Kidneys Lab Questions

Question 1

Some weeks after having a sore throat and high fever, the patient has developed edema. His blood pressure is increased.
Urinalysis:
volume: 450 ml/day
protein: +++ (3 g/day)
sediment: 50–100 erythrocytes/HPF, leukocytes rarely
creatinine clearance: 30 ml/min
What is the presumable diagnosis?

Answer 1

• Urine Volume < 1L/day → Oligouria
• Massive Proteinuria [>3g/day] → Edema
• Creatiine < 120 ml/min→ eGFR↓→ Hypertension
• Sediment > 3 RBCs/HPF → Hematouria
• Diagnosis: Nephritic Syndrome (Hematouria -unique for it)
• Sore throat and Fever indicate that’s caused by Post-streptococcal Glomerulonephritis (Type 3 HSN)

Question 2

Laboratory findings of a patient with massive edemas:
serum total protein: 40 g/l
serum cholesterol: 8 mmol/l
ESR: 28 mm/h
blood pressure: 125/80 mmHg
Urinalysis:
quantity: 1800 ml/day
protein: ++++ (12 g/day)
sediment: 1–2 leukocytes/HPF, erythrocytes rarely, a lot of hyaline casts
What is the presumable diagnosis?

Answer 2

• Serum Protein ↓ [<60g/L] → Edema + ESR↑
• Serum Cholesterol↑ → (Large) LDL is not filtered
• Normal BP, Urine Volume and No Hematuria.
• Massive Proteinuria [>3g/day] → Edema
• Diagnosis: Nephrotic Syndrome - Based on Proteinuria with Edema, Hyperlipidemia.
• Caused by Glomerulonephrosis - Etiologies: Diabetic Nephropathy, SLE, Vasculitis, Infections, Cancer, Multiple Myeloma and Other Cancers, Congenital, Drugs or Amyloidosis / Sarcoidosis

Question 3

A febrile patient complains of lumbar pain.
Urinalysis:
protein: ++
pus: +++
sediment: a lot of leukocytes, some erythrocytes, epithelial cells,
a lot of bacteria, leukocyte casts
Ck: 100 ml/min
ESR: 38 mm/h
What is the presumable diagnosis?

Answer 3

• Pyuria + ESR↑ + Fever + Lumbar Pain → UTI
• RBCs and Epithelials In urine→ Glomerular Damage
• Some Proteinuria [>300mg/day]
• Creatinine [<120ml/min] → Slightly low eGFR
• Leukocyte Casts - WBCs die and shaped Tubularly.
• Diagnosis: Pyelonephritis - Results from an ascending UTI - E.Coli (90% of cases), Klebsiela , Enterococus Faecalis

Question 4

Laboratory findings of a patient include the following:
Urinalysis:
sediment: 3–5 erythrocytes/HPF, rarely leukocytes;
the erythrocytes are isomorphic;
there is a minimal proteinuria;
the urinary protein electrophoresis does not show selectivity in the proteinuria;
Ck: 120 ml/min
What can be the probable diagnosis: glomerular hematuria or urinary tract bleeding?

Answer 4

• Sediment >~ 3 RBC/HPF → ​Microscopic Hematuria
• Normal Morphology (Isomorphic) RBCs in urine → Distal Urinary Tract Bleeding (Not in Tubules)
• “No selectivity in Proteinuria” → No filtration barrier involvment
• Normal Creatnine Clearance → Normal GFR
• Diagnosis: Mild Urinary Tract Bleeding (Probably from Nephrolithiasis)

Question 5

After receiving a massive dose of aminoglycoside antibiotic, a patient with no prior symptoms of kidney disease develops a body weight gain of 3 kg over a period of 3 days. He does not void urine spontaneously. The total volume of urine collected by catheterization is 200 ml/day. Other laboratory results:
serum creatinine: 440 μmol/l
serum urea: 28.5 mmol/l
plasma K+: 6.2 mmol/l
What is the most likely diagnosis?

Answer 5

• Aminoglycosides Nephrotoxicity → Tubular Damage
• Urine Volume<200ml/ day → Anuria
• Water Retention→Weight Gain
• Serum Creatinine↑ and Serum Urea↑ → BUN↑
• K+ > 5 mM → Hyperkalemia
• Diagnosis: Acute Renal Failure due to Aminoglycosides Toxicity

Question 6

The serum glucose level is 15 mmol/l in a diabetic ketoacidosis. GFR is markedly decreased (20 ml/min). Tubular function tests are negative. No glucose can be detected in the urine (by repeated tests).
How is this possible?

Answer 6

• Normally, glucose is reabsorbed (in PCT mostly) up until it reached the Blood glucose level of 10mM at which point the SGLT transporters are Saturated
• In this Case: the GFR is so low that gulcose has time to be reabsorbed in the Unsaturated SGLT2 (Not damaged)

Question 7

Laboratory findings of a patient:
Urinalysis:
color: straw-yellow pus: +++
transparency: turbid (nubecula) blood: +
quantity: 400 ml (present), glucose: neg
1600 ml/day acetone: neg
specific gravity: 1022 ubg: norm
protein: 50 mg/day bilirubin: neg
Urinary sediment:
20–30 epithelial cells, 30–40 WBC, 3–4 RBC, per high power field
Further data:
body temperature: 38°C, WBC: 12 G/l, RBC: 4.5 T/l, ESR:2 mm/h
creatinine clearance: 120 ml/min, cultivation of E. coli: positive
What is the most likely diagnosis?

Answer 7

• No signs of Systemic Infection - ESR normal and No fever
• Microscopic Hematuria, Pyuria, WBC↑, E.Coli+
• Diagnosis: UTI from E.coli that has not ascended to become pyelonephritis