Nephrology Flashcards
Define nephrotic syndrome
Glomerular disorder Presents with triad of - generalised oedema - heavy proteinuria > 200mg/mmol - hypoalbuminemia
Epidemiology of nephrotic syndrome
Uncommon - 2 in 100,000 children per year
- higher incidence in UK Asian populations
- twice as common in boys
- most common in early childhood - median age of 4 years
Pathophysiology of nephrotic syndrome
Leaking protein from damaged glomerulus - podocytes become flattened Most commonly caused by minimal change disease in children - congenital nephrotic syndromes - focal segmental glomerulosclerosis - mesangiocapillary glomerulonephritis
Clinical features of nephrotic syndrome
Oedema Proteinuria Hypoalbuminemia Atypical features - discussion with nephrologist - < 1 of > 12 years old - hypertension - impaired renal function - frank haematuria - steroid resistant nephrotic syndrome
Ddx for nephrotic syndrome
Heart failure - heart murmur, SOB, cyanosis or hepatomegaly
Allergic reaction - facial oedema
Malnutrition
Ix for nephrotic syndrome
Confirm diagnosis and rule out atypical features
- urine dip
- urinary protein:creatinine ratio
- U+Es
- FBC
- serum albumin
- varicella zoster serology
Management of nephrotic syndrome
High dose steroids
- usually react well but may relapse
- may require low-dose maintenance steroids
Low salt diet
- to prevent worsening oedema
Prophylactic antibiotics
= leak immunoglobulins through kidneys so higher risk of infection
Complications of nephrotic syndrome
Fluid management
- can be intravascularly depleted even though peripherally oedematous
Infection
Varicella Zoster
- may require VZV immunoglobulin or IV acyclovir
Thrombosis
- prothrombotic state
Pathophysiology of UTIs
Most commonly
- E.Coli
- Klebsiella species
- Staphylococcus saprophyticus
Risk factors for UTIs
Age below one year Female - more common in boys under 3 months Caucasian race Previous UTI Voiding dysfunction Vesicoureteral reflex Sexual abuse Spinal abnormalities Constipation Immunosuppression
Clinical features of UTI
Preverbal infants - vomiting - fever - lethargy - poor feeding - failure to thrive Children who can verbalise - increased frequency - painful urination Examination - increased temp, HR, RR and cap refill time
DDx of UTI
Vulvovaginitis or vaginal foreign body - vaginal discharge with normal urine dip Kawasaki disease - rash, mucositis, swelling of extremities Voiding dysfunction - urine withholding behaviours Sepsis with no UTI source Threadworms - perianal itching Meningitis - photophobia, neck stiffness and rash
Ix for UTI
Microscopy and culture - clean catch urine sample - urine collection pad Urine dipstick - leukocyte esterase and nitrites Consider USS for recurrent UTIs
Atypical features of UTI
Poor urine flow Abdo or bladder mass Raised creatinine Sepsis Failure to respond to treatment in 24 hours Non-E.coli organism
Definition of recurrent UTIs
2 or more episodes of pyelonephritis
One episode of upper UTI and one episode of lower UTI
3x episodes of lower UTI
Management of UTIs
All infants and children 3months + with cystitis/lower UTI - oral abx for 3 days - cefalexin All those with upper UTI - referral to paediatric specialist - oral cefalexin or IV cefuroxime Children over 12 - nitrofurantoin
Complications of UTI
Renal scarring/damage
Hypertension
Renal insufficiency and failure
Risk factors for recurrent UTIs
Younger children - aged less than 6 months
Female
VUR grade 3-5
Voiding abnormalities
Define renal agenesis
Total absence of one or both kidneys
Define multicystic dysplastic kidney
Renal cortex replaced with multiple cysts leaving no functioning cortex
Define horseshoe kidney
Fusion of inferior poles of the 2 kidneys across the midline
- both function independently
Define dulplex kidney
A single kidney has 2 separate pelvicalyceal systems
Define posterior urethral valves
Urethral obstruction from a valve-like fold of tissue
Define autosomal dominant polycystic kidney disease
Multiple progressive cyst formation within the kidneys
Define pelviuretieric junction obstruction
Inadequate canalisation of the pelviureteric junction
- leads to obstruction
NICE guidelines for USS imaging in children < 6 months
USS during acute infection - only if atypical UTI - septic, abdominal mass, raised creatinine, failure to respond to abx, non-E.coli USS within 6 weeks - responds well to treatment in 48 hrs DMSA 4-6 months following - atypical UTI - recurrent UTI MCUG - atypical - recurrent
Define reflux nephropathy
Renal damage due to retrograde flow of urine from the bladder to upper renal tract
- incompetence at vesicoureteric junction
- secondary to obstrcution
- neurogenic bladder
Risk factors for reflux nephropathy
Fhx
Recurrent UTIs
Anatomical renal tract abnormality
Clinical features for reflux nephropathy
Asymptomatic or recurrent UTIs
Mx of reflux nephropathy
Mild
- observation and advice on identifying features of infection
Moderate
- antibiotic prophylaxis to prevent further damage to the kidneys due to infection
Severe
- surgical repair
Features of nephritic syndrome
Proteinuria
Haematuria
Renal failure
Pathophysiology of nephritic syndrome
Inflammation due to glomerulonephritis
Leads to leaky glomerulus
- proteinuria
- haematuria + red cell casts
Increased cellularity reducing glomerular blood flow and filtration
- reduced renal function - rise in creatinine and urea
- salt and water retention -> systemic hypertension, oedema and oliguria
Causes of nephritic syndrome
Post-streptococcal glomerulonephritis
IgA nephropathy
Mx of nephritic syndrome
Manage primary aetiology - PSGN - supportive - IgA nephropathy - ACEi Monitor U+Es eGFR - consider dialysis in acute renal failure Antihypertensives Restrict fluid and salt intake
Define enuresis
Involuntary loss of urine beyond the developmental age of 5
- typically nocturnal
- primary or secondary
Causes of enuresis
Primary - delayed development of the bladder sphincter - neurogenic bladder - dysfunctional voiding - reflux nephropathy Secondary - DM or DI - emotional stress - UTI - CKD - constipation
Mx of enuresis
Positive reinforcement techniques
Enuresis alarms
Evening fluid restriction
Psychological support
