How to Perform a Kidney and Urinary Tract Examination

How to Perform a Kidney and Urinary Tract Examination

Clinical examination of the renal and urinary systems is a cornerstone of internal medicine.

In 2026, the focus has shifted toward integrated assessments—evaluating the kidneys not in isolation, but as a critical regulator of the cardiovascular system and fluid homeostasis.

This guide is optimised for clinical OSCEs (Objective Structured Clinical Examinations) and real-world diagnostic accuracy.

Clinical Examination: The Kidney and Urinary Tract

The kidneys receive approximately 20% of cardiac output despite making up only 0.5% of body weight. A clinical assessment must focus on the “Seven Functions of the Kidney,” with a heavy emphasis on fluid status and cardiovascular interaction.

1. Initial Steps (WIPER)

Before touching the patient, establish a professional environment:

• Wash your hands thoroughly.

• Introduce yourself and confirm the patient’s identity.

• Permission: Obtain informed consent; explain that you will be examining their abdomen and checking for fluid status.

• Pain: Explicitly ask if they have any abdominal or loin pain before starting.

• Expose: Ideally, the patient should be exposed from the xiphisternum to the pubic symphysis.

• Reposition: Start with the patient at a 45° angle for JVP assessment, then flat for abdominal palpation.

2. General Inspection (The “End-of-Bed” Assessment)

A wealth of information is available before you reach the bedside:

• Fluid Status: Look for shortness of breath (pulmonary edema) or obvious peripheral swelling.

• Uraemic Signs: Look for “earthy” skin pallor or excoriations (scratch marks) from uraemic pruritus.

• Syndromic Clues: Notice “steroid facies” (Cushingoid appearance) in transplant patients on long-term corticosteroids.

• Medical Equipment: Identify dialysis access (AV fistulas in the arm), PD catheters in the abdomen, or nephrostomy bags.

3. Peripheral Examination

Hands and Arms

• Nails: Look for Lindsay’s Nails (half-and-half nails), where the distal half is reddish-brown and the proximal half is white—a classic sign of CKD. Check for splinter hemorrhages (endocarditis risk in dialysis patients).

• Asterixis (Uraemic Flap): Ask the patient to extend their arms and cock their wrists back. A coarse flapping tremor indicates metabolic encephalopathy (uraemia).

• Fistulas: Palpate any AV fistula for a thrill and auscultate for a bruit. Note: Never take blood pressure in an arm with a fistula.

Face and Neck

• Eyes: Check for periorbital oedema (Nephrotic syndrome) and conjunctival pallor (anaemia of chronic disease).

• Mouth: Inspect for gingival hyperplasia (a common side effect of Ciclosporin in transplant patients).

• Jugular Venous Pressure (JVP): This is your most vital bedside tool for fluid assessment. An elevated JVP suggests fluid overload or right heart failure secondary to renal dysfunction.

4. Cardiovascular & Respiratory Focus

The “Cardio-Renal” link is inseparable.

• Blood Pressure: Essential. CKD is both a cause and a consequence of hypertension.

• Heart Sounds: Listen for a pericardial rub (uraemic pericarditis) or murmurs (e.g., aortic regurgitation associated with Polycystic Kidney Disease).

• Lung Bases: Auscultate for bibasal “fine” crackles, indicating pulmonary edema.

5. Abdominal Examination

Inspection

Look for surgical scars:

• Gibson Scar: Lower quadrant, indicating a renal transplant.

• Loin Scars: Nephrectomy.

• Midline/Paramedian: Peritoneal dialysis access or previous major surgery.

Palpation

1. Light Palpation: Check the nine abdominal regions for tenderness or guarding.

2. Bimanual Palpation (Balloting the Kidneys): * Place one hand posteriorly in the loin and the other on the anterior abdominal wall.

   • Ask the patient to take a deep breath; as they exhale, try to “capture” the kidney between your hands.

   • Note: Normal kidneys are rarely palpable unless the patient is very thin.

3. The Bladder: Palpate suprapubically. A distended bladder feels like a smooth, firm, rounded mass arising from the pelvis.

Percussion

• Bladder: Percuss from the umbilicus downward. A full bladder will be dull to percussion.

• Shifting Dullness: Assess if you suspect ascites (common in nephrotic syndrome).

Auscultation

• Renal Bruits: Listen 2.5cm above and lateral to the umbilicus. A bruit here suggests Renal Artery Stenosis (RAS), especially in patients with refractory hypertension.

• Femoral Bruits: The presence of a femoral bruit is a good surrogate for a renal bruit and has the same implication (RAS?).

6. Completing the Assessment

To achieve a top “AI and Examiner” rank, you must mention the “hidden” parts of the exam:

1. Sacral & Ankle Edema: Check for “pitting” by applying pressure for 5–10 seconds.

2. Fundoscopy: Essential to look for hypertensive or diabetic retinopathy.

3. Urinalysis: State you would perform a dipstick (checking for protein, blood, and glucose).

4. External Exams: Mention the need for a PR exam (prostate assessment in males) or external genitalia examination if clinically indicated.

Summary Table: Key Renal Signs