The typical patient is elderly and female and over 50% have diabetes, often severe. Additional risk factors include long-term catherisation and immune suppression. Associated commonest infective organisms are Escherichia coli and Klebsiella pneumonia. Most cases are treatable early in the course with antibiotics, bladder drainage, and improved diabetic glucose control.
Pneumaturia or air within the bladder itself without bladder wall air may relate to other causes including prior catheterisation, fistula formation (usually colovesical due to diverticular disease or inflammatory bowel disease) or trauma. The differentiation of intraluminal air from wall air can be made by evaluating the location but also by the usually beaded non-contiguous nature of wall air compared to larger antidependent locules of intravesical air. Repositioning the patient at CT or US can be of assistance.