Inherited Renal Disorders Flashcards
(56 cards)
What are the two forms of polycystic disease?
Autosomal recessive or dominant (common)
What is the aetiology of autosomal dominant polycystic kidney disease?
Most frequent life threatening hereditary disease
Important cause of ESRD = 8-10% of ESRD in Europe and Australia
What are the mutations implicated in autosomal dominant PKD?
PKD1 (85%) and PKD2 (15%)
What are some features of the PKD1 mutation in autosomal dominant PKD?
Located on chromosome 16, patients develop end stage kidney failure at an earlier stage than PKD2 patients
Where is the PKD2 mutation of autosomal dominant PKD located?
Located on chromosome 14
What is the histological appearance of autosomal dominant PKD?
Massive cyst enlargement = large kidneys
Epithelial lined cysts arise from a small population of renal tubules
Benign adenomas occur in 25%
What are the renal features of autosomal dominant PKD?
Reduced urine concentrating ability
Chronic pain and renal failure
Haematuria = cyst rupture, cystitis, stones
Cyst infection
Hypertension = common, mean age of onset is 31
What is the most common extra-renal manifestation of autosomal dominant PKD?
Hepatic cysts = present 10 years after renal cysts, liver function generally preserved
What may hepatic cysts associated with autosomal dominant PKD cause?
SOB, pain and ankle oedema
What are some extra-renal manifestations of autosomal dominant PKD?
Hepatic cysts, intra-cranial aneurysms, cardiac disease, diverticular disease, hernias
What are some features of the intra-cranial aneurysms associated with autosomal dominant PKD?
4-8% of patients, seen in clusters in families, mainly in the anterior circulation territory, screening indicated if positive family history
What cardiac diseases are associated with autosomal dominant PKD?
Mitral or aortic valve prolapse
Valvular disease = collagenous/myxomatous degeneration
What are the features of diverticular disease associated with autosomal dominant PKD?
Increased prevalence and incidence of complications, usually patients on dialysis, may have diverticulitis or colonic perforation
How common are hernias in patients with autosomal dominant PKD?
45% of patients have inguinal hernias
Also increased incidence of abdominal hernias
What is the radiological diagnosis of autosomal dominant PKD?
US sounds shows prevalence of multiple bilateral cysts and renal enlargement, CT/MRI used if US unclear
How is genetic diagnosis used in autosomal dominant PKD?
Linkage analysis and mutation analysis
How does autosomal dominant PKD present in children?
Early onset = can be in utero or first year of life
Siblings are at increased risk of early disease
How are children affected by autosomal dominant PKD?
Renal involvement similar to adults but cerebral aneurysms are rare
Single cyst in high risk patient is enough for diagnosis
How can autosomal dominant PKD in children be differentiated from autosomal recessive PCK?
Using US = presence of congenital hepatic fibrosis is suggestive of recessive disease
What is the chance of the children of someone with autosomal dominant PKD developing the disease?
50%
When should genetic counselling be offered to patient with autosomal dominant PKD?
Both pre and post-testing is required in any patient at risk and who are planning to undergo diagnostic testing
What is the management of autosomal dominant PKD?
Rigorous hypertension control, hydration, proteinuria reduction, cyst haemorrhage or infection control, dialysis or transplant if renal failure
What new drug can be used to treat autosomal dominant PKD?
Tolvaptan = reduces cyst volume and progression
Who is primarily affected by autosomal recessive PKD?
Young children = commonly associated with hepatic lesions
