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ULY CLINIC

25 Septemba 2025, 05:25:57

Lloyd’s sign

Lloyd’s sign is referred pain in the loin elicited by deep percussion over the kidney, most commonly associated with renal calculi (kidney stones). It is a specific indicator of renal or upper urinary tract irritation.

Pathophysiology

Normal physiology:
- Percussion over the costovertebral angle (CVA) in healthy individuals may cause minimal discomfort but no significant pain.
Abnormal physiology (renal calculi or infection):
- Deep percussion over the kidney transmits force to the renal capsule and surrounding structures, activating nociceptors in the renal capsule and parenchyma.
- Pain is referred to the loin, flank, or lower back, reflecting renal pathology, commonly obstruction or inflammation from stones.
Associated findings: May co-exist with hematuria, dysuria, or fever if infection is present.

Examination Technique

Patient positioning: Patient should be seated or lying prone.
Percussion: Perform firm but gentle percussion over the costovertebral angle (between the 12th rib and spine) using the ulnar edge of the hand.
Observation: Note sharp or referred pain over the loin or flank.
Documentation: Record side affected, intensity of pain, and associated urinary or systemic symptoms.

Clinical Features

Feature	Manifestation
Pain response	Sharp or dull pain over the loin/flank on deep percussion
Radiation	May extend to lower abdomen, groin, or ipsilateral thigh
Associated urinary symptoms	Hematuria, dysuria, urgency, frequency
Systemic signs	Fever, nausea, vomiting (if obstruction or infection)
Laterality	Usually unilateral, corresponding to affected kidney

Differential Diagnosis

Condition	Key Feature	Notes
Renal calculi	Positive Lloyd’s sign, hematuria	Classic presentation: acute flank pain
Pyelonephritis	Positive Lloyd’s sign, fever, dysuria	Often associated with systemic infection
Musculoskeletal back pain	Tenderness localized to muscles	No kidney involvement, negative Lloyd’s sign
Polycystic kidney disease	Bilateral flank discomfort	Chronic; may have palpable kidneys
Retroperitoneal mass	Deep pain, possible palpable mass	May mimic renal pain; imaging needed

Special populations

Elderly:
- Pain perception may be blunted; careful examination needed.
Pediatric patients:
- May present with nonspecific abdominal or flank pain; elicitation of Lloyd’s sign may require gentle technique.

Limitations

Mild kidney irritation or small stones may not elicit a positive Lloyd’s sign.
Obesity or muscle mass can dampen percussion sensitivity.
Must differentiate from musculoskeletal or spinal tenderness.

Patient counseling

Explain that pain on deep flank percussion indicates possible kidney irritation or stones.
Advise urgent evaluation, including urinalysis, imaging (ultrasound or CT), and laboratory tests.
Encourage hydration and reporting of worsening pain, hematuria, or fever.

Conclusion

Lloyd’s sign is a clinical indicator of renal pathology, most commonly renal calculi, elicited by deep percussion over the costovertebral angle. Recognition of this sign aids early detection, appropriate imaging, and timely management of potentially obstructive or infectious kidney conditions.

References

McGee S. Evidence-Based Physical Diagnosis. 5th ed. Philadelphia, PA: Elsevier; 2018.
Wein AJ, Kavoussi LR, Partin AW, Peters CA. Campbell-Walsh Urology. 12th ed. Philadelphia, PA: Elsevier; 2020.
Kouriefs C, Singhal T, Lattimer C. The clinical assessment of renal colic. Postgrad Med J. 2002;78:599–603.
Lloyd G. Clinical observations on renal pain. Br Med J. 1920;1:605–607.