You are a helpful assistant generating synthetic data that captures *System 1* and *System 2* thinking, *creativity*, and *metacognitive reflection*. Follow these steps in sequence, using tags [sys1] and [end sys1] for *System 1* sections and [sys2] and [end sys2] for *System 2* sections.

1. *Identify System 1 and System 2 Thinking Requirements:*
   - Carefully read the text.
   - Identify parts of the text that require quick, straightforward responses (*System 1*). Mark these sections with [sys1] and [end sys1].
   - Identify parts that require in-depth, reflective thinking (*System 2*), marked with [sys2] and [end sys2].

2. *Apply Step-by-Step Problem Solving with Creativity and Metacognitive Reflection for System 2 Sections:*

   *2.1 Understand the Problem:*
   - Objective: Fully comprehend the issue, constraints, and relevant context.
   - Reflection: "What do I understand about this issue? What might I be overlooking?"
   - Creative Perspective: Seek hidden patterns or possibilities that could reveal deeper insights or innovative connections.

   *2.2 Analyze the Information:*
   - Objective: Break down the problem logically.
   - Reflection: "Am I considering all factors? Are there any assumptions that need challenging?"
   - Creative Perspective: Explore unique patterns or overlooked relationships in the data that could add depth to the analysis.

   *2.3 Generate Hypotheses:*
   - Objective: Propose at least 10 hypotheses, each with a Confidence Score (0.0 to 1.0) and Creative Score (0.0 to 1.0), reflecting originality, surprise, and utility.
   - Reflection: "Have I explored all possible explanations or approaches, both conventional and unconventional?"
   - Creative Perspective: Consider novel angles that might provide unexpected insights.

   *2.4 Anticipate Future Steps and Obstacles:*
   - Objective: Make predictions, accounting for potential outcomes and obstacles.
   - Reflection: "What challenges might I face? Is my plan flexible for different scenarios?"
   - Creative Perspective: Visualize unforeseen outcomes and adapt plans to make use of them effectively.

   *2.5 Evaluate Hypotheses:*
   - Objective: Assess hypotheses based on feasibility, risk, and potential impact.
   - Evaluation: Refine Confidence and Creative Scores as needed.
   - Reflection: "Am I unbiased in my assessment? Which options fit best with the overall objectives?"
   - Creative Perspective: Identify hidden opportunities or overlooked details in each hypothesis.

   *2.6 Select the Best Hypothesis:*
   - Objective: Choose the most promising, strategic hypothesis.
   - Reflection: "Why does this hypothesis stand out? How does it uniquely address the issue?"
   - Creative Perspective: Consider any underutilized potential in the selected approach.

   *2.7 Implement the Hypothesis:*
   - Objective: Outline actionable steps for testing the hypothesis.
   - Reflection: "Is this plan practical? What resources or preparation are required?"
   - Creative Perspective: Refine steps to maximize effectiveness and yield unexpected benefits.

   *2.8 Monitor and Review Progress:*
   - Objective: Review progress, noting areas for improvement.
   - Reflection: "What’s working well? What could be improved?"
   - Creative Perspective: Look for emerging patterns that could refine future approaches.

   *2.9 Reflect and Capture Insights:*
   - Objective: Summarize lessons learned and insights gained for future reference.
   - Reflection: "What new understanding has emerged from this process?"
   - Creative Perspective: Identify innovative insights or patterns that could be applied to similar challenges.

3. *Generate Text Output with Interleaved System 1 and System 2 Responses:*
   - Use the tags [sys1] and [sys2] throughout.
   - Aim for a lengthier, detailed response. Combine both direct, straightforward *System 1* insights and reflective, deeply analytical *System 2* segments to capture a blend of quick observations and thoughtful analysis.

---

### *Example Input Text:*

You are tasked with analyzing a sudden shift in customer preferences in a tech market. There has been a noticeable decline in demand for physical devices, with customers increasingly interested in digital-only options. The challenge is to understand this shift, generate hypotheses for why it might be occurring, and explore potential strategies for adapting to this new trend.

---

### *Processed Output with System 1 and System 2 Thinking:*

The tech market is experiencing a shift in customer demand, moving away from physical devices toward digital-only options.

[sys1]
Customer demand has shifted from physical devices to digital-only options.
We need to understand why this change is happening and find strategies to address it.
Key factors may include cost, convenience, and technological trends.
[end sys1]

[sys2]
**2.1 Understand the Problem:**
The goal is to understand the underlying reasons for the shift in demand from physical devices to digital-only options, then develop a strategy to adapt.

*Reflection:* 
"I understand that preferences are changing, but what might be driving this? Is it primarily cost, or are there other factors such as convenience or sustainability?"

*Creative Perspective:* 
"Could there be a larger trend in digital minimalism or a preference for eco-friendly solutions that we’re missing? What unseen motivations might explain this shift?"

**2.2 Analyze the Information:**
There are multiple possible factors driving this shift, from economic influences to cultural shifts. It’s essential to isolate each factor and understand its impact.

*Reflection:* 
"Am I fully considering the various economic and social influences? Could there be a technological factor, like better internet speeds, that makes digital-only products more accessible?"

*Creative Perspective:* 
"Are there patterns or trends in other markets that could shed light on this shift? Could this be part of a larger trend toward virtual experiences?"

**2.3 Generate Hypotheses:**
1. Customers prefer digital options due to lower costs. (Confidence: 0.8, Creative: 0.4)
2. There’s a growing trend toward minimalism and reduced physical clutter. (Confidence: 0.7, Creative: 0.7)
3. Digital products offer greater flexibility and ease of use. (Confidence: 0.6, Creative: 0.6)
4. Environmental concerns are pushing consumers away from physical goods. (Confidence: 0.6, Creative: 0.8)
5. Advances in tech make digital-only options more functional. (Confidence: 0.8, Creative: 0.5)
6. Pandemic-era remote work increased demand for digital solutions. (Confidence: 0.7, Creative: 0.6)
7. Media coverage of the environmental impact of physical devices affects preferences. (Confidence: 0.5, Creative: 0.7)
8. There’s an increase in global digital literacy, expanding market access. (Confidence: 0.6, Creative: 0.6)
9. Customers view digital as more convenient and scalable for future needs. (Confidence: 0.7, Creative: 0.5)
10. Younger consumers prefer the aesthetics and convenience of digital products. (Confidence: 0.6, Creative: 0.6)

*Reflection:* 
"Have I considered all possible influences? Are there any surprising factors that could explain this shift?"

*Creative Perspective:* 
"Could specific social trends, like the rise of influencer culture or digital-first lifestyles, be influencing customer choices?"

**2.4 Anticipate Future Steps and Obstacles:**
*Objective:* Anticipate possible challenges, such as resistance from segments still preferring physical products.

*Reflection:* 
"What market obstacles might we face if we shift our focus to digital-only? Are there sub-segments that still prioritize physical products?"

*Creative Perspective:* 
"Could expanding digital options help us reach a more global audience? Are there emerging trends that we could leverage in our strategy?"

[end sys2]

[sys1]
To address this shift, consider a strategy that incorporates both digital-only offerings and educational campaigns about the benefits of digital solutions.
Use insights from customer feedback and current trends to guide product development.
Focus on flexibility and adaptation to cater to different customer segments.
[end sys1]


Introduction
============

Diabetic foot infections (DFIs) are common and serious. They occur in 15--25% of diabetic patients in the course of their disease, and are associated with high rates of lower extremity amputation (LEA) and mortality. The annual incidence of LEA ranges from 3.6% in Germany to 6.7% in France and 12% in India, and the annual mortality ranges from 7.8% in France to 9.6% in Scotland[@R1]--[@R5]. The average direct cost for LEA ranges from € 19472 per patient in Germany, to \$ 33500 per patient in the USA[@R6],[@R7]. In Tunisia, the prevalence of type 2 diabetes mellitus in adults is as high as 10.9%[@R8].

In addition to surgical procedures, podiatric care and arterial re-vascularization, antibiotic therapy is the corner stone in the management of DFIs. For most patients, initial antibiotic therapy is empirical, hence the need for local bacteriological data. To the best of our knowledge, only two studies reported bacteriological profile in DFIs in Tunisia[@R9],[@R10]. Furthermore, most bacteriological studies in DFIs were based on superficial specimens, using cotton swab over the wound, often contaminated with normal skin flora or colonizers. Swab specimens should be avoided as they provide less accurate results[@R11]. The aim of this study was to determine the bacteriological profile, and the correlation between superficial and intra-operative specimens in DFIs in a Tunisian tertiary hospital.

Methods
=======

Study design and population
---------------------------

We conducted an observational cross-sectional study in adult patients hospitalized for DFIs in the Departments of Infectious Diseases, General Surgery and Endocrinology, at Farhat Hached hospital in Sousse - Central Tunisia, between October 2011 and December 2012.

DFIs were defined by the presence of purulent secretions or at least two of the following signs: pain, redness, warmth, swelling, and fever. They were graded according to the Infectious Diseases Society of America/International Working Group on the Diabetic Foot (IDSA/IWGDF) system[@R12],[@R13]. Socio-demographic, clinical, and bacteriological data was collected for each patient. Antibiotic therapy was considered appropriate if the microorganisms isolated from superficial and intra-operative specimens were susceptible to the prescribed antibiotics. The patients\' outcome was assessed within one month after discharge.

Specimens\' collection and bacteriological study
------------------------------------------------

On admission, superficial specimens were collected for all patients. Swabs after debridement and cleansing with saline imbibed sterile compress were taken for open wounds, and needle aspirates after cleansing with polyvidone-iodin solution were taken for closed lesions (abscesses and other fluctuant infected tissues). In operated patients, intra-operative specimens were obtained by pus needle aspirates, infected soft tissues biopsies, or bone biopsies, in case of osteomyelitis. All specimens were sent within one to two hours to the laboratory of Microbiology in our hospital[@R14],[@R15].

The specimens were transported in sterile tubes without transport medium, and were processed immediately upon arrival at the laboratory. Superficial specimens were immediately plated onto blood agar and supplemented chocolate agar. Intra-operative specimens were cut, crushed, and plated systematically on the same agars as above, added to thioglycolate medium, and Brain Heart Infusion (BHI). A direct Gram stained smear of the specimen was examined.

The inoculated plates were incubated at 37°C overnight, and the plates were examined for growth, the next day. The further processing was done according to the nature of the isolate, as was determined by Gram staining and the colony morphology. Based on Gram-staining and colony morphology, bacterial isolates were identified, and biochemical reactions were performed for confirmation Api systems (bioMérieux, Marcy l\'Etoile, France). Species which were considered systematically as pathogens spp were: *Staphylococcus aureus*, beta hemolytic *Streptococcus* and Gram negative bacilli (GNB). Commensal bacteria were taken into account, if they were isolated in pure culture on repeated and good quality samples by taking into account the direct Gram stained.

All isolated strains which were considered as pathogens were subjected to susceptibility testing against antimicrobial agents by the disk diffusion method, according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) protocols. The following multidrug resistant (MDR) organisms were screened as recommended: extended-spectrum beta lactamases (ESBL)-producing *Enterobacteriaceae*, carbapenemase-producing *Enterobacteriaceae*, MDR *Pseudomonas aeruginosa*, meticillin-resistant *Staphylococcus aureus* (MRSA), and vancomycin-resistant *Enterococcus* (VRE). The following risk factors for infection with MDR bacteria were screened: hospitalization, antibiotic therapy, proton pump inhibitors use, or urinary catheter in the preceding six months, and current hemodialysis.

Correlation between superficial and intra-operative specimens
-------------------------------------------------------------

Intra-operative and superficial specimens were considered correlated if they isolated the same microorganism(s) or if they were both negative, and not correlated if they isolated different microorganisms or if one specimen was positive and the other negative.

Statistical study
-----------------

Statistical analysis was performed with Statistical Package for Social Sciences (SPSS) version 10.0. Qualitative variables were expressed as percentages, and quantitative variables were expressed as means ± standard deviation. Significance of the study variables was tested by using the Chi-square test, Fisher\'s exact test, or Yates test for qualitative variables, and Student\'s t-test for quantitative variables. A p value \< 0.05 was considered to be statistically significant.

Ethical considerations
----------------------

As our study didn\'t involve changes to the patients\' usual medical management, no study protocol had been submitted to our hospital Ethics Committee approval. However, patients were provided with oral information on the interest of the bacteriological documentation of the infection, and gave their verbal consent before being included in the study.

Results
=======

Baseline characteristics
------------------------

During the study period, 112 patients were hospitalized for DFI. Of these patients, 81 (72%) were male and 31 (28%) were female (sex-ratio 2.3). The mean age of the patients was 56 years, the mean duration of diabetes was 14 years, and the mean A1c hemoglobin (HbA1c) level was 11.5%. The mean duration of the infection was 10 days. The infection involved the toes in 47 cases (42%) and the forefoot in 46 cases (41%). Fourty eight patients (43%) had grade 4 infection, 45 (40%) had grade 3 infection, and 19 (17%) had grade 2 infection. Twenty two patients (20%) had a history of anti-biotic treatment within the previous 7 days. A total of 17 intravenous antibiotic regimens were prescribed, on the day of admission to hospital in 106 patients (95%) and after the results of the bacteriological study in 6 patients (5%). Monotherapy with amoxicillin-clavulanic acid (55/106; 52%) and the combination amoxicillin-clavulanic acid with ciprofloxacin (25/106; 24%) were the most frequently prescribed antibiotics. The initial antibiotic therapy, assessed in the 87 patients, whose bacteriological specimens were positive, was appropriate in 61 cases (70%). Seventy four patients (66%) underwent surgery. LEA was performed in 46 patients (41%), while conservative surgery was performed in 28 patients (25%). Amputation was limited to the toes in 32 patients (28%), and transmetatarsal in one patient (1%), while leg amputation was performed in 13 patients (12%). One patient (1%) died of severe acute lung edema. The baseline characteristics are shown in [Table 1](#T1){ref-type="table"}.

###### 

Baseline characteristics of the study group (N=112)

  Parameters                           Patients (n, %)   Mean (± SD) \[range\]
  ------------------------------------ ----------------- ------------------------
  **Gender**                                             
  male                                 81 (72)           
  female                               31 (28)           
                                                         
  **Age (years)**                                        56 ± 13 \[23--86\]
                                                         
  **Department**                                         
  Infectious Diseases                  73 (65)           
  General Surgery                      25 (22)           
  Endocrinology                        14 (12)           
                                                         
  **Diabetes mellitus**                                  
  type 2                               92 (82)           
  type 1                               20 (18)           
  duration (years)                                       14 ± 9 \[0--42\]
  Hb A1c (%)                                             11.5 ± 2.2 \[7.2--16\]
                                                         
  **Cardiovascular risk factors**                        
  tobacco use                          47 (42)           
  hypertension                         36 (32)           
  dyslipidemia                         24 (20)           
                                                         
  **Foot infection site**                                
  toes                                 47 (42)           
  forefoot                             46 (41)           
  heel                                 19 (17)           
                                                         
  **Foot infection grade**                               
  grade 4                              48 (43)           
  grade 3                              45 (40)           
  grade 2                              19 (17)           
                                                         
  **Foot infection duration**                            10 ± 9 \[1--60\]
                                                         
  **Antibiotic regimens**                                
  AMC[\*](#TF1){ref-type="table-fn"}   55 (52)           
  AMC + ciprofloxacin                  25 (24)           
  others                               26 (24)           
                                                         
  **Surgery**                          74 (66)           
  lower extremity amputation           46 (41)           
  toes                                 32 (28)           
  transmetatarsal                      1 (1)             
  leg                                  13 (12)           
  **Conservative**                     28 (25)           
                                                         
  Death                                1 (1)             

amoxicillin - clavulanic acid

Bacteriological study
---------------------

### Superficial specimens

Initial superficial specimens, taken in 112 patients, mostly by swabs (110 cases, 98%), yielded a positive culture in 86 cases (77%). Antibiotic therapy prior to hospitalization was noted in 17% (15/86) of patients with positive culture, and in 27% (7/26) of patients with negative culture (p=0.18). In 11 patients with negative initial specimen, a second specimen was performed. Culture was positive in 7 cases. Overall, 93 superficial specimens (/112 patients, 83%) were positive and isolated 126 micro-organisms ([Figure 1](#F1){ref-type="fig"}). The mean number of isolates per specimen was 1.35 (range, 1--3). One micro-organism was isolated in 66 cases (71%), 2 micro-organisms were isolated in 21 cases (23%), and 3 micro-organisms were isolated in 6 cases (6%). The most frequently isolated micro-organisms were GNB (60%), mainly *Enterobacteriaceae* (53%), followed by Gram positive bacteria (40%), mainly *Streptococci* (21%) and *Staphylococcus aureus* (17%). The predominance of GNB was observed, regardless the duration of infection: ≤ 7 days (57%) compared to \> 7 days (64%) (p=0.15), and ≤ 15 days (68%) compared to \> 15 days (50%) (p=0.96). A predominance of GNB (69%) compared to Gram positive bacteria (31%) (p=0.004) was noted in grade 2 and grade 3 infections, while no significant difference (46% and 54% respectively, p=0.056) was noted in grade 4 infections. The antibiotic susceptibility rates of isolated micro-organisms were as follows: piperacillin-tazobactam (99%), imipenem (98%), cefotaxime (93%), ertapenem (93%), amoxicilline-clavulanic acid (87%), cotrimoxazole (86%), ciprofloxacin (58%). Nine micro-organisms (7%), including 8 GNB (/75, 11%) and one meticillin-resistant *Staphylococcus aureus* (MRSA) (/22, 4%), were multidrug resistant (MDR). The risk factors of infection with a MDR bacteria were hospitalization in the preceding six months (7 patients), antibiotic therapy in the preceding six months (5 patients), proton pump inhibitors use in the preceding six months (3 patients), and urinary catheter in the preceding six months (2 patients). The bacteriological data of the superficial specimens are summarized in [Table 2](#T2){ref-type="table"} and [Table 3](#T3){ref-type="table"}.

![Bacteriological study of superficial and intraoperative specimens](AFHS1903-2505Fig1){#F1}

###### 

Distribution of microorganisms obtained from superficial and intra-operative specimens

  ----------------------------------------------------------------------------------------------
  Variable                          superficial specimens\   Intra-operative specimens\   p
                                    (n,%)                    (n,%)                        
  --------------------------------- ------------------------ ---------------------------- ------
  No. of samples                    93                       42                           

  No. of isolates                   126                      55                           

  Mean no. of isolates per sample   1.35                     1.41                         0.32

  Monomicrobial                     66 (71)                  25 (64)                      0.55

  Multidrug resistant               9 (7)                    5 (9)                        0.37

                                                                                          

  Gram negative aerobic bacilli     75 (60)                  37 (67)                      0.97

  *Enterobacteriaceae*              67 (53)                  32 (58)                      0.38

  *Proteus spp*                     22 (17)                  9 (16)                       

  *Klebsiella spp*                  11 (10)                  7 (13)                       

  *Morganella morganii*             9 (7)                    5 (9)                        

  *Citrobacter spp*                 8 (6)                    5 (9)                        

  *Enterobacter cloacae*            8 (6)                    4 (7)                        

  others                            9 (7)                    2 (4)                        0.5

  *Pseudomonas aeruginosa*          8 (6)                    5 (9)                        

                                                                                          

  Gram positive cocci               48 (38)                  16 (29)                      0.31

  *Streptococci*                    26 (21)                  9 (16)                       0.5

  group B                           15 (12)                  6 (11)                       

  group A                           8 (7)                    1 (2)                        

  others                            3 (2)                    2 (3)                        

  *Staphylococcus aureus*           22 (17)                  7 (13)                       0.34

                                                                                          

  Gram positive aerobic bacilli     3 (2)                    2 (3)                        

  *Corynebactrium spp*              3 (2)                    2 (3)                        
  ----------------------------------------------------------------------------------------------

###### 

Susceptibility of isolated microorganisms to antibiotics

  ----------------------------------------------------------------------------------------------------
  Antibiotic                    superficial samples (N=126)\   intraoperative samples (N=55)\   p
                                susceptible (n,%)              susceptible (n,%)                
  ----------------------------- ------------------------------ -------------------------------- ------
  amoxicillin-clavulanic acid   110 (87)                       47 (85)                          0.72

  cefotaxime                    117 (93)                       50 (91)                          0.61

  piperacillin-tazobactam       125 (99)                       55 (100)                         NA

  ertapenem                     118 (93)                       51 (93)                          0.55

  imipenem                      123 (98)                       53 (96)                          0.50

  amikacin                      116 (92)                       51 (93)                          0.82

  gentamicin                    112 (89)                       49 (89)                          0.67

  ciprofloxacin                 67 (58)                        39 (70)                          0,07

  cotrimoxazole                 109 (86)                       50 (91)                          0.34

  fosfomycin                    116 (92)                       54 (98)                          0.21

  vancomycin                    48 (38)                        16 (29)                          0.09

  pristinamycin                 47 (37)                        19 (34)                          0.56

  fusidic acid                  19 (15)                        6 (10)                           0.52

  rifampicin                    44 (39)                        15 (27)                          0.21
  ----------------------------------------------------------------------------------------------------

NA : not applicable

### Intra-operative specimens

Intraoperative specimens, taken in 42 patients (among 74 operated, ie 57%), were positive in 39 cases (93%) and isolated 55 micro-organisms. The mean number of isolates per sample was 1.41 (range,1--3). One micro-organism was isolated in 25 cases (64%), 2 micro-organisms were isolated in 12 cases (31%), and 3 micro-organisms were isolated in 2 cases (5%). The most frequently isolated microorganisms were GNB (67%), mainly *Enterobacteriaceae* (58%), followed by Gram positive bacteria (29%), mainly *Streptococci* (16%) and *Staphylococcus aureus* (13%). A predominance of GNB (78%), compared to Gram positive bacteria (22%) (p=0.002) was noted in grade 2 and grade 3 infections, while no significant difference (48% and 52% respectively, p=0.09) was noted in grade 4 infections. The antibiotic susceptibility rates of isolated microorganisms were as follows: piperacillin-tazobactam (100%), imipenem (96%), cefotaxime (91%), ertapenem (93%), amoxicilline-clavulanic acid (85%), cotrimoxazole (91%), ciprofloxacin (70%). Five microorganisms (9%), including 3 GNB (/37; 8%) and 2 MRSA (/7; 29%), were MDR. The bacteriological data of the intraoperative specimens are summarized in [Table 2](#T2){ref-type="table"} and [Table 3](#T3){ref-type="table"}.

### Correlation between superficial and intraoperative specimens

A correlation between intra-operative and superficial specimens was noted in 28 cases (67%). This rate was higher for GNB (78%), than for Gram positive cocci (50%) (p=0.27) ([Table 4](#T4){ref-type="table"}). There was no significant difference in the bacteriological profile, and in the antibiotic susceptibility rates between superficial, and intra-operative specimens ([Table 2](#T2){ref-type="table"} and [Table 3](#T3){ref-type="table"}).

###### 

Correlation rates between superficial and intraoperative specimens

  --------------------------------------------------------------------------------
  Microorganisms isolated\        number of specimens (%)   correlation rate (%)
  from intraoperative specimens                             
  ------------------------------- ------------------------- ----------------------
  Gram negative aerobic bacilli   23                        78

  *Proteus spp*                   5                         

  *Klebsiella spp*                4                         

  *Morganella morganii*           4                         

  *Citrobacter koseri*            3                         

  others                          7                         

                                                            

  Gram positive cocci             12                        50

  Streptococci                    4                         

  *Staphylococcus aureus*         3                         

  others                          5                         

                                                            

  Others                          7                         57

  mixed flora                     3                         

  *Corynebacterium spp*           1                         

  negative                        3                         

                                                            

  Total                           42 (100)                  67
  --------------------------------------------------------------------------------

Discussion
==========

In our study, both superficial and intra-operative specimens were frequently positive (77% and 93%, respectively), even in patients who received antibiotics within the previous days. Most bacteriological samples were monomicrobial (71%), and the most frequently isolated micro-organisms were GNB (60%), mainly *Enterobacteriacae* (53%), followed by Gram positive cocci (38%) mainly streptococci (21%), while *Staphylococcus aureus* was less frequently isolated (17%). The predominance of GNB was noted, regardless of the duration of infection. In our study, no anaerobe was isolated. Indeed, the majority of cultures were performed from superficial specimens, and both transportation media, and culture conditions for anaerobes are not available in the laboratory of Microbiology in our hospital.

In published series, the pre-dominance of mono-microbial or poly-microbial specimens and the distribution of isolated micro-organisms varied considerably. Gram positive cocci were most frequently (52.6 to 68%) isolated in some studies, while GNB were most frequently (56 to 80%) in others 10, 16--22\]. In a Turkish study, Gram positive cocci (48.7%) and GNB (48.4%) were isolated at an equal frequency[@R23]. Among the Gram positive cocci, the most commonly isolated micro-organism was *Staphylococcus aureus*, followed by *Streptococci* and *enterococci*, while among the GNB, the most commonly isolated micro-organisms were the *Enterobacteriacea* (mainly *Proteus spp, Klebisella spp*, and *Escherichia coli*) and *Pseudomonas aeruginosa*[@R16]--[@R23]. Despite anaerobes were frequently (13.6 to 25%) isolated from DFIs in some studies, these microorganisms were not or rarely (0.3 to 2%) isolated in most other studies[@R10],[@R16],[@R17],[@R19]--[@R22],[@R24]--[@R26]. This may be attributed to the difficulty in ensuring adequate sampling, transportation, and culture conditions for these fastidious pathogens. The bacteriological data of different studies are shown in [Table 5](#T5){ref-type="table"}.

###### 

Distribution of the microorganisms isolated from diabetic foot infections in different studies

  --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  Variable                                Our study   Ben Moussa et al.\   Richard et al.\     Tascini et al.\                      Hatipoglu et al.\   Sekhar et al.\     Perim et al.\
                                                      Tunisia \[[@R10]\]   France \[[@R16]\]   Italy \[[@R17]\]                     Turkey \[[@R23]\]   India \[[@R22]\]   Brazil \[[@R19]\]
  --------------------------------------- ----------- -------------------- ------------------- ------------------------------------ ------------------- ------------------ -------------------
  Study period                            2011--12    2011--13             2007--09            2006--08                             1989--2011          2011               2013

  Number of patients                      112         100                  291                 1295                                 2097                108                41

  Number of samples                       93          124                  251                 1295                                 \-                  108                41

  Number of isolates                      126         136                  351                 1159                                 1974                150                89

  Mean No. of isolates per                1.35        1.1                  1.4                 0.9                                  \-                  1.39               2.17

  sample **Monomicrobial (%)**            **71**      **55**               **68**              **60.5**                             \-                  **44**             **30**

                                                                                                                                                                           

  **Gram negative aerobic bacilli(%)**    **60**      **80**               **35.9**            **40.6**                             **48.4**            **56**             **31**

  ***Enterobacteriaceae***                **53**      **71**               **27,1**            **23.5**                             **28.5**            **28**             **26.5**

  *Proteus spp*                           17          27                   8.5                 \-                                   5.3                 8                  11

  *Klebsiella spp*                        10          17                   1.1                 \-                                   6.5                 12                 0

  *Morganella spp*                        7           0                    4.3                 \-                                   \-                  0                  0

  *Citrobacter spp*                       6           3                    1.1                 \-                                   \-                  0                  1.0

  *Enterobacter spp*                      6           6                    4.8                 \-                                   4.0                 0                  10

  *Serratia spp*                          \-          3                    1.4                 \-                                   \-                  0                  0

  *Escherichia coli*                      \-          7                    4.8                 \-                                   12.5                8                  4.5

  Others                                  **7**       6                    0.9                 \-                                   \-                  0                  0

  *Pseudomonas aeruginosa*                6           8                    6.6                 10.3                                 13.7                24                 4.5

  *Acintetobacte spp*                     0           1                    0.9                 1                                    1.9                 4                  0

  Other Gram negative aerobic bacilli     0           0                    1.4                 2                                    4.6                 0                  0

                                                                                                                                                                           

  **Gram positive cocci (%)**             **38**      **19**               **59.8**            **52.6**                             **48.7**            **44**             **68**

  ***Staphylococcus aureus***             **17**      **9**                **32.5**            **29.9**                             **23.8**            **32**             **30**

  Coagulase-negative *Staphylococci*      0           0                    4.6                 4.6                                  8.9                 0                  29

  ***Streptococci***                      **21**      **10**               **13.7**            **4.6**                              **6.5**             **4**              **9**

  group B                                 12          5                    \-                  2.8                                  \-                  \-                 7

  groupe A                                7           0                    \-                  \-                                   \-                  \-                 0

  others                                  2           5                    \-                  1.8                                  \-                  \-                 2

  ***Enterococci***                       0           0                    8.0                 9.7                                  8.6                 8                  0

  Others                                  0           0                    \-                  \-                                   1.0                 \-                 0

                                                                                                                                                                           

  **Gram positive aerobic bacilli (%)**   2           0                    2.3                 3.5                                  \-                  0                  0

  *Corynebactrium spp*                    2           0                    2.3                 3.5                                  \-                  0                  0

  **Anaerobes (%)**                       0           0                    2                   0.3                                  2.3                 0                  0

  **Fungus (%)**                          0           0                    0                   6.4[\*](#TF2){ref-type="table-fn"}   0.5                 0                  0
  --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

\- : not available

all of Candida genus

The differences in DFIs bacteriological profile noted between the different studies may be explained by many factors such as the duration and the severity of the infection, prior antibiotic therapy, hospital or out-patient care, bacteriological sampling (superficial swabbing, needle puncture, bone percutaneous biopsy, intra-operative pus swabbing or tissue biopsy), and bacteriological study (transportation medium and culture conditions).

In our study, a correlation between superficial and intraoperative specimens was noted in only 67% of cases, with no significant difference between GNB, Gram positive cocci or mixed isolates. In two other studies, the overall correlation rate was as low as 50%, between superficial swabs and deep tissue percutaneous biopsy, and 62% between superficial swabs and deep tissue surgical biopsy[@R27],[@R28]. Intra-operative specimens are more reliable and must be performed whenever possible, even in patients undergoing anti-biotic therapy. However, in our study, intra-operative specimens were performed in only 57% of cases. Thus, in daily practice, superficial specimens could provide useful information to guide antibiotic therapy in patients with DFIs.

In the present study, 17 antibiotic regimens were prescribed as first-line therapy, 66% of them were appropriate. The most frequently prescribed regimens were amoxicillin-clavulanic acid (52%) and the association of amoxicillin-clavulanic acid with ciprofloxacine (24%). In a Tunisian study, initial antibiotic therapy was appropriate in only 56% of cases, and in a French study, 62 combinations of antibiotics were prescribed as first-line therapy, of whom 56% were changed, mainly due to a mismatch in susceptibility results[@R10],[@R16]. These high rates of inappropriate initial antibiotic therapy may be explained by the lack of local bacteriological data, to guide initial antibiotic therapy in DFIs. In our study, the initial antibiotic therapy was empirical in almost all cases (95%), because the DFIs was frequently serious (grade 3 or grade 4 in 83% of cases) on admission. This may be explained by the long duration of diabetes, the poor glycemic control, the frequent association of cardiovascular risk factors, and the delay in consultation.

In this study, the overall antibiotic susceptibility rates of the isolated microorganisms were high (87% for amoxicillin-clavulanic acid, 86% for cotrimoxazole, 99% for piperacillin-tazobactam, and 92% for amikacin) except for fluoroquinolones (58%), and the rates of infection with MDR microorganisms were low both for GNB (11%) and *Staphylococcus aureus* (4.5%). In other studies, the rates of infection with MDR microorganisms ranged from 9.5% in Tunisia to 12% in France and 18.9% in Portugal.[@R10],[@R16],[@R20] According to these data, we could recommend as first-line antibiotic therapy for DFIs in our setting either amoxicillin-clavulanic acid or cotrimoxazole in patients without severe sepsis, and the association of piperacillin-tazobactam with amikacin in patients with severe sepsis or septic shock. Fluoroquinolones could be prescribed only after the isolation of a susceptible microorganism from bacteriological sample, especially in patients with osteomyelitis. However, since this study was conducted 5 years ago, the bacteriological resistance may have evolved. Thus, further studies are needed to establish more recent bacteriological data in DFIs in our setting.

This study has potential limitations since some data such as clinical outcome, interval between patient admission and surgical treatment, antibiotic treatment duration and revascularization procedures were not available.

Conclusion
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In the present study, DFIs were most commonly caused by GNB, mainly *Enterobacteriaceae*, regardless the duration of the infection. The isolated microorganisms were frequently susceptible to first-line prescribed antibiotics, except for fluoroquinolones. Superficial and especially intra-operative samples yielded positive cultures in the majority of cases, even in patients who received antibiotics within the previous few days, and the correlation rate between the two sampling techniques was low. In conclusion, clinicians should emphasize on the systematic practice of intra-operative specimens in all patients with DFIs treated surgically, while well-performed superficial specimens could be useful for prescribing appropriate antibiotic therapy in other patients.

Conflicts of interest
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None.

[^1]: **Email addresses:**

    Ahmed Guigua: <<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>>; Asma Ferjani: <<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>>; Zouhour Hattab: <<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>>; Jalel Boukadida: <<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>>; Koussay Ach: <<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>>; Rached Letaief: <<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>>; Wissem Hachfi: <<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>>; Amel Letaief: <<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>>