Asymptomatic glomerulonephritis after nonstreptococcal upper respiratory infections

Area of Science:

• Nephrology
• Virology
• Immunology

Background:

• Upper respiratory infections (URIs) are common, but their association with kidney disease is not fully understood.
• Distinguishing post-infectious glomerulonephritis from other causes is crucial for appropriate management.

Purpose of the Study:

• To investigate the incidence and clinicopathologic features of glomerulonephritis following nonstreptococcal URIs.
• To identify potential viral pathogens associated with this kidney condition.

Main Methods:

• Prospective study of 240 military personnel with nonstreptococcal URIs.
• Urinalysis, renal biopsy, serologic testing for viruses (adenovirus, influenza A/B), and complement level assessment.
• Follow-up with repeat biopsies and creatinine clearance measurements.

Main Results:

• Nine patients developed glomerulonephritis without preceding streptococcal infection.
• Four patients showed reduced complement levels; five had serologic evidence of adenovirus or influenza A/B infection.
• Renal biopsies revealed mesangial proliferation and C3 deposits; some showed improvement on repeat biopsy.
• Five patients experienced persistent reduced creatinine clearance (74-90 mL/min/1.73 m2) for 2-8 months.

Conclusions:

• Nonstreptococcal URIs are frequently associated with glomerulonephritis.
• Virus-associated glomerulonephritis can present with persistent glomerular abnormalities and impaired kidney function.