Alport syndrome is a hereditary disease characterised by progressive sensorineural hearing loss, renal disease and, at times, ocular lesions.
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Clinical presentation
haematuria
sensorineural hearing loss: typically high frequency 2
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ocular abnormalities
anterior lenticonus which may result in cataracts
perimacular pigmentary changes
flecks around the fovea 2
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multiple leiomyomas 1,2
tracheobronchial tree
female genitalia
Pathology
Alport syndrome results from mutations in the type IV collagen genes COL4A3, COL4A4, and COL4A5 8. Type IV collagen is found in the basement membrane of the glomerulus, the cochlea, and the eye.
Genetics
Mutations may be inherited in X-linked dominant (most common), autosomal recessive, or autosomal dominant patterns 7,8. In its most common form, males are more severely affected, although females also demonstrate abnormalities 2.
Associations
Radiographic features
Ultrasound
In the early stage the kidneys are normal in size and echotexture, but in advanced disease they may be atrophic and echogenic. In a patient presenting with new haematuria with an established familial diagnosis of Alport syndrome, the absence of mass or structural abnormality on urinary tract ultrasound is likely to represent Alport syndrome 9.
CT
Kidneys may be shrunken with delayed or non-excretion of contrast in advanced stages.
Multiple leiomyomas can be seen in the oesophagus 5, tracheobronchial tree, or uterus.
MRI
MRI brain may show patchy/nodular lesions in gangliothalamic complexes, with reduced white matter myelination 4.
History and etymology
Named for Arthur Cecil Alport (1880-1959), an English physician.