What test is recommended for right upper quadrant (RUQ) pain and abdominal discomfort?

From the Guidelines

For patients presenting with right upper quadrant pain and abdominal discomfort, an ultrasound of the abdomen is the recommended first-line test. This recommendation is based on the American College of Radiology's appropriateness criteria for right upper quadrant pain, which suggests that ultrasound is the initial imaging modality of choice for suspected biliary disease 1. The ultrasound's high accuracy in detecting gallstones, with a reported accuracy of 96% 1, makes it an ideal initial test. Additionally, ultrasound can help differentiate between cholelithiasis, gallbladder sludge, polyps, and masses, and may also identify signs of chronic cholecystitis, although the diagnosis of chronic cholecystitis can be challenging on anatomic imaging 1.

Some of the key advantages of using ultrasound as the first-line test include its non-invasive nature, lack of radiation, and quick performance time, making it suitable for emergency settings 1. While cholescintigraphy has been shown to have higher sensitivity and specificity for detecting acute cholecystitis, ultrasound remains the preferred initial test due to its shorter study time, ability to evaluate morphologic changes, and capacity to identify alternative diagnoses 1. However, it's essential to note that the usefulness of ultrasound may be limited in critically ill patients, where gallbladder abnormalities are common in the absence of acute cholecystitis 1.

In cases where complicated cholecystitis is suspected, ultrasound is still the first choice of investigation, as it can detect intraluminal hyperechoic blood products, intraluminal gas, or gas in the gallbladder wall, among other complications 1. A normal appearance of the gallbladder on ultrasound makes acute gallbladder pathology unlikely, further supporting its use as the initial imaging modality 1. Overall, the combination of clinical assessment, laboratory tests, and ultrasound imaging provides a comprehensive approach to diagnosing the cause of right upper quadrant pain and abdominal discomfort.

From the Research

Diagnostic Approach for Right Upper Quadrant Pain

The diagnosis of right upper quadrant (RUQ) pain involves a combination of history, physical examination, laboratory testing, and diagnostic imaging.

• Ultrasound is recommended as the first-line imaging modality for the diagnosis of gallstones and cholecystitis, as it allows for the differentiation of medical and surgical causes of upper abdominal pathology 2, 3.
• Point-of-care ultrasound has a high sensitivity and specificity for cholelithiasis and can help emergency physicians determine whether the biliary system is the source of infection in patients with suspected sepsis 4.
• The use of ultrasound as the initial imaging modality can guide patient management and reduce the need for further testing 2, 3.
• In cases where ultrasound is indeterminate, other imaging modalities such as computed tomography (CT), MR imaging, and radionuclide imaging may be used to establish a diagnosis 3.
• A logical diagnostic approach should be based on clues obtained from careful history taking, physical examination, and review of routine laboratory studies, with the use of sophisticated tests such as endoscopic retrograde cholangiopancreatography with sphincter manometry in refractory cases 5.

Imaging Modalities for RUQ Pain

• Ultrasound is the initial imaging modality of choice for most hepatobiliary disorders 3.
• CT and MR imaging may be used to evaluate the liver, gallbladder, and biliary tree, especially in cases where ultrasound is indeterminate 3.
• Radionuclide imaging may be used to evaluate the biliary system and diagnose conditions such as choledocholithiasis 3.
• Point-of-care ultrasound can be used to rapidly diagnose biliary problems and reduce emergency department length of stay 4.

Clinical Evaluation of RUQ Pain

• A combination of history, physical examination, laboratory testing, and diagnostic imaging is required to evaluate patients with RUQ pain 6.
• The differential diagnosis for RUQ pain is broad and includes gastrointestinal and non-gastrointestinal causes 6.
• A careful history and physical examination can help identify the cause of RUQ pain and guide further testing and management 6, 5.