancy are possibilities.

7.
Transl Res ; 167(1): 88-103, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26303886

ABSTRACT

Immune reconstitution inflammatory syndrome (IRIS) is characterized by improvement in a previously incompetent human immune system manifesting as worsening of clinical symptoms secondary to the ability of the immune system to now mount a vigorous inflammatory response. IRIS was first recognized in the setting of human immunodeficiency virus, and this clinical setting continues to be where it is most frequently encountered. Hallmarks of the pathogenesis of IRIS, independent of the clinical presentation and the underlying pathogen, include excessive activation of the immune system, with increased circulating effector memory T cells, and elevated levels of serum cytokines and inflammatory markers. Patients with undiagnosed opportunistic infections remain at risk for unmasking IRIS at the time of active antiretroviral therapy (ART) initiation. Systematic screening for opportunistic infections before starting ART is a key element to prevent this phenomenon. Appropriate management of IRIS requires prompt recognition of the syndrome and exclusion of alternative diagnoses, particularly underlying infections and drug resistance. Controlled studies supporting the use of pharmacologic interventions in IRIS are scare, and recommendations are based on case series and expert opinions. The only controlled trial published to date, showed reduction in morbidity in patients with paradoxical tuberculosis-related IRIS with the use of oral corticosteroids. There are currently limited data to recommend other anti-inflammatory or immunomodulatory therapies that are discussed in this review, and further research is needed. Ongoing research regarding the immune pathogenesis of IRIS will likely direct future rational therapeutic approaches and clinical trials.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Immune Reconstitution Inflammatory Syndrome/drug therapy , Immunomodulation , Inflammation/drug therapy , Humans , Immune Reconstitution Inflammatory Syndrome/etiology , Risk Factors
9.
PLoS One ; 8(7): e69646, 2013.
Article in English | MEDLINE | ID: mdl-23936064

ABSTRACT

Antibiotic-resistant infections caused by gram-negative bacteria are a major healthcare concern. Repurposing drugs circumvents the time and money limitations associated with developing new antimicrobial agents needed to combat these antibiotic-resistant infections. Here we identified the off-patent antifungal agent, ciclopirox, as a candidate to repurpose for antibiotic use. To test the efficacy of ciclopirox against antibiotic-resistant pathogens, we used a curated collection of Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae clinical isolates that are representative of known antibiotic resistance phenotypes. We found that ciclopirox, at 5-15 µg/ml concentrations, inhibited bacterial growth regardless of the antibiotic resistance status. At these same concentrations, ciclopirox reduced growth of Pseudomonas aeruginosa clinical isolates, but some of these pathogens required higher ciclopirox concentrations to completely block growth. To determine how ciclopirox inhibits bacterial growth, we performed an overexpression screen in E. coli. This screen revealed that galE, which encodes UDP-glucose 4-epimerase, rescued bacterial growth at otherwise restrictive ciclopirox concentrations. We found that ciclopirox does not inhibit epimerization of UDP-galactose by purified E. coli GalE; however, ΔgalU, ΔgalE, ΔrfaI, or ΔrfaB mutant strains all have lower ciclopirox minimum inhibitory concentrations than the parent strain. The galU, galE, rfaI, and rfaB genes all encode enzymes that use UDP-galactose or UDP-glucose for galactose metabolism and lipopolysaccharide (LPS) biosynthesis. Indeed, we found that ciclopirox altered LPS composition of an E. coli clinical isolate. Taken together, our data demonstrate that ciclopirox affects galactose metabolism and LPS biosynthesis, two pathways important for bacterial growth and virulence. The lack of any reported fungal resistance to ciclopirox in over twenty years of use in the clinic, its excellent safety profiles, novel target(s), and efficacy, make ciclopirox a promising potential antimicrobial agent to use against multidrug-resistant problematic gram-negative pathogens.


Subject(s)
Acinetobacter baumannii/drug effects , Anti-Bacterial Agents/pharmacology , Drug Repositioning , Drug Resistance, Bacterial/drug effects , Escherichia coli/drug effects , Klebsiella pneumoniae/drug effects , Pyridones/pharmacology , Biosynthetic Pathways/drug effects , Ciclopirox , Ciprofloxacin/pharmacology , Drug Resistance, Microbial/drug effects , Escherichia coli/growth & development , Escherichia coli/isolation & purification , Escherichia coli Proteins/metabolism , Galactose/metabolism , Humans , Hydrogen Peroxide/pharmacology , Iron/pharmacology , Lipopolysaccharides/biosynthesis , Lipopolysaccharides/chemistry , Microbial Sensitivity Tests , Microbial Viability/drug effects , Mutation/genetics , Phenotype
10.
PLoS One ; 8(6): e65961, 2013.
Article in English | MEDLINE | ID: mdl-23824211

ABSTRACT

Current efforts to understand antibiotic resistance on the whole genome scale tend to focus on known genes even as high throughput sequencing strategies uncover novel mechanisms. To identify genomic variations associated with antibiotic resistance, we employed a modified genome-wide association study; we sequenced genomic DNA from pools of E. coli clinical isolates with similar antibiotic resistance phenotypes using SOLiD technology to uncover single nucleotide polymorphisms (SNPs) unanimously conserved in each pool. The multidrug-resistant pools were genotypically similar to SMS-3-5, a previously sequenced multidrug-resistant isolate from a polluted environment. The similarity was evenly spread across the entire genome and not limited to plasmid or pathogenicity island loci. Among the pools of clinical isolates, genomic variation was concentrated adjacent to previously reported inversion and duplication differences between the SMS-3-5 isolate and the drug-susceptible laboratory strain, DH10B. SNPs that result in non-synonymous changes in gyrA (encoding the well-known S83L allele associated with fluoroquinolone resistance), mutM, ligB, and recG were unanimously conserved in every fluoroquinolone-resistant pool. Alleles of the latter three genes are tightly linked among most sequenced E. coli genomes, and had not been implicated in antibiotic resistance previously. The changes in these genes map to amino acid positions in alpha helices that are involved in DNA binding. Plasmid-encoded complementation of null strains with either allelic variant of mutM or ligB resulted in variable responses to ultraviolet light or hydrogen peroxide treatment as markers of induced DNA damage, indicating their importance in DNA metabolism and revealing a potential mechanism for fluoroquinolone resistance. Our approach uncovered evidence that additional DNA binding enzymes may contribute to fluoroquinolone resistance and further implicate environmental bacteria as a reservoir for antibiotic resistance.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial/genetics , Escherichia coli/drug effects , Fluoroquinolones/pharmacology , Genotype , DNA, Bacterial/genetics , Escherichia coli/genetics , Microbial Sensitivity Tests , Polymorphism, Single Nucleotide
11.
Drugs ; 73(9): 919-34, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23729001

ABSTRACT

Because of the increasing prevalence and changing microbiological spectrum of invasive fungal infections, some form of amphotericin B still provides the most reliable and broad spectrum therapeutic alternative. However, the use of amphotericin B deoxycholate is accompanied by dose-limited toxicities, most importantly, infusion-related reactions and nephrotoxicity. In an attempt to improve the therapeutic index of amphotericin B, three lipid-associated formulations were developed, including amphotericin B lipid complex (ABLC), liposomal amphotericin B (L-AmB), and amphotericin B colloidal dispersion (ABCD). The lipid composition of all three of these preparations differs considerably and contributes to substantially different pharmacokinetic parameters. ABLC is the largest of the lipid preparations. Because of its size, it is taken up rapidly by macrophages and becomes sequestered in tissues of the mononuclear phagocyte system such as the liver and spleen. Consequently, compared with the conventional formulation, it has lower circulating amphotericin B serum concentrations, reflected in a marked increase in volume of distribution and clearance. Lung levels are considerably higher than those achieved with other lipid-associated preparations. The recommended therapeutic dose of ABLC is 5 mg/kg/day. Because of its small size and negative charge, L-AmB avoids substantial recognition and uptake by the mononuclear phagocyte system. Therefore, a single dose of L-AmB results in a much higher peak plasma level (Cmax) than conventional amphotericin B deoxycholate and a much larger area under the concentration-time curve. Tissue concentrations in patients receiving L-AmB tend to be highest in the liver and spleen and much lower in kidneys and lung. Recommended therapeutic dosages are 3-6 mg/kg/day. After intravenous infusion, ABCD complexes remain largely intact and are rapidly removed from the circulation by cells of the macrophage phagocyte system. On a milligram-to-milligram basis, the Cmax achieved is lower than that attained by conventional amphotericin B, although the larger doses of ABCD that are administered produce an absolute level that is similar to amphotericin B. ABCD exhibits dose-limiting, infusion-related toxicities; consequently, the administered dosages should not exceed 3-4 mg/kg/day. The few comparative clinical trials that have been completed with the lipid-associated formulations have not demonstrated important clinical differences among these agents and amphotericin B for efficacy, although there are significant safety benefits of the lipid products. Furthermore, only one published trial has ever compared one lipid product against another for any indication. The results of these trials are particularly difficult to interpret because of major heterogeneities in study design, disease definitions, drug dosages, differences in clinical and microbiological endpoints as well as specific outcomes examined. Nevertheless, it is possible to derive some general conclusions given the available data. The most commonly studied syndrome has been empiric therapy for febrile neutropenic patients, where the lipid-associated preparations did not appear to provide a survival benefit over conventional amphotericin B deoxycholate, but did offer a significant advantage for the prevention of various breakthrough invasive fungal infections. For treatment of documented invasive fungal infections that usually involved hematological malignancy patients, no individual randomized trial has demonstrated a mortality benefit due to therapy with one of the lipid formulations. Results from meta-analyses have been contradictory, with one demonstrating a mortality benefit from all-cause mortality and one that did not demonstrate a mortality benefit. In the only published study to examine HIV-infected patients with disseminated histoplasmosis, clinical success and mortality were significantly better with L-AmB compared with amphotericin B deoxycholate; there were no differences in microbiological outcomes between treatment groups. The lipid-associated preparations were not significantly better than amphotericin B deoxycholate for treatment of AIDS-associated acute cryptococcal meningitis for either clinical or microbiological outcomes that were studied. In all of the trials that specifically examined renal toxicity, the lipid-associated formulations were significantly less nephrotoxic than amphotericin B deoxycholate. Infusion-related reactions occurred less frequently with L-AmB when compared with amphotericin B deoxycholate; however, ABCD had equivalent or more frequent infusion-related reactions than conventional amphotericin B, and this resulted in the cessation of at least one clinical trial. At the present time, this particular lipid formulation is no longer commercially available. For the treatment of most invasive fungal infections, an amphotericin B lipid formulation provides a safer alternative than conventional amphotericin B, with at least equivalent efficacy. As the cost of therapy with these agents continues to decline, these drugs will likely maintain their important role in the antifungal drug armamentarium because of their efficacy and improved safety profile.


Subject(s)
Amphotericin B/chemistry , Amphotericin B/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Fungi/drug effects , Mycoses/drug therapy , Amphotericin B/adverse effects , Animals , Antifungal Agents/adverse effects , Chemistry, Pharmaceutical/methods , Humans , Lipids/chemistry
12.
J Clin Med Res ; 4(6): 415-23, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23226175

ABSTRACT

BACKGROUND: The clinical importance of an elevated platelet count is often overlooked, particularly as a diagnostic clue to the presence of an underlying infection. We sought to better describe the relationship between thrombocytosis and inflammatory conditions, with a focus on infectious causes. METHODS: We retrospectively reviewed 801 sequential cases of thrombocytosis (platelet count > 500 × 10(9)/L) at a tertiary care hospital. RESULTS: Essential thrombocythemia was the most common cause of primary thrombocytosis, and these patients were more likely to have extreme (> 800 × 10(9)/L) and prolonged (> 1 month) thrombocytosis. Secondary thrombocytosis was more common than primary, with infectious causes accounting for nearly half the cases. Demographic factors associated with an infectious etiology included inpatient status, quadriplegia/paraplegia, an indwelling prosthesis, dementia and diabetes. Clinical and laboratory characteristics associated with an infectious cause of thrombocytosis included fever, tachycardia, weight loss, hypoalbuminemia, neutrophilia, leukocytosis and anemia. Patients with thrombocytosis secondary to infection had a more rapid normalization of platelet count, but higher risk of dying, than those with secondary, non-infectious causes. CONCLUSIONS: Infection is a common cause of thrombocytosis and should be considered in patients with comorbidities that increase risk of infection and when clinical and/or laboratory data support an infectious etiology. Thrombocytosis may have prognostic implications as a clinical parameter.

14.
Clin Infect Dis ; 51(2): 225-32, 2010 Jul 15.
Article in English | MEDLINE | ID: mdl-20536366

ABSTRACT

BACKGROUND. It is generally acknowledged that amphotericin B is the most effective treatment for cryptococcal meningitis. However, administration of this drug is accompanied by substantial adverse effects. This double-blind study, performed before the routine availability of highly active antiretroviral therapy, was designed to compare the efficacy and safety of liposomal amphotericin B to conventional amphotericin deoxycholate in patients with acquired immunodeficiency syndrome (AIDS) and acute cryptococcal meningitis. METHODS. Patients were randomized (ratio, 1:1:1) from multiple sites in the United States and Canada to receive either amphotericin B at 0.7 mg/kg/day (n = 87), liposomal amphotericin B at 3 mg/kg/day (n = 86), or liposomal amphotericin B at 6 mg/kg/day (n = 94). RESULTS. Efficacy was similar among all 3 treatment groups. The overall incidence of infusion-related reactions was significantly lower for both the 3 mg/kg/day and 6 mg/kg/day dosages of liposomal amphotericin B, compared with conventional amphotericin B (P < .001). Significantly fewer patients who received the 3 mg/kg/day dosage of liposomal amphotericin B developed nephrotoxicity, indicated by a doubling of the serum creatinine value, compared with recipients of conventional amphotericin B (P = .004). Overall mortality at 10 weeks was 11.6%, with no significant differences among the treatment groups. CONCLUSIONS. Liposomal amphotericin B provides an equally efficacious alternative to conventional amphotericin B deoxycholate in patients with AIDS and acute cryptococcal meningitis. Liposomal amphotericin B at a dosage of 3 mg/kg/day is accompanied by significantly fewer adverse effects.


Subject(s)
AIDS-Related Opportunistic Infections/drug therapy , Amphotericin B/administration & dosage , Antifungal Agents/administration & dosage , Deoxycholic Acid/administration & dosage , Meningitis, Cryptococcal/drug therapy , Adolescent , Adult , Aged , Amphotericin B/adverse effects , Antifungal Agents/adverse effects , Canada , Child , Creatinine/blood , Deoxycholic Acid/adverse effects , Double-Blind Method , Drug Combinations , Female , Humans , Kidney Diseases/chemically induced , Male , Meningitis, Cryptococcal/mortality , Middle Aged , Treatment Outcome , United States , Young Adult
15.
Clin Infect Dis ; 50(3): 291-322, 2010 Feb 01.
Article in English | MEDLINE | ID: mdl-20047480

ABSTRACT

Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. These guidelines for its management have been built on the previous Infectious Diseases Society of America guidelines from 2000 and include new sections. There is a discussion of the management of cryptococcal meningoencephalitis in 3 risk groups: (1) human immunodeficiency virus (HIV)-infected individuals, (2) organ transplant recipients, and (3) non-HIV-infected and nontransplant hosts. There are specific recommendations for other unique risk populations, such as children, pregnant women, persons in resource-limited environments, and those with Cryptococcus gattii infection. Recommendations for management also include other sites of infection, including strategies for pulmonary cryptococcosis. Emphasis has been placed on potential complications in management of cryptococcal infection, including increased intracranial pressure, immune reconstitution inflammatory syndrome (IRIS), drug resistance, and cryptococcomas. Three key management principles have been articulated: (1) induction therapy for meningoencephalitis using fungicidal regimens, such as a polyene and flucytosine, followed by suppressive regimens using fluconazole; (2) importance of early recognition and treatment of increased intracranial pressure and/or IRIS; and (3) the use of lipid formulations of amphotericin B regimens in patients with renal impairment. Cryptococcosis remains a challenging management issue, with little new drug development or recent definitive studies. However, if the diagnosis is made early, if clinicians adhere to the basic principles of these guidelines, and if the underlying disease is controlled, then cryptococcosis can be managed successfully in the vast majority of patients.


Subject(s)
Case Management/standards , Cryptococcosis/diagnosis , Cryptococcosis/therapy , Antifungal Agents/therapeutic use , Child , Child, Preschool , Cryptococcosis/complications , Female , Humans , Intracranial Hypertension/surgery , Pregnancy , United States
16.
Ann Pharmacother ; 43(5): 908-13, 2009 May.
Article in English | MEDLINE | ID: mdl-19401476

ABSTRACT

BACKGROUND: Itraconazole is the preferred drug for chronic maintenance therapy in HIV-infected patients with disseminated histoplasmosis. Unfortunately, few clinical data exist confirming a presumed interaction between itraconazole and nonnucleoside reverse transcriptase inhibitors (NNRTIs). OBJECTIVE: To determine whether serum itraconazole concentrations are affected by the type of antiretroviral therapy (NNRTI or protease inhibitor [PI]) being taken concomitantly. METHODS: This retrospective cohort identified patients on antiretroviral therapy and itraconazole for disseminated histoplasmosis between January 2003 and December 2006 at a large HIV clinic in Houston, TX. Available laboratory values were abstracted from medical records. RESULTS: Thirteen itraconazole concentrations from 10 patients were available for analysis: 7 patients were on concomitant PIs, 4 on concomitant NNRTIs, and 2 on antiretroviral regimens containing both PIs and NNRTIs. Six of the itraconazole concentrations during concomitant PI treatment were therapeutic (>1.0 microg/mL), in contrast with none in patients taking an NNRTI. All patients taking concomitant NNRTIs had undetectable serum itraconazole concentrations (<0.05 microg/mL). Two patients switched from NNRTI-based to PI-based antiretroviral regimens and subsequently reached therapeutic itraconazole concentrations. Although limited by small sample size, this study provides the largest clinical data among HIV-infected patients demonstrating that coadministration of an NNRTI and itraconazole results in significant decreases in itraconazole blood concentrations, likely by inducing the CYP3A4 enzyme system. CONCLUSIONS: Itraconazole concentrations should be monitored in patients taking concomitant NNRTIs. PI-based highly active antiretroviral therapy (HAART) may be preferred over NNRTI-based HAART when itraconazole is used to treat HIV-infected patients with disseminated histoplasmosis.


Subject(s)
Anti-HIV Agents/administration & dosage , HIV Infections/complications , HIV Infections/drug therapy , Histoplasmosis/complications , Histoplasmosis/drug therapy , Itraconazole/administration & dosage , Protease Inhibitors/administration & dosage , Adult , Antiretroviral Therapy, Highly Active , Drug Interactions , Female , HIV Reverse Transcriptase/antagonists & inhibitors , Humans , Itraconazole/blood , Male , Middle Aged , Retrospective Studies , Time Factors
17.
Antimicrob Agents Chemother ; 53(1): 229-34, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18838594

ABSTRACT

Fluoroquinolones are some of the most prescribed antibiotics in the United States. Previously, we and others showed that the fluoroquinolones exhibit a class effect with regard to the CLSI-established breakpoints for resistance, such that decreased susceptibility (i.e., an increased MIC) to one fluoroquinolone means a simultaneously decreased susceptibility to all. For defined strains, however, clear differences exist in the pharmacodynamic properties of each fluoroquinolone and the extent to which resistance-associated genotypes affect the MICs of each fluoroquinolone. In a pilot study of 920 clinical Escherichia coli isolates, we uncovered tremendous variation in norfloxacin MICs. The MICs for all of the fluoroquinolone-resistant isolates exceeded the resistance breakpoint, reaching 1,000 microg/ml. Approximately 25% of the isolates (n = 214), representing the full range of resistant norfloxacin MICs, were selected for the simultaneous determinations of ciprofloxacin, gatifloxacin, levofloxacin, and norfloxacin MICs. We found that (i) great MIC variation existed for all four fluoroquinolones, (ii) the ciprofloxacin and levofloxacin MICs of >90% of the fluoroquinolone-resistant isolates were higher than the resistance breakpoints, (iii) ciprofloxacin and levofloxacin MICs were distributed into two distinct groups, (iv) the MICs of two drug pairs (ciprofloxacin and norfloxacin by Kendall's Tau-b test and gatifloxacin and levofloxacin by paired t test) were similar with statistical significance but were different from each other, and (v) approximately 2% of isolates had unprecedented fluoroquinolone MIC relationships. Thus, although the fluoroquinolones can be considered equivalent with regard to clinical susceptibility or resistance, fluoroquinolone MICs differ dramatically for fluoroquinolone-resistant clinical isolates, likely because of differences in drug structure.


Subject(s)
Ciprofloxacin/pharmacology , Escherichia coli/drug effects , Fluoroquinolones/pharmacology , Levofloxacin , Norfloxacin/pharmacology , Ofloxacin/pharmacology , Drug Resistance, Bacterial , Escherichia coli/isolation & purification , Gatifloxacin , Microbial Sensitivity Tests , United States
19.
BMC Infect Dis ; 8: 4, 2008 Jan 15.
Article in English | MEDLINE | ID: mdl-18197977

ABSTRACT

BACKGROUND: Escherichia coli infections are common and often treated with fluoroquinolones. Fluoroquinolone resistance is of worldwide importance and is monitored by national and international surveillance networks. In this study, we analyzed the effects of time, culture site, and patient age, sex, and location on fluoroquinolone resistance in E. coli clinical isolates. METHODS: To understand how patient factors and time influenced fluoroquinolone resistance and to determine how well data from surveillance networks predict trends at Ben Taub General Hospital in Houston, TX, we used Perl to parse and MySQL to house data from antibiograms (n congruent with 21,000) for E. coli isolated between 1999 to 2004 using Chi Square, Bonferroni, and Multiple Linear Regression methods. RESULTS: Fluoroquinolone resistance (i) increased with time; (ii) exceeded national averages by 2- to 4-fold; (iii) was higher in males than females, largely because of urinary isolates from male outpatients; (iv) increased with patient age; (v) was 3% in pediatric patients; (vi) was higher in hospitalized patients than outpatients; (vii) was higher in sputum samples, particularly from inpatients, than all other culture sites, including blood and urine, regardless of patient location; and (viii) was lowest in genital isolates than all other culture sites. Additionally, the data suggest that, with regard to susceptibility or resistance by the Dade Behring MicroScan system, a single fluoroquinolone suffices as a "surrogate marker" for all of the fluoroquinolone tested. CONCLUSION: Large surveillance programs often did not predict E. coli fluoroquinolone resistance trends at a large, urban hospital with a largely indigent, ethnically diverse patient population or its affiliated community clinics.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial/drug effects , Escherichia coli Infections/drug therapy , Escherichia coli/drug effects , Fluoroquinolones/pharmacology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Child, Preschool , Escherichia coli Infections/epidemiology , Female , Hospitals, County , Humans , Infant , Infant, Newborn , Male , Middle Aged , Sentinel Surveillance , Sex Factors , Texas/epidemiology
20.
Med Mycol ; 45(6): 513-8, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17710620

ABSTRACT

A pilot candidate gene association study was conducted to investigate the role of three common functional genetic polymorphisms of the low-affinity Fc gamma receptors, FCGR2A (131H/R), FCGR3A (158F/V) and FCGR3B (NA1/NA2) in Cryptococcus neoformans infections in individuals not infected with HIV. The FCGR2A 131RR and FCGR3A 158VV genotypes were over-represented [OR: 1.67 (1.05-2.63) and 2.04 (1.06-4.00), respectively] whereas the FCGR3B NA2NA2 was under-represented in patients with cryptococcosis (28% vs. 40% in controls). An analysis of haplotypes showed a significant difference in distribution between cases and controls overall and in Caucasians.


Subject(s)
Antigens, CD/genetics , Cryptococcosis/genetics , HIV Seronegativity , Polymorphism, Genetic , Receptors, IgG/genetics , Case-Control Studies , Cryptococcosis/epidemiology , Cryptococcus neoformans , Female , GPI-Linked Proteins , Genetic Predisposition to Disease , Genotype , Haplotypes , Humans , Male , Middle Aged , Pilot Projects , Risk Factors , White People
SELECTION OF CITATIONS
SEARCH DETAIL
...