Endocarditis in Chickens Caused by Subclinical Infection of Streptococcus gallolyticus subsp. gallolyticus

Abstract

Streptococcus gallolyticus subsp. gallolyticus causes endocarditis in humans and acute septicemia in domestic birds. We describe here the infective endocarditis caused by the bacterium found among clinically healthy broilers at two abattoirs in Japan. The chickens were thought to be healthy because of the lack of clinical symptoms and normal levels of mortality before slaughtering. At the time of inspection, some chickens were condemned because of organ disorders characterized by vegetative valvular endocarditis as well as focal necrosis in heart, liver, and spleen. Streptococcus gallolyticus subsp. gallolyticus was isolated from the organs as a pure culture, indicating that the bacterium probably was the causative agent of the disorders. Amplified fragment length polymorphism analysis of the isolates collected at the abattoirs from chickens grown in nine different farms indicated that the isolates were different variants of the same clonal lineage and may have been derived from the same ancestor. These results suggest that S. gallolyticus subsp. gallolyticus causes infectious endocarditis in chickens and that healthy chickens may possess the bacterium in their normal flora as an opportunistic pathogen.

A Longitudinal Case Series Description of Meningitis Due to Streptococcus gallolyticus subsp. pasteurianus in Infants

“…S. bovis species are a known cause of septicemia and sudden death in fowl, including pigeons, turkeys, chickens, and goslings (1,12). This exposure history could be a potential clue to the etiology of this patient's S. gallolyticus subsp.…”

Development and Application of a Multilocus Sequence Typing Scheme for Streptococcus gallolyticus subsp. gallolyticus

“…The organism can also act as a pathogen. This opportunistic bacterium may cause septicemia and meningitis in animals, as well as in humans (3,4). In 24% of cases of streptococcal endocarditis, S. gallolyticus subsp.…”

“…Nevertheless, S. gallolyticus subsp. gallolyticus has been found in various animals, especially in pigeons, chickens, and cattle, where it can cause various diseases (4,9,10). Particularly in dairy cows, it is often the causative agent of mastitis (11).…”

“…However, the transmission pathways, as well as the pathogenic mechanisms, remain unexplained. Because of its presence in, e.g., poultry, ruminants, and humans, it is suspected but has not been confirmed to have zoonotic potential (4,(8)(9)(10)15).…”

Antimicrobial Susceptibility of <i>Streptococcus gallolyticus</i> Isolated from Humans and Animals

“…However, a small number of bacterial isolates from healthy mammals showed resistance, which was probably because of differences in the amounts of these antimicrobials administered to the animals (e.g., feed additives, veterinary treatment). Recently, the frequency of infections caused by S. gallolyticus has increased in both humans and domestic animals (14). Therefore, continuous monitoring for antibioticresistant S. gallolyticus is needed to determine appropriate treatments for diseases caused by this bacterium.…”