A young man with Propionibacterium acnes-induced shunt nephritis

Abstract

SUMMARY This case illustrates in a striking manner the potential renalcomplications associated with chronic, unrecognized VAshunt infection. The diagnosis of shunt nephritis is challen-ging and, as exemplified by this case, may be overlooked forseveral years, resulting in significant morbidity in the form ofongoing renal injury with proteinuria and renal failure. Thefinding of hematuria, proteinuria and even mild renalinsufficiency in a patient with a VA shunt should promptan aggressive microbiologic diagnostic evaluation to excludesubacute infection. Renal biopsy should be considered todocument the pathognomonic membranoproliferative lesionand to assess the relative degrees of acute versus chronicinjury. Further, this case highlights the critical importance ofexcluding secondary forms of disease in any patient with anephritic presentation and biopsy findings demonstratingmembranoproliferative features, as identification and treat-ment of the underlying condition may lead to remission ofproteinuria and normalization of renal excretory function,even in patients with a baseline biopsy finding of significantsclerosis alongside ongoing active inflammation, as was thecase in this patient. Finally, in this exciting era where theelucidation of entire microbial genome sequences has becomepossible, future studies correlating bacterial genomes andproteomes with specific mechanisms of disease may holdpromise for identifying specific antigens involved in thepathogenesis of immune-mediated conditions, such as shuntnephritis.