Showing 26 results for Bacteria
Dr. Tahereh Valadbeigi, Dr. Ali Mohammad Bahrami, Dr. Minoo Shaddel,
Volume 2, Issue 2 (4-2014)
Abstract
Introduction: Natural products have been the most successful source of potential drug leads. One of them is lichens, which have been used since antiquity as natural sources of drugs. The aim of this study was to investigate the antibacterial and antifungal activity of different extracts of the Iranian lichens in Ilam Province. Methods: The aqueous, acetone, and methanol extracts of 6 lichen species, including Caloplaca variabilis, Fulgensia subbracteata, Lecanora muralis, Physcia adscendens, Psora decipiens, and Megaspora verrucosa, were produced using Soxhlet extractor. Then, antibacterial and antifungal activities of them against 6 standard strains of bacteria, including Enterococcus faecalis ATCC 2321, Escherichia coli ATCC 1652, Proteus mirabilis ATCC 2601, Salmonella typhi ATCC 1679, Staphylococcus aureus ATCC 1885, and Staphylococcus epidermidis ATCC 2405 and two fungi, including Fusarium moniliforme and Verticillium dahliae, were evaluated using the disc-diffusion method and the minimal inhibitory concentration was determined by broth tube dilution. Streptomycin (10 µg/ml) and ketoconazole (10 µg/ml) were used as positive controls for bacteria and fungi, respectively. Sterile distilled dimethyl sulfoxide (DMSO) was used as negative control. Results: Methanol extract from F. subbracteata and L. muralis lichens showed relatively high antibacterial activities (p<0.01), whereas aqueous extracts showed no activity against the microorganisms and only acetone extract of L. muralis showed antibacterial activity against the S. epidermidis (MIC=500). Methanol extracts of F. subbracteata and L. muralis had higher antifungal activities than others. Conclusion: The methanol extracts of L. muralis and F. subbracteata showed the highest activity against the bacteria and fungi and it seems that they have some antibacterial and antifungal properties.
Darioush Gharibi, Mohammad Khosravi, Zohreh Hosseini, Fatemeh Boroun, Seyedeh Kolsum Barzgar, Ali Forughi Far,
Volume 3, Issue 1 (1-2015)
Abstract
Introduction: Aloe Vera compounds have inhibitory activity on fungi, bacteria, and viruses. This study examines the antibacterial activity of A. Vera purified extracts including gel, boiled skin, boiled gel, and distilled extract against pathogenic bacteria, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Klebsiella pneumonia and Pseudomonas aeruginosa were elucidated. Method: The bacterial strains were collected from veterinary hospital. Freshly collected A. vera leaves were used for the juice extraction of gel, skin and distilled extracts. Antibacterial effects of various A. Vera extracts were evaluated using broth microdilution method. The crude polysaccharides of boiled skin extract were purified by phenol method; and fractionated by anion exchange chromatography. For each bacterium, minimum inhibitory concentration of various A. Vera extracts was determined. The protein expression changes of treated bacteria were detected by SDS-PAGE electrophoresis. Results: The distillate extract exhibited more antibacterial effects than other extracts. Out of seven-carbohydrate fractions of the skin extract, the fractions 6 and 7 had antibacterial effects on S. aureus and MRSA at 0.089 and 0.134 mg/ml, respectively; also fraction 5 showed antibacterial effects on MRSA at 0.113 mg/ml concentration. The protein profiles of these strains before and after treatment with A. Vera showed significant differences at 175, 60, 200 and 70 kDa protein bands of S. aureus, MRSA, P. aeruginosa and K. pneumonia, respectively. Conclusion: This finding showed that the distillate extract despite the minimal amount of carbohydrate and protein was more efficient against both Gram-positive and Gram negative bacteria.
Marziye Taheri, Moein Saleh, Amir Hesam Nemati, Mehdi Ariana, Esfandiar Shojaei, Masoud Mardani, Mohammad Katouli, Mohammad Pooya,
Volume 4, Issue 3 (7-2016)
Abstract
Introduction: Almost 80% of nosocomial urinary tract infections (UTIs) are due to catheterization. Catheter-associated UTI (CAUTI) is the primary source for colonization of antibiotic-resistant pathogens, and uropathogenic Escherichia coli (UPEC) is the most common causative bacteria. This study was conducted to determine the phylogenetic groups, and antibiotic resistance pattern as the two important features of pathogenicity of UPEC isolates collected from urinary catheters. Methods: The UPEC isolates were obtained from the urinary catheters of the patients without UTI, from two referral hospitals during 2015 to 2016. Phylogenetic grouping was performed using a multiplex PCR. Antibiotic susceptibility and extended spectrum beta-lactamase (ESBL) production were tested by the disc diffusion method. Multidrug resistance was determined based on a recent guideline. The presence of some resistance genes was examined by a PCR assay. Results: Thirty-eight percent of the isolates were UPEC, all of them belonged either to B2 (62.5%) or D (37.5%) phylogenetic groups. The UPEC isolates showed a very high resistance to ciprofloxacin (80%) and the third-generation cephalosporins (72.5%). Seventy percent of the isolates were ESBL-producing, and 90% of them were multiple drug resistant (MDR). Meanwhile, the frequency of the resistance genes: ctxM, aacIV, sul1, shv, and qnrA in the isolates were 95%, 82.5%, 77.5%, 72.5%, and 45%, respectively. Conclusion: High resistance to fluoroquinolones and third-generation cephalosporins, as well as high frequency of ESBL-producing and MDR UPEC isolates, are a great concern. This phenomenon is probably the consequence of the indiscriminate use and on the counter availability of antibiotics, which should be considered in empirical therapy of CAUTIs.
Muhammad Faisal Shahbaz Akram, Muhammad Ashraf, Sultan Ali, Syeda Iqra Kazmi,
Volume 5, Issue 1 (1-2017)
Abstract
Introduction: Probiotics are defined as live non-pathogenic microorganisms and if administered in adequate amounts, can have beneficial effects on their hosts. This study aimed to isolate Gram-positive bacteria from different sources and to evaluate their probiotic properties. Methods: We obtained five samples from various sources including yogurt, infant feces, cheese, and soil under aseptic methods. The samples were inoculated on MRS agar and M17 medium. Biochemical assays identified isolated bacteria. The probiotic effect of isolated bacteria was tested by applying acidic pH 2.0, 0.3% w/v bile salt concentration and gastric juice in the samples. The antibiotic susceptibility profiling and their antimicrobial effects against Escherichia coli, Staphylococcus aureus, Salmonella enterica and Pseudomonas aeruginosa, were determined. Results: Four Gram-positive bacteria including Lactobacillus acidophilus, Bifidobacterium bifidum, Lactococcus lactis and Bacillus subtilis were isolated from yogurt, infant feces, cheese, and soil, respectively. Except for B. subtilis, all the isolated bacteria were catalase-negative and non-motile. The results showed that viable count of L. acidophilus, B. bifidum, and L. lactis was significantly high (P<0.05), and B. subtilis was sensitive. The isolates showed an antimicrobial effect against all indicator pathogens except P. aeruginosa. The isolated B. subtilis showed no antimicrobial effect. The antibiotic susceptibility was determined for ten different antibiotics. All the isolates were susceptible to most of the antibiotics (table 6) and resistant to penicillin G, gentamicin, vancomycin, and kanamycin. Conclusion: The species L. acidophilus, B. bifidum, and L. lactis fulfilled the criteria for probiotic properties and can be used in field conditions as probiotics.
Mohammad Khosravi, Darioush Gharibi, Farnoosh Kaviani, Mehrdad Mohammadidust,
Volume 6, Issue 2 (4-2018)
Abstract
Introduction: Red seaweeds are the source of polyanionic polymers that play a critical role in ionic, mechanical, and osmotic functions of the cells. The Gracilaria polysaccharides have numerous biological activities. This research aimed to compare the in vivo and in vitro effects of the various carbohydrate fractions of the seaweed Gracilariopsis persica. Methods: The crude polysaccharide of the G. persica seaweed was extracted using three methods, including soaking in water, hot water extraction, and acid extraction. On the optimal conditions, the seaweed polysaccharides were extracted using HCl 0.1 M 10% (w/v), and the crude carbohydrates were precipitated by ethanol. The extract was fractionated on diethylaminoethyl cellulose (DEAE-C) column using a NaCl gradient. The antimicrobial activity of each fraction was assessed by microdilution broth method against 6 bacteria species, including Staphylococcus aureus, Escherichia coli, Methicillin-resistant Staphylococcus aureus (MRSA), Salmonella typhimurium, Pseudomonas aeruginosa, and Aeromonas hydrophila. Moreover, the obtained fractions were orally administered (100 µg/day) for 7 days to 10 groups of 4 adult NMRY mice. The effects of various fractions were evaluated based on the bactericidal effect of the sera and some immune response indicators, including complement activity and humoral immune response against sheep red blood cells (SRBC). Results: Most of the fractions had direct antibacterial effects; however, oral administration of the fractions neither increased the antibacterial effect of sera nor triggered the complement activity. However, the fractions 1, 2, 5, and 6 significantly induced the humoral immune response against SRBC. Conclusion: The G. persica seaweed has direct antibacterial effects. However, unlike the humoral immune response induction, the carbohydrate fractions have no effects on innate immune responses.
Mojtaba Moosavian, Mahtab Khoshkholgh Sima, Maryam Haddadzadeh Shoushtari, Mohammad Amin Fazeli Naserabad,
Volume 6, Issue 4 (10-2018)
Abstract
Introduction: Diffusion of antibiotic resistance genes by horizontal gene transfer has led to the fast emergence of multidrug resistance (MDR) among bacteria. Multiple classes of integrons are effective genetic elements which play a significant role in the acquisition and nosocomial dissemination of resistance factors in strains of Gram-negative bacteria, Pseudomonas aeruginosa, and Acinetobacter baumannii. Methods: In this study, 110 sputum samples were collected from hospitalized patients with tract infections. Identification of the isolates was performed by standard biochemical tests. The most frequent Gram-negative isolates were 25 Enterobacteriaceae (62.5%), (9 Enterobacter spp, 11 Citrobacter spp, and 5 Escherichia coli), 6 P. aeruginosa (15%) and 9 Acinetobacter spp (22.5%). Susceptibility of the isolates to antibiotics was carried out by Kirby-Bauer disk diffusion method according to CLSI guidelines, and finally, the class 1 integrons were detected by PCR. Results: Maximum resistance rate among Gram-negative isolates was observed to ceftazidime, co-trimoxazole, and cefotaxime with 89%, 87%, and 82%, respectively. A low-level resistance was recognized for imipenem 32% and gentamicin 34%, while an intermediate level resistance was found against the norfloxacin 40% and ciprofloxacin 44%. Out of 6 P. aeruginosa and 9 A. baumannii isolates, 2 (33.3%) and 3 isolates (33.3%) were positive for class 1 Integrons, respectively, while all Enterobacteriaceae isolates (100%) were negative for class 1 Integrons. Class 1 integrons were detected among of MDR isolates. Conclusion: Our results showed that monitoring MDR isolates and detection of class 1 integrons in these isolates is necessary for promotion of antibacterial stewardship.
Parisa Sabbagh, Azadeh Ferdosi-Shahandashti, Mehdi Rajabnia, Amirhosein Maali, Elaheh Ferdosi Shahandashti,
Volume 8, Issue 1 (1-2020)
Abstract
Introduction: Integronsare are mobile genetic elements which play an essential role in the distribution of antibiotic-resistant genes among bacteria. This study aimed to investigate the Class I integron in Klebsiella pneumoniae clinical isolates and its association with multiple drug resistance (MDR). Methods: We obtained 30 K. pneumoniae isolates from patients admitted to the ICU at Shahid Beheshti Hospital in Babol City, Mazandaran province, Iran. Different classes of antimicrobials were used to determine the resistance pattern. A polymerase chain reaction (PCR) was performed to detect the int1 gene of the class I integrons. We also investigated the suitability of the two pairs of primers for the detection of the intl gene. Results: Antibiotic susceptibility testing revealed 90% resistance to ceftizoxime, cefotaxime, and cefepime, 88.6% to cefazolin, gentamicin, ticarcillin, and ceftriaxone, 83.3% to imipenem, 60% to ciprofloxacin, 56.6% to ofloxacin, and 36.6% to amikacin. The PCRs with two pairs of primers, one designed previously and the other in this study, detected int1 in 36.6% and 60% of samples, respectively. Conclusion: The int1 gene was of high prevalence (60%) in K. pneumoniae isolates. This factor could play a significant role in the spread of MDR strains. Also, failure to adhere to essential points in the design of the primer can lead to the production of primers with low specificity and efficiency, which reduces the proper identification of antibiotic resistance genes.
Narjes Mohammadi Bandari, Hossein Keyvani, Mohammad Abootaleb,
Volume 8, Issue 2 (4-2020)
Abstract
Introduction: The emergence of extended-spectrum β-lactamase (ESBL) and carbapenem-resistant Enterobacteriaceae, especially Klebsiella pneumoniae isolates, has become a severe concern worldwide. This study aimed to determine the prevalence of blaVIM and blaNDM genes among K. pneumoniae isolates. Methods: One hundred-eighty-one K. pneumoniae isolates were obtained from different clinical specimens of patients hospitalized at Firoozgar hospital, Tehran, Iran. The isolates were identified by standard biochemical tests, and their identity was confirmed by Vitek 2 (bioMérieux, France), a fully automated system for bacterial identification. The isolates were subjected to antimicrobial susceptibility testing and screened for ESBL by double-disc synergy test (DDST) and modified Hodge test (MHT) for the detection of carbapenemase. PCR was also used to detect the presence of blaVIM and blaNDM resistance genes in the isolates. Results: The Vitek 2 system confirmed the biochemical test results. The highest and lowest rates of resistance to antibiotics belonged to cefepime (83.9%) and imipenem (55.2%). Eighty-six and 100 isolates showed to produce ESB and KPC by DDST and MHT, respectively. About 71% and 97% of the 100 isolates were positive for blaVIM and blaNDM genes, respectively. Conclusion: The high rate of ESBL- and KPC-producing K. pneumoniae isolates in our hospital setting revealed resistance to conventional antibiotics, which limit our options in choosing appropriate antimicrobials. Although the management of infections associated with these organisms is challenging, it is essential to control such strains to prevent the outbreak.
Mostafa Alamholo,
Volume 8, Issue 4 (10-2020)
Abstract
Introduction: Plant essential oils can be used as alternative agents for the treatment of antibiotic-resistant pathogenic bacteria. This study aimed to investigate the chemical composition, antibacterial, and antioxidant activity of Thymus eriocalyx and Thymus daenensis essential oils against Gram-positive and Gram-negative human pathogenic bacteria. Methods: The aerial part of Thymus eriocalyx and Thymus daenensis in the full flowering stage were collected from West Azerbaijan Province (Urmia), Iran, in 2014. We obtained the essential oils using a Clevenger device. The disc diffusion method was used to determine the antibacterial activity of the essential oils against 15 Gram-positive and Gram-negative PTCC and ATCC bacterial standards. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were measured by microdilution broth method in 96-well plate and free radical scavenging activity by 2,2-diphenyl-1-picrylhydrazyl. Chemical analysis of the essential oils performed out by gas chromatography connected to Mass spectrometry. Results: Eleven (94.06%) and seven (90.76%) compounds were identified in T. eriocalyx and T. daenensis essential oils, respectively. The major components of T. eriocalyx essential oil were thymol (37.8%) and α-terpineol (14.91%), and of T. daenensis were thymol (52.36%) and carvacrol (16.72%). T. eriocalyx essential oil showed the highest activity against B. cereus with MIC of 0.93 μg mL- and MBC of 1.87 μg mL-. The most potent radical scavenging activity was also obtained for T. daenensis essential oil. Conclusion: Essential oil components of T. eriocalyx and T. daenensis may have the potential to be used as antimicrobial agents against antibiotic-resistant pathogenic bacteria.
Shahrbanoo Sadat Sadat, Ania Ahani Azari, Masoumeh Mazandarani,
Volume 8, Issue 4 (10-2020)
Abstract
Introduction: The study aimed to determine the antibacterial activity of ethanolic extract of Matricaria chamomilla (chamomile), Malva sylvestris, and Capsella bursa-pastoris against Methicillin-resistant Staphylococcus aureus (MRSA) isolated from clinical specimens. Methods: The plants were collected from Ziarat Village, southern heights of Gorgan, and the required parts were separated and then thoroughly dried in the shade. After grinding, extraction was performed by the maceration method. The extract was dried at 37°C for 24 h. A concentration of 50 mg/ml of each extract was obtained in 10 ml 5% dimethyl sulfoxide and sterilized. For the antibacterial assay, agar well diffusion and broth microdilution methods were used. Results: Our results showed no inhibitory effect for the ethanolic extracts of M. sylvestris, and C. bursa-pastoris against the MRSA isolates in both antibacterial assay. The chamomile flower extract showed antibacterial activity against the 20 MRSA isolates at 50 and 25 mg/ml concentrations. The extract from chamomile leaves demonstrated an inhibitory effect on the 7 MRSA isolates. The extracts from chamomile flowers demonstrated MIC and MBC at a concentration of 6.25 and 12.5 mg/ml for most MRSA isolates, while these values for the extracts from chamomile leaves were 12.5 and 25 mg/ml for a few MRSA isolates, respectively. Conclusion: In this study, the ethanolic flower extract of chamomile showed significant antibacterial activity against the MRSA isolates. Hence, this extract may be an alternative to antibiotic therapy and a good option to control infections caused by MRSA and pathogenic bacteria.
Fatemeh Shahdadi, Maryam Payandeh, Ali Salehi Sardoei,
Volume 9, Issue 1 (3-2021)
Abstract
Introduction: Dracocephalum polychaetum Bornm and Nepeta cataria L. are two plants from the Lamiaceae family with antibacterial, antifungal, and antiviral properties. This study evaluated the phenolic compounds, antioxidant activity, and effect of aqueous extracts on the survival of Lactobacillus acidophilus and Bifidobacterium animalis in a simulated gastrointestinal environment. Method: The aerial parts of plants were collected at the vegetative growth stage from the Hanza-Kuh's highlands in the Bahr Asman region of Jiroft city, Iran, in spring 2018. The total phenolic content of plants and antioxidant activity were measured using Folin–Ciocalteau and DPPH (2, 2-diphenyl-1-picrylhydrazyl) methods, respectively. For investigating the survival of probiotic bacteria in a simulated gastrointestinal environment, bacterial suspension was inserted into tubes containing 0, 100, 250, 500, and 1000 ppm of extracts and then incubated in a simulated gastrointestinal environment. The probiotic bacteria were counted using an MRS agar medium at various incubation times. Results: The results showed that the amount of total phenolic compounds in the D. polychaetum Bornm extract (44.55 mg/g dry matter) was higher than that of N. cataria L. (18.37 mg/g dry matter). With increased extracts concentrations, the percentage of DPPH-free radicals increased, and D. polychaetum Bornm extract in all concentrations showed higher DPPH free radical inhibitory content compared to the N. cataria L. extract. The viability results in the same gastrointestinal environment showed that samples containing N. cataria extract had a more remarkable survival rate than the controls and D. polychaetum Bornm extract. Conclusion: Using less than 500 ppm of D. polychaetum Bornm and N. cataria L. aqueous extracts can increase probiotic bacteria growth and viability.
Mahboobeh Akbarizare,
Volume 9, Issue 3 (9-2021)
Abstract
Introduction: In many countries, people use animal dung smoke to treat infections. Ancient physicians Avicenna and Zakaria Razi (Zakariyyā Rāzī) recommended these compounds to treat infections. In rural areas of Iran, people used female donkey dung (Anbarnasara) smoke to treat respiratory tract and burn wound infections. This study evaluates the antibacterial and antifungal properties of Anbarnasara smoke. Methods: The smoke from burning Anbarnasara was collected in a 50%-methanol solution. Following evaporation of methanol at 50ºC, the remaining compound was dissolved in DMSO, and various concentrations (3.1-100 mg/ml) were prepared. The antimicrobial effects of various concentrations (3.1-100 mg/ml) of Anbarnasara smoke solution (ASS) were investigated, using the agar well diffusion method on 15 different microorganisms, including eight standard microorganisms and seven bacteria species from clinical specimens. Also, GC-MS analysis was performed to identify the components in ASS. Results: Antifungal activity on Candida albicans was observed at 6.2- 100 mg/ml of ASS. Among Gram-positive and Gram-negative bacteria, the most significant inhibition zones belonged to Staphylococcus epidermidis (30.5± 0.70 mm) and Proteus mirabilis (25± 0.00 mm) at 100 mg/ml. GC-MS analysis showed 16 major peak areas, and of identified components, ~50% were phenolic compounds. Conclusion: Our results confirmed the ancient physicians' belief in the antibacterial and antifungal properties of Anbarnasara smoke.
Shamsi Saad Shamsi, Abdelkader A. Elzen, Khadija M. Ahmad,
Volume 9, Issue 4 (12-2021)
Abstract
Introduction: Burkholderia cepacie complex (Bcc) is an emerging multidrug-resistant gram-negative bacteria frequently isolated from health care facilities worldwide. The present study investigated the prevalence of Bcc in health care settings in Sebha, Libya. Methods: Two hundred swabs were initially collected. Forty-seven nosocomial Bcc isolates were identified from three medical care facilities, i.e., 40 (20%) from Sebha Medical Center, five from the Sebha Infertility Treatment Center, and two from Althanweya Clinic. The isolates were identified using a combination of biochemical tests and USP chapter <60> Microbiological Examination of Non-Sterile Products Tests for Burkholderia Cepacia Complex guidelines. A UPGMA dendrogram was used to examine the biochemical relationship of isolates. Some of the putative virulence factors contributing to the pathogenicity of the isolates were also explored. Results: Of the 47 isolates, 29.79% were B. cepcia, 23.40% B. cenocepcia, 12.77% B. thailandensis, 8.51% B. vietnamiensis, 6.38% B. ambifaria, B. pyrrocinia, and B. stabilis each, 4.26% B. anthina, and 2.13% B. arboris. A variation in virulence factors was observed among isolates; all (100%) isolates produced siderophore, 91% had capsules, 91% produced lipase, 89% formed a biofilm, and 49% produced alkaline protease. The UPGMA dendrogram revealed that Bcc species shared substantial phenotypical identity among themselves. Conclusion: In developing countries with limited resources, diagnostic challenges in identifying Bcc species can be resolved using selective media and USP chapter <60> guidelines.
Mostafa Alamholo,
Volume 10, Issue 1 (3-2022)
Abstract
Introduction: The members of the genus Tanacetum are important medicinal plants. This study investigated the chemical composition and antibacterial activity of Tanacetum lingulatum and Tanacetum polycephalum essential oils on human infectious bacteria. Methods: The aerial part of two plants were collected from Urmia Province, Iran. The essential oils were extracted using a Clevenger device. The antibacterial effect of essential oils was determined using the disc diffusion assay, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) by serial dilution method. Also, free radical scavenging activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) was examined. Chemical composition was measured using the Gas Chromatography-Mass Spectrometry (GCMS). Results: The major constituents in T. polycephalum and T. lingulatum essential oils were 1,8- cineole and camphor, respectively. The highest sensitivity (MIC of 0.312 μg mL- ( was observed with T. polycephalum against Bacillus subtilis. The lowest IC50 (most potent radical scavenging activity) belonged to T. lingulatum essential oil. Pseudomonas aeruginosa and Streptococcus pyogenes showed resistance to T. lingulatum essential oil. Conclusion: The essential oil of T. polycephalum and T. lingulatum are potential natural antibacterials to treat human pathogenic bacteria and can be used as alternatives to produce antimicrobial agents.
Mohammad Hossein Akbari, Ania Ahani Azari, Leila Fozouni,
Volume 10, Issue 1 (3-2022)
Abstract
Introduction: This study aimed to determine the frequency of extended-spectrum beta-lactamases (ESBL) and different drug resistance phenotypes in Enterobacteriaceae isolated from clinical specimens in Gonbad-e Kavus, Golestan Province. Methods: 220 clinical samples of urine, blood, pus, sputum, CSF, body fluids, and ear and eye discharge were collected during six months from April to September 2021 at a referral hospital. The samples were cultured on blood and MacConkey agar and incubated overnight at 37 °C. Standard biochemical tests and the API20E enteric identification system were used to identify bacteria. The Kirby-Bauer disk diffusion method determined the antibiotic resistance pattern, and the phenotypic confirmatory test was used for detecting ESBL producers. Results: 108 Enterobacteriaceae isolates were identified from different clinical specimens out of the samples. The isolates were Escherichia coli (36.1%), Klebsiella pneumonia (25%), Enterobacter cloacae (18.5%), Citrobacter freundii (11.1%) and Proteus mirabilis (9.2%). The highest resistance and susceptibility among the isolates belonged to sulfamethoxazole-trimethoprim (68.5%) and meropenem (11.1%), respectively. The highest prevalence of multidrug-resistant (MDR) and ESBL were observed in E. coli and Proteus mirabilis isolates. Conclusions: In this study, the high frequency of MDR phenotypes in the isolates may suggest an increasing trend of antibiotic resistance in Enterobacteriaceae. This could greatly impact the management and treatment of infections caused by these drug-resistant bacteria. Therefore, infection-control measures and continuous monitoring is recommended for controlling the spread of ESBL-producing strains in different geographical areas.
Elham Sheykhsaran, Hamed Ebrahimzadeh Leylabadlo, Farbod Alinezhad, Hadi Feizi, Hossein Bannazadeh Baghi,
Volume 10, Issue 2 (6-2022)
Abstract
The term "Nosocomial" is attributed to the diseases acquired by the patient under medical care. Various microorganisms, including bacteria, viruses, and fungi, may contribute to developing nosocomial infections (NIs). Urinary tract infections (UTI), surgical-site infections (SSI), bloodstream infections (BSI), and pneumonia are the most well-known instances. We investigated various aspects of NIs and the main causative agents of NIs, particularly bacteria, antibiotic resistance, crucial viral infections in hospitals, and a brief survey of fungal infections. It was concluded that specific human body tissues such as those in the lungs and urinary tract are more likely to be a target for nosocomial pathogens. The fatalities associated with these infections, particularly in the intensive care unit (ICU), are serious concerns, and transmission by health facilities has become a primary medical issue because of its spread into the community. Another medical point is antibiotic resistance which is a leading cause of prolonged periods of hospitalization and makes the treatment procedure harder and costlier. Additionally, measures to prevent the spread of NIs and minimize the economic loss are discussed. All physicians and medical students must be updated about different kinds of these infections, their causative agents, challenges, and how to deal with them to reduce the consequences and improve public health.
Golsuom Sourazur,
Volume 11, Issue 3 (9-2023)
Abstract
Introduction: Bacterial vaginosis (BV) is the most common vaginitis in childbearing women. Despite the availability of various treatments, recurrence rates are high. This study investigated the effects and side effects of vitamin C vaginal tablets in patients with Gardnerella vaginalis infection based on Amsel criteria and the culture. Methods: A double-blind, randomized clinical trial was conducted on 48 non-pregnant women aged 15-40 years referred to Alawi Hospital in Ardabil Province, Iran. After the diagnosis of G. vaginalis infection based on Amsel criteria and culture methods, the patients were randomly assigned to receive either intravaginal 250 mg vitamin C (intervention group, n=24) or 250 mg metronidazole tablets (control group, n=24) for eight nights. The patients were evaluated 10 ± 2 and 30 ± 2 days before and after the treatment. Results: Culture and Amsel criteria showed significant improvement in both groups during the first and fourth weeks of treatment. However, the intervention group that received vitamin C showed a more substantial improvement (P<0.002, P<0.001). Intravaginal vitamin tablets were more effective than metronidazole tablets in treating G. vaginalis infection. Furthermore, vitamin C tablets improved the abnormal growth of vaginal microflora and reduced the abnormally high pH of the vagina. This treatment effectively prevented the recurrence of G. vaginalis infection for one month. Conclusion: Vitamin C vaginal tablets showed to be a promising alternative treatment for G. vaginalis infection, but further research is needed to confirm these findings and address potential limitations.
Musa Y. Tula, Osaretin Iyoha, Richard Elisha, Joel Filgona, Abumhere S. Aziegbemhin,
Volume 11, Issue 3 (9-2023)
Abstract
Introduction: The hospital environment can significantly contribute to the spreading of bacterial isolates that pose a risk to public health. In this study, we analyzed bacteria found on hospital fomites and the hands of healthcare workers to determine the presence of resistant enzymes such as ESBLs and AmpC. Methods: We studied 100 samples collected from hospital fomites - including the hands of healthcare workers - for bacterial growth, which were subsequently identified using standard procedures. Standard disk methods were used to screen Gram-negative bacteria (GNB) for ESBL and AmpC production, including presumptive and confirmatory testing. Results: 46 (46.0%) Gram-negative bacteria were isolated from all sampling sites, including a preponderance of Pseudomonas aeruginosa and Escherichia coli. Of the 46 GNBs, 31 (67.4%) and 27 (58.7%) were resistant to ceftazidime and ceftriaxone, respectively. The double disk synergy test (DDST) showed ESBL in 34 (73.1%) of the isolates, with the highest prevalence in E. coli (32.3%) and P. aeruginosa (26.5%). These isolates were primarily associated with patients’ bedding (32.4%), tablets (26.5%), and sinks (20.6%), although there was no statistical difference (P=0.998). Presumptive AmpC production was 100% in isolates of K. pneumoniae, C. diversus, Shigella spp., and S. marcescens but variable in other isolates. The combined disk test (CDT) showed that 29 (63.0%) isolates were AmpC-producing GNB, with the highest prevalence in E. coli (34.5%). Conclusion: The isolation of bacteria with these types of resistance from the surfaces of hospital fomites may negatively impact the quality of healthcare delivery.
Naik Shraddha Dinkarrao, Ghogare Harish Subhashrao, Kulkarni Smita Sitaram, Mulay Manjushree Vijay,
Volume 11, Issue 4 (12-2023)
Abstract
Introduction: The emergence of carbapenem-resistant Enterobacteriaceae (CRE) poses a significant public health concern due to its potential for increased mortality and morbidity. The limited availability of effective antibiotics further exacerbates the dissemination of carbapenem-resistant bacteria. This study aimed to evaluate the prevalence of carbapenem resistance and carbapenemase production in Enterobacteriaceae isolates using the Modified Hodge Test. Methods: This observational study was conducted at the Department of Microbiology, MGM Medical College & Hospital, Aurangabad, Maharashtra, from November 2015 to November 2017. 171 Enterobacteriaceae isolates from various clinical samples were comprehensively tested for carbapenem resistance and carbapenemase production. This involved the use of carbapenem discs (ertapenem, meropenem, and imipenem), E-test strips for ertapenem and meropenem, and the Modified Hodge Test (MHT) for carbapenemase identification. Results: Among the 171 tested Enterobacteriaceae isolates, a substantial proportion (40%) displayed resistance to carbapenems, as determined by disc diffusion and E-test methods. Among the carbapenem-resistant isolates, 13 were positive for the MHT. Conclusion: Our study revealed a notable prevalence of carbapenem resistance in Enterobacteriaceae isolates from a tertiary care hospital. The MHT, following Clinical and Laboratory Standards Institute (CLSI) guidelines, demonstrated high sensitivity (> 90%) and specificity (> 90%) for detecting KPC-type carbapenemases in these isolates. Treatment options for CRE infections are limited, with tigecycline and colistin identified as potential options. Our study highlights the importance of promptly diagnosing different carbapenemases using PCR techniques. Consequently, we strongly advocate for implementing robust antimicrobial stewardship programs and infection control practices in healthcare settings to prevent CRE spread effectively.
Berina Muhović, Nadia Islam, Murtaza M. Tambuwala, Altijana Hromić-Jahjefendić,
Volume 11, Issue 4 (12-2023)
Abstract
Introduction: The rising foodborne disease outbreaks poses significant challenges to key objectives in food microbiology. This trend is primarily attributed to global population growth and intensified food production. A thorough microbiological assessment of end products is therefore crucial. Methods: We evaluated the bacterial presence and abundance in various dairy products (sour cream, cottage cheese, buttercream, cream cheese, pasteurized milk, protein-rich milk, and yogurt) sourced from a local supermarket in Bosnia and Herzegovina. Two enumeration methods (pour plating and most probable number) were employed alongside morphological, biochemical, and molecular analyses (Gram staining, oxidase test, catalase test, indole test, lipolytic activity assay, and RT-qPCR). Our focus was on spoilage-causing lactic acid bacteria (LAB), hygiene indicator thermotolerant coliforms (TC), and the foodborne pathogen Salmonella spp. Results: Six out of seven dairy products harbored high levels of LAB, suggesting potential spoilage, except for cottage cheese. Additionally, both TC and Escherichia coli exceeded acceptable microbial limits, particularly in pasteurized milk. Furthermore, initial tests detected presumptive Salmonella spp. in cream cheese, protein-rich milk, and yogurt. Conclusion: These results highlight the need for stringent sanitary practices during dairy production to extend product shelf-life and prevent premature spoilage from unwanted bacterial presence. Moreover, eliminating pathogen contamination during manufacturing is crucial to mitigate serious food safety risks, including potential food poisoning.
