The Significance of Murphy Sign in Diagnosing Gallbladder Disease
The Murphy sign has moderate diagnostic value for acute cholecystitis but should not be used alone, as it has relatively low specificity (35-81%) and must be combined with other clinical, laboratory, and imaging findings for accurate diagnosis of gallbladder disease. 1
Definition and Clinical Application
- Murphy sign is defined as focal tenderness corresponding to a sonographically localized gallbladder, which helps differentiate acute cholecystitis from gallstones alone and chronic cholecystitis with gallstones 1
- It is elicited when a patient experiences increased pain and stops breathing during deep palpation of the right upper quadrant of the abdomen during inspiration 1
- The sign is considered a useful feature in the clinical examination for suspected acute cholecystitis, alongside fever, right upper quadrant pain/tenderness, vomiting, and food intolerance 1
Diagnostic Value
Strengths
- Positive likelihood ratio of 2.8 (95% CI 0.8-8.6) for acute cholecystitis, though confidence intervals include 1.0 1
- When combined with gallstones on ultrasound, positive predictive value increases to 77-99% for acute cholecystitis 2, 3
- Negative Murphy sign combined with absence of gallstones has excellent negative predictive value (95%) for excluding acute cholecystitis 2
Limitations
- Relatively low specificity for acute cholecystitis when used alone 1
- Sensitivity ranges from 63-86% with specificity of 35-93.6% across different studies 3, 4
- Unreliable as a negative predictor if the patient has received pain medication prior to examination 1
- Cannot reliably distinguish between acute and chronic cholecystitis when used alone 3
Role in Diagnostic Algorithm
No single clinical or laboratory finding has sufficient diagnostic power to establish or exclude acute cholecystitis 1
For optimal diagnosis, Murphy sign should be used in combination with:
The triad of positive Murphy sign, elevated neutrophil count, and ultrasound showing cholelithiasis or cholecystitis yields:
- Sensitivity: 74%
- Specificity: 62%
- Positive predictive value: 80%
- Negative predictive value: 53% 5
Sonographic Murphy Sign
- Ultrasound is the first-choice investigation for biliary symptoms or right upper quadrant pain (96% accuracy for detecting gallstones) 1
- Sonographic Murphy sign (tenderness elicited over sonographically localized gallbladder) improves diagnostic accuracy when combined with other ultrasound findings 1, 2
- When combined with stones and gallbladder wall thickening, sonographic Murphy sign has excellent positive predictive value (92-95%) for acute cholecystitis 2
- Real-time sonography using both primary (stones) and secondary signs (Murphy sign, wall thickening) can be definitive in nearly 80% of patients with suspected acute cholecystitis 2
Clinical Pitfalls and Caveats
- Murphy sign may be absent in elderly, diabetic, or immunocompromised patients despite severe gallbladder disease 1
- Administration of pain medications prior to examination invalidates the reliability of a negative Murphy sign 1
- In critically ill patients, gallbladder abnormalities are common even in the absence of acute cholecystitis, limiting the usefulness of ultrasound findings including Murphy sign 1
- Complicated cholecystitis (emphysematous, hemorrhagic, gangrenous, or perforated) may present with similar clinical findings as uncomplicated disease, requiring additional imaging studies beyond ultrasound 1
Current Best Practice
- Ultrasound remains the initial test of choice for imaging patients with suspected acute cholecystitis despite cholescintigraphy having higher sensitivity and specificity 1
- The combination of clinical, laboratory, and imaging findings provides the most accurate diagnosis of gallbladder disease 1
- When Murphy sign is positive along with other supportive findings, early laparoscopic/open cholecystectomy (within 7-10 days of symptom onset) is recommended for uncomplicated cholecystitis 1