Biomaterial Database

Increased incidence of urolithiasis and bacteremia during Proteus mirabilis and Providencia stuartii coinfection due to synergistic induction of urease activity. 2014

Chelsie E Armbruster, and Sara N Smith, and Alejandra Yep, and Harry L T Mobley

Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan.

BACKGROUND Catheter-associated urinary tract infections (CaUTIs) are the most common hospital-acquired infections worldwide and are frequently polymicrobial. The urease-positive species Proteus mirabilis and Providencia stuartii are two of the leading causes of CaUTIs and commonly co-colonize catheters. These species can also cause urolithiasis and bacteremia. However, the impact of coinfection on these complications has never been addressed experimentally. METHODS A mouse model of ascending UTI was utilized to determine the impact of coinfection on colonization, urolithiasis, and bacteremia. Mice were infected with P. mirabilis or a urease mutant, P. stuartii, or a combination of these organisms. In vitro experiments were conducted to assess growth dynamics and impact of co-culture on urease activity. RESULTS Coinfection resulted in a bacterial load similar to monospecies infection but with increased incidence of urolithiasis and bacteremia. These complications were urease-dependent as they were not observed during coinfection with a P. mirabilis urease mutant. Furthermore, total urease activity was increased during co-culture. CONCLUSIONS We conclude that P. mirabilis and P. stuartii coinfection promotes urolithiasis and bacteremia in a urease-dependent manner, at least in part through synergistic induction of urease activity. These data provide a possible explanation for the high incidence of bacteremia resulting from polymicrobial CaUTI.

UI	MeSH Term	Description	Entries
D008808	Mice, Inbred CBA	An inbred strain of mouse that is widely used in BIOMEDICAL RESEARCH.	Mice, CBA,Mouse, CBA,Mouse, Inbred CBA,CBA Mice,CBA Mice, Inbred,CBA Mouse,CBA Mouse, Inbred,Inbred CBA Mice,Inbred CBA Mouse
D011512	Proteus Infections	Infections with bacteria of the genus PROTEUS.	Infections, Proteus,Infection, Proteus,Proteus Infection
D011513	Proteus mirabilis	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that is frequently isolated from clinical specimens. Its most common site of infection is the urinary tract.
D011532	Providencia	Gram-negative rods isolated from human urine and feces.
D004756	Enterobacteriaceae Infections	Infections with bacteria of the family ENTEROBACTERIACEAE.	Enterobacterial Infections,Cronobacter Infections,Infections, Enterobacteriaceae,Infections, Enterobacterial,Cronobacter Infection,Enterobacteriaceae Infection,Enterobacterial Infection,Infection, Cronobacter,Infection, Enterobacteriaceae,Infection, Enterobacterial,Infections, Cronobacter
D004790	Enzyme Induction	An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.	Induction, Enzyme
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014510	Urease	An enzyme that catalyzes the conversion of urea and water to carbon dioxide and ammonia. EC 3.5.1.5.	Phytourease,Urea Amidohydrolase,Amidohydrolase, Urea
D015964	Gene Expression Regulation, Bacterial	Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.	Bacterial Gene Expression Regulation,Regulation of Gene Expression, Bacterial,Regulation, Gene Expression, Bacterial
D016470	Bacteremia	The presence of viable bacteria circulating in the blood. Fever, chills, tachycardia, and tachypnea are common acute manifestations of bacteremia. The majority of cases are seen in already hospitalized patients, most of whom have underlying diseases or procedures which render their bloodstreams susceptible to invasion.	Bacteremias