Correlation between superficial and intra-operative specimens in diabetic foot infections: results of a cross-sectional Tunisian study

Abstract

Objective: To determine the correlation between superficial, and intra-operative specimens in diabetic foot infections (DFIs).Methods: We conducted a cross-sectional study in patients with DFIs hospitalized in a Tunisian teaching hospital. Superficial specimens were collected for all patients, and intra-operative specimens were collected in operated patients. The specimens were processed using standard microbiology techniques. Antimicrobial susceptibility testing was carried out according to the protocol established by the European Committee on Anti-microbial Susceptibility Testing. Intra-operative and superficial specimens were considered correlated if they isolated the same microorganism(s), or if they were both negative.Results: One hundred twelve patients, 81 males and 31 females, mean age 56 years, were included. Superficial samples were positive in 77% of cases, and isolated 126 microorganisms. Among the positive samples, 71% were monomicrobial. The most frequently isolated microorganisms were Enterobacteriaceae (53%), followed by streptococci (21%) and Staphylococcus aureus (17%). Nine microorganisms (7%) were multi-drug resistant. Intra-operative samples were positive in 93% of cases. Superficial specimens were correlated to intra-operative specimens in 67% of cases. Initial antibiotic therapy was appropriate in 70% of cases. The lower-extremity amputation and the mortality rates were 41% and 1%, respectively.Conclusion: In our study, DFIs were most frequently caused by Enterobacteriaceae and superficial specimens were correlated to intra-operative specimens in only two thirds of cases. Clinicians should emphasize on the systematic practice of intraoperative specimens in all patients with DFIs treated surgically, while well-performed superficial specimens could be useful for prescribing appropriate antibiotic therapy in other patients.Keywords: Diabetic foot infections, superficial specimens, intra-operative specimens.

Diabetic foot ulcer disease in African continent: ‘From clinical care to implementation’ – Review of diabetic foot in last 60 years – 1960 to 2020

“…However, the complete epidemiology and microbiology of foot infections in this population need to be better defined and characterized. Patients with DFUs in SSA mostly present to health facilities with sepsis and gangrene already established, resulting in significant mortality if rapid action is not taken [1][2][3][160][161][162][163][164][165][166][167][168][169][170][171][172][173]. Diabetic foot infection can present with cellulitis (the least invasive), deep soft tissue infection (involving fascia, muscles and deep tissue) or osteomyelitis which generally underlies chronic foot ulcers, developing through the contiguous spread of soft tissue infection in an ulcer to the underlying bone [1][2][3][160][161][162][163][164][165][166][167][168][169][170][171][172][173].…”

Antibiotic Stewardship in the Management of Infected Diabetic Foot Ulcer Disease in Less Developed Countries

“…Recent Turkish literature [ 17 ], and articles from the Southern Mediterranean [ 17 , 22 , 23 ], Asia [ 24 ] and (Sub)‐Saharan Africa [ 25 , 26 , 27 , 28 , 29 , 30 ], indicate a high prevalence of P. aeruginosa , for which the reasons remain unknow. Several African studies from specialised diabetes centres and hospitals report a >60% resistance to third generation cephalosporins and an increasing resistance towards carbapenems among both, the Gram‐negative and Gram‐positive bacteria [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ], whereas in Asia, the microorganisms classified as MDR seem to shift towards more Gram‐negative bacteria [ 17 ]. Unsurprisingly, MDRs in DFI might contribute to a worse clinical prognosis when compared to their susceptible bacterial counterparts [ 17 , 23 , 24 , 25 , 26 ].…”

Methicillin-Resistant Staphylococcus aureus from Diabetic Foot Infections in a Tunisian Hospital with the First Detection of MSSA CC398-t571

“…In our study, the prevalence of S. aureus detected in DFIs was 21.9%. Three previous retrospective studies from different Tunisian hospitals showed that S. aureus was isolated in 9%, 17% and 31% of DFIs [ 8 , 9 , 15 ]. This variation in percentages might be due to a difference in the geographical areas, the method applied to obtain cultural samples and study periods, especially the case of our study which took place during the COVID-19 pandemic and partly explaining the decrease in the number of consulting patients.…”

“…Diabetic foot infection (DFI), defined as soft tissue or bone infection below the malleoli, is the most common diabetic complication that often leads to hospitalization and non-traumatic lower extremity amputation [ 4 , 5 , 6 ]. Many studies have shown that DFI is polymicrobial [ 7 , 8 , 9 ]. Particularly, S. aureus is the bacteria implicated the most [ 10 ].…”

“…These studies were limited to the bacteriological profile of DFI patients and showed controversial results. Enterobacteriaceae were the main bacteria causing the infection in diabetics in two of them [ 8 , 9 ], while S. aureus was the most frequent pathogen isolated in the remaining one [ 15 ]. Thus, there are currently no data on the molecular characterization of the bacterial strains involved, risk factors or treatment of multi-drug resistance organisms in patients with DFI in Tunisia.…”