Exacerbation of chronic inflammatory diseases by infectious agents: Fact or fiction?

Table 2 Pathogens associated with increased chronic inflammatory diseases in humans

Pathogen	Effect	Mechanisms	Ref
H. pylori	Affected subjects showed increased insulin resistance	Increased concentrations of plasma glucose and lipids	[64-67]
C. pneumoniae	Increased metabolic syndrome, insulin resistance and cardiovascular disease	Increased production of proinflammatory and circulating cytokines	[68-72]
P. gingivalis	Adults with dental infections demonstrated higher chance of insulin resistance and diabetes	Increased oxidative stress, advanced glycation end-products and altered immune function	[86-90]
HCV	Infected patients showed increased chance to develop insulin resistance and diabetes	Increased production of TNF and IL-6	[92-95]
HIV	HIV patients showed higher insulin resistance (35%) compared to normal subjects (5%)	Impaired glucose tolerance and significant hyperinsulinaemia	[96,97]

H. pylori: Helicobacter pylori; C. pneumoniae: Chlamydia pneumoniae; P. gingivalis: Porphyromonas gingivalis; HCV: Hepatitis C virus; HIV: human immunodeficiency virus; Ref: Reference.