Therapy with a bactericidal antimicrobial agent or combination of agents is usually effective [
1‐
3], although in some cases antibiotic therapy fails, resulting in end-stage renal failure requiring dialysis therapy. Here, we present a patient complicated with VSD who developed rapidly progressive glomerulonephritis accompanying right sided-subacute bacterial endocarditis caused by Propionibacterium acnes. Although Propionibacteium acnes is considered to be contaminant, it has been found to be a pathogen of infective endocarditis in spite of its weak virulence [
4]. Furthermore, case-reports of shunt nephritis associated with Propionibacterium acnes were also reported [
5‐
7]. Membranoproliferative glomerulonephritis is the lesion most frequently seen in shunt nephritis, but in some patients in whom untreated and inadequately treated bacteremia persists, mild renal involvement may progress to the development of severe impairment such as crescents and sclerotic glomeruli, possibly through the prolonged immune-mediated pathogenesis [
8]. In the present case, the prolonged exposure to the weak pathogen resulted in the development of crescentic glomerulonephritis in association with circulating immune complexes and cryoglobulinemia. Moreover, in the present case, the antibiotic therapy alone was only able to suppress circulating bacteremia, but failed to decrease the size of vegetation and the nest of bacteria. However, the clinical improvement of our case was thought to be a delayed response to continued antibiotic therapy and the addition of anticoaglants [
3,
9,
10]. Some case reports also showed that immunosuppressive therapies such as plasmapheresis, cyclophosphamide, and azathioprine with antibiotics could recover renal dysfunction of infective endocarditis-induced crescentic glomerulonephritis [
3,
11]. Recently, a short-tem and low dose of anti-inflammatory corticosteroid has also shown to be potentially effective in reducing the risk of death in patients with sepsis [
12,
13]. In conclusion, we suggest that patients with rapidly progressive glomerulonephritis associated with infective endocarditis might be treated with a short-term and low dose of corticosteroid successfully, in the case presenting the clinical and biological evidence of immune-mediated pathogenesis with the prolonged duration of the illness.