Syphilis-associated membranous nephropathy successfully treated with amoxicillin

Area of Science:

• Nephrology
• Infectious Diseases
• Immunology

Background:

• Membranous nephropathy (MN) is a leading cause of nephrotic syndrome in adults.
• Syphilis, a sexually transmitted infection, is increasingly prevalent globally and in Japan.
• The association between syphilis and nephrotic syndrome is uncommon but recognized.

Observation:

• A 33-year-old Japanese male presented with weight gain and pitting edema.
• Laboratory tests revealed nephrotic-range proteinuria.
• Renal biopsy demonstrated subepithelial deposits consistent with membranous nephropathy.

Findings:

• Active syphilis infection was identified as the underlying cause of the nephrotic syndrome.
• Treatment with amoxicillin for 8 weeks led to a significant reduction in proteinuria within three weeks.
• This highlights a treatable cause of acute-onset membranous nephropathy.

Implications:

• Syphilis should be considered in the differential diagnosis of acute-onset nephrotic syndrome, particularly in younger adults.
• Increased syphilis incidence may lead to a rise in syphilis-associated nephrotic syndrome.
• Early diagnosis and treatment of syphilis are crucial for renal recovery in affected patients.