A sonographic Murphy’s sign is a specific finding during a gallbladder ultrasound where you feel sharp tenderness when the technician or doctor presses the ultrasound probe directly over your gallbladder. It’s one of the key indicators used to diagnose acute cholecystitis, which is sudden inflammation of the gallbladder, usually caused by gallstones. Unlike a standard physical exam, the ultrasound version of this test lets the examiner see exactly where the gallbladder sits and press on that precise spot, making it more targeted than pushing on the general area of your abdomen by hand.
How the Test Works
During a regular abdominal ultrasound, the person performing the scan uses the probe to locate your gallbladder on screen. Once they can see it clearly, they press the probe firmly into your abdomen directly over the gallbladder. If that pressure produces a sharp, focused pain right at that spot, the sonographic Murphy’s sign is considered positive. A negative result means you don’t feel significant tenderness when the probe pushes on the gallbladder.
The whole maneuver takes only a few seconds. You’ll likely already be lying on your back for the ultrasound, and the examiner may ask you to take a deep breath and hold it, which brings the gallbladder lower and makes it easier to press against. The pressure can be uncomfortable even in healthy people, but what the examiner is looking for is a distinct, wincing pain that’s clearly worse over the gallbladder compared to surrounding areas. Some people instinctively catch their breath or pull away, which is itself a telling response.
Why It Matters for Diagnosing Gallbladder Inflammation
Acute cholecystitis is the most common reason for a positive sonographic Murphy’s sign. When a gallstone gets stuck in the duct that drains the gallbladder, bile backs up, the gallbladder swells, and the wall becomes inflamed. That inflammation makes the tissue extremely sensitive to pressure, which is exactly what the probe is testing for.
The Tokyo Guidelines, an international standard for diagnosing acute cholecystitis, list the sonographic Murphy’s sign as one of the primary ultrasound findings. But it’s rarely used in isolation. Doctors look for it alongside other ultrasound clues: gallbladder wall thickening greater than 4 millimeters, an enlarged gallbladder (longer than 8 centimeters or wider than 4 centimeters), gallstones lodged in the neck of the gallbladder, fluid collecting around the gallbladder, and debris floating inside it. When a positive sonographic Murphy’s sign appears together with gallstones and wall thickening, the diagnosis of acute cholecystitis becomes much more confident.
How Accurate Is It?
The sonographic Murphy’s sign is better at ruling cholecystitis in than ruling it out. Its specificity, meaning how well it identifies people who don’t have the condition, has been reported as high as 93.6% in prospective studies. That means a positive result is a strong signal that something is genuinely wrong with the gallbladder. Its sensitivity, the ability to catch all true cases, is more variable. One well-known prospective study found sensitivity at 63%, while another reported it closer to 86%. The gap depends on the patient population and the skill of the examiner.
In practical terms, a positive sonographic Murphy’s sign is a fairly reliable red flag, especially combined with other findings. But a negative result doesn’t necessarily clear you. Roughly one in three to four people with genuine gallbladder inflammation may not show tenderness during the ultrasound, so doctors don’t rely on this sign alone to make or dismiss the diagnosis.
When the Sign Can Be Misleading
Several factors can produce a false negative, meaning the sign comes back negative even though the gallbladder is inflamed. The most clinically important is gangrenous cholecystitis, a severe form where the gallbladder wall has started to die. Paradoxically, the nerves in the wall may no longer transmit pain signals, so pressing on it doesn’t hurt. This is dangerous because gangrenous cholecystitis is an emergency, and the absence of tenderness can create a false sense of reassurance.
Patients who have received pain medication before the ultrasound may also show a blunted response, though research suggests that standard doses of analgesics don’t completely eliminate the sign in most cases. People with a high pain tolerance, those who are heavily sedated, or elderly patients with diminished pain perception can also produce unreliable results.
On the other side, false positives can occur. Conditions like peptic ulcer disease, hepatitis, or even severe gas in the intestines near the gallbladder can cause right upper abdominal tenderness that mimics a positive sonographic Murphy’s sign. The examiner tries to minimize this by confirming the probe is directly over the gallbladder on the screen, but overlap with nearby structures is always possible.
How It Differs From a Clinical Murphy’s Sign
The original Murphy’s sign is a bedside physical exam technique where a doctor places their hand below your right rib cage and asks you to breathe in deeply. As the diaphragm pushes the gallbladder down against the examiner’s fingers, a sharp catch of pain or a sudden stop in breathing is a positive Murphy’s sign. This version doesn’t use imaging, so the doctor is estimating where the gallbladder is based on anatomy.
The sonographic version improves on this by letting the examiner see the gallbladder in real time. They know the probe is sitting directly over the organ, not over the liver, colon, or another nearby structure. This precision is why the sonographic Murphy’s sign is generally considered more reliable than the clinical version, and why it’s become a standard part of the gallbladder ultrasound when acute cholecystitis is suspected. It also gives the examiner the ability to check for stones, wall changes, and fluid at the same time, turning a single ultrasound session into both a structural and functional assessment of the gallbladder.