Final answer:
The presence of pus from the lumen or wall of the gallbladder is a specific indicator of empyema, which is a severe infection that requires urgent medical treatment.
Step-by-step explanation:
The presence of pus from the lumen or wall of the gallbladder (GB) is a specific indicator of empyema. In the context of gallbladder conditions, empyema is a complication characterized by the accumulation of purulent material within the gallbladder, and its diagnosis often involves imaging and clinical assessment. The presence of pus is highly suggestive of infection and dictates the need for urgent medical intervention, typically including antibiotic therapy and possibly surgical drainage.