Abstract
Diagnostic assessment of chronic wounds is essential for the initiation of causal therapeutic treatment. For diagnostic classification of the wound genesis, it may be necessary to take a tissue sample for histological and/or microbiological processing. If there is clinical suspicion of a specific cause of the wound such as a neoplasm, an inflammatory dermatosis or a pathogen-induced wound, a tissue sample for further diagnosis is required immediately. If the ulceration does not respond sufficiently to adequate causal therapy, a tissue sample for further evaluation is recommended after 12 weeks. The choice of the correct sampling technique, further storage, transport and processing are just as decisive for a reliable result as the specific question for the diagnostic laboratory.