In the past, the majority of cases of bacterial infection-associated glomerulonephritis occurred in children following streptococcal upper respiratory tract or skin infections. Over the past four decades, there has been a shift in epidemiology, bacteriology, and outcome of this disease. A significant percentage of cases now target adults, particularly the elderly or immunocompromised. Streptococcus-associated glomerulonephritis generally begins after the pharyngeal (more common) or skin infection has either resolved spontaneously or has been effectively treated and therefore the term poststreptococcal glomerulonephritis is appropriate. In contrast, most of the other causes of bacterial infection-associated glomerulonephritis, including that due to staphylococcus infection, occur when the infection is still present and hence the term staphylococcus-associated glomerulonephritis is more appropriate. Streptococcus and staphylococcus are by far the most common bacteria responsible for bacterial infection-associated glomerulonephritis, although a large variety of other bacteria, such as Escherichia, Yersinia, Salmonella, and pseudomonas, can rarely cause the disease. We will limit our considerations to four specific disease entities: (1) acute poststreptococcal glomerulonephritis, (2) staphylococcus-associated glomerulonephritis, (3) infective endocarditis-associated glomerulonephritis, and (4) glomerulonephritis associated with infected atrioventricular shunts (shunt nephritis).
ESSENTIALS OF DIAGNOSIS
Acute nephritic syndrome (hematuria, edema, hypertension, ± oliguria), occasionally nephrotic syndrome, and rarely rapidly progressive azotemia
Recent bacterial infection (serology or culture)
Reduced serum complement (CH50 and C3)
Renal biopsy confirmation required in adults
Exudative glomerulonephritis associated with streptococcus, crescentic glomerulonephritis with infectious endocarditis, and membranoproliferative glomerulonephritis with shunt nephritis
Frequently IgA dominant glomerular staining on immunofluorescence in staphylococcus-associated glomerulonephritis
ACUTE POSTSTREPTOCOCCAL GLOMERULONEPHRITIS
The incidence of acute poststreptococcal glomerulonephritis (APSGN) has decreased dramatically in most industrialized countries. The association with alcoholism in adult patients has been noticed in central Europe. Nevertheless, in other countries, such as Singapore, Trinidad, and Venezuela, a poststreptococcal etiology is the causative factor in more than 70% of children admitted to the hospital with glomerulonephritis. The reason for these geographic variations in epidemiology may relate to the accessibility of early medical care and antibiotic treatment resulting from improvements in living standards. APSGN presents as sporadic cases, clusters of cases, or epidemics that follow streptococcal infections of the throat or the skin. The vast majority of epidemics and sporadic cases were due to group A streptococci, but several outbreaks caused by group C streptococci, group G streptococci, or milk-borne Streptococcus zooepidemicus have been reported.
Streptococci of M types 47, 49, 55, and 57 are frequently the etiologic agents of pyodermitis-associated nephritis while types 1, 2, 4, and 12 correspond to upper respiratory streptococcal infections causing nephritis. There is a wide variability in the incidence of nephritis following a nephritogenic streptococcal infection, but the incidence among siblings is close to 40%, which indicates a familial predisposition to the disease; however, a genetic marker of susceptibility for APSGN has not been found.
APSGN is usually, but not exclusively, a disease ...