Diagnosis of cholangitis typically involves a combination of clinical evaluation, laboratory tests, and imaging studies. Blood tests may show elevated liver enzymes, bilirubin levels, and white blood cell count. Ultrasonography and Magnetic Resonance Cholangiopancreatography (MRCP) are commonly used imaging techniques to identify bile duct obstructions and inflammation. In some cases, an Endoscopic Retrograde Cholangiopancreatography (ERCP) may be required for both diagnosis and treatment.