Hematuria and Proteinuria: A Symptom-Based Diagnostic Guide for OSCE and Clinical Practice

“You have blood in your urine.”
“Your test shows protein in the urine.”
How should we respond to these findings? Could it be glomerulonephritis? A urinary tract infection? Or just a temporary, benign change?
This article outlines a systematic approach to evaluating hematuria and proteinuria—two frequently encountered but potentially serious findings in outpatient and screening settings.
With a focus on clinical reasoning, this guide is ideal for OSCE preparation and daily practice in general medicine.

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📘 What You Will Learn

• How to interpret and classify hematuria and proteinuria correctly
  — Learn the differences between gross vs. microscopic hematuria and understand the diagnostic criteria for nephrotic syndrome.
• How to differentiate glomerular from non-glomerular causes
  — Identify key findings in urinalysis such as RBC morphology, casts, and associated clinical clues.
• A structured approach for OSCE and real-world practice
  — Master the diagnostic process using patient history, physical examination, and targeted investigations.

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🧑‍⚕️ Case Introduction: 50-Year-Old Man with Gross Hematuria

Doorway Information
Age: 50-year-old man
Chief complaint: Gross hematuria
Vital signs: BP 130/78 mmHg, HR 84 bpm, Temp 36.8°C, SpO₂ 98% (room air)

“Doctor, yesterday when I went to the bathroom, my urine was bright red. I was shocked. There’s no pain, but this has never happened before.”

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🧭 How Should We Think About Hematuria and Proteinuria?

Hematuria and proteinuria are common abnormal findings often detected in routine urine tests or outpatient visits.
While sometimes benign, they can also signal serious underlying conditions such as glomerulonephritis, urinary tract malignancy, or diabetic nephropathy.

The first two steps in approaching these findings are:

1. Step 1: Is it truly hematuria or proteinuria?
   Not all red urine is hematuria. Consider pseudohematuria from beet ingestion, hemoglobinuria, or myoglobinuria.
   Always confirm red blood cells under the microscope after a positive dipstick test.
   For proteinuria, rule out transient or false-positive causes such as fever, exercise, orthostatic proteinuria, or alkaline urine.
2. Step 2: Where is the abnormality coming from?
   In hematuria, the key is to distinguish between glomerular and non-glomerular sources.
   ─ Dysmorphic RBCs or RBC casts → Glomerular (e.g., nephritis)
   ─ Isomorphic RBCs or visible clots → Non-glomerular (e.g., malignancy, infection, stones)
   Proteinuria can also be categorized into four types: glomerular, overflow, tubular, and post-renal.

By organizing your thinking as:
“Is it real?” → “Where is it from?” → “What is the cause?”
you can approach hematuria and proteinuria with much greater clarity.

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🧠 Initial Reasoning from Doorway Information: Fact / Problem / Hypothesis

At this point, before any additional questioning or physical examination, let’s try to construct a differential diagnosis based solely on the patient’s initial words and vital signs.

📌 Doorway Information

• 50-year-old male
• Chief complaint: Gross hematuria (“bright red urine”)
• No pain or associated symptoms
• Vital signs: BP 130/78 mmHg, HR 84 bpm, Temp 36.8°C, SpO₂ 98% (RA)

🗣️ Chief Complaint (Patient’s words)

“Doctor, yesterday when I went to the bathroom, my urine was bright red. I was shocked. There’s no pain, but this has never happened before.”

🟩 Fact (Clinical observations from limited information)

• Gross hematuria (self-reported bright red urine)
• Painless episode
• First-time occurrence
• Stable vital signs and general condition

🟦 Problem (Reframing the issue)

• Painless gross hematuria in a middle-aged man
• No dysuria, fever, or flank pain
• Unlikely to be infection or stone based on initial clues

🟥 Hypothesis (Initial differential diagnosis based on VITAMIN CDE framework)

• Must-not-miss causes:
  • Urothelial carcinoma (bladder, renal pelvis, ureter)

    — Classic presentation: painless gross hematuria in patients >50 years

    — Risk factors: smoking history, occupational exposure

• Common causes to rule out next:
  • Urinary stones (can be painless)
  • Prostate disease (BPH, prostatitis, prostate cancer)
• Glomerular disease (less likely based on this case but still possible):
  • IgA nephropathy (especially in younger men)
  • Post-infectious glomerulonephritis (typically in children/young adults)
  • ANCA-associated vasculitis (usually with other systemic signs)

🔍 NTK – Need To Know (What we want to ask next)

• Color and duration of hematuria
• Presence of clots (suggests non-glomerular source)
• Fever, dysuria, flank/back pain → infections, stones
• Any history of similar findings on checkups?
• Smoking history, occupational exposure (e.g., chemicals, dyes)
• Medications (e.g., NSAIDs, anticoagulants), trauma, recent strenuous exercise

➡️ At this point, urothelial malignancy is the top concern, and the history should focus on identifying risk factors and ruling out infection or stone.

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🩺 Step 1: History Taking – Differentiating Hematuria and Proteinuria

When a patient presents with hematuria or proteinuria, the differential diagnosis depends on the underlying mechanism.
Therefore, history taking should be customized for each presentation. Let’s break down the key questions and clinical insights for both.

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🩸 A. Approach to Hematuria – Use OPQRST

Element	Example Questions and Clinical Implications
O (Onset)	“When did you first notice red urine?” → Acute: infection/stones; Chronic: malignancy/nephropathy
P (Provocation/Palliation)	“After exercise or a cold?” → Think IgA nephropathy, stones
Q (Quality)	“Was the urine pink, brown, or did you see clots?” → Brown: glomerular; Clots: non-glomerular
R (Region/Radiation)	“Any flank or lower abdominal pain?” → Suggests stones, pyelonephritis
S (Severity)	“Was the urine completely red or just tinged?” → Degree of bleeding
T (Timing)	“Was it once or recurring?” → Persistent vs. transient hematuria

Ask about pain and hematuria pattern:

• Painless gross hematuria → Rule out malignancy (e.g., bladder cancer)
• Painful hematuria → Think stones, infection, urethral trauma
• Fever with hematuria → Consider pyelonephritis, renal abscess, endocarditis

🛠️ Tips: Hematuria Localization by Timing

• Initial hematuria → Urethral source
• Terminal hematuria → Bladder neck or prostate
• Total hematuria → Renal or upper tract source

🧠 Column: When It’s Not Really Hematuria

• Foods: Beets, rhubarb
• Drugs: Rifampin, senna, metronidazole
• Hemoglobinuria/Myoglobinuria: Dipstick positive, but no RBCs on microscopy → Suspect rhabdomyolysis or hemolysis

🔍 PAM HITS FOSS – Hematuria Red Flags

• NSAID or anticoagulant use
• Smoking history
• Occupational exposure to chemicals, dyes, paints
• Recent urologic procedures, catheter use
• Sexual history (STIs, trauma)
• Family history of kidney disease or cancer (e.g., ADPKD, Alport)

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🧪 B. Approach to Proteinuria

• “Have you noticed foamy or bubbly urine?” → Suggestive of proteinuria
• “Were you sick, exercising, or dehydrated when the test was done?” → May indicate transient proteinuria
• Any history of diabetes, hypertension, autoimmune disease?
• Medication history: NSAIDs, antibiotics, or herbal supplements?
• Any swelling in your legs or face? (→ nephrotic syndrome)

🛠️ Tips: How to Confirm True Proteinuria

• Is it persistent across multiple tests?
• Was the sample collected first thing in the morning?
• Transient causes (e.g., fever, dehydration, exercise) should be ruled out

🧠 Column: Diagnostic Criteria for Nephrotic Syndrome

• Proteinuria > 3.5 g/day
• Hypoalbuminemia (Alb < 3.0 g/dL)
• Edema
• Hyperlipidemia and increased risk of thrombosis

🔍 PAM HITS FOSS – Proteinuria Risk Factors

• History of diabetes, hypertension, autoimmune disease
• Use of nephrotoxic medications
• Pregnancy-related complications (e.g., preeclampsia)
• Family history of hereditary kidney diseases (e.g., FSGS, Alport)
• Exercise, stress, fluid intake

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💡 Clinical Clues: Symptom Combinations to Guide Differential

Symptom Pattern	Likely Diagnosis
Hematuria + colicky flank pain	Urinary stones
Hematuria + fever + dysuria	UTI (cystitis, pyelonephritis)
Painless hematuria + age >50 + smoking	Bladder or upper tract malignancy
Hematuria + brown urine + post-infection	IgA nephropathy, PSAGN
Proteinuria + edema + frothy urine	Nephrotic syndrome
Proteinuria + HTN + long-standing diabetes	Diabetic nephropathy
Hematuria/Proteinuria + joint pain + purpura	Vasculitis, collagen vascular disease
Hematuria + NSAID use	Drug-induced interstitial nephritis
Proteinuria + fever + arthralgia	SLE, MCTD
Proteinuria + pregnancy/postpartum	Preeclampsia

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🩺 Step 2: Physical Examination – Identifying the Underlying Cause

Physical examination helps validate hypotheses formed during history taking.
In cases of hematuria and proteinuria, both local and systemic findings may offer diagnostic clues.
Let’s explore a structured approach for each.

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🧪 A. Approach to Hematuria – What to Look For

• General appearance: fever, chills, tachycardia → think infection/sepsis
• Flank/Costovertebral angle (CVA): tenderness → pyelonephritis, stones
• Suprapubic area: distention or tenderness → bladder mass or retention
• Digital rectal exam (DRE): prostate enlargement, firmness, tenderness → BPH, prostatitis, or cancer
• External genitalia and urethra: erosions, bleeding, discharge → STI or trauma

🧠 Tips: How Physical Findings Guide Your Diagnosis

Finding	Possible Diagnosis
CVA tenderness (+)	Pyelonephritis, ureteral stone
Fever + tachycardia	Infectious cause (UTI, pyelonephritis)
Palpable suprapubic mass	Bladder tumor, large prostate, urinary retention
DRE: enlarged or firm prostate	BPH, prostate cancer
Genital ulcers or discharge	Urethritis, STI

🔍 Column: Comparing Physical Findings – Pyelonephritis vs Stones vs Tumor

• Pyelonephritis: Fever, CVA tenderness, systemic symptoms
• Urinary stone: Severe flank pain, CVA tenderness, pain migration
• Bladder cancer: Usually painless, minimal findings on exam; may palpate mass in advanced cases

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💧 B. Approach to Proteinuria – Think Systemic

• Edema: periorbital or pitting pedal edema → nephrotic syndrome
• Blood pressure: sustained hypertension suggests progressive renal disease
• Skin and mucosa: purpura, oral ulcers, Raynaud’s → possible vasculitis or autoimmune disease
• Joint exam: arthritis or joint swelling → SLE, MCTD
• Lungs and nerves: crackles, neuropathy → EGPA, systemic disease

🧠 Tips: Characteristic Physical Signs by Disease Type

Condition	Typical Physical Signs
Nephrotic syndrome	Edema (eyelids, legs), normotension to low BP, otherwise well-appearing
Diabetic nephropathy	Retinopathy, peripheral neuropathy, carpal tunnel, longstanding diabetes
ANCA-associated vasculitis	Purpura, fever, lung crackles, mononeuritis multiplex (e.g., EGPA with asthma history)

🔍 Column: “Systemic Clues” to Suspect Kidney Disease

Kidney disorders often have few local symptoms.
So it’s essential to integrate findings such as edema, BP, skin lesions, joint findings, or nerve signs to build a systemic picture.

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🔬 Step 3: Diagnostic Workup – Investigating the Cause of Hematuria and Proteinuria

After thorough history and physical exam, appropriate laboratory and imaging tests will help confirm or refute your differential diagnoses.
Let’s go through a practical, evidence-based approach for both hematuria and proteinuria.

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🩸 A. Workup for Hematuria

✅ Initial Laboratory Tests

• Urinalysis (dipstick and microscopy):
  • RBC morphology → dysmorphic (glomerular) vs isomorphic (non-glomerular)
  • RBC casts → glomerulonephritis
  • WBCs, nitrites, bacteria → infection
  • Clots → typically non-glomerular source
• Urine culture: if UTI is suspected (fever, dysuria, etc.)
• Urine cytology: low sensitivity, but helpful for urothelial cancer screening in high-risk cases

🧠 Tips: Three Angles to Assess Hematuria

• Urine exam: morphology, casts, infection signs, clots
• Imaging: anatomical abnormalities (stones, masses)
• Cystoscopy: consider in all patients over 50 with gross hematuria

🔍 Column: M-I-S-T-E-R Mnemonic for Non-Glomerular Hematuria

• M: Malignancy (bladder, renal pelvis, ureter)
• I: Infection (UTI, prostatitis)
• S: Stone (renal or ureteral)
• T: Trauma (catheter, injury)
• E: Exercise (rare, transient)
• R: Renal (non-glomerular causes)

🖥️ Imaging Selection Guide

Purpose	Recommended Test
Evaluate for stones	Renal ultrasound + KUB X-ray; CT if unclear
Assess urinary tract tumors	Ultrasound → contrast-enhanced CT (CT urography)
Investigate pyelonephritis	Ultrasound or contrast CT (look for abscess or masses)

🧠 Column: Don’t Miss Pseudo-Hematuria

• Foods: Beets, blackberries, food dyes
• Drugs: Rifampin, senna, metronidazole
• Hemoglobinuria / Myoglobinuria: positive dipstick but no RBCs on microscopy

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💧 B. Workup for Proteinuria

✅ Key Tests

• Dipstick test: good screening tool, but may have false positives
• Quantification:
  • 24-hour urine protein
  • Spot urine protein/creatinine ratio (UPCR)
  • Albumin/creatinine ratio (UACR): especially in diabetes screening
• Urine microscopy:
  • Granular casts or fatty casts → nephrotic syndrome
  • WBCs or eosinophils → interstitial nephritis

🧠 Tips: 4 Types of Proteinuria

• Glomerular: increased permeability (e.g., nephrotic syndrome)
• Overflow: excessive protein production (e.g., myoglobin, Bence-Jones)
• Tubular: impaired reabsorption (e.g., tubulointerstitial nephritis)
• Post-renal: contamination from infection or bleeding

🩸 Blood Tests to Add

Test	Purpose
Creatinine, eGFR	Assess kidney function
Serum albumin	↓ in nephrotic syndrome
LDL, triglycerides	↑ in nephrotic syndrome
C3, C4	↓ in immune-mediated nephritis (e.g., MPGN, lupus)
ANCA, ANA, anti-dsDNA	Autoimmune disease or vasculitis screen

🧠 Topic: Staging Diabetic Nephropathy

Stage	Key Findings
Stage 1–2	Asymptomatic, normal urine protein
Stage 3	Microalbuminuria (UACR 30–300 mg/g)
Stage 4	Macroalbuminuria (UACR >300 mg/g)
Stage 5	eGFR decline, ESRD, may require dialysis

🧪 Column: FENa vs FEUN – How to Tell Volume Depletion from Renal Injury

Index	Interpretation	Notes
FENa < 1%	Pre-renal (volume depletion, hypoperfusion)	Suggests sodium retention
FENa > 2%	Intrinsic renal injury	Suggests tubular damage
FEUN < 35%	Also indicates pre-renal cause	More reliable with diuretic use

👉 When on diuretics, rely on FEUN over FENa for better diagnostic accuracy.

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🔁 Case Reflection: Applying Step 1–3 to Our Patient

Now that we’ve reviewed the general approach, let’s go back to our 50-year-old male patient who presented with painless, gross hematuria.
We’ll apply each step to see how clinical reasoning unfolds in practice.

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🟩 Step 1: History Taking

What we asked:

• Onset: Sudden, first-time episode of bright red urine
• Associated symptoms: No fever, no dysuria, no flank or abdominal pain
• Timing: One-time episode, no recurrence so far
• Clots: Unknown at initial interview

PAM HITS FOSS revealed:

• Occasional NSAID use
• 30 pack-year smoking history
• Occupational exposure: long history of working with paints and industrial solvents

Clinical thought process:

Hmm… this is a middle-aged man with painless gross hematuria.
No signs of infection or stones. The red flags are there: smoking history and chemical exposure.
Bladder or urothelial cancer is moving up my differential list.

• Fact: Painless gross hematuria in a 50-year-old man with smoking and NSAID use
• Problem: Atypical urinary finding in a high-risk male with no other symptoms
• Hypothesis: Urothelial carcinoma is most likely; stones, BPH, and glomerular disease are also on the list

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🩺 Step 2: Physical Examination

• No fever or tachycardia
• Negative CVA tenderness → makes pyelonephritis or stones less likely
• No palpable bladder mass or signs of urinary retention
• External genital exam: normal, no urethral discharge or lesions
• DRE: slightly enlarged prostate, no tenderness or nodules

Clinical impression:

Okay… nothing really points to infection or stones here.
No signs of glomerulonephritis either. With no signs of systemic illness and stable vitals, tumor still feels like the most likely culprit.

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🔬 Step 3: Labs and Imaging

• Urinalysis: 3+ blood, negative for protein
• Microscopy: abundant RBCs, isomorphic in shape; no RBC casts
• Urine cytology: atypical cells (suspicious, needs follow-up)
• Urine culture: negative
• Abdominal ultrasound: normal kidneys and ureters, but hypoechoic bladder mass noted
• Contrast CT: enhancing lesion within the bladder (T2 hyperintense)

Interpretation:

This supports a non-glomerular source.
The presence of isomorphic RBCs and imaging findings strongly suggest bladder cancer.
Urine cytology also supports this. Referral to urology is now essential.

🟢 Final Assessment

• Likely diagnosis: Bladder cancer (non-glomerular hematuria)
• Next step: Refer to urology for cystoscopy and biopsy
• Ruling out: Stones, UTI, glomerular disease, drug-induced bleeding

🧠 Tip: Don’t forget to ask about smoking history in pack-years. In this case, 30 pack-years is a significant risk factor.

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📨 When to Refer – Urology Referral Guide

So when should you involve a urologist in cases of hematuria or proteinuria?
Here are the key clinical situations that warrant prompt referral.

🔍 Indications for Urology Referral

• Any gross hematuria, especially in patients ≥40 years old
• Imaging reveals a mass in the bladder, ureter, or kidney
• Asymptomatic microscopic hematuria with risk factors (e.g., smoking, chemical exposure)
• Abnormal urine cytology (atypical or malignant cells)
• Persistent or recurrent microscopic hematuria without proteinuria

👉 In our case: Gross hematuria + smoking history + suspicious bladder lesion → Immediate referral is appropriate.

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📝 What to Include in the Referral

🩺 Basic Clinical Information

• Age, sex, presenting complaint (e.g., “Gross hematuria started 1 day ago”)
• Vital signs and general condition
• Presence or absence of associated symptoms (e.g., fever, pain)

🧪 Completed Workup

• Urinalysis and microscopy (RBC count, morphology, casts)
• Urine culture results (if performed)
• Urine cytology findings (e.g., atypical cells)
• Ultrasound of kidneys/bladder (any mass or hydronephrosis)
• Contrast-enhanced CT (if done)

📄 Risk Factors and Background

• Smoking history (document in pack-years)
• Occupational exposure (dyes, solvents, paints, metals)
• Medication history (e.g., cyclophosphamide, long-term NSAIDs)
• DRE findings: prostate size, nodules, tenderness

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🛠️ Tips Before Referral

• Avoid empirical antibiotics unless infection is clearly suspected
• Do not insert a Foley catheter unless necessary → may obscure cystoscopy findings
• Prepare a clear working hypothesis and convey relevant findings in your referral note

🧠 Remember: The first cystoscopy is often the most informative. Help the urologist by sending a well-prepared case with targeted data.

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🛠️ Practical Tips for History and Examination

✅ How to Strengthen Your Clinical Judgement

• Always clarify: Is it gross or microscopic hematuria?
• Painless gross hematuria in men >50 = bladder cancer until proven otherwise
• Never skip urine microscopy — check RBC morphology, casts, WBCs
• If proteinuria is present with edema or hypertension, think glomerular disease
• Hematuria + flank pain → Think urinary stones
• Hematuria + dysuria + fever → Think UTI or pyelonephritis
• Ask smoking history in pack-years — ≥40 is a critical threshold

⚠️ Common Pitfalls

• Assuming all hematuria is due to infection, especially in young women
• Calling mild proteinuria “nephrotic” without quantification
• Missing transient or benign causes like exercise-induced hematuria
• Overlooking systemic signs in proteinuria (edema, rash, arthralgia)

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💬 Clinical Pearls

“All gross hematuria is bladder cancer until proven otherwise.”
— Common Urology Teaching

“If you see isomorphic RBCs, think urology. If dysmorphic, think nephrology.”
— Internal Medicine Pearls

“The urine is the liquid biopsy of the kidney.”
— Dr. Joseph V. Bonventre, Harvard Medical School

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🗣️ OET Speaking Session – Hematuria

👥 Scenario

You are a doctor in a general practice clinic. A 50-year-old man presents with bright red urine noticed for the first time yesterday. He has no pain, fever, or other symptoms. He is concerned and wants to know what it could be.

Initial urinalysis shows 3+ blood, no protein, and microscopy reveals isomorphic RBCs.

🎯 Your Task

• Explain what hematuria is and the difference between possible causes
• Explore relevant risk factors (e.g., smoking, chemical exposure)
• Discuss the need for imaging and referral to a urologist
• Reassure the patient and provide a plan for follow-up

💬 Sample Statements for Each Task

• Explaining the likely diagnosis:
  “Blood in the urine can come from many different sources, including the kidneys, bladder, or urinary tract. In your case, since it was painless and came on suddenly, we want to rule out anything serious like a tumor, even though it might turn out to be something less concerning.”
• Exploring risk factors:
  “I’d like to ask — do you smoke or have you worked with any industrial chemicals like dyes or paints? These can increase the risk of bladder conditions.”
• Explaining the need for further tests and referral:
  “The urine test shows red blood cells that suggest the bleeding isn’t from the kidneys. I’d recommend imaging and a referral to a urologist who can perform a cystoscopy to look inside the bladder safely.”
• Reassuring and giving next steps:
  “I understand this sounds worrying, but many cases like yours are manageable. We’ve already taken the right first steps. We’ll keep you informed and involved throughout the process.”

💬 Common Patient Cues & Sample Doctor Responses

🧠 Challenging Questions & Sample Doctor Responses

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✉️ OET Writing Task – Sample Referral Letter

20 July 2025

Dr. Laura Bennett
Department of Urology
City Central Hospital

Re: Mr. James Turner, 50 years old

Dear Dr. Bennett,

I am writing to refer Mr. James Turner, a 50-year-old man, for evaluation of painless gross hematuria noted for the first time yesterday. He is otherwise well and reports no associated pain, fever, or constitutional symptoms.

On examination, his vital signs were stable and physical exam was unremarkable, including no costovertebral angle tenderness and normal digital rectal exam. Urinalysis revealed 3+ blood and no protein. Microscopy showed numerous isomorphic red blood cells without casts. Urine cytology returned as “atypical cells – suspicious.” Urine culture was negative.

Renal ultrasound showed no abnormality in the kidneys or ureters, but identified a hypoechoic lesion within the bladder. Contrast-enhanced CT confirmed a T2-enhancing bladder mass suggestive of urothelial carcinoma.

Mr. Turner has a 30 pack-year smoking history and has worked for over 20 years in the industrial painting industry with frequent exposure to solvents. He has no significant past medical history and is not taking any medications currently.

I would appreciate your further assessment and endoscopic evaluation. Please let me know if any additional information is required.

Yours sincerely,

Dr. [Your Name]
General Practitioner

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🧾 Summary – From Urinalysis to Diagnosis

Hematuria and proteinuria may appear as simple urinalysis abnormalities, but they often represent the tip of a diagnostic iceberg.
This article provided a structured, symptom-based approach covering history taking, physical examination, diagnostic workup, and timely referral.

For trainees and OSCE preparation, the most important lesson is to ask:
Is this real? → Where is it coming from? → What is the likely cause?
Combining urinalysis findings with the patient’s age, symptoms, and background allows us to quickly move toward meaningful differentials.

Tomorrow, when a patient says “My test showed blood in my urine,”
you’ll be able to respond not with fear — but with a structured plan.

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🧠 Final Table: Differential Diagnosis by VITAMIN CDE Framework

Category	Possible Causes
V – Vascular	Renal infarction, vasculitis (e.g., ANCA-associated)
I – Infectious	UTI, pyelonephritis, prostatitis, tuberculosis of urinary tract
T – Trauma	Kidney contusion, catheter injury, strenuous exercise
A – Autoimmune	SLE nephritis, IgA nephropathy, Goodpasture syndrome
M – Metabolic	Diabetic nephropathy, nephrotic syndrome, rhabdomyolysis
I – Iatrogenic / Idiopathic	NSAIDs, cyclophosphamide, radiation cystitis, post-biopsy
N – Neoplastic	Bladder cancer, renal cell carcinoma, prostate cancer, myeloma
C – Congenital	Polycystic kidney disease, Alport syndrome, thin basement membrane disease
D – Degenerative	Benign prostatic hyperplasia (BPH)
E – Endocrine / Environmental	Preeclampsia, toxin exposure (e.g., aristolochic acid)

👉 Use this framework not only to expand your differentials, but also to rule out serious conditions early — especially malignancies and glomerular diseases.

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🔗 Related Articles

• 🩸 Hypovolemia – How to Recognize and Differentiate from Dehydration
• 🌡️ Approach to Fever – Distinguishing Infectious and Non-infectious Causes
• 😩 General Fatigue – Depression, Thyroid Dysfunction, or Anemia?
• 🚽 Urinary Symptoms – Frequency, Pain, Retention: A Diagnostic Guide
• 🦵Edema – How to approach edema: peripheral or systemic?
• 🌏 日本語で読む：血尿・蛋白尿の診かた【臨床推論×OSCE対策】

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📚 References

1. Freedman ND, et al. Association Between Smoking and Risk of Bladder Cancer Among Men and Women. JAMA. 2011;306(7):737–745. doi:10.1001/jama.2011.1142
2. Murta-Nascimento C, et al. Smoking and Bladder Cancer in Europe: Dose–Effect Relationship and Interaction with Occupational Exposure. Cancer Causes Control. 2007;18:491–501.
3. Japanese Society of Nephrology. Clinical Practice Guidebook for Kidney Disease 2023. Igakushoin.
4. Japanese Urological Association. Guidelines for the Diagnosis and Treatment of Hematuria 2020. Kanehara Publishing.
5. H. Nagai, et al. Naika Resident no Tessoku (Rules for Internal Medicine Residents) 4th ed. Igakushoin, 2023.

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