Board Review Bonus 6: Hereditary Nephritis

In this "Board Review Bonus" (BRB) episode, hosts Dr. Kenar Jhaveri and Dr. Koyal Jain provide a comprehensive clinical overview of hereditary nephritis—also known as Alport syndrome—a complex genetic condition with critical renal and extrarenal implications. From a sneaky real-world case of an 18-year-old female presenting with isolated microscopic hematuria to classic textbook syndromic features , our hosts break down the essential knowledge required for both board preparation and clinical practice.

The discussion moves beyond the classic X-linked male phenotype to explore autosomal varieties and why thin basement membrane disease (TBMD) is increasingly viewed as part of the Alport spectrum rather than a purely benign entity. Dr. Jain and Dr. Jhaveri emphasize critical management strategies, highlighting why an accurate diagnosis is vital to protect patients from receiving unnecessary and ineffective immunosuppressive therapies.

Key Topics Covered:

• The Hematuria Differential: Evaluating a young patient with a family history of hematuria, prioritizing Alport syndrome, thin basement membrane disease, and IgA nephropathy.
• Genetics and Inheritance Patterns: A detailed look at mutations in the alpha 3, 4, and 5 chains of type IV collagen, spanning X-linked, autosomal recessive, and autosomal dominant variants.
• Clinical and Extrarenal Manifestations: Identifying the classic trio of kidney involvement, high-pitched sensorineural hearing loss, and ocular abnormalities like anterior lenticonus.
• Biopsy and Pathology Pearls: Differentiating between simple glomerular basement membrane (GBM) thinning and advanced longitudinal splitting ("basket-weave" lamination) on electron microscopy, alongside the utility of pediatric skin biopsies.
• Clinical Management & Pitfalls: Navigating first-line RAAS inhibition and SGLT2 inhibitors while strictly avoiding immunosuppressive regimens for secondary FSGS lesions.
• Transplantation Outcomes: Understanding why Alport syndrome does not recur post-transplant, balanced against the 3% to 4% risk of developing de novo anti-GBM disease in the allograft.

Recommended Literature:

• Consensus statement on guidelines for the care of children and adolescents with Alport syndrome.
• Early angiotensin-converting enzyme inhibition in Alport syndrome delays renal failure and improves life expectancy.
• Alport Syndrome: Classification and Management