Renal Histopath

Question 1

Triad of nephrotic syndrome

Answer 1

Proteinuria > 3g/ day Oedema (also have dys/hyperlipidaemia (liver)) Hypoalbuminaemia

Question 2

Nephrotic syndrome oedema pattern (1)

Answer 2

Starts peri orbitally

Question 3

Minimal change disease: epidemiology, Light micrscopy (1), Electron microscopy (1), immunofluorescence (1), response to steroids (1), Prognosis (1)

Answer 3

Most common in children - 75% rest elderly

no changes on light microscopy

Electron microscopy - loss of podycyte foot processes

IF - no deposits

Response to steroids - 90% Prognosis -<5% ESRF

Question 4

Membranous glomerular disease: epidemiology, Light micrscopy (1), Electron microscopy (2), immunofluorescence (2), response to steroids (1), Prognosis (1)

Answer 4

Common in adults

Diffuse GBM thickening

EM - loss of podocyte foot processes, subepithelial deposits (spikey)

IF - Ig & complement in granular deposits along GBM

Poor response to steroids 40% get ESRF after 2-20 yrs

Question 5

Focal segmental glomerulonephritis: epidemiology, Light micrscopy (3), Electron microscopy (1), immunofluorescence (2), response to steroids (1), Prognosis (1)

Answer 5

Common in afro-carribean

LM - Focal & segmental glomerular consolidation + scarring, + hyalinosis (change in tissue to less functional/lower form)

EM - loss of podocyte foot processes

IF - Ab + complement in SCARRED areas 50% respond to steroids 50% ESRF in 10 yrs can be secondary to obesity HIV nephropathy

Question 6

What are secondary causes of nephrotic syndrome? (2)

Answer 6

Diabetes

Amyloidosis

Question 7

Nephrotic syndrome secondary to diabetes: histology (2)

Answer 7

Diffuse GBM thickening

Mesangial matrix nodules - KIMMELSTIEL WILSON NODULES (usually asian)

Question 8

Nephrotic syndrome secondary to amyloidosis: histology (1)

Answer 8

APPLE GREEN BIREFRINGENCE with CONGO red stain

Question 9

Nephrotic syndrome secondary to amyloidosis: + hints in question (6)

Answer 9

May have chronic inflammation: RA

May have chronic infection: TB - causes AA protein deposition

May have Ig light chain deposition from multiple myeloma (AL protein deposition)

Clinical clues for amyloidosis - Macroglossia, HF, hepatomegaly

Question 10

Pathology of acute tubular injury (ATI)/ ATN (4) (the most common cause for ARF)

Answer 10

Damage to tubular epithelial cells Blockage of tubules by casts Reduced flow + haemodynamic changes ARF

Question 11

Causes of ATN (5)

Answer 11

Ischaemia - burns, septicaemia Nephrotoxins - drugs (NSAIDs, gentamicin), radiographic contrast agents, heavy metals, myoglobins

Question 12

Histopathology of ATN (1)

Answer 12

necrosis of short segments of tubules

Question 13

Acute pyelonephritis: most common causative pathogen (1) Presentation (8), What is seen in urine (1)

Answer 13

Bacterial infection of kidney due to ascending infection by E. coli. Presentation: fevers, chills, flank pain, renal angle tenderness, dysuria, haematuria Leukocytic casts are seen in urine

Question 14

Chronic pyelonephritis & reflux nephropathy: what is it? Causes (3)

Answer 14

Inflammation + scarring of the parenchyma due to recurrent & persistent bacterial infection Causes: obstruction - posterior urethral valves, renal calculi Urine reflux - reflux nephropathy

Question 15

What is acute interstitial nephritis?

Answer 15

A hypersensitivity rxn, usually to a drug (abx, NSAIDS) Usually begins days post exposure

Question 16

Acute interstitial nephritis presentation (5)

Answer 16

Eosinophilia, haematuria, fever, skin rash, proteinuria

Question 17

Chronic interstitial nephritis/ analgesic nephropathy, cause (1) & symptoms (4)

Answer 17

Usually in elderly due to chronic use of NSAIDs symptoms (occur late in disease): haematuria, proteinuria, HTN, anaemia

Question 18

What is ARF?

Answer 18

Rapid loss of renal function manifesting as increased Urea & creatinine

Question 19

Pre-renal causes of ARF ( 3) (most common cause of ARF)

Answer 19

Renal hypo perfusion - sepsis, hypovolaemia, burns, renal artery stenosis, acute pancreatitis

Question 20

Renal causes of ARF (3)

Answer 20

ATN - most common renal cause Acute GN thrombotic microangiopathy

Question 21

Post renal causes of ARF (4)

Answer 21

Obstruction - stones, tumours, prostatic hypertrophy, retroperitoneal fibrosis

Question 22

What is CRF?

Answer 22

Progressive, irreversible loss of renal function + symptoms of uremia - itching, anorexia, fatigue & confusion if severe

Question 23

Commonest causes of CRF in UK (5) (in order)

Answer 23

Diabetes GN HTN Reflux nephropathy Polycystic kidneys

Question 24

5 Stages of CRF

Answer 24

Stage 1 - kidney damage + normal renal function (proteinuria may be there) GFR > 90 Stage 2- mildy impaired; GFR 60-89 Stage 3 - moderately impaired; GFR 30-59 Stage 4 - severely impaired; GFR 15-29 Stage 5 - renal failure

Question 25

Inheritance of adult polycystic kidney disease (2)

Answer 25

Autosomal dominant 85% due to PKD1 mutation on Cr 16 - encodes polycystin1 15% due to PKD 2 mutation on Cr 4- encodes polycystin2

Question 26

Pathological features of PKD (3)

Answer 26

Large multicystic kidneys with destroyed renal parenchyma Liver cysts (in PKD1) Berry aneurysms

Question 27

Clinical features of PKD (3)

Answer 27

Haematuria, flank pain, UTI clin features due to cyst complications e.g. rupture/infection/ haemorrhage

Question 28

Lupus nephritis infor card

Answer 28

depending on site & intensity of IC depostion clinical presentation may be: just urinary abnormalities, nephrotic syndrome, ARF, CRF

Question 29

6 Classes of Lupus nephritis: give 1-3

Answer 29

1 - minimal mesangial lupus nephritis - ICs but no structural damage 2 - mesangial proliferative lupus nephritis - ICs + mild increase in mesangial cellularity 3 - focal lupus nephritis - active swelling + proliferation in less than half the glomeruli

Question 30

Class 4-6 of lupus nephritis

Answer 30

Class IV - diffuse lupus nephritis - more than half glomeruli involved Class V - membranous lupus nephritis - subepithelial IC deposition Class VI - advanced sclerosing - complete sclerosis of > 90% of the glomeruli