Alport

for speech-language pathologist and audiologist

1. ALPORT SYNDROME

2. INTRODUCTION ALPORT (1927) described the features of “HEREDITARY ALPORT SYNDROME” Alport syndrome is otherwise called as “single gene syndrome” One of the important characteristic features are “HEREDITARY NEPHRITIS AND DEAFNESS”

3. MODE OF INHERITANCE Alport syndrome is inherited in an “X-linked” pattern due to mutations in the COL4A5 gene. In males, who have only one X chromosome one altered copy of the COL4A5 gene is sufficient to cause severe alport syndrome. In female who have two X chromosomes, a mutation in one copy of the col4A5 gene usually results in blood in the urine. Autosomal domination inheritance.

4. INCIDENCE The disorder is uncommon, and most often affects males. Women can transmit the gene for the disorder to their children, even if they have no symptoms. 74% of males are usually diagnosed as having the disease before age 6.

5. PREVALENCE Alport syndrome is approximately reported 1 of 5000 births.

6. CHARACTERISTIC FEATURES Chronic nephritis Renal disease->ultra structural changes of the glomerular capillary basement membrane with absence of the immune phenomenon seen in other glomerular disease.

7. SYMPTOMS Hematuria Nephropathy Hypertension in female patients Slow progressive hearing loss

8. HEARING CHARACTRISTICS In Alport syndrome “BILATERAL PROGRESSIVE SENSORINEURAL HEARING IMPAIRMENT” Genetically based hearing impairment The hearing impairment occurs more frequently in patients and begins with gradual onset at about age 10. Loss of cochlear neurons and haircells Atrophy of striavascularis and spiral ligament and endolympatic hydrops .

9. According to Rintleman(1976) 3 types of audiogram -trough shaped -slop and flat shaped Bilateral symmetrical hearing loss Degree of hearing loss ranges from mild to severe

10. SPEECH CHARACTERISTICS Lack of articulation precision with high frequency consonants such as “fricatives” Difficulty in monitoring vocal frequency and intensity level and in controlling the stress effort of speech production.

11. MANAGEMENT GENETICS AND MEDICAL:- Primary medical concern will be centered around maintenance of renal function. Heamodilusis (or) kidney transplantation may be necessary in severe cases of nephritics . Careful review of family pedigree is essential in differentiating between modes of inheritance

12. HEARING In view of the progressive nature of this disorder, careful and frequent monitoring of audiological status and amplification program is strongly advised.

13. SPEECH Aural rehabilitation, speech therapy and hearing aid fitting

14. PROGNOSIS Poor prognosis for affected male patient Fair to good for affected female patients Careful longterm follow up is necessary

15. BY ANITHA & GAYATHRI

16. Thank you