Do infected inguinal lymph nodes increase the incidence of postoperative groin wound infection?

Risk factors for postoperative wound infection in patients undergoing vascular surgery may include age, comorbid conditions, wound classification, use of prosthetic grafts, and repeat operations. Groin incisions, in particular, pose substantial risk during placement of prosthetic grafts.

To investigate the role of infected inguinal lymph nodes (LN) in groin wound infection (GWI), we excised an inguinal LN from 69 consecutive patients (89 groins) undergoing 36 infrainguinal reconstructions, 24 aortobifemoral bypasses, 12 extra-anatomic femoral bypasses, 11 vein stripping, and 6 femoral pseudoaneurysm repairs. LN Gram staining was performed, and aerobic and anaerobic cultures were obtained. In addition cultures were taken from any ulcerated or gangrenous lesion on the ipsilateral open extremity lesion.

Bacteria were isolated from 10 of 89 LN (11.2%) and included Staphylococcus species, gram-negative rods, diphtheroids, and Peptostreptococcus. Three of the 10 LN were taken from extremities with open lesions; seven were not. In no case did organisms cultured from a groin LN correlate with its corresponding open extremity lesion. Four GWI developed after operation (4%). In each case results of the groin LN cultures were negative. Three of the GWI were associated with an ulcerated or gangrenous lesion on the ipsilateral extremity (p = 0.08, odds ratio = 7.6), but in only one case did the organisms from the GWI correspond to that in the open lesion. The development of a GWI was strongly associated with insulin-dependent diabetes mellitus (p = 0.009, odds ratio = 22.9).

In conclusion, 11% of groin LN harbored bacteria, but none of these were associated with subsequent development of a wound infection. Instead, insulin-dependent diabetes mellitus and the presence of an open skin lesion on the ipsilateral extremity seemed to be associated with an increased risk of wound infection.