Rare Diseases - Alport syndrome

The key features of this inherited cause of kidney failure are summarised by Dr Raj Thakkar.

What is it?

  • Alport syndrome is a rare inherited disorder, which can lead to nephritis and deafness.
  • It accounts for around one in 500 cases of end-stage renal failure.

Who is at risk?

  • X-linked Alport syndrome is the most common genetic anomaly. However, a number of different genetic abnormalities have been identified, all of which cause type IV collagen defects.
  • An abnormal glomerular basement membrane secondary to the collagen defect underpins the renal component of the disease.
  • Males are more seriously affected than females in X-linked disease, while males and females are affected equally in autosomal dominant or recessive disease. Carriers may also be symptomatic, albeit mildly. This article relates mainly to X-linked Alport syndrome.

How does it manifest?

  • Alport syndrome is a progressive disease that often presents with haematuria in early childhood.
  • Frank haematuria may be precipitated by respiratory tract infections. The absence of haematuria has a good negative predictive value for Alport syndrome.
  • Proteinuria tends to present later in life and may progress to nephrotic range. Renal hypertension complicates Alport syndrome.
  • About nine in 10 patients progress to end-stage renal failure by their fifties. Risk of progression depends on a number of factors, including the genetic mutation underlying the disease.Renal failure is far more significant in males with X-linked Alport syndrome.
  • Hearing and visual disturbance usually presents in childhood or in early teens. Sensorineural deafness affects most patients. Hearing loss pre-dates renal failure.
  • Ocular manifestations include lenticonus and retinopathy. Other complications include oesophageal and pulmonary leiomyomas, which may cause pain, dysphagia, vomiting, cough, breathlessness and stridor.
  • Some subtypes of Alport syndrome cause bleeding problems secondary to platelet dysfunction and megathrombocytopenia on their blood film. White cell abnormalities may be found.

How is it managed?

  • Patients who progress to end-stage renal failure do well with renal transplantation. In a small minority, the transplanted kidney may develop anti-glomerular basement membrane disease, which destroys the transplant.
  • ACE inhibitors may delay progression to renal failure and help to control hypertension.
  • Surgical, ENT and ophthalmic intervention may be required for complications.
Dr Thakkar is a GP in Wooburn Green, Buckinghamshire

Have you registered with us yet?

Register now to enjoy more articles and free email bulletins

Register

Already registered?

Sign in

Follow Us:

Just published

Death certification during the coronavirus outbreak

Death certification during the coronavirus outbreak

The MDU's Dr Ed Nandasoma answers questions relating to certifying deaths in all...

Coronavirus: Key guidance GPs need to know about COVID-19

Coronavirus: Key guidance GPs need to know about COVID-19

GPonline provides an overview of the key guidance relating to coronavirus, including...

NICE publishes rapid guidance on managing COVID-19 in primary care

NICE publishes rapid guidance on managing COVID-19 in primary care

New guidance on symptom management in patients with suspected and confirmed COVID-19...

GPs fear missing vital COVID-19 advice as data avalanche swamps NHSmail

GPs fear missing vital COVID-19 advice as data avalanche swamps NHSmail

GPs risk missing vital information during the COVID-19 pandemic because a deluge...

GPs can use NHS volunteers service to check on vulnerable patients

GPs can use NHS volunteers service to check on vulnerable patients

GPs can refer vulnerable patients to the NHS volunteer scheme for support with tasks...

Free coronavirus news and resources on GPonline, MIMS and MIMS Learning

Free coronavirus news and resources on GPonline, MIMS and MIMS Learning

As the coronavirus crisis continues, we at Haymarket are constantly seeking new ways...