Renal

Question 1

Liddle Syndrome

Answer 1

Autosomal dominant condition. Defect in the ENAC channel. Presents early in life with HYPERTENSION, METABOLIC ALKALOSIS, HYPOKALAEMIA.
Ix: Low plasma Renin and Aldo. Genetic testing.
Mx: Amiloride. K replacement.

Question 2

Aparent Mineralocorticoid Excess AME

Answer 2

Deficiency of 11-B-hydroysteroid dehydrogenase enzyme, Usually found in Kidney which converts cortisol into inactive cortisone.
Cortisol binds to MR and acts like aldosterone.
Ix: 24 hour urine cortisol and cortisone

Question 3

Chronic Liquorice Ingestion

Answer 3

Inhibits the enzyme 11-B-HSD2. Causes same issue as in AME.

Question 4

Glucocorticoid Remedial Aldosteronism

Answer 4

Mutation of 11-B-Hydroxylase causes aldosterone synthesis to be under control of ACTH.
Ix: Elevated aldosterone:renin
Mx: glucocorticoid replacement to suppress ACTH

Question 5

Features of hyperaldosteronism

Answer 5

Hypokalaemia and metabolic alkalosis .

Question 6

Bartter Syndrome

Answer 6

Presents in perinatal period or childhood.
Defect in the TAL Na-K-CL transporter, therefore like being born on furosemide.
Hypokalaemia, metabolic alkalosis,

Question 7

Type 1 RTA

Answer 7

Type 1 RTA = Distal defect in H+ excretion.
Hypokalaemia.
Urine Acidic pH >5.5 (due to lack of H+ in urine).
Causes:
- Sjogrens syndrome, SLE, any hypergammaglobuonaemic staes.
Drugs: Lithium, ibuprofen, amphotericin

Question 8

Type 2 RTA

Answer 8

Type 2 RTA = defect in proximal tubule HCO3 reabsorption.
Hypokalaemia
Proximal defect therefore kidney compensates by increasing H+ excretion, very acidic Urine pH <5.5

Question 9

Type 4 RTA

Answer 9

Type 4 RTA = hyporeninaemic hypoaldosteronism, or deminished response to aldosterone.

NAGMA + hyperkalaemia.
Urine pH will be <5.5

Causes: diabetic nephropathy is common, ACE, ARB, MRA, Calcineurin inhibitors, NSAIDS, Trimethoprim.

Question 10

Cause of Type 2 RTA

Answer 10

Myeloma - proximal tubule damage by light chains (may cause fanconi syndrome)
WIlsons Disease
Tenofovir

Question 11

Bartter Syndrome

Answer 11

B before G (therefore TAL)
Often presents in childhood, associated with growth and mental retardation.
Defect in the Na-K-Cl transporter in the TAL.
Like being born on a Loop diuretic.
Hypokalaemic metabolic alkolosis. High urine calcium. Hypocalcaemia.

Question 12

Gittleman Syndrome

Answer 12

G after B (therefore DCT)
Can present in adulthood.
Thiazide. Defect in the Na-Cl transporter in DCT.
Like being born on thiazide.
Hypokalaemic metabolic alkolosis. Hypercalcaemia due to increased Ca reabsorption in TAL.
Hypomagnesiaemia due to down-regulation of Mg transporter.

Question 13

Mimics of Gittleman and Bartter

Answer 13

Differentiate with urinary Cl level:

Vomiting - low urinary Cl due to hypovolaemia and increased NaCl reabsorption.

Diuretic Abuse - variable urinary Cl depending on timing of drug use.

Question 14

Indications for surgical treatment of Primary Hyperparathyroidism?

Answer 14

Age <50 (high risk of future problems if untreated)
Skeletal: Osteoporosis, or vertebral fracture.
Renal: Nephrocalcinosis, nephrolithiasis, EGFR < 60 ml/min. High urinary Ca >10
Serum Ca >0.25 above ULN

Question 15

Side effects of CNIs

Answer 15

Hypertension (ciclo > Tacro)
Diabetes (Tacrolimus > Ciclo)
Cholesterol (C>T)
Neurological Tremor (T>C)
Viral infections (T>C)

Question 16

Side Effects of mTOR inhibitors

Answer 16

Sirolimus, Everolimus

• Impaired wound healing
• Lymphocele inhibitors
• Diabetes
• Proteinuria