Open Journal of Medical Microbiology

Journal Information
ISSN / EISSN : 2165-3372 / 2165-3380
Current Publisher: Scientific Research Publishing, Inc. (10.4236)
Former Publisher: Scientific Research Publishing, Inc. (10.4236)
Total articles ≅ 212
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Latest articles in this journal

Kaniz Fatema, Shahina Sultana, Mohammad Hedayet Ali, Tanzina Akter, Khadiza-Tul- Kobra, Shiful Islam
Open Journal of Medical Microbiology, Volume 11, pp 58-67; doi:10.4236/ojmm.2021.111005

Object: To isolate and identify the microorganisms from the burn patients admitted to the National Institute of Burn and Plastic Surgery Unit in Tertiary Medical College Hospital, Bangladesh. A total number of fifty wound surface swab samples of first and second-degree burn patients were collected and the microbial analysis as well as the study of antibacterial susceptibility was conducted. The study showed the bacterial isolates were found. 45 (90%) of wound swab were positive among 50 and only 5 samples (10%) were negative in bacterial growth, which presented invasive burn wound infection from both sex age groups marked 12 - 60 years. The total viable count TVC-11651 CFU/plate was found and the highest amount in the second-degree burn patients. The results showed that Pseudomonas aeruginosa was common in all positive samples 6636 CFU/plate (57%) followed by Staphylococcus aureus 4070 CFU/plate (35%), Klebsiella spp. 450 CFU/plate (5%), Proteus spp. 243 CFU/plate (2%), and E. coli 162 CFU/plate (1%). Most of the pathogens were found to be drug-resistant while several isolates were noted to be multi-drug resistant. The growth of multidrug-resistant organisms should be considered as a serious risk factor in a burn unit. Aggressive infection control measures should be applied to limit the emergence and spread of multidrug-resistant pathogens.
Akosua Bonsu Karikari, Courage Kosi Setsoafia Saba, Stephen Wilson Kpordze
Open Journal of Medical Microbiology, Volume 11, pp 18-31; doi:10.4236/ojmm.2021.111002

Thermophilic Campylobacters are zoonotic bacteria which are universally famous for causing enteritis in humans. They are normally found as commensals in the digestive tract of food animals with poultry being a major reservoir of the pathogenic species. This study highlighted the presence of Campylobacter in poultry (commercial and domestic) and humans (patients and asymptomatic individuals) and characterized strains by biotyping and susceptibility test in the Northern region of Ghana where animal husbandry is commonly practiced but zoonotic studies are limited. A total of 1087 specimens from stools of humans and cloacal swabs of poultry were screened from 25th October, 2017 to 7th May, 2019. Samples were cultured on modified charcoal-cefoperazone-deoxycholate agar and isolates identified using standard microbiological procedures and Lior Biotyping, while the antibiogram of isolates was determined by the Kirby-Bauer disk diffusion method. The frequency of Campylobacter was 43.1% and 12.9% respectively in poultry and humans. Campylobacter jejuni were recovered from 84% of commercial birds and 64% of domestic birds and in humans significantly fewer strains were observed in patients than asymptomatic individuals (p 0.05). Biotype distribution revealed C. jejuni biotype I prevalence in domestic birds, patients and asymptomatic individuals whereas Bioytype II was largely found in commercial poultry. All isolated strains of Campylobacter were resistant to tetracycline and 69.4% of Campylobacter jejuni strains were resistant to erythromycin. Imipenem and the aminoglycosides were relatively effective as resistance of 10% and below 20% were respectively obtained. None of the endorsed treatment drugs (erythromycin, ciprofloxacin, and tetracycline) can be admitted in this region due to common resistance found among strains against these agents.
Danait Andemichael Solomon, Andrew K. Nyerere, Alice Kanyua, Caroline Wangari Ngugi
Open Journal of Medical Microbiology, Volume 11, pp 32-46; doi:10.4236/ojmm.2021.111003

The upsurge of candidemia in the past years has been an immense encumbrance on public health and the number of deaths caused by candidemia particularly in critical care unit patients is devastating. Candida species harbor a 30% - 60% mortality rate and compared to stable people or those with less serious illnesses, this ranges from 60% to 80% of those who are chronically ill patients. Grounded on a recent report from a tertiary care hospital in Kenya showing the emergence of previously unobserved species: Candida auris, this study aimed to determine the prevalence, species distribution, and antifungal susceptibility profile of candidemia in critical care unit patients of the hospital. 378 Critical Care Unit patients were enrolled for the study from January 2019 to January 2020. Positive archived isolates were sub-cultured using Saboraud Dextrose Agar. Candida species were identified utilizing API20C AUX and Vitek-2. Antifungal susceptibility testing was conducted using the Liofilchem MIC Test strip. Out of 378 patients, thirty-one presented a positive culture for Candida species. The prevalence of Candidemia was 8.2% with 9 (29.03%) Candida auris, 8 (25.81%) Candida albicans, 6 (19.35%) Candida parapsilosis, 3 (9.68%) Candida famata, 3 (9.68%) Candida tropicalis, 1 (3.23%) Candida duobushaemolumonii, and 1 (3.23%) Candida lusitaniae. A resistance pattern to Fluconazole was observed among Candida auris and Candida parapsilosis, and resistance to Flucytosine was observed in Candida tropicalis, whereas susceptible MIC values were obtained for the other drugs. There is an increase in candidemia among critical care unit patients in the health facility posing a public health challenge. Moreover, the onset of new species Candida auris which is unprecedented in Kenya warrants enhanced infection control, and the uniform resistance of Candida auris, Candida parapsilosis, and Candida tropicalis towards Fluconazole and Flucytosine necessitate constant drug monitoring for empirical treatment regime. In contrast, the high potency of Echinocandins and Amphotericin-B demonstrate them as the drug of choice.
Mesut Akil, Ahmet Ozkeklikci, Eylem Akdur Ozturk, Aygul Sadiqova, Nuray Altintas, Selda Karamil, Ozge Sarica Yilmaz, Aysegul Unver, Nazmiye Altintas
Open Journal of Medical Microbiology, Volume 11, pp 69-79; doi:10.4236/ojmm.2021.112006

Objective: To evaluate three different serological tests [Indirect Hemaglutination (IHA), Enzyme Linked Immunosorbent Assay (ELISA) and Western Blotting (WB)] using native crude antigen for diagnosis of hepatic cystic echinococcosis (HCE) patients. Materials and Methods: Sheep hydatid fluid (HF) was collected from fertile cysts obtained from a slaughterhouse and used as an antigen. Forty patients who were attended the Dr. Ersin Arslan Training and Research Hospital in Gaziantep, Turkey, were investigated. Serum samples were obtained from surgically confirmed CE patients. Healthy Turkish people and 16 patients with other helminthic infections were included as a control group. Results: Of the 40 analyzed patients, 10 (25%) were men and 30 (75%) were female. The average age was 46.97 years (s.d.; 18.95). The majority of the patients had a single cystic lesion situated in one lobe of the liver (usually in the right lobe) (55%), 32.5% of patients had two cystic lesions and 12.5% of patients had multiple cyst formations with various numbers. In all cases, ultrasound (US) examinations were positive and the size of cysts was between 2.1 - 12.7 cm. Twenty-three patients of the total 40 patients were classified according to the WHO classification system based on US findings. According to the results of WB analysis, molecular weights of 8 kDa (80%), 12 kDa (80%), 22 - 24 kDa (97.5%), 26 kDa (97.5%), 34 kDa (100%), 36 - 38 kDa (90%), 45 - 50 - 55 kDa (97.5%), and 60 - 75 kDa (97.5%) bands were identified. But 34, 50, and 55 kDa bands were also found in other helminthic diseases. Conclusion: The specificity and sensitivity of three serological tests (IHA, ELISA and WB) using crude antigen were compared by diagnosing hepatic cystic echinococcosis patients. IHA and ELISA showed high sensitivity but low specificity. Western blotting showed low sensitivity but high specificity.
L. H. Nkasa, K. J. Kadinekene, O. Kiabanzawoko, B. Tchey, S. Kimbonza, M. O. Lunguya, S. S. Karhemere Bin, M. C. Mulenga, T. J. J. Muyembe, S. J. Kayembe, et al.
Open Journal of Medical Microbiology, Volume 11, pp 47-57; doi:10.4236/ojmm.2021.111004

The present study reports the in vivo anti-Mycobacterial Activity of a Phytomedicine “MATHESIA” on Mycobacterium ulcerans. It also explores the influence of ethanolamine (alkali agent) on the in vivo activity of some antibiotics (Isoniazid, Rifampicin, Ethambutol) used in the treatment of Buruli ulcers in DR Congo. Experiments were conducted on adult white Wistar rats of both sexes with the weights comprising between 110 - 165 g. The result obtained have shown that the phytomedicine MATHESIA (pH 10) has a good in vivo activity on M. ulcerans and the duration for wounds healing and total cicatrization was 6 days; whereas this duration was 10, 12, 14, and 16 days respectively for Rifampicin (IV, pH 10), Kibadi’s solution (X, pH 10), Ethambutol (VIII, pH 10) and Isoniazid (VI, pH 10). The result also showed that the use of the ethanolamine as alkali compounded in the treatment of wounds due to Buruli ulcer along with other antibiotics reduced considerably the duration of complete healing comparatively to their solutions at pH bellow or equal to 7.
Timothy S. Horseman, Michael B. Lustik, Keith S. K. Fong
Open Journal of Medical Microbiology, Volume 11, pp 1-17; doi:10.4236/ojmm.2021.111001

Background: Early detection and accurate identification of foodborne pathogen outbreaks is an important public health function. Increased clinical adoption of multiplex PCR assays or culture independent diagnostic tests (CIDT) correlates to more stool specimens sent to public health laboratories (PHL) for characterization. Isolation and confirmation of enteric bacterial pathogens can prove difficult to consistently recover. The purpose of this study was to evaluate the performance of a broad-use laboratory developed enrichment broth for isolation of Campylobacter, Salmonella, Shigella, and Yersinia strains from stool specimens. Methods: The study compared differences in positivity rates among media and enrichment combinations at specific time points. Comparison of direct inoculation (DI), enrichment using a lab-developed Enteric Bacterial Enrichment (EBE) broth and gold-standard isolation methods were conducted to test current utility of this established practice with stool specimens heat injured and non-injured. Results: A total of 234 spiked stool samples, 175 non-injured and 59 heat injured, were tested with varying bacterial concentrations. For non-injured stools, direct inoculation performed better for Campylobacter and Yersinia than enrichment. Conversely, Salmonella and Shigella recovery and limit of detection increased with enrichment. Campylobacter had the highest percent recovery while Shigella being the lowest from direct plating at 6-hour and 24-hour enrichment periods. Among broths, EBE performed the best for Yersinia and similar to Selenite broth for Salmonella and Shigella. Generally, heat injured stool had a significantly lower percent of recovery than non-heat injured with a higher limit of detection across organisms. Conclusion: Our data suggest there is an only utility for targeted enrichment of CIDT positive Salmonella stool specimens. We highlight the difficulties of formulating an enrichment broth capable of supporting a variety of enteric pathogens with standardized incubation. Increasing demands on PHL infrastructure warrant further examination of enhancing organism isolation and cost analyses for CIDT positive specimens.
Akira Okamoto, Saki Otsuji, Miho Kamako, Ikumi Inoue, Kokoro Tasaka, Juntaro Kato
Open Journal of Medical Microbiology, Volume 10, pp 139-152; doi:10.4236/ojmm.2020.103012

Chlorhexidine is a widely used antiseptic agent; however, its bactericidal effect against bacterial endospores is limited. The genus Bacillus is spore-forming gram-positive bacteria that are ubiquitously found in the environment and cause opportunistic infection and food poisoning. The susceptibility of bacterial endospores to chlorhexidine was previously evaluated in Bacillus subtilis, but the primary target for disinfection with antiseptic agents, including chlorhexidine, should be harmful strains. We aimed to evaluate the susceptibility of harmful cereus group including Bacillus cereus, and to compare that with harmless Bacillus species, containing B. subtilis. We evaluated the susceptibility of the 15 strains of the cereus group to chlorhexidine in comparison with the 5 other strains, named the subtilis group in this study. Our results indicated that chlorhexidine exerted a bacteriostatic effect against Bacillus species at practical concentrations, especially during long-term exposure. The strains of B. cereus group in this study displayed relatively lower susceptibility to the antiseptic than the B. subtilis group according to the minimum inhibitory and bactericidal concentrations. We concluded that there are intrinsic differences in the susceptibility to chlorhexidine between the groups, but the molecular mechanisms are unknown. The minimum inhibitory or bactericidal concentrations of disinfectants other than chlorhexidine may also need to be clarified in the B. cereus and B. subtilis groups.
Josephat Tonui, Marianne Mureithi, Walter Jaoko, Christine Bii
Open Journal of Medical Microbiology, Volume 10, pp 190-203; doi:10.4236/ojmm.2020.104017

Background: Fungal infections represent a significant cause of morbidity and mortality among immunocompromised individuals. Pulmonary fungal infection may be missed or misdiagnosed as tuberculosis (TB) hence complicating management of these patients. The current study reports the spectrum of filamentous fungi isolated from sputum of TB relapse and retreatment cases at selected reference facilities in Kenya. Methods: A total of 340 sputum samples collected during the period of June 2018 to June 2019 were subjected to mycological investigations. The samples were mucolysed and inoculated on sabourauds dextrose agar (SDA) and incubated at 30°C for 7 days and checked daily for fungal growth. Moulds were identified by macroscopic and microscopic morphological features and the species were confirmed by sequencing. Results: The diversity of fungi out of the 340 sputum samples analyzed was as follows; 16% (n = 53) were positive for moulds with Aspergillus species being the predominant constituting 68 % (n = 36). Among the Aspergilli, A. flavus and A. niger were the most frequently isolated adding up to 23%, (n = 12) and 15% (n = 8) respectively. Additionally, Paecillomyces variotii (9%, n = 5), Scedosporium aspiospermum (6%, n = 3), Mucor racemosus (8%, n = 4) and Penicillium spp. (9%, n = 5) were also recovered. Conclusion: The isolated fungi represented potential respiratory pathogens that could be responsible for persistent TB like symptoms despite treatment that could be misdiagnosed as relapse requiring treatment. Fungal investigation of all presumptive TB relapse cases should be advocated before treatment. This will reduce unnecessary retreatment, delayed antifungal intervention and unwarranted morbidity and mortality associated with misdiagnosis.
Justin Nyasinga, Geoffrey Omuse, Njenga John, Andrew Nyerere, Shima Abdulgader, Mae Newton, Andrew Whitelaw, Gunturu Revathi
Open Journal of Medical Microbiology, Volume 10, pp 204-221; doi:10.4236/ojmm.2020.104018

Staphylococcus aureus has maintained its clinical relevance as a major cause of hospital and community acquired infections globally with a high burden of antimicrobial resistance (AMR). Though reported, the burden of infection, antimicrobial resistance and molecular epidemiology of S. aureus are not well defined in Kenya. This descriptive review evaluated reported data on the detection and characterization of S. aureus infections in Kenya. Published data between 2000 and 2020 were evaluated. S. aureus isolation frequencies varied from 1% in blood specimens to 52.6% among skin and soft tissues infections while MRSA rates ranged from 1% to 84.1%. While penicillin resistance has consistently been high, last line and recent antibiotics such as vancomycin, linezolid, teicoplanin and daptomycin have retained their efficacy. Data on MRSA carriage in the community, among HCWs and inpatients is limited. Global clones (CC1, CC5, CC8, CC22, CC30, CC45 and CC239) alongside a few novel MRSA strains have been reported with staphylococcal protein A (spa) sequence based clustering yielding four major clusters (spa CC359, spa CC005, spa CC121 and spa CC021) in circulation. MRSA strain ST239/241 (t037) seems predominant in the country. Despite a clear paucity of data, the present analysis points to a high infection and AMR burden in S. aureus with global MRSA clones in circulation. Standardized national surveillance and reporting incorporating molecular tools for identification and characterization will help fill existing gaps in the understanding of the evolving epidemiology of MRSA infections.
S. Fakoya, K. T. Adegbehingbe, I. S. Ademakinwa
Open Journal of Medical Microbiology, Volume 10, pp 58-70; doi:10.4236/ojmm.2020.102006

Pleurotus ostreatus was obtained from the wild and evaluated for its antibacterial and antioxidant activities. The antibacterial activities of the methanolic and aqueous extracts against clinical isolates of Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli with vancomycine and amicosin as positive control against the isolates were examined using agar well diffusion assay and the zones of inhibition for the methanolic extract varied for different organisms as zones of inhibition were highly pronounced in Escherichia coli having 18.0 ± 1.41 mm followed by Klebsiella pneumoniae of 17.0 ± 0.58 mm then Staphylococcus aureus of 14.0 ± 1.53 mm and finally Pseudomonas aeruginosa 13.0 ± 0.58 mm. While for the aqueous extract, no inhibition was observed in three isolates apart from Pseudomonas aeruginosa in which the zone of inhibition was just 8.0 ± 1.00 mm. The total antioxidant activity of aqueous Pleurotus ostreatus differed significantly with total phenolic of 12.55 ± 0.11 mg GAE/g, total flavonoid of 7.22 ± 1.60 mg QE/g, ABTS of 1.99 ± 0.06 mmol TEAC/100g, FRAP of mean value of 5.25 ± 0.25 mg/g and also Pleurotus ostreatus was able to scavenged DPPH in a dose-dependent manner of 0 - 13.3 mg/ml. The inhibitory effect of Pleurotus ostreatus can therefore be attributed to the presence of phenolic and flavonoid compounds in the extract. Also, the result of the ABTS+ scavenging ability of Pleurotus ostreatus as trolox equivalent antioxidant capacity (TEAC) revealed that the extracts of Pleurotus ostreatus has ABTS scavenging ability. The FRAP mean value shows the ability of Pleurotus ostreatus extract to reduced Iron (III) to Iron (II) indicates its redox potential which presents the mushroom a good antioxidant source, suitable for health benefits when consumed.
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