Characteristics of Surgical Site Infection Following Colorectal Surgery in a Tertiary Center

Extended-Spectrum beta-Lactamase-Producing Bacteria Culprits in Disease

Eliana Kalakouti, MD; Constantinos Simillis, MD; Gianluca Pellino, MD; Nabeela Mughal, MD; Oliver Warren, MD; Sarah Mills, MD; Emile Tan, MD; Christos Kontovounisios, MD; Paris P. Tekkis, MD


Wounds. 2018;30(4):108-113. 

In This Article


A total of 123 patients admitted both electively (n = 92) and due to emergency (n = 31) were included in this study. Twenty-nine percent (n = 9) of the emergency admissions and 19% (n = 17) of the elective admissions developed a SSI, averaging to a total of 21% (n = 26) overall for the time period between March 2015 and March 2016 (Figure 1, Figure 2 and Figure 3).

Figure 1.

Incidence of surgical site infection (SSI) after 123 laparotomies/laparoscopies/laporoscopic-assisted operations performed between March 2015 and March 2016.

Figure 2.

Monthly breakdown of overall operations (n = 123). SSI: surgical site infection

Figure 3.

Mode of admission breakdown (emergency versus elective). SSI: surgical site infection.

From the sample of the 26 patients who developed a SSI, the median age was 65 and 65% (n = 17) of the group were white British and 54% (n = 14) were female. Patients with an American Society of Anesthesiologists score between I–II and III-IV were 46% (n = 12) and 54% (n = 14,), respectively. Thirty five percent (n = 8) had hypercholesterolemia, 48% (n = 11) hypertension, and 17% (n = 4) asthma or chronic obstructive pulmonary disease (COPD). No patient was noted to have diabetes mellitus. The average length of stay was 19 days (Table 2).

One hundred percent of the SSIs had a wound culture taken at the time infection was suspected. Thirty-eight percent (n = 10) of the wound infections grew ESBL-producing pathogens and 62% (n = 16) grew non-ESBL microbes (Figure 4). The microorganisms isolated included Enterobacter cloacae, Pseudomonas aeruginosa, Klebsiella pneumoniae, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Morganella morgana, and Proteus mirabilis. The ESBL-producing isolates were identified in 100% (n = 3) of the E cloacae, 25% (n = 1) of the K pneumonia, and 60% (n = 6) of the E coli (Figure 5). The most common ESBL-producing pathogen was E coli.

Figure 4.

Microbiology breakdown (n = 26). ESBL: extended spectrum β-lactamase

Figure 5.

Number of patients for whom each pathogen grew in their wound culture (blue) and the number of those wound cultures which were positive for ESBL (red).ESBL: extended spectrum β-lactamase isolates; MRSA: methicillin-resistant Staphylococcus aureus

On the preoperative MRSA screen, 92% (n = 24) tested negative, 4% (n = 1) positive, and 4% (n = 1) did not receive screening. Seventy-three percent (n = 19) received preoperative screening for resistant gram-negative bacteria, and all had a negative result (Figure 6).

Figure 6.

Preoperative MRSA and resistant gram-negative screen (n = 26).MRSA: methicillin-resistant Staphylococcus aureus

The TVN reviewed 81% (n = 21) post infection, and 54% received negative pressure wound therapy (NPWT) using dedicated dressing as a means of treatment. Negative pressure wound therapy with PICO (Smith & Nephew, London, UK) was applied to 1 patient in the operating room, and the patient still got an infection. Forty-six percent (n = 12) did not receive NPWT.