Wundabstrich

Wundabstrich is a medical procedure in which a sterile swab is used to collect a sample from a wound for microbiological analysis. The aim is to identify causative organisms and guide antimicrobial therapy, particularly when infection is suspected or when colonization may affect healing.

Procedure and technique: To minimize contamination, the wound is cleaned with sterile saline and allowed to dry. A sterile swab is then rotated over the wound bed with firm pressure to collect cells and organisms from viable tissue. A common approach is the Levine technique, which samples a defined area of the wound bed after cleansing. The collected specimen is placed in an appropriate transport medium and sent to the laboratory promptly, with proper handling and storage guidelines followed.

Laboratory processing and interpretation: In the laboratory, samples typically undergo Gram staining and cultures for aerobic and anaerobic bacteria, and sometimes fungal cultures or molecular assays as indicated. Results identify the spectrum of organisms present and their antibiotic susceptibilities. Clinically, results must be interpreted in context, as wound swabs can reflect colonization rather than active infection.

Limitations and alternatives: Swab sampling can be affected by contamination from surrounding skin and may miss deeper or anaerobic infections. In certain cases, tissue biopsy or needle aspiration of the wound bed may provide more reliable information. Quantitative wound cultures or targeted testing may be used for chronic wounds or suspected osteomyelitis, depending on clinical judgment and local guidelines.