• Clinical science

Poststreptococcal glomerulonephritis (Postinfectious glomerulonephritis)

Abstract

Poststreptococcal (or postinfectious) glomerulonephritis (PSGN) refers to acute glomerular inflammation that results from a preceding infection with nephritogenic strains of streptococci. Although most commonly seen in children following group A streptococcal tonsillopharyngitis, skin infections such as impetigo may trigger PSGN as well. Deposition of immune complexes containing the streptococcal antigen within the glomerular basement membrane results in complement activation and subsequent damage to the glomeruli. PSGN typically presents as a nephritic syndrome with hematuria, mild proteinuria, edema, and hypertension. Elevated antistreptolysin O titers (ASO), low complement levels, and elevated creatinine support the diagnosis. In children, close monitoring and supportive therapy facilitate the recovery process. While most children recover fully, the prognosis in adults is typically less favorable.

Epidemiology

  • Mostly affects children (between the ages of 3–12 years); and patients > 60 years of age
  • The incidence has decreased in developed countries due to the systematic use of antibiotics and improved hygienic standards.

References:[1][2][3]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

References:[1][4]

Pathophysiology

References:[2]

Clinical features

References:[1][4]

Diagnostics

References:[1][2][4]

Differential diagnoses

The differential diagnoses listed here are not exhaustive.

Treatment

In most cases the disease is self-limiting and only supportive treatment focused on the complications of volume overload is necessary.

References:[2][4][3]

Complications

Complications are more common in adults:

References:[1]

We list the most important complications. The selection is not exhaustive.

Prognosis

  • Recovery usually occurs within 6–8 weeks.
    • In children: restitution of kidney function in > 90% of cases
    • In some cases, urinalysis may remain abnormal for extended periods. Follow-ups are therefore important!
  • In adults, about 50% of patients suffer from persistently reduced renal function.

References:[1][3]