Bacterial isolation and antibiotic susceptibility from diabetic foot ulcers in Kenya using microbiological tests and comparison with RT-PCR in detection of S. aureus and MRSA

ABSTRACT Diabetic foot ulcer (DFU) is a major complication of diabetes with high morbidity and mortality rates. The pathogenesis of DFUs is governed by a complex milieu of environmental and host factors. The empirical treatment is initially based on wound severity since culturing and profiling the antibiotic sensitivity of wound-associated microbes is time-consuming. Hence, a thorough and rapid analysis of the microbial landscape is a major requirement toward devising evidence-based interventions. Toward this, 122 wound (100 diabetic and 22 nondiabetic) samples were sampled for their bacterial community structure using both culture-based and next-generation 16S rRNA-based metagenomics approach. Both the approaches showed that the Gram-negative microbes were more abundant in the wound microbiome. The core microbiome consisted of bacterial genera, including Alcaligenes, Pseudomonas, Burkholderia, and Corynebacterium in decreasing order of average relative abundance. Despite the heterogenous nature and extensive sharing of microbes, an inherent community structure was apparent, as revealed by a cluster analysis based on Euclidean distances. Facultative anaerobes (26.5%) were predominant in Wagner grade 5, while strict anaerobes were abundant in Wagner grade 1 (26%). A nonmetric dimensional scaling analysis could not clearly discriminate samples based on HbA1c levels. Sequencing approach revealed the presence of major culturable species even in samples with no bacterial growth in culture-based approach. Our study indicates that (i) the composition of core microbial community varies with wound severity, (ii) polymicrobial species distribution is individual specific, and (iii) antibiotic susceptibility varies with individuals. Our study suggests the need to evolve better-personalized care for better wound management therapies. IMPORTANCE Chronic nonhealing diabetic foot ulcers (DFUs) are a serious complication of diabetes and are further exacerbated by bacterial colonization. The microbial burden in the wound of each individual displays diverse morphological and physiological characteristics with unique patterns of host-pathogen interactions, antibiotic resistance, and virulence. Treatment involves empirical decisions until definitive results on the causative wound pathogens and their antibiotic susceptibility profiles are available. Hence, there is a need for rapid and accurate detection of these polymicrobial communities for effective wound management. Deciphering microbial communities will aid clinicians to tailor their treatment specifically to the microbes prevalent in the DFU at the time of assessment. This may reduce DFUs associated morbidity and mortality while impeding the rise of multidrug-resistant microbes.

Download Full-text

The Profile of Microbiological Pathogens in Diabetic Foot Ulcers

Frontiers in Medicine ◽

10.3389/fmed.2021.656467 ◽

2021 ◽

Vol 8 ◽

Author(s):

Wei Chai ◽

Yuqing Wang ◽

Huancheng Zheng ◽

Song Yue ◽

Yan Liu ◽

...

Keyword(s):

Diabetic Foot ◽

Antibiotic Susceptibility ◽

Susceptibility Testing ◽

Limb Amputation ◽

Foot Ulcers ◽

Diabetic Foot Ulcers ◽

Antibiotic Resistant ◽

Resistant Strains ◽

Pathogen Spectrum ◽

Main Complication

Diabetic foot, a main complication of diabetes mellitus, renders the foot susceptible to infection, and may eventually lead to non-traumatic limb amputation due to the deterioration of diabetic foot ulcers (DFUs). Characterizing the pathogen spectrum and antibiotic susceptibility is critical for the effective treatment of DFUs. In the current study, the characteristics and antibiotic susceptibility of the pathogen spectrum were analyzed. Secretions from the DFUs of 102 patients were cultured, and dominant pathogens were identified by using test cards. Antibiotic susceptibility of dominant pathogens was assayed by the Kirby–Bauer assay. We found that the dominant pathogens varied with age, duration of diabetes, blood sugar control, and the initial cause of ulcers. Moreover, the dominant pathogens were susceptible to at least one antibiotic. However, the antibacterial efficacy of several commonly used antibiotics decreased from 2016 to 2019. Our study indicates that the identification of dominant pathogens and antibiotic susceptibility testing is essential for the treatment of DFUs with effective antibiotics, while the abuse of antibiotics should be strictly restrained to reduce the generation of antibiotic-resistant strains.

Download Full-text

Bacteriological Profile and their Antibiotic Susceptibility Pattern in Diabetic Foot Ulcers in a Tertiary Care Hospital, Puducherry, India

International Journal of Current Microbiology and Applied Sciences ◽

10.20546/ijcmas.2017.603.179 ◽

2017 ◽

Vol 6 (3) ◽

pp. 1560-1566

Author(s):

K. Manasa Saraswathy ◽

S. Pramodhini , C.P. Ganesh Babu ◽

S. Umadevi K.S. Seetha

Keyword(s):

Diabetic Foot ◽

Antibiotic Susceptibility ◽

Tertiary Care Hospital ◽

Tertiary Care ◽

Foot Ulcers ◽

Care Hospital ◽

Diabetic Foot Ulcers ◽

Susceptibility Pattern ◽

Antibiotic Susceptibility Pattern ◽

Bacteriological Profile

Download Full-text

Frequency of Most Prevalent Bacteria in Wound of Diabetic Foot Ulcers and their Antimicrobial Susceptibility to Antibiotics

10.53350/pjmhs211592223 ◽

2021 ◽

Vol 15 (9) ◽

pp. 2223-2225

Author(s):

Ashfaq Nasir ◽

Muhammad Najam Iqbal ◽

Ghulam Hassan ◽

Muhammad Arshad Abbas ◽

Hafiz Jawad Abdul Raheem ◽

...

Keyword(s):

Emergency Department ◽

Antimicrobial Susceptibility ◽

Diabetic Foot ◽

Antibiotic Susceptibility ◽

Foot Ulcer ◽

Diabetic Foot Ulcer ◽

Foot Ulcers ◽

Diabetic Patients ◽

Diabetic Foot Ulcers ◽

Cross Sectional

Background: Most of the diabetic patients present as diabetic foot in surgical outdoor and emergency department. Diabetic Foot infections are common and take long duration to be treated. Both Gram positive and Gram negative aerobic bacteria are involved in diabetic foot infection. Aim: To determine the frequency of most prevalent bacteria in wound of diabetic foot ulcers and to determine the antimicrobial susceptibility of isolated bacteria from diabetic foot ulcers so that an empirical antibiotics can be started before the report of culture and sensitivity. Methods: This cross sectional study was conducted in surgical unit 1 of Bahawal Victoria Hospital (BVH) Bahawalpur from 01-08-2020 to 31-07-2021. This study was conducted on 145 patients with diabetic foot ulcer from outdoor and emergency department of BVH. Data about patient’s demography, duration of diabetes, duration of DFUs, type of pathogen and its antibiotic susceptibility was entered on a proforma. Pus sample was obtained from wound under aseptic measures. Culture sensitivity to assess presence of type of pathogen and its antibiotic susceptibility of all the samples was done from the pathology department of the hospital. Results: The mean age of patients was 52.02±10.14 years. There were 77(53.1%) males and 68(46.9%) females. The foot ulcer’s mean duration was 3.81±1.43 months. There were 15(10.3%) patients with St. aureus, 12(8.3%) with E.coli, 12(8.3%) with Proteus mirabilis, 15(10.3%) with P. aeruginosa, 12(8.3%) with Enterobacter spp., 9(6.2%) with Morganella spp., 19(13.1%) with P. vulgaris, 18(12.4%) with P. Mirabilis, 16(11%) with K. pneumonia and 17(11.75) with Morganella pathogen in this study. There were 74(51%) patients sensitive to Amikacin, 73(50.3%) sensitive to Amoxicillin, 66(45.5%) sensitive to Aztreonam, 74(51%) sensitive to Ceftriaxone, 75(51.7%) sensitive to Cefuroxime and 68(49.6%) sensitive to Cephazolin. Conclusion: The most frequent organisms in DFUs, regardless of age, gender and comorbidity, were P. vulgaris, St. aureus and P. aeruginosa. The most sensitive antibiotic in these ulcers was Piperacillin and Meropenem and the most resistant was Cephazolin. Keywords: Diabetic Foot Ulcers, Antimicrobial Susceptibility, St. aureus, P. vulgaris, P. aeruginosa, Piperacillin

Download Full-text