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1.
Transfusion ; 61(2): 641-648, 2021 02.
Article in English | MEDLINE | ID: mdl-33616945

ABSTRACT

BACKGROUND: Pathogen reduction technology and enhanced bacterial culture screening promise to significantly reduce the risk of transfusion-associated septic reactions due to contaminated platelets. Recent reports suggest that these interventions lack efficacy for post-collection and processing contamination with environmental organisms if the storage bag integrity is compromised. CASE REPORT: We report a fatal septic transfusion reaction in a 63-year-old patient with chronic kidney and liver disease who received a pathogen reduced platelet transfusion in anticipation of surgery. METHODS: The residual platelet concentrate was cultured, with the detected microorganisms undergoing 16S genotype sequencing. Separate pathogen reduction studies were performed on the recovered bacteria, including assessment for amotosalen photoproducts. The storage container was subjected to pressure testing and microscopic examination. Environmental culture screening was performed at the hospital. RESULTS: Gram negative rods were detected in the platelet unit and cultures of both platelet component and the patient's blood grew Acinetobacter baumannii complex, Leclercia adecarboxylata and Staphylococcus saprophyticus. These strains were effectively inactivated with >7.2, 7.7, and >7.1 log10 kill, respectively. The platelet storage container revealed a leak visible only on pressure testing. Hospital environmental cultures were negative and the contamination source is unknown. A. baumannii complex and S. saprophyticus 16S genotyping sequences were identical to those implicated in a previously reported septic reaction. CONCLUSION: Findings are compatible with post-processing environmental contamination of a pathogen reduced platelet concentrate via a non-visible, acquired storage container leak. Efforts are warranted to actively prevent damage to, and detect defects in, platelet storage containers, and to store and transport components in clean environments.


Subject(s)
Acinetobacter Infections/etiology , Coinfection/etiology , Cross Infection/etiology , Enterobacteriaceae Infections/etiology , Equipment Contamination , Equipment Failure , Platelet Transfusion/adverse effects , Platelet Transfusion/instrumentation , Sepsis/etiology , Staphylococcal Infections/etiology , Transfusion Reaction/etiology , Acinetobacter Infections/microbiology , Acinetobacter baumannii/isolation & purification , Blood Platelets/microbiology , Blood-Borne Pathogens/drug effects , Blood-Borne Pathogens/radiation effects , Coinfection/microbiology , Cross Infection/microbiology , Enterobacteriaceae/isolation & purification , Enterobacteriaceae Infections/microbiology , Fatal Outcome , Furocoumarins , Hip Fractures/complications , Humans , Male , Middle Aged , Sepsis/microbiology , Staphylococcal Infections/microbiology , Staphylococcus saprophyticus/isolation & purification , Thrombocytopenia/complications , Thrombocytopenia/therapy , Transfusion Reaction/microbiology , Ultraviolet Rays
2.
J Infect Chemother ; 25(6): 413-422, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30905628

ABSTRACT

The Japanese Surveillance Committee conducted a second nationwide surveillance of antimicrobial susceptibility patterns of uropathogens responsible for acute uncomplicated cystitis (AUC) in premenopausal patients aged 16-40 years old at 31 hospitals throughout Japan from March 2015 to February 2016. In this study, the susceptibility of causative bacteria (Escherichia coli, Klebsiella pneumoniae, Staphylococcus saprophyticus) for various antimicrobial agents was investigated by isolation and culturing of organisms obtained from urine samples. In total, 324 strains were isolated from 361 patients, including E. coli (n = 220, 67.9%), S. saprophyticus (n = 36, 11.1%), and K. pneumoniae (n = 7, 2.2%). The minimum inhibitory concentrations (MICs) of 20 antibacterial agents for these strains were determined according to the Clinical and Laboratory Standards Institute (CLSI) manual. At least 93% of the E. coli isolates showed susceptibility to fluoroquinolones and cephalosporins, whereas 100% of the S. saprophyticus isolates showed susceptibility to fluoroquinolones and aminoglycosides. The proportions of fluoroquinolone-resistant and extended-spectrum ß-lactamase (ESBL)-producing E. coli strains were 6.4% (13/220) and 4.1% (9/220), respectively. The antimicrobial susceptibility of K. pneumoniae was retained during the surveillance period, while no multidrug-resistant strains were identified. In summary, antimicrobial susceptibility results of our second nationwide surveillance did not differ significantly from those of the first surveillance. Especially the numbers of fluoroquinolone-resistant and ESBL-producing E. coli strains were not increased in premenopausal patients with AUC in Japan.


Subject(s)
Anti-Bacterial Agents/pharmacology , Cystitis/drug therapy , Drug Resistance, Multiple, Bacterial , Escherichia coli/drug effects , Klebsiella pneumoniae/drug effects , Staphylococcus saprophyticus/drug effects , Adolescent , Adult , Anti-Bacterial Agents/therapeutic use , Cystitis/epidemiology , Cystitis/microbiology , Epidemiological Monitoring , Escherichia coli/isolation & purification , Escherichia coli/metabolism , Female , Humans , Japan , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/metabolism , Male , Microbial Sensitivity Tests , Middle Aged , Staphylococcus saprophyticus/isolation & purification , Staphylococcus saprophyticus/metabolism , Young Adult , beta-Lactamases/metabolism
3.
Microb Pathog ; 119: 9-11, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29604423

ABSTRACT

Staphylococcus saprophyticus is an important pathogen responsible for community urinary tract infections (UTI). Besides composing the human microbiota, this species is widely distributed in the environment and the origins of this organism for human infection is not fully characterized. Although some virulence determinants are known, such as d-serine deaminase (DsdA), urease and cell-wall associated proteins, few studies investigated the distribution of virulence-associated genes and analyzed the pathogenic potential of S. saprophyticus strains from different sources. The aim of the present study was to detect the presence of S. saprophyticus genes encoding surface proteins UafA, Aas, Ssp, SdrI, SssF as well as the DsdA and urease enzymes. A total of 142 S. saprophyticus strains were obtained from four sources: UTI, colonization, water and food. It was found, in every tested strain, the presence of genes encoding the surface proteins UafA, Aas, Ssp and SssF and the DsdA and urease enzymes. In contrast, the gene encoding SdrI surface protein was not detected in any of the strains of S. saprophyticus. These results provide a better understanding of the characteristics of S. saprophyticus strains and suggest that isolates from non-human sources have a potential to colonize the urinary tract.


Subject(s)
Bacterial Proteins/genetics , Genes, Bacterial/genetics , Staphylococcal Infections/microbiology , Staphylococcus saprophyticus/genetics , Staphylococcus saprophyticus/isolation & purification , Virulence Factors/genetics , Brazil , DNA, Bacterial/isolation & purification , Female , Humans , Hydro-Lyases/genetics , Membrane Proteins/genetics , Staphylococcus saprophyticus/enzymology , Staphylococcus saprophyticus/pathogenicity , Urease/genetics , Urinary Tract/microbiology , Urinary Tract Infections/microbiology , Virulence/genetics
4.
Int J Mol Sci ; 19(7)2018 Jun 21.
Article in English | MEDLINE | ID: mdl-29933576

ABSTRACT

Culture-independent studies have identified DNA of bacterial pathogens in the gallbladder under pathological conditions, yet reports on the isolation of corresponding live bacteria are rare. Thus, it is unclear which pathogens, or pathogen communities, can colonize the gallbladder and cause disease. Using light microscopy, scanning electron microscopy, culture techniques, phylogenetic analysis, urease assays and Western blotting, we investigated the presence of live bacterial communities in the gallbladder of a cholecystitis patient after cholecystectomy. 16S rRNA gene sequencing of isolated bacterial colonies revealed the presence of pathogens most closely resembling Corynebacterium urinapleomorphum nov. sp., Staphylococcus saprophyticus and Helicobacter pylori. The latter colonies were confirmed as H. pylori by immunohistochemistry and biochemical methods. H. pylori cultured from the gallbladder exhibited both the same DNA fingerprinting and Western cagA gene sequence with ABC-type EPIYA (Glu-Pro-Ile-Tyr-Ala) phosphorylation motifs as isolates recovered from the gastric mucus of the same patient, suggesting that gastric H. pylori can also colonize other organs in the human body. Taken together, here we report, for the first time, the identification and characterization of a community consisting of live S. saprophyticus; C. urinapleomorphum, and H. pylori in the gallbladder of a patient with acute cholecystitis. Their potential infection routes and roles in pathogenesis are discussed.


Subject(s)
Bacterial Infections/microbiology , Cholecystitis, Acute/microbiology , Corynebacterium/pathogenicity , Gallbladder/microbiology , Helicobacter pylori/pathogenicity , Staphylococcus saprophyticus/pathogenicity , Antigens, Bacterial/genetics , Bacterial Infections/pathology , Bacterial Infections/surgery , Bacterial Proteins/genetics , Bacterial Typing Techniques , Cholecystitis, Acute/pathology , Cholecystitis, Acute/surgery , Corynebacterium/classification , Corynebacterium/genetics , Corynebacterium/isolation & purification , Gallbladder/pathology , Gallbladder/surgery , Gene Expression , Helicobacter pylori/classification , Helicobacter pylori/genetics , Helicobacter pylori/isolation & purification , Humans , Male , Middle Aged , Phylogeny , RNA, Ribosomal, 16S/genetics , Staphylococcus saprophyticus/classification , Staphylococcus saprophyticus/genetics , Staphylococcus saprophyticus/isolation & purification , Stomach/microbiology , Stomach/pathology
5.
World J Microbiol Biotechnol ; 34(12): 174, 2018 Nov 16.
Article in English | MEDLINE | ID: mdl-30446832

ABSTRACT

Cementation of salt-containing soils can be achieved by salt-tolerant or halophilic calcite precipitation bacteria. Therefore, the isolation of calcite-producing bacteria in the presence of salt is the first step in the microbial cementation of saline soils. Urease producing bacteria can cause calcite nano-crystals to precipitate by producing urease in the presence of urea and calcium. The purpose of this study was to isolate urease producing halophilic bacteria in order to make calcite precipitate in saline soil. The calcite and the properties of the strains were further analyzed by X-ray diffraction (XRD) and scanning electron microscope equipped with an energy dispersive X-ray detector. In this study, a total of 110 halophilic strains were isolated, from which 58 isolates proved to have the ability of urease production. Four strains were identified to produce nano-calcite using urease activity in the precipitation medium. The XRD studies showed that the size of these particles was in the range of 40-60 nm. Strain H3 revealed that calcite is mostly produced in the precipitation medium containing 5% salt in comparison with other strains. This strain also produced calcite precipitates in the precipitation medium containing 15% salt. Phylogenetic analysis indicated that these isolates are about 99-100% similar to Staphylococcus saprophyticus.


Subject(s)
Calcium Carbonate/metabolism , Microscopy, Electron, Scanning/methods , Nanoparticles/metabolism , Staphylococcus saprophyticus/enzymology , Urease/metabolism , X-Ray Diffraction/methods , Calcium Carbonate/chemistry , Calcium Carbonate/isolation & purification , Environmental Microbiology , Iran , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Particle Size , Phylogeny , RNA, Ribosomal, 16S/genetics , Staphylococcus saprophyticus/classification , Staphylococcus saprophyticus/isolation & purification , Staphylococcus saprophyticus/metabolism , Urea/metabolism , Urease/isolation & purification
6.
J Antimicrob Chemother ; 72(2): 529-534, 2017 02.
Article in English | MEDLINE | ID: mdl-27733519

ABSTRACT

BACKGROUND: Fluoroquinolone-non-susceptible Escherichia coli isolated from patients with acute uncomplicated cystitis are a matter of increasing concern. Cefditoren pivoxil is an oral, ß-lactamase-stable, extended-spectrum cephalosporin that is effective against fluoroquinolone-non-susceptible bacteria. OBJECTIVES: To evaluate the clinical and microbiological efficacies of cefditoren pivoxil against acute uncomplicated cystitis and to determine the optimal duration of cefditoren pivoxil treatment. METHODS: We compared 3 and 7 day regimens of cefditoren pivoxil in a multicentre, randomized, open-label study. RESULTS: A total of 104 female patients with acute uncomplicated cystitis were enrolled and randomized into 3 day (n = 51) or 7 day (n = 53) treatment groups. At first visit, 94 bacterial strains were isolated from the 104 participants of which 81.7% (85/104) were E. coli. Clinical and microbiological efficacies were evaluated 5-9 days following administration of the final dose of cefditoren pivoxil. The clinical efficacies of the 3 and 7 day groups were 90.9% (40/44) and 93.2% (41/44), respectively (P = 1.000). The microbiological efficacies of the 3 and 7 day groups were 82.5% (33/40) and 90.2% (37/41), respectively (P = 0.349). There were no adverse events due to cefditoren pivoxil treatment, with the exception of a mild allergic reaction in one patient, after which the cefditoren pivoxil was exchanged for another antimicrobial. CONCLUSIONS: Cefditoren pivoxil is safe and effective for uncomplicated cystitis, with no significant differences in clinical and microbiological efficacies between 3 and 7 day regimens.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/therapeutic use , Cephalosporins/administration & dosage , Cephalosporins/therapeutic use , Cystitis/drug therapy , Cystitis/microbiology , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/adverse effects , Cephalosporins/adverse effects , Citrobacter koseri/drug effects , Citrobacter koseri/isolation & purification , Drug Resistance, Bacterial , Enterococcus faecalis/drug effects , Enterococcus faecalis/isolation & purification , Escherichia coli/drug effects , Escherichia coli/isolation & purification , Escherichia coli Infections/drug therapy , Escherichia coli Infections/microbiology , Female , Fluoroquinolones/pharmacology , Humans , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/isolation & purification , Microbial Sensitivity Tests , Middle Aged , Staphylococcus saprophyticus/drug effects , Staphylococcus saprophyticus/isolation & purification , Young Adult
7.
J Appl Microbiol ; 122(5): 1380-1388, 2017 May.
Article in English | MEDLINE | ID: mdl-28245081

ABSTRACT

AIMS: Urease is a key virulence factor for the Gram-positive urinary tract pathogen Staphylococcus saprophyticus and a potential target for antimicrobial therapy. The enzyme from S. saprophyticus is unusual in that it does not contain cysteine at the active site. The aims of this study were to test 14 over-the-counter plant preparations as inhibitors of this urease and to determine whether they can prevent the increase in pH that normally occurs in bacterial cultures containing urea. METHODS AND RESULTS: Urease activity was measured colorimetrically by the formation of ammonium ions. The green tea and Uva-Ursi preparations reduced urease activity in a soluble extract of S. saprophyticus by more than 75%. Two herbal mixtures were weakly inhibitory and reduced activity by about 25%, but the other products had little or no effect. The green tea and Uva-Ursi extracts also inhibited urease activity in whole cells by more than 75%. One of the herbal products (WishGarden UTI) showed some inhibition of urease activity but the other (UTI Clear) did not. The green tea and Uva-Ursi preparations prevented the increase in pH that normally occurs when S. saprophyticus is grown in an artificial urine medium, but this was due primarily to bacterial death. The WishGarden UTI preparation could partially delay the pH increase while allowing some cells to remain viable. CONCLUSION: These results indicate that only a few of the commercially available over-the-counter plant preparations commonly used for the treatment of urinary tract infections (UTIs) can inhibit the urease activity from S. saprophyticus. SIGNIFICANCE AND IMPACT OF THE STUDY: While over-the-counter plant preparations may be considered an alternative to traditional antibiotics for the treatment of UTIs, they should be used with caution and a product should be matched to the properties of the virulence factors of the bacterial pathogen involved.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/antagonists & inhibitors , Plant Preparations/pharmacology , Plants/chemistry , Staphylococcus saprophyticus/enzymology , Staphylococcus saprophyticus/isolation & purification , Urease/antagonists & inhibitors , Urinary Tract Infections/microbiology , Anti-Bacterial Agents/chemistry , Bacterial Proteins/metabolism , Humans , Kinetics , Plant Preparations/chemistry , Staphylococcus/drug effects , Staphylococcus saprophyticus/drug effects , Staphylococcus saprophyticus/genetics , Urease/metabolism , Urinary Tract Infections/drug therapy , Virulence Factors/antagonists & inhibitors , Virulence Factors/metabolism
8.
Nihon Hinyokika Gakkai Zasshi ; 108(1): 24-29, 2017.
Article in Japanese | MEDLINE | ID: mdl-29367505

ABSTRACT

(Objectives) We report the clinical features about polymicrobial bacteria detection cases in the uncomplicated urinary tract infection of the premenopausal woman from the voided midstream urine culture. (Methods) We retrospectively reviewed the premenopausal woman from 18-49 years patients visited Sendai City Hospital from April, 2006 to December, 2014, diagnosed uncomplicated cystitis or uncomplicated pyelonephritis. We analyzed for 375 specimens from the voided midstream urine culture. (Results) Among 375 specimens, the urine culture-positive for uropathogens were 211 specimens. The monomicrobial bacterial were detected in 184 specimens (87.2%) and polymicrobial bacterial specimens were 27 specimens (12.8%). The most combination group was the caused bacteria and periurethral microorganisms in 20 specimens (74.1%). Then 6 periurethral microorganisms specimens (22.2%), the caused bacteria were only 1 specimen was overlapped (3.7%). The case of urinary tract infections recurrence or revealed voiding dysfunction that need periodic treatment were more prevalent in the polymicrobial than the monomicrobial group (22.2% vs 9.8%, p=0.043). (Conclusions) When polymicrobial bacteria were detected in uncomplicated urinary tract infection in premenopausal woman, it was confirmed that there were the most combinations of caused bacteria and periurethral microorganisms. In these cases, treatment intended for only the caused bacteria. A risk of the infection recurrence and voiding dysfunction were statistically significant higher rate in the polymicrobial bacteria detection cases, and it might be necessary to consider that search to complicated urinary tract infection.


Subject(s)
Bacteriuria/microbiology , Escherichia coli/isolation & purification , Klebsiella pneumoniae/isolation & purification , Premenopause , Proteus mirabilis/isolation & purification , Urinary Tract Infections/microbiology , Adolescent , Adult , Corynebacterium/isolation & purification , Female , Humans , Middle Aged , Staphylococcus/isolation & purification , Staphylococcus saprophyticus/isolation & purification , Urinary Tract Infections/complications , Urination Disorders/etiology , Urination Disorders/microbiology , Young Adult
9.
J Clin Microbiol ; 54(12): 2905-2909, 2016 12.
Article in English | MEDLINE | ID: mdl-27629897

ABSTRACT

Disk diffusion testing is widely used to detect methicillin resistance in staphylococci, and cefoxitin is currently considered the best marker for mecA-mediated methicillin resistance. In low-inoculum diffusion testing (colony suspension at 106 CFU/ml), the addition of moxalactam in combination with cefoxitin has been reported to improve on cefoxitin alone for the detection of methicillin-heteroresistant staphylococci. However, moxalactam is absent from EUCAST and CLSI guidelines, which use high-inoculum diffusion testing (colony suspension at 108 CFU/ml), calling into question the potential interest of including moxalactam in their recommendations. The inhibition zone diameters of cefoxitin and moxalactam, alone and in combination, were evaluated for concordance with mecA and mecC positivity in a large collection of clinical Staphylococcus isolates (611 Staphylococcus aureus, Staphylococcus lugdunensis, and Staphylococcus saprophyticus isolates and 307 coagulase-negative staphylococci other than S. lugdunensis and S. saprophyticus isolates, of which 22% and 53% were mecA-positive, respectively) and in 25 mecC-positive S. aureus isolates using high-inoculum diffusion testing. Receiver operating characteristic, sensitivity, and specificity analyses indicated that the detection of mecA- and mecC-positive and negative isolates did not improve with moxalactam, either alone or in combination with cefoxitin, compared to cefoxitin alone. These findings were similar in both the S. aureus/S. lugdunensis/S. saprophyticus group and in the coagulase-negative staphylococci group. Our results do not support the use of moxalactam as an additional marker of methicillin resistance when testing with high-inoculum disk diffusion.


Subject(s)
Anti-Bacterial Agents/pharmacology , Cefoxitin/pharmacology , Disk Diffusion Antimicrobial Tests/methods , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Moxalactam/pharmacology , Bacterial Proteins/genetics , Humans , Methicillin-Resistant Staphylococcus aureus/genetics , Penicillin-Binding Proteins/genetics , Staphylococcus lugdunensis/drug effects , Staphylococcus lugdunensis/genetics , Staphylococcus lugdunensis/isolation & purification , Staphylococcus saprophyticus/drug effects , Staphylococcus saprophyticus/genetics , Staphylococcus saprophyticus/isolation & purification
10.
J Clin Microbiol ; 53(9): 2805-9, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26063858

ABSTRACT

Urinary tract infections (UTIs) are frequently encountered in clinical practice and most commonly caused by Escherichia coli and other Gram-negative uropathogens. We tested RapidBac, a rapid immunoassay for bacteriuria developed by Silver Lake Research Corporation (SLRC), compared with standard bacterial culture using 966 clean-catch urine specimens submitted to a clinical microbiology laboratory in an urban academic medical center. RapidBac was performed in accordance with instructions, providing a positive or negative result in 20 min. RapidBac identified as positive 245/285 (sensitivity 86%) samples with significant bacteriuria, defined as the presence of a Gram-negative uropathogen or Staphylococcus saprophyticus at ≥10(3) CFU/ml. The sensitivities for Gram-negative bacteriuria at ≥10(4) CFU/ml and ≥10(5) CFU/ml were 96% and 99%, respectively. The specificity of the test, detecting the absence of significant bacteriuria, was 94%. The sensitivity and specificity of RapidBac were similar on samples from inpatient and outpatient settings, from male and female patients, and across age groups from 18 to 89 years old, although specificity was higher in men (100%) compared with that in women (92%). The RapidBac test for bacteriuria may be effective as an aid in the point-of-care diagnosis of UTIs especially in emergency and primary care settings.


Subject(s)
Bacteriuria/diagnosis , Diagnostic Tests, Routine/methods , Immunoassay/methods , Point-of-Care Systems , Adolescent , Adult , Aged , Aged, 80 and over , Escherichia coli/isolation & purification , Female , Humans , Male , Middle Aged , Sensitivity and Specificity , Staphylococcus saprophyticus/isolation & purification , Time Factors , Young Adult
11.
J Antimicrob Chemother ; 70(4): 1076-82, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25515669

ABSTRACT

OBJECTIVES: To determine the pharmacokinetic/pharmacodynamic index that best correlates to nitrofurantoin's antibacterial effect, we studied nitrofurantoin activity against common causative pathogens in uncomplicated urinary tract infection (UTI). METHODS: Five isolates [two Escherichia coli (one isolate producing the ESBL CTX-M-15), two Enterococcus faecium (including one that was vancomycin resistant) and one Staphylococcus saprophyticus] were used. The MICs of nitrofurantoin were determined by Etest. Time-kill curves with different concentrations of nitrofurantoin (based on multiples of isolate-specific MICs) were followed over 24 h. An in vitro kinetic model was used to simulate different time-concentration profiles, exposing E. coli to nitrofurantoin for varying proportions of the dosing interval. The outcome parameters reduction in cfu 0-24 h (Δcfu0-24) and the area under the bactericidal curve (AUBC), were correlated with time over MIC (T>MIC) and area under the antibiotic concentration curve divided by the MIC (AUC/MIC). RESULTS: A bactericidal effect at varying static drug concentrations was achieved for all isolates. All isolates showed similar kill curve profiles. In the kinetic model, the effect of nitrofurantoin on E. coli displayed a 4 log reduction in cfu/mL within 6 h at 8 × MIC. The outcome parameters Δcfu0-24 and AUBC had a good correlation with T>MIC (R ≈ 0.83 and R ≈ 0.67, respectively), whereas log(AUC/MIC) was significantly poorer (R ≈ 0.39 and R ≈ 0.53, respectively). CONCLUSIONS: Nitrofurantoin was highly effective against E. coli and S. saprophyticus isolates; the killing effect against E. faecium was not as rapid, but still significant. Against E. coli, nitrofurantoin was mainly associated with a concentration-dependent action; this was confirmed in the kinetic model, in which T>MIC displayed the best correlation.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Infections/microbiology , Enterococcus faecium/drug effects , Escherichia coli/drug effects , Nitrofurantoin/pharmacology , Staphylococcus saprophyticus/drug effects , Urinary Tract Infections/microbiology , Anti-Bacterial Agents/pharmacokinetics , Enterococcus faecium/isolation & purification , Escherichia coli/isolation & purification , Humans , Microbial Sensitivity Tests , Microbial Viability/drug effects , Models, Theoretical , Nitrofurantoin/pharmacokinetics , Staphylococcus saprophyticus/isolation & purification
12.
J Infect Chemother ; 21(9): 695-9, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26184852

ABSTRACT

A 61-year-old man was admitted to our hospital with 2-day history of malaise and dyspnea. He had mitral prolapse and type II diabetes mellitus with neurogenic bladder, which was cared for by catheterization on his own. On arrival the patient was in septic condition with hypoxemia, and physical examination revealed systolic murmur at the apex. Transthoracic echocardiography revealed vegetation of the mitral and the aortic valve. The presence of continuous bacteremia was confirmed by multiple sets of blood culture, whereby gram-positive cocci was retrieved and identified as Staphylococcus saprophyticus (S. saprophyticus) both phenotypically and genetically. Because two major criteria of the Modified Duke Criteria were met, the patient was diagnosed with native valve endocarditis due to S. saprophyticus. The urine culture was also positive for gram-positive cocci, phenotypically identified as Staphylococcus warneri, which was subsequently identified as S. saprophyticus with the use of 16S rRNA gene sequence analysis and MALDI-TOF MS (matrix-assisted laser desorption ionization time of flight mass spectrometry), indicating strongly that the intermittent catheterization-associated urinary tract infection resulted in bacteremia that eventually lead to infective endocarditis. This patient was treated with vancomycin and clindamycin. Because of multiple cerebral infarctions, the patient underwent mitral and aortic valve replacement on hospital day 5. Blood culture turned negative at 6th hospital day. Antibiotic therapy was continued for six weeks after surgery. The patient's clinical course was uneventful thereafter, and was discharged home. This is the first case report of native valve endocarditis caused by S. saprophyticus of confirmed urinary origin.


Subject(s)
Aortic Valve , Endocarditis, Bacterial/microbiology , Heart Valve Diseases/microbiology , Mitral Valve , Staphylococcal Infections/complications , Staphylococcus saprophyticus/isolation & purification , Urinary Tract Infections/complications , Bacteremia/microbiology , Diabetes Mellitus, Type 2/complications , Humans , Intermittent Urethral Catheterization/adverse effects , Male , Middle Aged , Urinary Bladder, Neurogenic/complications , Urinary Bladder, Neurogenic/therapy
13.
J Pak Med Assoc ; 65(3): 283-6, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25933562

ABSTRACT

OBJECTIVE: To determine the frequency of isolation of coagulase-negative staphylococci and their resistance to methicillin over a period of time. METHODS: The descriptive cross-sectional study was carried out at Army Medical College, Rawalpindi, from June 2009 to May 2012, and comprised clinical samples mostly from patients admitted to the intensive care unit. They were inoculated onto appropriate culture media depending upon the specimen. After 24-hour incubation at 35°C, coagulase-negative staphylococci were identified on the basis of colony morphology, gram staining, a positive catalase and a negative tube coagulase test.Methicillin resistance among the isolated staphylococci was determined using a 30µg Cefoxitin disc as per the Clinical and Laboratory Standards Institute protocol. Number of coagulase-negative staphylococci for each year and their methicillin resistance rates were calculated. A comparison was made with methicillin resistant staphylococcus aureus) isolated during the same period. RESULTS: Of the total 1331 specimens studies over three years, 581(43.65%) were coagulase-negative staphylococci. The rate of coagulase-negative staphylococci and methicillin resistance was higher each year; 110(26.6%) in May 2009-Jun 2010, 134(36.5%) in 2011, and 337(61%) in 2012. Methicillin resistance rates also increased from 25(22.7%) to 46(34.3%) and then to 201(59.6%) in 2012.Maximum isolated specimens came from blood 311(53.5%), followed by pus/swabs 204(35.1%). CONCLUSIONS: The frequency of isolation of coagulase-negative staphylococci and its methicillin resistance among hospitalised patients is on the rise.


Subject(s)
Bacteremia/microbiology , Bacteriuria/microbiology , Methicillin Resistance/physiology , Staphylococcal Infections/microbiology , Staphylococcus haemolyticus/physiology , Staphylococcus lugdunensis/physiology , Staphylococcus saprophyticus/physiology , Bacteremia/epidemiology , Bacteriuria/epidemiology , Cross-Sectional Studies , Hospitals, Military , Humans , Intensive Care Units , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/physiology , Microbial Sensitivity Tests , Pakistan/epidemiology , Staphylococcal Infections/epidemiology , Staphylococcus/isolation & purification , Staphylococcus/physiology , Staphylococcus haemolyticus/isolation & purification , Staphylococcus lugdunensis/isolation & purification , Staphylococcus saprophyticus/isolation & purification , Suppuration/epidemiology , Suppuration/microbiology , Tertiary Care Centers
14.
Curr Microbiol ; 68(2): 220-6, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24114413

ABSTRACT

Uropathogenic Escherichia coli (UPEC) and Staphylococcus saprophyticus (S. saprophyticus) are responsible for the majority of community-acquired urinary tract infections (UTI). Agar plating, a gold standard for detection of bacterial uropathogens, is labor intensive, limited for distinguishing between environmental contaminants and pathogens, and fails to effectively detect mixed infections. A reliable method for specific and sensitive quantitative assessment of infections would allow cost-effective evaluation of large numbers of experimental samples. A methodology such as quantitative PCR (qPCR) addresses the limitations of agar plating. We developed and validated highly specific and sensitive qPCR assays to assist researchers in the evaluation of potential vaccines and interventions in preclinical models of UPEC and S. saprophyticus UTI. The developed UPEC PCR targeted a highly conserved region of the UPEC hemolysin D (hlyD) gene that reproducibly detected type strains CFT073 and J96 over a 9 log range with high precision. To quantify S. saprophyticus genomes, a separate qPCR assay targeting the Trk transport gene was developed with an 8 log range. Neither assay detected bacterial species predicted to be sample contaminants. Using our optimized workflow that includes automated steps, up to 200 urine or tissue samples can be processed in as few as 3 h. Additionally, sequence comparisons of our primers and probe to other UTI bacterial strains indicated the broad applicability of these assays. These optimized qPCR assays provide a cost-effective and time-saving method for quantification of bacterial burdens in tissues and body fluids to assess the effectiveness of candidate vaccines or interventions.


Subject(s)
Staphylococcus saprophyticus/genetics , Urinary Tract Infections/microbiology , Uropathogenic Escherichia coli/genetics , Animals , Female , Humans , Mice , Molecular Typing , Real-Time Polymerase Chain Reaction , Reproducibility of Results , Sensitivity and Specificity , Staphylococcus saprophyticus/classification , Staphylococcus saprophyticus/isolation & purification , Uropathogenic Escherichia coli/classification , Uropathogenic Escherichia coli/isolation & purification
15.
Nanomedicine ; 10(1): 159-66, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23891989

ABSTRACT

Rapid detection of bacterial pathogens is critical toward judicious management of infectious diseases. Herein, we demonstrate an in situ electrokinetic stringency control approach for a self-assembled monolayer-based electrochemical biosensor toward urinary tract infection diagnosis. The in situ electrokinetic stringency control technique generates Joule heating induced temperature rise and electrothermal fluid motion directly on the sensor to improve its performance for detecting bacterial 16S rRNA, a phylogenetic biomarker. The dependence of the hybridization efficiency reveals that in situ electrokinetic stringency control is capable of discriminating single-base mismatches. With electrokinetic stringency control, the background noise due to the matrix effects of clinical urine samples can be reduced by 60%. The applicability of the system is demonstrated by multiplex detection of three uropathogenic clinical isolates with similar 16S rRNA sequences. The results demonstrate that electrokinetic stringency control can significantly improve the signal-to-noise ratio of the biosensor for multiplex urinary tract infection diagnosis. FROM THE CLINICAL EDITOR: Urinary tract infections remain a significant cause of mortality and morbidity as secondary conditions often related to chronic diseases or to immunosuppression. Rapid and sensitive identification of the causative organisms is critical in the appropriate management of this condition. These investigators demonstrate an in situ electrokinetic stringency control approach for a self-assembled monolayer-based electrochemical biosensor toward urinary tract infection diagnosis, establishing that such an approach significantly improves the biosensor's signal-to-noise ratio.


Subject(s)
Biomarkers/urine , Biosensing Techniques , RNA, Ribosomal, 16S/genetics , Urinary Tract Infections/diagnosis , Enterococcus faecalis/genetics , Enterococcus faecalis/isolation & purification , Escherichia coli/genetics , Escherichia coli/isolation & purification , Humans , Phylogeny , Proteus mirabilis/genetics , Proteus mirabilis/isolation & purification , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/isolation & purification , Staphylococcus saprophyticus/genetics , Staphylococcus saprophyticus/isolation & purification , Urinary Tract Infections/genetics , Urinary Tract Infections/microbiology , Urine Specimen Collection
16.
Article in English | MEDLINE | ID: mdl-24398486

ABSTRACT

PURPOSE: To evaluate the results of conjunctival culture in patients with nasolacrimal duct obstruction (NLDO) and its changes after successful dacryocystorhinostomy surgery. METHODS: In this prospective study, 71 adult patients with NLDO and 41 age- and sex-matched controls without NLDO were evaluated. The patients were divided in 2 groups based on clinical examination; group A with purulent regurgitation and group B without purulent regurgitation. Dacryocystorhinostomy surgery was performed, and the silicon tube was inserted in patients with upper lacrimal drainage system stenosis and when the lacrimal sac or nasal mucosal flap was inadequate for suitable anastomosis. Before surgery, microbiologic specimens were taken from the conjunctiva. Postoperative conjunctival sampling was continued weekly until the culture became negative or the colony count reached to the range of the control group. RESULTS: There were 38 and 33 patients in groups A and B, respectively. Silicone tube was inserted for 17 patients (23.9%). The culture was positive for bacterial growth in all cases. The conjunctival culture in the control group was positive in 17 eyes (41.4%). The mean count of colonies in a sample unit was 5274 ± 6300, 1167 ± 1504, and 9.5 ± 1.5 for group A, group B, and controls, respectively. The mean time of normalization of specimens was 3.3 ± 1.3 weeks (range 1-7). Pathogenic bacterial growth, higher colony counts, the presence of silicone tube, and purulent regurgitation were significantly associated with longer normalization time (p = 0.007, p = 0.0001, p = 0.0001, and p = 0.01, respectively). CONCLUSIONS: This study suggests that after successful dacryocystorhinostomy surgery, a waiting period of 7 weeks is enough for conjunctival bacterial cultures to become negative or reach the level of the normal eyes.


Subject(s)
Conjunctiva/microbiology , Eye Infections, Bacterial/microbiology , Lacrimal Duct Obstruction/microbiology , Nasolacrimal Duct/microbiology , Staphylococcal Infections/microbiology , Staphylococcus epidermidis/isolation & purification , Staphylococcus saprophyticus/isolation & purification , Case-Control Studies , Colony Count, Microbial , Dacryocystorhinostomy , Eye Infections, Bacterial/surgery , Female , Humans , Intubation , Male , Middle Aged , Nasolacrimal Duct/surgery , Prospective Studies , Silicone Elastomers , Staphylococcal Infections/surgery , Time Factors
17.
Braz J Microbiol ; 55(2): 1507-1519, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38468117

ABSTRACT

Bioremediation of surfactants in water bodies holds significant ecological importance as they are contaminants of emerging concern posing substantial threats to the aquatic environment. Microbes exhibiting special ability in terms of bioremediation of contaminants have always been reported to thrive in extraordinary environmental conditions that can be extreme in terms of temperature, lack of nutrients, and salinity. Therefore, in the present investigation, a total of 46 bacterial isolates were isolated from the Indian sector of the Southern Ocean and screened for degradation of sodium dodecyl sulphate (SDS). Further, two Gram-positive psychrotolerant bacterial strains, ASOI-01 and ASOI-02 were identified with significant SDS degradation potential. These isolates were further studied for growth optimization under different environmental conditions. The strains were characterized as Staphylococcus saprophyticus and Bacillus pumilus based on morphological, biochemical, and molecular (16S RNA gene) characteristics. The study reports 88.9% and 93.4% degradation of SDS at a concentration of 100 mgL-1, at 20 °C, and pH 7 by S. saprophyticus ASOI-01 and B. pumilus ASOI-02, respectively. The experiments were also conducted in wastewater samples where a slight reduction in degradation efficiency was observed with strains ASOI-01 and ASOI-02 exhibiting 76.83 and 64.93% degradation of SDS respectively. This study infers that these bacteria can be used for the bioremediation of anionic surfactants from water bodies and establishes the potential of extremophilic microbes for the utilization of sustainable wastewater management.


Subject(s)
Bacillus pumilus , Biodegradation, Environmental , Seawater , Sodium Dodecyl Sulfate , Staphylococcus saprophyticus , Sodium Dodecyl Sulfate/metabolism , Bacillus pumilus/genetics , Bacillus pumilus/metabolism , Bacillus pumilus/isolation & purification , Bacillus pumilus/classification , Staphylococcus saprophyticus/genetics , Staphylococcus saprophyticus/isolation & purification , Staphylococcus saprophyticus/metabolism , Staphylococcus saprophyticus/classification , Seawater/microbiology , Surface-Active Agents/metabolism , Phylogeny , RNA, Ribosomal, 16S/genetics , Water Pollutants, Chemical/metabolism , Wastewater/microbiology
18.
J Clin Microbiol ; 51(5): 1563-6, 2013 May.
Article in English | MEDLINE | ID: mdl-23390286

ABSTRACT

Among 30 urinary isolates of Staphylococcus saprophyticus identified by sequencing methods, the rate of accurate identification was 100% for Bruker Biotyper matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), 86.7% for the Phoenix PID and Vitek 2 GP systems, 93.3% for the MicroScan GP33 system, and 46.7% for the BBL CHROMagar Orientation system.


Subject(s)
Bacterial Typing Techniques , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Staphylococcal Infections/diagnosis , Staphylococcus saprophyticus/classification , Staphylococcus saprophyticus/isolation & purification , Urine/microbiology , Base Sequence , Humans , Sequence Analysis, DNA
19.
J Infect Chemother ; 19(3): 393-403, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23640203

ABSTRACT

The Japanese surveillance committee conducted the first nationwide surveillance of antimicrobial susceptibility patterns of uropathogens responsible for female acute uncomplicated cystitis at 43 hospitals throughout Japan from April 2009 to November 2010. In this study, the causative bacteria (Escherichia coli and Staphylococcus saprophyticus) and their susceptibility to various antimicrobial agents were investigated by isolation and culturing of bacteria from urine samples. In total, 387 strains were isolated from 461 patients, including E. coli (n = 301, 77.8 %), S. saprophyticus (n = 20, 5.2 %), Klebsiella pneumoniae (n = 13, 3.4 %), and Enterococcus faecalis (n = 11, 2.8 %). S. saprophyticus was significantly more common in premenopausal women (P = 0.00095). The minimum inhibitory concentrations of 19 antibacterial agents used for these strains were determined according to the Clinical and Laboratory Standards Institute manual. At least 87 % of E. coli isolates showed susceptibility to fluoroquinolones and cephalosporins, and 100 % of S. saprophyticus isolates showed susceptibility to fluoroquinolones and aminoglycosides. The proportions of fluoroquinolone-resistant E. coli strains and extended-spectrum ß-lactamase (ESBL)-producing E. coli strains were 13.3 % and 4.7 %, respectively. It is important to confirm the susceptibility of causative bacteria for optimal antimicrobial therapy, and empiric antimicrobial agents should be selected by considering patient characteristics and other factors. However, the number of isolates of fluoroquinolone-resistant or ESBL-producing strains in gram-negative bacilli may be increasing in patients with urinary tract infections (UTIs) in Japan. Therefore, these data present important information for the proper treatment of UTIs and will serve as a useful reference for future surveillance studies.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Infections/microbiology , Cystitis/microbiology , Escherichia coli/drug effects , Staphylococcus saprophyticus/drug effects , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Infections/epidemiology , Cystitis/epidemiology , Escherichia coli/isolation & purification , Female , Humans , Japan/epidemiology , Male , Microbial Sensitivity Tests , Middle Aged , Public Health Surveillance , Staphylococcus saprophyticus/isolation & purification
20.
Mem Inst Oswaldo Cruz ; 108(1): 73-6, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23440118

ABSTRACT

The epidemiology of urinary tract infections (UTI) by Staphylococcus saprophyticus has not been fully characterised and strain typing methods have not been validated for this agent. To evaluate whether epidemiological relationships exist between clusters of pulsed field gel-electrophoresis (PFGE) genotypes of S. saprophyticus from community-acquired UTI, a cross-sectional surveillance study was conducted in the city of Rio de Janeiro, Brazil. In total, 32 (16%) female patients attending two walk-in clinics were culture-positive for S. saprophyticus. Five PFGE clusters were defined and evaluated against epidemiological data. The PFGE clusters were grouped in time, suggesting the existence of community point sources of S. saprophyticus. From these point sources, S. saprophyticus strains may spread among individuals.


Subject(s)
Staphylococcal Infections/microbiology , Staphylococcus saprophyticus/isolation & purification , Urinary Tract Infections/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Typing Techniques , Brazil/epidemiology , Child , Child, Preschool , Cluster Analysis , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Cross-Sectional Studies , Electrophoresis, Gel, Pulsed-Field , Female , Humans , Infant , Middle Aged , Population Surveillance , Pregnancy , Staphylococcal Infections/epidemiology , Staphylococcus saprophyticus/classification , Urinary Tract Infections/epidemiology , Young Adult
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