Acute emphysematous cholecystitis is a rare entity (1% of acute cholecystitis) characterized by the presence of gas in the gallbladder lumen, gallbladder wall or even in the bile duct (pneumobilia). It is associated with arteriosclerosis, embolic events, and diabetes mellitus and as in other similar pathologies such as emphysematous gastritis or emphysematous pancreatitis the most frequently isolated microorganisms are Streptococcus pyogenes, Escherichia coli and Staphylococcus aureus, although others such as Proteus vulgaris, Pseudomonas aeruginosa, Clostridium perfringens and Klebsiella pneumoniae have also been found.