Nephrology

Question 1

Discuss the management of hypernatremia

Answer 1

Oral free water intake

- 2mL/kg/hr of D5W increase Na by 12mEq/d

Question 2

What are the characteristic ECG changes for hypokalemia

Answer 2

• flattened or inverted T wave
• u wave
• ST depression
• prolonged QT interval
• severe: prolonged PR, wide QRS, heart block

Question 3

Differentiate between nephrotic and nephritic syndrome

Answer 3

Nephrotic (associated with glomerular disease):
- proteinuria >40mg/m2/hr of albumin with 3+ urine dipstick
- edema
- hypoalbuminemia
- albuminuria
- hypercholesterolemia 
Nephritic:
- hematuria, gross 3+ on dipstick
- mild proteinuria <40
- hypertension
- azotemia

Question 4

List the differential for proteinuria

Answer 4

Non-nephrotic range (<40, glomerual or tubular)
- postural proteinuria, secondary proteinuria
Nephrotic range
- minimal change nephrotic syndrome
- focal segmental glomerulosclerosis
- rare: IgA nephropathy, membrane glomerulonephropathy, membranoproliferative glomerulonephropathy

Question 5

List the differential for hematuria

Answer 5

Vascular: renal vein thrombosis
Glomerular: post-streptococcal glomerulonephritis, henoch-schonlein purpura, IgA nephropathy
Tubulointerstitial: ATN, tubulointerstitial nephritis, polycystic kidney disease
Lower urinary tract: calculi, neoplasm, foreign body, trauma

Question 6

Discuss the presentation and management of minimal change nephrotic syndrome

Answer 6

Demographics: 
- 2-6, Caucasian, Indian
Pathophysiology: 
- primary unknown
- secondary is rare and due to malignancy, infection, or collagen vascular disease
Presentation: 
- edema, possible pulmonary edema, 
Investigations: 
- proteinuria
- microscopic hematuria
- low albumin
- high cholesterol
- no evidence of renal pathology on biopsy 
Treatment: 
- 1st line is prednisone 60mg/m2/day divided TID for 6 weeks and then 40mg/m2/day divided q2 days for 6 weeks
- parents due daily urinalysis dipstick and have constant follow up for blood pressure and weight

Question 7

List some of the complications of minimal change disease

Answer 7

Hypovolemia
Infection
- immune suppressive therapy plus loss of IgG increase risk of infection
- require broad spectrum antibiotics if infection is suspected or acyclovir and IVIG for VZV
Thrombosis
- decrease in intravascular volume and renal loss of anti-coagulant factors (anti-thrombin 3, protein C and S)
Hypercholesterolemia

Question 8

Discuss the diagnosis and management of Post-streptococcal glomerulonephritis

Answer 8

Pathophysiology
- develop cross reactant antibodies against glomerular membrane
Presentation: 
- nephritic syndrome
- no proteinuria after 6 months and no hematuria after 12 months
Investigations: 
- high anti-streptococcal antibody titres
- low C3
- high creatine, high BUN
Treatment: 
- penicillin for strep infection
- address complications of AKI

Question 9

Discuss the presentation and management of IgA nephropathy

Answer 9

Presentation: 
- gross hematuria following inciting event such as URTI or vaccine, 
- nephritic syndrome
Investigations: 
- tests to rule out other causes of nephritic syndrome (SLE, post-strep, kidney stone), 
- high IgA levels
- diagnosis with kidney biopsy
Treatment:
- hypertension with ACEi or ARB
- systemic steroid
- hypercholesterolemia with statin

Question 10

What is postural proteinuria?

Answer 10

Epidemiology: Present in adolescent females

• Have increased protein release during the day when upright, which decreases overnight
• Benign disorder that disappears with age
• <0.5g/day of protein lost

Question 11

Discuss the red flags for minimal change disease requiring further evaluation with renal biopsy

Answer 11

Age <1
Age > 12 (membranous or SLE more likely)
Black (SLE)
Renal failure
Macro or microhematuria
No response within 4 weeks of initiating high dose steroids