Paediatric renal problems Flashcards
What is a common antenatal presentation of renal disease?
Renal Pelvis dilatation
What are possible signs of the abnormal kidney (visible on investigations)?
– Echo bright
– Small
– Cystic
– Wrong place
What si clinical significance of renal congenital malformation? (3)
- infections -> may cause renal damage
- renal function (creatinine, BP, proteinuria)
- growth and development
What’s that?
Cystic kidney disease
What’s CAKUT?
congenital anomalies of the kidney and urinary tract
What is a characteristic feature of renal hypodysplasia?
Renal hypodysplasia
- small kidneys with a reduced number of nephrons and dysplastic features
What’s renal aplasia?
Renal aplasia (agenesis) – Congenital absence of kidney(s)
What’s congenital renal hypoplasia?
Congenitally small kidneys with a reduced number of nephrons but normal architecture
What’s renal dysplasia?
Renal dysplasia
- the presence of malformed renal tissue elements, including primitive tubules, interstitial fibrosis, and/or the presence of cartilage in the renal parenchyma
- dysplastic kidneys often contain cysts
What the birth weight tends to be in patients with congenital renal abnormalities?
The birth weight (BW) is often below the normal mean because of the association with intrauterine growth restriction (IUGR)
Possible presentaiton of congenital renal abnormalities in neonate
In the neonatal period, patients may present with one or more of the following:
●Pneumothorax
●Feeding difficulties
●Metabolic acidosis
●Urinary sodium losses
●Impaired renal function based on elevated serum/plasma creatinine level
Possible presentation of congenital renal disease in first year of life
- anorexia
- vomiting
- failure to thrive
What’s possibl presentation of congenital renal disease ater 1st year of life
- proteinuria
- possible polyuria nad polydypsia
- failure to grow
- anaemia
- osteodystrophy (secondary to hyperparathyroidism - as PTH tries to compensate for low Ca++ reabsorption at the tubules)
What renal abnormalities (in general) would indicate poor renal prognosis?
Patients with malformations involving a reduction in kidney numbers or size are most likely to have a poor renal prognosis
Causes of CAKUT
- genetic abnormalities - mutations in some genes and syndromes
- environmental factors -> malnutrition, exposure to teratogenic drugs
- deficiency of vitamin A (will interfere with kidney development)
What do we need to monitor in unilateral kidney problems?
Follow-up care
- the contralateral normal kidney is expected to undergo compensatory hypertrophy in patients with unilateral renal problems (e.g. renal agenesis)
- serial ultrasonography is recommended to monitor for renal compensatory growth
If there is no compensatory hypertrophy (of normal functioning kidney), what further tests do we need to do?
- If compensatory hypertrophy is not observed -> ongoing monitoring of the patient is recommended -> yearly assessment of blood pressure and urinalysis
What tests are recommended in patient with elevated BP and proteinuria?
In patients with elevated blood pressure or urinary protein excretion -> renal function should be assessed by obtaining a serum creatinine to estimate the GFR
Disruption of the normal embryologic migration of the kidneys may result in what conditions? (2)
- renal ectopia (eg, pelvic kidney)
- fusion anomalies (eg, horseshoe kidney)
What’s vesicoureteral reflux?
Vesicoureteric reflux (VUR)
- abnormal backflow of urine from the bladder into the ureter and kidney
- relatively common abnormality of the urinary tract
- predisposes to urinary tract infection (UTI)
- found in around 30% of children who present with a UTI
- complications: 35% of children develop renal scarring it is important to investigate for VUR in children following a UTI
A child presents with UTI, what do we need to investigate for?
Vesicoureteric reflux (VUR)
- abnormal backflow of urine from the bladder into the ureter and kidney
- relatively common abnormality of the urinary tract
- predisposes to urinary tract infection (UTI)
- found in around 30% of children who present with a UTI
- complications: 35% of children develop renal scarring it is important to investigate for VUR in children following a UTI
Pathophysiology of Vesicoureteric reflux
Pathophysiology of VUR
- ureters are displaced laterally, entering the bladder in a more perpendicular fashion than at an angle
- therefore shortened intramural course of ureter
- vesicoureteric junction cannot therefore function adequately
Investigations in Vesico-ureteral reflux
Investigation
- VUR is normally diagnosed following a micturating cystourethrogram
- a DMSA scan* may also be performed to look for renal scarring
*DMSA scan = radionuclide scan to assess renal morphology
What ‘big’ kidney on USS may indicate?
Polycystic kidney disease - kidney is filled with cysts/ above the centile that is expected for a child at given age
DMSA test - what is it done for?
Injection of the die - to look at each kidney’s uptake of it and their shape
MSUG test - what is it done for?
Dye is injected into the bladder through the catheter - to see if there is any backflow into the urinary tract
* normally bladder should be able to hold the dye, but if dye goes up through the urethra -> abnormal (posterior-ureteral valve)
*post-dilatation seen + abnormally shaped bladder (bumpy rather than smooth)
What’s the diagnosis?
What happens/ how kidney would be damaged?
Vesicoureteric Reflux
Dye is backflowing to the ureters and kidney = so we assume urine is doing the same -> infections -> renal scarring
What’s wrong with left ureter?
It is dilated
What’s the abnormality?
Dye uptake is asymmetrical - problem with one of the kidneys
A clinical trial of Nephrotic syndrome
- proteinuria
- low albumin
- oedema
What is the most common cause of nephrotic syndrome?
What do we treat it with?
- Idiopathic nephrotic syndrome*
- treat with steroids -> usually for minimum 8 weeks
How do we measure proteinuria on the urinalysis?
What is parental advice after we discharge a child home after nephrotic syndrome?
To do urinalysis daily, to measure the protein - in order to treat before they get oedema again
Triad of Nephritic syndrome
- haematuria (visible or on dipstick)
- hypertension
- high creatinine
What’s the common cause of nephritis?
Henoch Schonlein Purpura
- type of vasculitis -> inflamed blood vessels
*characteristic rash
* self-limiting course -> but may cause long lasting kidney damage
What’s Henoch Schonlein Purpura?
Henoch-Schonlein purpura (HSP)
- an IgA mediated small vessel vasculitis
- HSP is usually seen in children following an infection
Features of Henoch Schonlein Purpura
- palpable purpuric rash (with localized oedema) over buttocks and extensor surfaces of arms and legs
- abdominal pain
- polyarthritis
- features of IgA nephropathy may occur e.g. haematuria, renal failure
Treatment and prognosis for Henoch Schonlein Purpura
Treatment
- analgesia for arthralgia
- treatment of nephropathy is generally supportive. There is inconsistent evidence for the use of steroids and immunosuppressants
Prognosis
- usually excellent, HSP is a self-limiting condition, especially in children without renal involvement
- around 1/3rd of patients have a relapse
Stages of CKD
What is the minimum height and weight for a child to be able to ‘fit’ transplanted adult kidney?
10-12 kg
90 cm
*renal dietician needed to help a child grow to the point when they can have a transplant
What’s the 1st line of dialysis in younger children?
Peritoneal dialysis
- this is because there is no need to use their blood vessels (like in haemodialysis)
How does peritoneal dialysis work?
- can be given overnight (8-12 hours) - 10 cycles of dialysis each night done while a child asleep
- Dextrose fluid concentration - removes fluid by osmotic force (via peritoneal membrane)
What’s that?
This child has extra feeds via NG tube
What children is haemodialysis usually done in?
Over 10 kg
(this is for the circulation to cope well enough)
What’s that?
Haemodialysis
Typical location of renal transplant
R iliac fossa -> as transplant is usually implanted into iliac vessel
*on the picture an adult kidney is inserted into a child - massive amount of space taken - therefore a child need to be a certain weight to cope with it and enable the surgical wound clousure
Where in the kidney do these diuretics work?
- thiazide
- potassium sparing
- Thiazide - DCT
- Potassium-sparing - collecting duct
Clinical presentation of a patient with Proximal Renal Tubule problem
Problems due to tubules not being able to reabsorb the substances -> lost in the urine
- acidosis -> biocarb are lost
- aminoaciduria -> amino-acid loss
- phosphoturia -> phosphate loss
- glycosuria -> gluose loss
- low molecular weight proteinuria
What is cystinosis?
Inherited disorder -> cystine deposits within proximal renal tubule
- failure to thrive
- features of proximal renal tubule problems -> different electrolyte imbalance
What is a syndrome that may cause problems in Loop of Henle?
Batter’s syndrome
- mimics the effect of Furosemide
- severe dehydration
- loss of potassium in the urine
- hyponatraemia due to dehydration
- failure to thrive
-
Gitelman’s syndrome
- what part of the kidney is affected?
Gitelman’s syndrome = Distal Tubule Disorder -> mimics Thiazide diuretic effects
- relatively mild in effects
- low magnesium (as distal tubules have a role in Mg+ regulation)
- dehydration may also be present -> due to water loss
(3) disorders (names) that occur within the collecting duct
- Pseudohypoaldosteronism
- Liddle’s Syndrome
- Nephrogenic Diabetes Insipidus
What electrolyte abnormality would Pseudohypoaldosteronism present with?
Pseudohypoaldosteronism
- salt wasting
- high K+
*disorder in collecting duct
What electrolyte abnormality is seen in Liddle’s syndrome?
Liddle’s syndrome
- hypertension
- low K+
* disorder in collecting duct
What happens to the urine in nephrogenic diabetes insipidus?
Urine is dilute (not able to be concentrated)
