Distribution of Causative Microorganisms in Diabetic Foot Infections: A Ten-Year Retrospective Study in a Tertiary Care Hospital in Central Malaysia

Abstract

Diabetes mellitus is a global pandemic, especially in Southeast Asia. Diabetic foot infection (DFI) is a common complication of this condition and causes significant morbidity and mortality in those affected. There is a lack of locally published data on the types of microorganisms and empirical antibiotics being prescribed. This paper highlights the importance of local microorganism culture and antibiotic prescription trends among diabetic foot patients in a tertiary care hospital in central Malaysia. This is a retrospective, cross-sectional study of data taken from January 2010 to December 2019 among 434 patients admitted with diabetic foot infections (DFIs) using the Wagner classification. Patients between the ages of 58 and 68 years old had the highest rate of infection. Pseudomonas Aeruginosa, Proteus spp., and Proteus mirabilis appeared to be the most isolated Gram-negative microorganisms, and Staphylococcus aureus, Streptococcus agalactiae, and MRSA appeared to be the most common Gram-positive microorganisms. The most common empirical antibiotics prescribed were ampicillin/sulbactam, followed by ciprofloxacin and ceftazidime, and the most common therapeutic antibiotics prescribed were ampicillin/sulbactam, ciprofloxacin, and cefuroxime. This study could be immensely pertinent in facilitating future empirical therapy guidelines for treating diabetic foot infections.

Microbiology and Antimicrobial Resistance in Diabetic Foot Infections

“…This system plays a crucial role in regulating various aspects, including biofilm formation and the expression of virulence factors such as toxins and degradative exoenzymes. Clinically, a study conducted at a central Malaysian tertiary care hospital indicated that Staphylococcus spp infections are associated with major amputations [45]. In a similar manner, DFU patients infected with Enterococci exhibited a significantly higher in-hospital amputation rate (72%) compared to those with non-Enterococci infections (50%) [27].…”

“…Most common Gram-negative bacteria include Pseudomonas aeruginosa, Escherichia coli, Klebsiella species, and Proteus species. Their prevalence differs according to geographical region [45][46][47].…”

“…In complicated diabetes mellitus where DFU are more prevalent, polymicrobial infections are more common than mono-bacterial ones [45,71,103]. Polymicrobial infections can include bacterial and non-bacterial agents such as fungi or viruses, with bacteria being the most dominant infections [104].…”

“…In a study conducted at a tertiary hospital in central Malaysia, P. aeruginosa emerged as the primary contributor to amputations, and notably, a majority of amputee patients were male [45]. The severity of infections caused by this opportunistic pathogen was closely linked to the specific strain of Pseudomonas and its antibiotic sensitivity.…”

“…While Escherichia coli is not commonly associated with DFIs, surprisingly it was identified as the fourth most frequent Gram-negative bacterium in DFIs in central Malaysia. All E. coli infections resulted in major amputations, underscoring E. coli's aggressive capacity to infiltrate deep tissues, including bones, leading to osteomyelitis [45]. E. coli encompasses multiple strains, each exhibiting variations in virulence and antibiotic sensitivity.…”