Polycystic kidney disease, fungi, and bacterial endotoxin: shifting paradigms involving infection and diet

Abstract

The effort to understand the significance of ever-more numerous observations of fungal and bacterial components in tissues and fluids from patients with polycystic kidney disease (PKD) is the focus of this review. Could this second most common genetic disease in man be promoted or even caused by microbes or their components/toxins found in PKD patients? Findings include fungal glucans, fungal antigens, immunoglobulin E reactive with fungal antigens, fungal DNA, bacterial endotoxin from at least three genera, and a newly discovered class of bacteria, Nanobacterium. A new species of fungus, Penicillium pimiteouiense, has been isolated from PKD kidney cells in vitro. What are the sources of these microbes or microbial parts and by what mechanism(s) do they alter those few cells that become the progenitors of all phenotypically cystic cells? Hypotheses concerning the interactions of microbial components with PKD biology are presented along with strategies to confirm and exploit therapeutically these ideas. The study of microbes and their parts in this prominent chronic, genetic disease may provide insights into other polymicrobic, multifactorial diseases.