A 28-Year-Old Man With Hemoptysis and Shortness of Breath: Osmosis USMLE Study Question of the Week

February 24, 2017

Answer: D. Production of antibodies against basal membrane

Goodpasture syndrome, also known as anti-glomerular basement antibody disease, is a type II hypersensitivity reaction. This syndrome arises from immunoglobulin G (IgG) antibodies that bind to the glomerular basement membrane cell surface (in the kidney or lung), leading to the activation of complement and proteases. This activation produces damage of the membrane and protein liberation to the urinary space facilitating the formation of crescents. In the lung, antibody mediated damage produces necrotizing hemorrhagic interstitial pneumonitis.

Unlike most autoimmune diseases, Goodpasture syndrome classically occurs in adult males. Clinical features, include hemoptysis, chest pain, cough, shortness of breath, blood in urine (hematuria), protein in the urine (proteinuria), unexplained swelling of limbs or face, and high blood pressure. In most cases, lung symptoms usually antedate kidney symptoms. Although the causes of Goodpasture syndrome are not fully understood, exposure to organic solvents, tobacco smoke, or certain genetic mutations (ie, HLA-DR2) are related to the development of this syndrome.

The diagnosis is usually made with a renal biopsy, which shows a linear immunofluorescence staining of IgG and C3 deposits in the glomerular basement membrane. Another classic feature is the presence of autoantibodies against the α3 chain of type IV collagen (a type of collagen found primarily in glomerular and alveolar basement membranes).

Major Takeaway: Goodpasture syndrome is a type II hypersensitivity reaction characterized by the presence of anti-glomerular basement IgG antibodies. Classically, patients with Goodpasture syndrome are adult males with hemoptysis and clinical features of renal failure.

For more on Goodpasture syndrome, read here.

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