scholarly journals Inducible and constitutive clindamycin resistance in Staphylococcus aureus in a northeastern Indian tertiary care hospital

2015 ◽  
Vol 9 (07) ◽  
pp. 725-731 ◽  
Author(s):  
Amit Banik ◽  
Annie Bakorlin Khyriem ◽  
Jeetendra Gurung ◽  
Valarie Wihiwot Lyngdoh

Introduction: Staphylococcus aureus is one of the most common pyogenic bacteria. They are notorious for developing prompt resistance to newer antimicrobials. With increasing incidence of methicillin-resistant S. aureus (MRSA) isolates, the treatment options are also becoming limited. Clindamycin is an excellent drug for skin and soft tissue infections, but resistance mediated by the inducible phenotype (iMLSB) leads to in vivo therapeutic failure even though there may be in vitro susceptibility. The double disk approximation test (D-test) can reliably detect the presence of such isolates. This study was aimed to detect and report the prevalence of the iMLSB phenotype in NEIGRIHMS, a tertiary care center in Northeast India. Methodology: A total of 243 consecutive isolates were subjected to routine identification tests followed by antimicrobial sensitivity testing. Erythromycin-resistant isolates were tested for inducible resistance phenotype by the D-test. Results: Among strains tested, 95 (39%) were erythromycin resistant. Twenty-six (10.7%) isolates were D-test positive (iMLSB phenotype), 41 (16.88%) were constitutively resistant (cMLSB phenotype), and 28 isolates (11.52%) were found to be negative by D-test. The incidence of both inducible and constitutive phenotypes was higher in MRSA isolates compared to methicillin-sensitive S. aureus (MSSA) isolates. Conclusions: This study revealed a moderate prevalence of the inducible clindamycin phenotype in the staphylococcal isolates tested. Clinical microbiology laboratories in areas of high MRSA prevalence should consider performing the D-test routinely. This will help prevent prescription of drug(s) whose therapeutic efficacy is doubtful.

Author(s):  
R. Shakthi D. Venkatesha

Methicillin resistant Staphylococcus aureus (MRSA) has emerged as one of the commonest causes of hospital acquired infections. Vancomycin is the drug of choice for the treatment of MRSA. Increase in Minimum inhibitory concentration (MIC) of Vancomycin has been observed in both Methicillin sensitive and resistant Staphylococcal isolates. In critically ill patients, Vancomycin has become a poor therapeutic antibiotic whereas; Linezolid has emerged as an alternative drug in treating such patients. This study was undertaken to determine the sensitivity pattern among clinical isolates of Staphylococcus aureus (S. aureus) to Vancomycin and Linezolid, in order to formulate a better treatment.100 S. aureuswere isolated from various clinical specimens. Antibiotic sensitivity testing was performed by Kirby Bauer disc diffusion method and MICs of Vancomycin and Linezolid were determined by E-test following CLSI guidelines. Out of 100 S. aureus isolated, 68 were MRSA strains. Among 68 strains of MRSA for which MIC levels of Vancomycin 4 µg/ml, 2µg/ml and 1 µg/ml were 4, 27, and 37 respectively. Similarly, out of total MRSA strains MIC levels of Linezolid 4 µg/ml, 2µg/ml and 1 µg/ml were 1, 25, and 42 respectively. All 100 strains showed similar in-vitro efficacy for Vancomycin and Linezolid by Kirby Bauer disc diffusion method, but the number of strains with higher ranges of MICs of Vancomycin were more as compared to those which had higher ranges of MICs for Linezolid. Hence we suggest that Linezolid can be used as an alternative for the treatment of MRSA.


2020 ◽  
Vol 12 (03) ◽  
pp. 230-232
Author(s):  
Dhruv Mamtora ◽  
Sanjith Saseedharan ◽  
Ritika Rampal ◽  
Prashant Joshi ◽  
Pallavi Bhalekar ◽  
...  

Abstract Background Blood stream infections (BSIs) due to Gram-positive pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) are associated with high mortality ranging from 10 to 60%. The current anti-MRSA agents have limitations with regards to safety and tolerability profile which limits their prolonged usage. Levonadifloxacin and its oral prodrug alalevonadifloxacin, a novel benzoquinolizine antibiotic, have recently been approved for acute bacterial skin and skin structure infections including diabetic foot infections and concurrent bacteremia in India. Methods The present study assessed the potency of levonadifloxacin, a novel benzoquinolizine antibiotic, against Gram-positive blood stream clinical isolates (n = 31) collected from January to June 2019 at a tertiary care hospital in Mumbai, India. The susceptibility of isolates to antibacterial agents was defined following the Clinical and Laboratory Standard Institute interpretive criteria (M100 E29). Results High prevalence of MRSA (62.5%), quinolone-resistant Staphylococcus aureus (QRSA) (87.5%), and methicillin-resistant coagulase-negative staphylococci (MR-CoNS) (82.35%) were observed among bacteremic isolates. Levonadifloxacin demonstrated potent activity against MRSA, QRSA, and MR-CoNS strains with significantly lower minimum inhibitory concentration MIC50/90 values of 0.5/1 mg/L as compared with levofloxacin (8/32 mg/L) and moxifloxacin (2/8 mg/L). Conclusion Potent bactericidal activity coupled with low MICs support usage of levonadifloxacin for the management of BSIs caused by multidrug resistant Gram-positive bacteria.


2020 ◽  
Vol 12 (04) ◽  
pp. 233-238
Author(s):  
Ashvini K. Yadav ◽  
Suneel Bhooshan ◽  
Allen Johnson ◽  
Dinesh P. Asati ◽  
Shashwati Nema ◽  
...  

Abstract Purpose Cutibacterium acnes (C. acnes) is an emerging pathogen that is highly resistant to antibiotics and is capable of causing persistent infections that are difficult to treat. Methods & Materials Acne vulgaris patients visiting dermatology OPD of our tertiary care hospital during the study period of 2 months were recruited. Skin swabs were collected, and the sample was processed on 5% sheep-blood agar for anaerobic culture by the GasPak method. Isolates were identified by the standard biochemical test. Antimicrobial susceptibility testing was performed for clinically relevant antibiotics by the E-strip method. The clinical response was evaluated after 1-month follow-up to the prescribed antibiotics. Results Minocycline, doxycycline, ceftriaxone, and tetracycline were the most effective antibiotics. Nonsusceptibility to clindamycin and erythromycin were observed in 11.9% and 31% isolates, respectively, with 9.5% isolates being nonsusceptible to both. For none of the antibiotics we found significant difference in the proportion of susceptible and nonsusceptible isolates between mild, moderate, and severe grades of acne vulgaris. For none of the antibiotic regimens, significant difference was observed between nonresponders and responders. Twenty-seven patients received clindamycin and among them 16 of 19 responders and 6 of 8 nonresponders yielded growth of clindamycin-susceptible isolates (p = 0.57). Conclusion We observed significant prevalence of resistant strains of C. acnes among patients with acne vulgaris. No association was observed between in vitro susceptibility results and treatment outcome.


1996 ◽  
Vol 30 (5) ◽  
pp. 469-472
Author(s):  
Tsong-Mei Tsai ◽  
Brian F Shea ◽  
Paul F Souney ◽  
Fred G Volinsky ◽  
Joseph M Scavone ◽  
...  

OBJECTIVE: TO study the effects of ofloxacin on the reliability of urine glucose testing. DESIGN: Open-label, nonrandomized. SETTING: A university-affiliated tertiary care hospital, ambulatory clinic. PARTICIPANTS: Ten healthy volunteers (8 men and 2 women) aged 22-39 years. MAIN OUTCOME MEASURES: Phase I (in vitro) involved the addition of selected amounts of ofloxacin to a set of standard 50-mL urine samples prepared to simulate glycosuria. Phase II (in vivo) involved the oral administration of ofloxacin 400 mg to 10 subjects. Urine was collected: (1) immediately predose, (2) pooled 0–4 hours postdose, and (3) pooled 4–8 hours postdose. Known glucose concentrations were then added to these samples. Clinitest and Diastix tests were performed on all samples. The accuracy of these tests in determining glucose concentrations was compared among urine samples taken before and after ofloxacin dosing. RESULTS: None of the ofloxacin concentrations in phase I (0,25,50, 100, 200,400, and 800 μg/mL) influenced these testing methods at the urine glucose concentrations of 0.0%, 0.5%, 1%, and 2%. Likewise, the accuracy of these two tests was unaffected by ofloxacin administration in phase II. CONCLUSIONS: In single-dose administration, ofloxacin does not interfere with Clinitest or Diastix for determining urine glucose concentrations. Supported by a grant from the RW Johnson Pharmaceutical Research Institute. Presented in abstract form at the American College of Clinical Pharmacy 1994 Winter Practice and Research Forum, February 6–9, 1994, San Diego. CA.


Author(s):  
Yamuna Devi Bakthavatchalam ◽  
Abirami Shankar ◽  
Rajeshwari Muniyasamy ◽  
John Victor Peter ◽  
Zervos Marcus ◽  
...  

Abstract Objectives Levonadifloxacin (WCK 771; IV) and its prodrug alalevonadifloxacin (WCK 2349; oral) are benzoquinolizine fluoroquinolones, recently approved in India for the treatment of acute bacterial skin and skin structure infections with concurrent bacteraemia and diabetic foot infections. Ahead of its market launch, the present study aimed to assess the in vitro activity of levonadifloxacin against contemporary Staphylococcus aureus isolates collected from a large tertiary care hospital in India. Additionally, levonadifloxacin activity was tested against hVISA and Bengal Bay clone MRSA isolates. Methods Non-duplicate S. aureus (n = 793) isolates collected at Christian Medical College hospital, Vellore, India during 2013–19 were included in the study. MRSA isolates were identified using a cefoxitin disc diffusion assay. MICs of levonadifloxacin and comparator antibiotics were determined using the broth microdilution method. Mutations in QRDRs were identified for selected levofloxacin-non-susceptible isolates. MLST profiling was undertaken to detect the Bengal Bay clone. Results Among the 793 isolates, 441 (55.6%) were MRSA and 626 (78.9%) were non-susceptible to levofloxacin. Levonadifloxacin showed MIC50 and MIC90 values of 0.25 and 0.5 mg/L, respectively, for all S. aureus, which included hVISA and Bengal Bay clone MRSA. The potency of levonadifloxacin was 16 times superior compared with levofloxacin. Conclusions The present study demonstrated potent activity of levonadifloxacin against contemporary S. aureus isolates, which included MRSA isolates, hVISA isolates, Bengal Bay clone isolates and a high proportion of quinolone-non-susceptible isolates. The potent activity of levonadifloxacin observed in this study supports its clinical use for the treatment of S. aureus infections.


2018 ◽  
Vol 72 (2) ◽  
pp. 181-184
Author(s):  
Saugata Choudhury ◽  
Lee Kar Mun ◽  
Esme Ng Chu Xuan ◽  
Lee Shin Jia ◽  
Shawn Vasoo ◽  
...  

We compared the in vitro antimicrobial activities of tedizolid and linezolid on the Sensititre broth microdilution system for Gram-positive cocci isolates (n=146) from skin and skin structure infections and bloodstream infections, bronchoalveolar lavage and sputum. These pathogens included 40 methicillin-resistant Staphylococcus aureus, 38 coagulase-negative staphylococci, 20 Enterococcus faecalis and 48 beta-haemolytic Streptococcus spp. Susceptibility was simultaneously determined for 48 vanA vancomycin-resistant enterococci isolates 2013–2016 from rectal swabs (23 E. faecalis and 25 E. faecium, of which 4 were linezolid-non-susceptible). MIC90s for tedizolid were fourfold to eightfold lower than linezolid on the Sensititre and ranged from 0.12 to 0.5 µg/mL for the different pathogen groups. All isolates were susceptible to tedizolid except two vanA E. faecium strains (MICs of 1 and 2 µg/mL, respectively). Categorical and essential agreement for tedizolid were 99.48% and 92%, respectively, between Liofilchem gradient diffusion and Sensititre methods. Overall, the drug exhibited excellent activity against the surveyed Gram-positive pathogens.


Author(s):  
Aneela Khawaja ◽  
Asma Ejaz ◽  
. Abeer ◽  
Faiqa Arshad ◽  
Zaheer Saleem ◽  
...  

Background: Staphylococcus aureus (SA) is a major etiological pathogen causing multiple infections and broadly known as a serious public health challenge faced due to antibiotic resistance. It is the need of time that infection prevention and control strategies; and antibiotic stewardship policies have to be employed conjointly to minimize the extended rise of antibiotic resistance. Objectives: To determine the frequency and sensitivity patterns of Staphylococcus aureus in tertiary care setting. Study Design: Descriptive study Place & Duration of Study: Pathology Laboratory of tertiary care center from 1st March’ 2020 till 28th February’ 2021. Materials & Methods: A total 643 Staph. aureus isolated from various clinical specimens received in a tertiary care hospital; were processed and identified by culture, staining and bench tests. Sensitivity testing was done by Disc Diffusion method. Resistance to cefoxitin(30µg) was labelled as Methicillin Resistant Staphylococcus aureus (MRSA). Constitutive and Inducible Clindamycin resistance was also evaluated. (CLSI, 2020-21). Results: During the study period 125 (19.44%) MRSA were recovered. Statistically, gender distribution regarding MRSA was significant, most of SA was recovered from blood (53.68%), while 46.31% from pus and wound swabs. The frequency of MRSA from Surgical and allied wards was higher (52.63%) than Medicine and allied wards (47.36%). Sensitivity to vancomycin, linezolid and tigecycline was noted 100% by all the isolates. Sensitivity to clindamycin and Doxycycline was 68.42% and 64.81% respectively; while resistance to erythromycin, ciprofloxacin and trimethoprim/sulfamethoxazole was 73.68%, 60% and 57.89%, respectively. Conclusion: The hazardous infections due to Staphylococcus aureus are worrisome in the present therapeutic scenario. A levelheaded prescription of sensitive antibiotics has to be ensured to minimize the rising frequency of resistant strains of SA.


Sign in / Sign up

Export Citation Format

Share Document