Renal

Question 1

What is oedema

Answer 1

Defined as an increase in interstitial fluid

Question 2

In a clinical setting what causes oedema?

Answer 2

“swelling”, pitting oedema, facial puffiness, ascites, pleural effusions, pulmonary oedema

Question 3

What are some causes of increased interstitial fluid

Answer 3

• Obstruction of lymphatic drainage
• Obstruction of venous drainage
• Lowered oncotic pressure
• Salt and water retention
  Venous obstruction (venous thrombosis)
  Lymphoedema - congenital or blockage

Question 4

What causes of lowered oncotic pressure and what does it cause?

Answer 4

Low albumin/ protein
Malnutrition
Decreased production:
Liver
Increased loss:
Gut
Kidney- nephrotic syndrome

Question 5

What causes increased Salt and Water retention

Answer 5

Kidney – impaired GFR

Heart failure

Question 6

3 year old boy referred by GP with a 3 days history facial swelling, abdominal swelling. Treated for allergy. Passing foaming urine. Well in himself. Recent cold 10 days ago. No PMHx. No FHx.

Useful findings
Differential diagnosis
Initial investigation
Initial management

Question 7

3 Key features of Nephrotic syndrome

Answer 7

Heavy proteinuria
Hypoalbunaemia
Oedema

Question 8

What do we have in nephrotic syndrome

Answer 8

Podocytes

Question 9

What does quantitative heavy proteinuria look like?

Answer 9

First morning urine protein:creatinine

Normal < 20 mg/mmol
No definite level that is nephrotic

BUT > 600 mg/mmol likely to produce hypoalbuminaemia BUT occurs at lower levels

Question 10

Semin- quantitative proteinuria

Answer 10

Negative 0 mg/dL
trace 15-30
1+ 30-100
2+ 100-300
3+ 300-1000
4+ >1000

Question 11

Hypalbuminaemia features

Answer 11

Normal range ~ 35 – 45 g/l
Fluid retention & oedema usually with albumin < 25 – 30 g/l but not strict cut off
Serum albumin linked to fluid retention

Other protein losses responsible for other complications eg infection, thrombosis

Question 12

What are the 3 types of nephrotic syndrome?

Answer 12

Congenital NS (<1 year)
Steroid sensitive NS
Steroid resistant NS

Question 13

Features of steroid sensitive NS

Answer 13

Normal BP
No macroscopic haematuria
Normal renal function
No features to suggest nephritis
Respond to steroids
Histology – “minimal change” usually

Question 14

Features of steroid resistant NS

Answer 14

Elevated BP
Haematuria
May be impaired renal function
Features may suggest nephritis
Failure to respond to steroids
Histology – various, underlying glomerulopathy, basement membrane abnormality

Question 15

S + S of Steroid sensitive NS

Answer 15

Peak age of onset 2 – 5 yrs
M > F
Higher incidence in those from Asian sub-continent
? Immunological aetiology
Recurrent relapses
~ 5% continue into adult life
Normal renal function if steroid responsive

Question 16

Treatment for SSNS

Answer 16

Standard course of prednisolone for first episode:
60mg/m2 for 4 weeks
40mg/m2 on alternate days for 4 weeks

Other considerations:
Na & water moderation
Diuretics
Pen V
Measles & varicella immunity & pneumococcal immunisation

Question 17

Features of acute glomerulonephritis

Answer 17

Haematuria – often macroscopic
Proteinuria – varying degree

Impaired GFR – rising creatinine, variable degree

Salt and water retention – hypertension, oedema

Question 18

Features of acute post-streptococcal glomerulonephritis

Answer 18

Nasopharyngeal or skin infection
Gp A β haemolytic streptococcus, “nephritogenic” strains

Antigen-antibody complexes in glomerulus, complement activation

Clinical nephritis 10 days post infection
Haematuria, swelling, decreased urine output

Oedema, hypertension, signs of cardiovascular overload

Question 19

3 types of AKI

Answer 19

Pre- renal

Renal

Post renal

Question 20

IN RAAS Aldosterone is released by angiotensin II which also causes increased BP - what does this cause

Answer 20

Salt and Water retention

Question 21

Management of acute post-streptococcal glomerulonephritis

Answer 21

Fluid balance – measurement of input/output, fluid moderation, diuretics, salt restriction
Correction of other imbalances – potassium, acidosis
Dialysis - if needed (uncommon)
Penicillin - treatment of streptococcal infection

Question 22

Prognosis of Acute post-streptococcal glomerulonephritis

Answer 22

95% full recovery
Not recurrent
No long term implication for renal function if full recovery

Question 23

Investigations for Acute post-streptococcal glomerulonephritis

Answer 23

FBC – mild normochromic, normocytic anaemia

U&Es – increased urea and creatinine, (hyperkalaemia, acidosis)
Immunology – raised ASOT/antiDNAse B titre, low C3, C4
Throat /other swabs
Urinalysis

Haematuria – usually macroscopic

Proteinuria – dipstick, protein:creatinine

Microscopy – RBC cast

Question 24

What is Henoch-Scholein Purpura (HSP)

Answer 24

Vasculitis
Affects
Skin
Joints
Gut
Kidneys

Question 25

Features of HSP nephritis

Answer 25

IgA deposition Variable renal presentation: haematuria/proteinuria nephrotic syndrome acute nephritis renal impairment hypertension If nephrotic are steroid resistant, may need alternative immunosuppression and/or other anti-proteinuric measures Variable prognosis, may be ESRD

Question 26

What is the definition of a UTI?

Answer 26

Growth of bacteria within the urinary tract - (105 organisms/ml grown on culture of appropriate sample)  Acute pyelonephritis ie upper tract UTI Acute cystitis ie lower tract UTI

Question 27

Why are finding UTIs in children important

Answer 27

3-5% of girls & 1-2% of boys Can cause significant acute illness 50% rate of reoccurrence 50% have structural abnormality – presenting symptom Long term complication : kidney scarring – hypertension – CKD Heavy burden on the NHS and families

Question 28

When should we suspect UTI in infants younger than 3 months?

Answer 28

Fever Vomiting Lethargy Irritability Poor feeding Failure to thrive Abdominal pain Jaundice Haematuria Offensive urine

Question 29

When should we suspect UTI in preverbal children older than 3 months?

Answer 29

Fever Abdominal pain Loin tenderness Vomiting Poor feeding Lethargy Irritability Haematuria Offensive urine Failure to thrive

Question 30

When should you suspect UTI in verbal children over 3 months?

Answer 30

Frequency Dysuria Dysfunctional voiding Changes to continence Abdominal pain Loin tenderness Fever Malaise Vomiting Haematuria Offensive urine Cloudy urine

Question 31

When do we need a urine sample?

Answer 31

with symptoms and signs of UTI (from table above) with unexplained fever of 38°C or higher with an alternative site of infection but who remain unwell All infants younger than 3 months with suspected UTI should be referred to paediatric specialist care and a urine should be sent for urgent microscopy and culture

Question 32

How do we collect a urine sample?

Answer 32

MSU clean catch - recommended method urine collection pads catheter samples or suprapubic aspiration (SPA) Before SPA is attempted, ultrasound guidance should be used to demonstrate the presence of urine in the bladder. Do not delay treatment in seriously ill infants

Question 33

How should we analyse urine?

Answer 33

Visual inspection Dipstick Nitrites Leucocyte esterase M,C & S

Question 34

Microscopy results

Answer 34

Bacteria Pos Pyuria Pos: UTI Bacteria Neg Pyuria Pos: Antibiotic treatment should only be started if clinically UTI (Could be partially treated UTI Bacteria Pos Pyuria Neg: UTI Bac neg Pyuria neg: No UTI

Question 35

How do we interpret results for a UTI?

Answer 35

105 organisms/ml of single bacteria on a CCU/MSU is the bacteriological criterion for UTI Diagnosis Any growth on a SPA is considered significant E. coli – most common bacteria Proteus – more common in boys Pseudomonas – may indicate structural abnormality

Question 36

When do children need admission?

Answer 36

< 3months Systemically unwell Significant risk factors

Question 37

How do we treat Infants younger than 3 months with a UTI

Answer 37

Minimum 2-4 Days IV antibiotics followed by oral

Question 38

How do we treat Systemically wellChildren with no systemic features and absence of significant fever

Answer 38

Treat with 3 days oral antibiotics. Advised to return if no better at 24-48hrs for reassessment

Question 39

How do we treat Systemically Unwell (Fever > 38 +/- loin pain / tenderness

Answer 39

Treat with 7-10 days oral antibiotics (Consider IV antibiotics according to clinical judgement. Use lower threshold for IV antibiotics in younger children, those with significant risk factors and severely ill.)

Question 40

What are the features of Atypical UTI

Answer 40

Septicaemia/ requires IV antibiotics Non-E.coli UTI Poor urine flow Abdominal mass/ bladder mass Raised creatinine Failure to respond to treatment with suitable antibiotics within 48hrs

Question 41

What are the features of recurrent UTI

Answer 41

Two or more UTI episodes at least one episode with systemic symptoms or signs Three or more UTI’s without systemic symptoms/ signs

Question 42

Investigation of UTI

Answer 42

ULTRASOUND RENAL TRACT - Non – invasive - Observer dependent - Size and drainage of kidneys & bladder - Good for ? obstruction Micturating cystourethrogram - Vesicoureteric reflux - Bladder - Posterior urethra DMSA scan Radionuclide imaging Dimercaptosuccinic acid (DMSA) scan  Relative renal function Renal “scarring

Question 43

What is the Vesicoureteric reflux

Answer 43

Retrograde flow of urine from bladder into ureter/ pelvicalyceal system/intrarenal Severity graded on level of reflux and associated dilatation, clubbing Associated with UTI, renal abnormality