If you're on peritoneal dialysis, your doctor may be able to diagnose peritonitis simply by your signs and symptoms, particularly if you are experiencing cloudy dialysis fluid.
If your doctor needs further confirmation or if the infection may be a result of other medical conditions, your doctor will most likely perform a physical exam of your abdomen to feel if it is unusually tender or firm.
Your healthcare provider may also conduct one or more of these tests:
Peritoneal fluid analysis is done by using a thin needle to take a sample of the fluid in your peritoneum. An elevated white blood cell count in the fluid may indicate an infection or inflammation, and a culture of the fluid may also indicate if bacteria are present.
Blood tests can also reveal if you have a high white blood cell count, and a blood culture can determine if there are bacteria in your blood.
Imaging tests, such as an X-ray, ultrasound, or computerized tomography (CT) scan can check for fluid, gas, masses, or abscesses in your abdomen. or other perforations in your gastrointestinal tract.