Cryptic Bacteria of Lower Limb Deep Tissues as a Possible Cause of Inflammatory and Necrotic Changes in Ischemia, Venous Stasis and Varices, and Lymphedema.

Background: Infections and inflammation of the lower limb skin, soft tissues, and vessels are more common than in other body regions. The aim was to determine whether cryptic bacteria dwelling in deep tissues are the cause.

Methods: We performed bacteriologic studies of specimens harvested from arteries of amputated ischemic legs, leg varices, and tissue fluid/lymph and lymphatics in lymphedema.

Results: Calf arteries contained isolates in 61% and femoral arteries in 36%, whereas normal cadaveric organ donors' arteries in 11%. Bacterial deoxyribonucleic acid (DNA) was detected in 70%. The majority of isolates belonged to the coagulase-negative staphylococci and Staphylococcus aureus; however, highly pathogenic bacteria were also detected. All were sensitive to all antibiotics except penicillin. Saphenous vein varices contained bacterial cells in 40% and controls 4%; bacterial DNA was found in 69%. The majority of bacteria were S. epidermidis and S. aureus susceptible to all antibiotics except penicillin, Lymph and epifascial lymphatics limb contained bacteria in 60% and 33% samples, respectively and controls in 7%. Most were S. epidermidis susceptible to all antibiotics except penicillin.

Conclusion: Cryptic bacteria are present in lower limb tissues and may play a pathologic role in surgical site infections. Proper antibacterial prophylaxis should be considered when planning surgical interventions.