Prevotella intermedia and
P. nigrescens are associated with inflammatory
periodontal diseases, such as pregnancy gingivitis, acute
necrotizing ulcerative gingivitis and adult
periodontitis. Together with
Porphyromonas gingivalis they are known as black-pigmenting anaerobes. All three require
haemin to provide
iron for their growth. These species were shown to bind
lactoferrin that is released together with the contents of
neutrophils during inflammation and bleeding in periodontitis patients. Lactoferrin inhibits the growth of
P. gingivalis but not
Prevotella. Inorganic iron and iron-binding proteins such as
transferrin and lactoferrin do not support the growth of
P. intermedia, however hemin–iron-containing compounds which include hemin, human
hemoglobin, bovine hemoglobin, and bovine
catalase stimulate the growth of
P. intermedia. Hemoglobin-binding protein on the cell surface of
P. intermedia has been described. Some studies have linked abnormal levels of
Prevotella copri and
rheumatoid arthritis. An overgrowth of
Prevotella and a reduction of
Lactobacillus correlated with the onset of
osteomyelitis in mice. The reduction of
Prevotella in model mice led to an increase of
Lactobacillus showing a protection effect against osteomyelitis. Thus, changes in the
Prevotella microbiota may be related to the development of
osteomyelitis. Approximately 70% and 30% of
Prevotella are resistant to
penicillin and
clindamycin, respectively, while resistance to
amoxicillin/clavulanate and
metronidazole is reported in less than 10% of the clinical strains responsible for bloodstream infections in humans. == Species ==