Microbiology

Abstract

Microbiological investigations of specimens from anatomical structures adjacent to the oral cavity are always difficult to interpret concerning the relevance of the bacteria isolated. In case of an osteomyelitis of the jaws the detection of Staphylococcus aureus is often relevant and coagulase-negative staphylococci can be responsible for implant associated infections. Staphylococci are normally not found in the oral cavity; the susceptibility pattern of staphylococci is essential for adequate treatment; however, tissue samples as well as swabs from the infected jaw reveal mostly aerobic and anaerobic bacteria, e.g., viridans streptococci, Eikenella corrodens, peptostreptococci, Fusobacterium spp., and Actinomyces spp. All these bacteria can be innocent bystanders or infectious agents, but are mostly susceptible to clindamycin or amoxicillin−clavulanate; therefore, microbiological investigations are only helpful in case of osteomyelitis of the jaws, if specimens can be taken without contamination from the oral cavity. Furthermore, the laboratory must be informed if specific infections are suspected, e.g., actinomycosis, because selective agar plates must be inoculated and a prolonged incubation time up to 10 days is necessary. In case of a diagnosed primary chronic osteomyelitis of the jaws, interpretation of any isolated bacterium must be done with caution. Nevertheless, if the samples were taken without contamination from the oral cavity, the possible relevance of an unexpected bacterium should not be ignored. In conclusion, routine microbiological investigations of osteomyelitis affecting the jawbone usually do not have a major clinical impact, unless a special clinical situation is present. In such cases, preanalytic precautions, i.e., sampling technique and transport media for anaerobes, must be respected; otherwise, microbiological results are not promising.