Inducible Clindamycin Resistance and Biofilm Production among Staphylococci Isolated from Tertiary Care Hospitals in Nepal

Resistance to antibiotics, biofilm formation and the presence of virulence factors play important roles in increased mortality associated with infection by staphylococci. The macrolide lincosamide streptogramin B (MLSB) family of antibiotics is commonly used to treat infections by methicillin-resistant isolates. Clinical failure of clindamycin therapy has been reported due to multiple mechanisms that confer resistance to MLSB. This study aims to find the incidence of different phenotypes of MLSB resistance and biofilm production among staphylococci. A total of 375 staphylococci were isolated from different clinical samples, received from two tertiary care hospitals in Nepal. Methicillin resistance was detected by cefoxitin disc diffusion method and inducible clindamycin resistance by D test, according to CLSI guidelines. Biofilm formation was detected by the tissue culture plate method and PCR was used to detect ica genes. Of the total staphylococci isolates, 161 (42.9%) were Staphylococcus aureus, with 131 (81.4%) methicillin-resistant strains, and 214 (57.1%) isolates were coagulase-negative staphylococci, with 143 (66.8%) methicillin-resistant strains. The overall prevalence of constitutive MLSB (cMLSB) and inducible MLSB (iMLSB) phenotypes was 77 (20.5%) and 87 (23.2%), respectively. Both iMLSB and cMLSB phenotypes predominated in methicillin-resistant isolates. The tissue culture plate method detected biofilm formation in 174 (46.4%) isolates and ica genes in 86 (22.9%) isolates. Among biofilm producing isolates, cMLSB and iMLSB phenotypes were 35 (20.1%) and 27 (15.5%), respectively. The cMLSB and iMLSB were 11 (12.8%) and 19 (22.1%), respectively, in isolates possessing ica genes. Clindamycin resistance in the form of cMLSB and iMLSB, especially among MRSA, emphasizes the need for routine D tests to be performed in the lab.

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Assessment of Biofilm Formation among the Clinical Isolates of Escherichia coli in a Tertiary Care Hospital

Microbiology Research Journal International ◽

10.9734/mrji/2020/v30i130187 ◽

2020 ◽

pp. 26-32

Author(s):

Bedobroto Biswas ◽

Naik Shalini Ashok ◽

Deepesh Nagarajan ◽

Md Zaffar Iqubal

Keyword(s):

Escherichia Coli ◽

Tissue Culture ◽

Biofilm Formation ◽

Tertiary Care ◽

Clinical Samples ◽

Care Hospital ◽

Plate Method ◽

Culture Plate ◽

Tissue Culture Plate

Aims: Identification and grading of the Escherichia coli according to their biofilm production capability. Study Design: Cross-sectional study. Place and Duration of Study: This was conducted in Department Microbiology at M.S. Ramaiah Medical college and Hospital, Bengaluru from March 2017 to August 2017. Methodology: A total of 55 non repetitive Escherichia coli isolates were identified from various clinical samples like urine, pus ,tissue and peritoneal fluids .All the organisms were isolated in pure culture and biofilm formation was detected in vitro by Gold standard TCP (Tissue culture plate) method. Organisms were incubated for an extended period of 48 hours and the biofilms were detected by acetone alcohol elution method. Organisms were categorized as strong, moderate, weak and no biofilm producers based on the obtained OD value of the elute. Results: Majority of the isolates of Escherichia coli were obtained from catheterized urine culture (67.03%) followed by pus (25.50%).Most of the isolates were capable of forming biofilm in vitro by tissue culture plate method except a few (9.1%). 40% of the isolates were strong biofilm formers which had >4 ODC. 25.5% showed medium biofilm-forming capability and rest 25.5% showed weak biofilm formations in vitro. Conclusion: The ability to form biofilm from a species can give us a better understanding of the biofilm-related infections pertaining to the particular group. Detection of biofilms remains a most important determinant to approximate the incidence of such infections. Categorization of organisms according to their biofilm formation may help us understand the frequency of biofilm-associated infections, and thus take necessary precautions to avoid the problem. Further studies involving the detection of biofilm may be conducted and the tests can be implemented in routine diagnostic microbiology to assess the usefulness of the methods in detection of biofilm-related infections.

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Acinetobacter baumannii: Identification, Antibiotic Sensitivity and Biofilm Formation in Different Clinical Samples

Bangladesh Journal of Medical Microbiology ◽

10.3329/bjmm.v12i2.51690 ◽

2018 ◽

Vol 12 (2) ◽

pp. 4-9

Author(s):

Maherun Nesa ◽

Shaheda Anwar ◽

Ahmed Abu Saleh

Keyword(s):

Tissue Culture ◽

Acinetobacter Baumannii ◽

Pleural Fluid ◽

Biofilm Formation ◽

Antibiotic Sensitivity ◽

Tracheal Aspirate ◽

Clinical Samples ◽

Plate Method ◽

Acinetobacter Spp ◽

Tissue Culture Plate

Background: Acinetobacter baumannii is responsible for nosocomial infections which are related to biofilm formation of this pathogen. Biofilm formation helps the bacteria in surviving stressed environmental conditions and bacteria growing in biofilms are resistant to most of the commonly used antibiotics. Objectives: The objective of this study was to detect A. baumannii, to see antibiotic sensitivity and biofilm formation in different clinical samples. Methods: Total 108 Acinetobacter spp. were collected from different clinical samples which were identified by conventional microbiological procedures. Out of 108 Acinetobacter spp, 85 were identified as A. baumannii by polymerase chain reaction by detecting blaOXA-51 gene which is intrinsic to A. baumannii. Antibiotic sensitivity was detected by modified disc diffusion method and biofilm formation was detected by Tissue culture plate method. Results: Among 85 isolates, 45.9% A. baumannii were obtained from tracheal aspirate followed by blood (21.2%), wound swab (15.3%), urine (10.6%), pus (5.9%) and pleural fluid (1.1%). More than 80% 0f A. baumannii was resistant to cephalosporin, aminoglycosides, quinolone, carbapenem. By Tissue culture plate method, 78.8% of isolates showed biofilm formation. Biofilm formation in tracheal aspirate was 82.1%, in blood 72%, in wound swab 92%, in urine 44.4%, in pus 100% and in pleural fluid 100%. Conclusion: Detection rate of A. baumannii was more in tracheal aspirates. Biofilm producing A. Baumannii was resistant to most of the antibiotics. Bangladesh J Med Microbiol 2018; 12 (2): 4-9

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Tube method and Congo red agar versus tissue culture plate method for detection of biofilm production by uropathogens isolated from midstream urine: Which one could be better?

African Journal of Clinical and Experimental Microbiology ◽

10.4314/ajcem.v20i1.9 ◽

2018 ◽

Vol 20 (1) ◽

pp. 60

Author(s):

A. M. Sultan ◽

Y. Nabiel

Keyword(s):

Tissue Culture ◽

Congo Red ◽

Plate Method ◽

Biofilm Production ◽

Culture Plate ◽

Tissue Culture Plate

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Biofilm formation by bacteria isolated from intensive care units of a tertiary care hospital, with special relevance to its risk factors

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20213915 ◽

2021 ◽

Vol 9 (10) ◽

pp. 2959

Author(s):

Mayuri Gogoi ◽

Ajanta Sharma

Keyword(s):

Risk Factors ◽

Tissue Culture ◽

Intensive Care ◽

Biofilm Formation ◽

P Value ◽

Bacterial Isolates ◽

Plate Method ◽

Culture Plate ◽

Tissue Culture Plate ◽

Device Associated Infection

Background: The purpose of this study was to detect biofilm formation by bacterial isolates from patients with device associated infection admitted in intensive care units (ICUs), to compare the three methods used for detection of bioiflm, to compare the antimicrobial susceptibility pattern of the biofilm producers with the non-producers and to study the risk factors associated with biofilm formation.Methods: A total of 115 bacterial isolates from patients with device associated infection admitted in different ICU for a period of one year was included in the study. These clinical isolates were detected for biofilm formation by tissue culture plate method, tube method and Congo red agar method. Kirby-Bauer disc diffusion method of antibiotic susceptibility was performed on all isolates.Results: Out of the 115 bacterial isolates, 71 were biofilm producers. Tissue culture plate method detected the maximum number of biofilm producers (61.7%). The maximum number of biofilm producers were isolated from tracheal aspirate and endotracheal tubes (52.1%) followed by blood (17%) and urine (12.6%) respectively. The predominant biofilm producing isolates were Klebsiella pneumoniae (39.4%), Staphylococcus aureus (19.7%) and Pseudomonas aeruginosa (16.9%). Multi drug resistance among the biofilm producers was significantly higher than the non-biofilm producers (p value=0.0125). The risk of biofilm formation was seen to increase with the increase in duration of hospital stay (p value=0.0092, statistically very significant).Conclusions: From this study it was found that a high degree of biofilm producers were isolated from patients on indwelling devices. Tissue culture plate was found to be the most accurate method. The degree of multidrug resistance among the bioiflm producers was significantly higher than the non-producers.

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Antibiotic Resistance Profile and Biofilm Production of Staphylococcus pseudintermedius Isolated from Dogs in Thailand

Pharmaceuticals ◽

10.3390/ph14060592 ◽

2021 ◽

Vol 14 (6) ◽

pp. 592

Author(s):

Pavarish Jantorn ◽

Hawaree Heemmamad ◽

Tanawan Soimala ◽

Saowakon Indoung ◽

Jongkon Saising ◽

...

Keyword(s):

Antibiotic Resistance ◽

Meca Gene ◽

Staphylococcus Pseudintermedius ◽

Methicillin Resistant ◽

Antibiotic Resistance Profile ◽

Biofilm Production ◽

Southern Thailand ◽

Life Threatening ◽

Suitable Treatment ◽

Resistant Strains

Staphylococcus pseudintermedius is a zoonotic pathogen that can cause life-threatening infections in animals and humans. The study of methicillin-resistant S. pseudintermedius (MRSP) and its ability to produce biofilms is important to select the most suitable treatment. The prevalence and characteristics of S. pseudintermedius isolated from dogs admitted at the Veterinary Teaching Hospital, Prince of Songkla University, Thailand were assessed. Results showed that 28.30% (15/53) of the isolates were MRSP. Amplification of the mecA gene was observed in 93.33% (14/15) MRSP. Methicillin-resistant strains revealed co-resistant patterns against other antibiotics, including chloramphenicol, clindamycin, tetracycline, clarithromycin, ciprofloxacin, and trimethoprim. In this study, all bacterial isolates produced biofilms, while 90.55% of S. pseudintermedius isolates were strong or moderate biofilm producers. Most (45–60%) of the resistant strains were strong biofilm producers, while the correlation between biofilm production and antibiotic resistance was not statistically significant. This is the first study in southern Thailand to investigate the drug-resistant profile of S. pseudintermedius and its ability to form biofilm. The results will contribute to a better understanding of the emergence and prevalence of antimicrobial resistance in S. pseudintermedius.

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Methicillin-Resistant Staphylococcus aureus in Two Tertiary-Care Centers in Jeddah, Saudi Arabia

Infection Control and Hospital Epidemiology ◽

10.1086/501891 ◽

2001 ◽

Vol 22 (4) ◽

pp. 211-216 ◽

Cited By ~ 25

Author(s):

Tariq A. Madani ◽

Nabeela A. Al-Abdullah ◽

Ali A. Al-Sanousi ◽

Tawfik M. Ghabrah ◽

Shadia Z. Afandi ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Saudi Arabia ◽

Tertiary Care ◽

Age Groups ◽

Clinical Manifestations ◽

Total Mortality ◽

Control Measures ◽

Methicillin Resistant ◽

Mrsa Infection ◽

Tertiary Care Hospitals

AbstractObjective:To review clinical experience with methicillin-resistant Staphylococcus aureus (MRSA) in tertiary-care hospitals in Jeddah, Saudi Arabia.Design:Retrospective review for the year 1998.Setting:Two tertiary-care hospitals.Methods:Results of MRSA-positive cultures of clinical specimens obtained as part of investigations for suspected infections were retrieved from the microbiology laboratories' records. Charts of patients were reviewed, with standardized data collection.Results:Of 673 S aureus isolates identified, 222 (33%, or 6.8 isolates/1,000 admissions) were MRSA Overall MRSA prevalence was 2% in 1988. Nosocomial acquisition occurred in 84.2% of cases. All age groups were affected, and 52% of patients had at least one comorbidity. MRSA prevalence was highest in the intensive care units (26.6% of all isolates), the medical wards (24.8%), and the surgical wards (19.8%). Seventy-three percent of isolates caused infection; the rest represented colonization. Surgical wounds (35.2%), the chest (29%), and central venous catheters (13%) were the most common sites of infection. Bacteremia occurred in 15.4% of patients. Local signs (84%) and fever (75.9%) were the most common clinical manifestations. Respiratory distress and septic shock occurred in 30.2% and 13.6% of cases, respectively. Of 162 patients with MRSA infection and 60 patients with MRSA colonization, 95.7% and 70% received antibiotics in the preceding 6 weeks, respectively (P<.0001). The total mortality of patients with MRSA infection was 53.7%: 36.4% as a result of MRSA infection and 17.3% as a result of other causes.Conclusions:The prevalence of MRSA is high and rapidly increasing in the two hospitals, as it is worldwide. Control measures to prevent die spread of MRSA in hospitals should continue, with reinforcement of hygienic precautions and development of policies to restrict the use of antibiotics.

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The Staphylococcal Cassette Chromosome mec (SCCmec) Analysis and Biofilm Formation of Methicillin-Resistant Staphylococcus cohnii Isolated from Clinical Samples in Tehran, Iran

Recent Patents on Anti-Infective Drug Discovery ◽

10.2174/1574891x16666210210101912 ◽

2021 ◽

Vol 16 ◽

Author(s):

Somaye Delfani ◽

Faranak Rezaei ◽

Setareh Soroush ◽

Pegah Shakib

Keyword(s):

Antibiotic Resistance ◽

Biofilm Formation ◽

Antibiotic Resistance Genes ◽

Mobile Element ◽

Diffusion Method ◽

Clinical Samples ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance ◽

Sccmec Types

Background: Methicillin-resistant coagulase-negative staphylococci is responsible for hospital and community-acquired infections. Objective: This study aimed to investigate the antibiotic-resistance patterns, antibiotic-resistance genes, namely, ermA, ermB, ermC, blaZ, msrA, tetK, tetM, mup, and vanA, biofilm formation, and prevalence of different SCCmec types among the Staphylococcus cohniistrains isolated from clinical samples in Tehran, Iran. Methods: In this study,S. cohniiisolates were screened from the clinical samples from March 2012 to February 2013 in Tehran, Iran.Antimicrobial susceptibility test and inducible clindamycin resistance were evaluated by disc diffusion method, andresistance genes were examined using Polymerase Chain Reaction (PCR) assays. Then, biofilm formation assay was analyzed by Microtiter-plate test to detect the icaA and icaDgenes. The SCCmec and the Arginine Catabolite Mobile Element (ACME) typing were performed using the PCRmethod. Results: FromtwentyS. cohnii, all isolates were resistant to cefoxitin. 95% of the S. cohnii was defined as multidrug resistance (MDR)strains. The ermB, ermC, and vanA genes were not detected in any isolates; however, the blaZ gene had the highest frequency.95% of the S. cohnii isolates produced biofilm. Also, 4 SCCmec types, including V, IV, III+ (C2), VIII+ (AB1), were identified. Therefore, the majority of SCCmec were untypable. Based on the ACME typing, arcA and opp3 genes were positive in 13 (65%) and 1 (5%) isolates, respectively. Conclusion: Due to the high antimicrobial resistance and the spread of untypableSCCmecamong the isolates studied, the control and treatment of methicillin-resistantS. cohnii in hospitals and public health centers is a significant concern.

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Biofilm Formation among Clinical and Food Isolates ofListeria monocytogenes

International Journal of Microbiology ◽

10.1155/2013/524975 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 14

Author(s):

Joana Barbosa ◽

Sandra Borges ◽

Ruth Camilo ◽

Rui Magalhães ◽

Vânia Ferreira ◽

...

Keyword(s):

Tissue Culture ◽

Listeria Monocytogenes ◽

Osmotic Stress ◽

Environmental Conditions ◽

Biofilm Formation ◽

Stress Conditions ◽

Acidic Stress ◽

Biofilm Production ◽

Oflisteria Monocytogenes ◽

Clinical Cases

Objective. A total of 725Listeria monocytogenesisolates, 607 from various foods and 118 from clinical cases of listeriosis, were investigated concerning their ability to form biofilms, at 4°C during 5 days and at 37°C during 24 h.Methods. Biofilm production was carried out on polystyrene tissue culture plates. FiveL. monocytogenesisolates were tested for biofilm formation after being exposed to acidic and osmotic stress conditions.Results. Significant differences (P<0.01) between clinical and food isolates were observed. At 37°C for 24 h, most food isolates were classified as weak or moderate biofilm formers whereas all the clinical isolates were biofilm producers, although the majority were weak. At 4°C during 5 days, 65 and 59% isolates, from food and clinical cases, respectively, were classified as weak. After both sublethal stresses, at 37°C just one of the five isolates tested was shown to be more sensitive to subsequent acidic exposure. However, at 4°C both stresses did not confer either sensitivity or resistance.Conclusions. Significant differences between isolates origin, temperature, and sublethal acidic stress were observed concerning the ability to form biofilms. Strain, origin, and environmental conditions can determine the level of biofilm production byL. monocytogenesisolates.

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