Renal/ GU Flashcards
What is the aetiology of nephritic syndrome?
- Most common cause is IgA nephropathy
- Bacterial infection (e.g. MRSA)
- Hepatitis B and C
- Schistomiasis
- Malaria
- Post-streptococcal infection
- Infective endocarditis
- SLE
- Systemic sclerosis
- ANCA associated vasculitis
- Goodpastures disease
What is the presentation of nephritic syndrome?
- Haematuria
- Proteinuria
- Hypertension and oedema
- Oliguria
- Uraemia with symptoms (anorexia, pruritus, lethargy and nausea)
- Deteriorating kidney function
- Moderate-severe decrease in GFR
How is nephritic syndrome diagnosed?
- History to determine cause
- Measure eGFR, proteinuria, serum U&E and albumin
- Swab from throat of infected skin
- Urine dipstick for proteinuria and haematuria
- Renal biopsy is necessary
How is nephritic syndrome managed?
Treat underlying cause
- Post-strep = antibiotics
- SLE = steroids, immunosuppression, cyclophosphamide, rituximab
- ANCA-associated vasculitis = immunosuppression, steroids, cyclophosphamide, rituximab, plasma exchange
- Goodpastures = remove antibody via plasma exchange, immunosuppression, steroids/ cyclophosphamide
- IgA nephropathy = BP control with ACEi
- Hypertension = salt restriction and loop diuretics
What is the aetiology of nephrotic syndrome? (Primary and secondary causes)
PRIMARY CAUSES:
- Minimal change disease – most common cause in children
- Membranous neuropathy (can be idiopathic or secondary e.g. drugs, autoimmune, infection, neoplasia)
- Focal segmental glomerulosclerosis
SECONDARY CAUSES:
- Diabetes mellitus
- Amyloid
- Infections (Hep B, C, HIV)
- SLE, RA
- Drugs
- Malignancy
What is the pathophysiology of nephrotic syndrome?
- Basement membrane of the glomerulus is damaged
- Increased permeability to serum protein causing proteinuria
- Leads to low serum protein
What is the presentation of nephrotic syndrome?
- Triad of proteinuria, hypoalbuminemia and oedema
- Normal/mild increase BP
- Normal/mild decrease GFR
- Frothy urine
What are the differential diagnosis of nephrotic syndrome?
- Congestive heart failure
- Cirrhosis
How is nephrotic syndrome diagnosed?
- Establish cause with renal biopsy
- Urine dipstick – high protein
- CXR or CUUS – pleural effusion/ ascites
- Low serum albumin
- Serum creatinine, eGFR, lipids and glucose
How is nephrotic syndrome managed?
- Treat underlying cause
- TO REDUCE OEDEMA: loop diuretics, thiazide diuretics, fluid and salt restriction
- TO REDUCE PROTEINURIA: prophylactic anticoagulation with warfarin, statins for cholesterol, treat infections and vaccinate
What is the aetiology of polycystic disease?
- Mutations in PKD1 genes on chromosome 16
- Mutations in PKD2 genes on chromosome 4
What is the pathophysiology of polycystic disease?
- PKD1 encodes polycystin 1 which is involved in cell-cell and cell-matrix interactions (regulated tubular and vascular development in kidneys)
- PKD2 encodes polycystin 2 (a calcium ion channel)
- Polycystin complex occurs in cilia responsible for sensing tubule flow
- Disruption in this causes reduced cytoplasmic Ca2+, resulting in cyst formation
- Rate of renal function decline is dependent on size and growth of cysts
What are the risk factors of polycystic disease?
- Family history – commonest inherited kidney disease
- FHx of ESRF
- FHx of hypertension
What is the presentation of polycystic disease?
- Can be clinically silent for many years, so family screening is essential
- Loin pain, haematuria from haemorrhaging into cyst
- Excessive water and salt loss
- Nocturia
- Bilateral kidney enlargement
- Renal colic due to clots
- Hypertension
- Renal stones
- Progressive renal failure
- Polycystic liver disease
- Pancreatitis
- Ovarian cysts
What are the differential diagnoses of polycystic disease?
- Acquired and simple cysts of the kidneys
- Autosomal recessive PKD
- Medullary sponge kidney
- Tuberous sclerosis
