Primary and Secondary Glomerulonephritis: Causes and Symptoms
Primary Glomerulonephritis
Primary glomerulonephritis involves structural and functional alterations of the glomeruli and is a leading cause of terminal renal failure. These conditions are classified into:
- Acute
- Chronic
Most cases are caused by immunologic processes:
- Autoantibody contribution: Autoantibodies against the basement membrane attach to it, producing membrane inflammation.
- Immune complex entrapment: Circulating immune complexes deposit in the glomerular membranes, triggering an inflammatory response. This is often caused by antigens such as bacteria or viruses, most characteristically the beta-hemolytic Streptococcus.
- In situ formation: A mechanism where immune complexes are formed directly within the glomerulus.
Glomerulonephritis often presents with nephritic syndrome or nephrotic syndrome.
Glomerulonephritis Presenting with Nephritic Syndrome
We will examine the following two types:
Acute Glomerulonephritis (AGN)
AGN is an acute onset of renal disease, often preceded by a streptococcal infection. It is characterized by proteinuria, hematuria, oliguria, decreased glomerular filtration, edema, and hypertension, though it often shows a spontaneous tendency toward recovery.
It produces acute inflammation of the glomeruli and occurs mainly in children aged 3 to 7 and the elderly. The most common primary focus is pharyngo-tonsillar. It typically begins with facial edema that descends to the lower extremities throughout the day.
Rapidly Progressive Glomerulonephritis (RPGN)
RPGN development is rapid and sometimes irreversible. It is produced by glomerular basement membrane damage or various systemic diseases, such as Systemic Lupus Erythematosus (SLE).
Secondary Glomerulonephritis
- Systemic Lupus Erythematosus (SLE): A multisystem, inflammatory, autoimmune disease characterized by the formation of antibodies against multiple nuclear and cytoplasmic antigens. It primarily affects women between 30 and 40 years of age.
- Schönlein-Henoch Purpura: A condition involving systemic skin lesions on the lower limbs, arthralgia, gastrointestinal manifestations, and renal involvement.
- Goodpasture Syndrome: An autoimmune disease that causes pulmonary hemorrhage and anti-glomerular basement membrane glomerulonephritis.
- Necrotizing Vasculitis: A group of disorders characterized by inflammation and necrosis of blood vessels.