Rare Renal Disorders: It Isn’t Always Acute Kidney Injury (AKI)
Nephrology care team members who perform dialysis therapies are often only peripherally exposed to patients with rare renal conditions. At times, a patient receiving hospital care can have unforeseen complications if underlying processes of a rare disease that are not considered during the course of hospitalization go untreated. Alport Syndrome is one such rare renal disorder estimated to affect 1 in 5,000-10,000 people in the United States.
Alport Syndrome is a genetically associated condition and can be either autosomal recessive or, less frequently, autosomal dominant in nature. It is an X-chromosome-related deficiency of genetic code and occurs with near equal prevalence in males and females.
The progressive pathophysiology is related to absent genetic coding that normally provides instruction for the production of type IV collagen, a key component in glomerular health and function. The glomeruli are groups of blood vessels tasked with filtration of water and blood creating urine. Without the type IV collagen, the lack of protein-provided strength causes the basement layer of the kidney to separate microscopically. Hematuria occurs and ultimately the membrane and glomeruli are scarred and unable to produce urine.
Diagnosis is typically made in late adolescence with a sequelae of progressive symptoms that include visual deterioration, hearing loss, proteinuria and hematuria. Renal dysfunction related to the disruption of the glomerular basement layer can lead to complete renal failure. Definitive diagnosis is made via renal biopsy. Alport Syndrome is represented microscopically with a hallmark appearance known in pathology as a lamellated basket-weave.
Patients receive education related to eye protection early in the course of the disease and frequent ophthalmology exams to monitor for anterior lenticonus—a localized, cone-shaped deformity of the anterior lens surface which can be surgically corrected in most cases. Patients who work in a noisy environment are instructed to use ear protection. Hearing aids are often necessary in late adolescence or early adulthood, with a high number of patients experiencing complete hearing loss around the age of 40. Other concerns that are addressed relate to chronic renal failure including aggressive blood pressure control, fluid restrictions and dietary changes.
Chronic kidney failure related to Alport Syndrome will ultimately require dialysis or renal transplant.
If you would like to learn more about symptoms of Alport Syndrome and other genetically associated diseases visit The Human Phenotype Ontology page, an international consortium dedicated to biomedical data collection, publication and updates.