In Pursuit of a Stealth Pathogen: Laboratory Diagnosis of Bartonellosis

Members of the genus Bartonella cause illnesses in humans and animals. Bartonella spp. are gram-negative, fastidious, facultative, intracellular pathogens transmitted by the bites of certain arthropods or by bites and scratches from infected animals. While some of the illnesses are acute and self-limiting, others are chronic, debilitating, and difficult to diagnose. Bartonella spp. are able to invade host cells and modulate the host immune response, contributing to their success as stealth pathogens. This article provides an overview of diseases caused by members of the genus Bartonella and the mechanisms of pathogenesis. The laboratory diagnosis of bartonellosis relies on three primary methods. This article examines the evolution of culture techniques, serology, and nucleic acid amplification tests used to detect Bartonella spp. in clinical specimens and suggests areas for future research to improve laboratory diagnostics. In this way, a better understanding of the epidemiology of bartonellosis can be achieved.