Passmed nephrology

Question 1

What is acute interstitial nephritis?

Answer 1

Hypersensitivity reaction causing inflammation of the space between the cells and the tubules of the kidney

Question 2

What causes interstitial nephritis?

Answer 2

Drugs: Penicillin, Rifampicin, NSAIDS, Allopurinol, Furosemide
Systemic disease: SLE, Sarcoidosis, Sjorgens
Infection: Hanta virus, Staphylococci

Question 3

Features of Interstitial Nephritis?

Answer 3

Fever, rash, arthralgia
Eosinophilia
Mild renal impairment
HTN

Question 4

What investigations for interstitial nephritis?

Answer 4

MSU (sterile pyuria & white cell casts)

Question 5

What is the treatment for acute interstitial nephritis?

Answer 5

Steroids for the inflammation

Question 6

AKD vs. CKD?

Answer 6

CKD has bilaterally small kidneys
CKD presents with Hypocalcemia

Question 7

Where is vitamin D activated?

Answer 7

Kidneys

Question 8

What causes enlarged kidneys despite CKD?

Answer 8

SHAPE

Scleroderma
HIV-associated nephropathy
Amyloidosis
Polycystic kidney disease
Endocrine: Diabetic nephropathy (early stages)

Question 9

What are the causes of AKI?

Answer 9

Prerenal: HF, Dehydration, Renal artery stenosis
Intrinsic: Glomerulonephritis, ATN, AIN, Rhabdomyolysis, Tumour lysis syndrome
Postrenal: BPH, Kidney stone, External compression of ureter

Question 10

What are the indications of dialysis in AKI?

Answer 10

A acidosis (ph<7.1]
E electrolyte derangement (refractory hyperkalaemia)
I intoxication/ingestion (alcohol/salicylates/lithium)
O overload of fluid (congestive cardiac failure)
U uraemia (uraemia pericarditis or encephalopathy)

Question 11

What drugs to stop in AKI?

Answer 11

Stop the DAAMN Drugs

Diuretics
ACEi
ARBs
Metformin
NSAIDs

Question 12

What are the AKI stages?

Answer 12

1 Increase 1.5-1.9x baseline OR < 0.5ml/kg/h for >6 consecutive hours
2 Increase 2.0-2.9x baseline OR < 0.5ml/kg/h for >12 consecutive hours
3 Increase > 3x baseline or >354 µmol/L OR < 0.3ml/kg/h for > 24h or anuric for 12h

Question 13

What would a urine dipstick with proteinuria indicate in an AKI?

Answer 13

The urine dip shows proteinuria which would only be present with an intrinsic renal AKI

Question 14

Can aspirin be continued in an AKI?

Answer 14

Aspirin at a cardioprotective dose (75mg) can be continued as it will not negatively impact renal function.

Question 15

What are the features of AKI?

Answer 15

Most patients usually asymptomatic but as renal failure progresses the following may be seen:

reduced urine output
pulmonary and peripheral oedema
arrhythmias (secondary to changes in potassium and acid-base balance)
features of uraemia (for example, pericarditis or encephalopathy)

Question 16

What is the difference in sodium aspects between prerenal uraemia vs. ATN

Answer 16

In prerenal uraemia, the body is trying to retain fluids. Hence, it is going to retain sodium to increase them, resulting in high blood sodium and low urine sodium.

Question 16

When to refer to nephrologist in AKI?

Answer 16

Renal tranplant
ITU patient with unknown cause of AKI
Vasculitis/ glomerulonephritis/ tubulointerstitial nephritis/ myeloma
AKI with no known cause
Inadequate response to treatment
Complications of AKI
Stage 3 AKI (see guideline for details)
CKD stage 4 or 5
Qualify for renal replacement hyperkalaemia / metabolic acidosis/ complications of uraemia/ fluid overload (pulmonary oedema)

Question 17

What is the diagnostic criteria for AKI?

Answer 17

Rise in creatinine of 26µmol/L or more in 48 hours OR
>= 50% rise in creatinine over 7 days OR
Fall in urine output to < 0.5ml/kg/hour for more than 6 hours in adults (8 hours in children) OR
>= 25% fall in eGFR in children / young adults in 7 days.

Question 18

What is the difference between ADPKD1 vs ADPKD2

Answer 18

ADPKD 1: 85%, chromosome 16, presents with renal failure earlier
ADPKD 2: 15%, chromosome 4

Question 19

What is the diagnostic criteria in ADPKD?

Answer 19

Ultrasound diagnostic criteria (in patients with positive family history)
two cysts, unilateral or bilateral, if aged < 30 years
two cysts in both kidneys if aged 30-59 years
four cysts in both kidneys if aged > 60 years

Question 20

What is the management for ADPKD?

Answer 20

Tolvaptan. Tolvaptan is a selective vasopressin antagonist. By inhibiting the binding of vasopressin to the V2 receptors, tolvaptan reduces cell proliferation, cyst formation and fluid excretion

Question 21

What are the features of ADPKD?

Answer 21

hypertension
recurrent UTIs
flank pain
haematuria
palpable kidneys
renal impairment
renal stones

Question 22

What are the extra-renal manifestations of ADPKD?

Answer 22

liver cysts (70% - the commonest extra-renal manifestation): may cause hepatomegaly
berry aneurysms (8%): rupture can cause subarachnoid haemorrhage
cardiovascular system: mitral valve prolapse, mitral/tricuspid incompetence, aortic root dilation, aortic dissection
cysts in other organs: pancreas, spleen; very rarely: thyroid, oesophagus, ovary