Inflammation as a cause for other physiological or even psychiatric problems

[Jhanananda]

Could Depression Be Caused By An Infection?

Sometime around 1907, well before the modern randomized clinical trial was routine, American psychiatrist Henry Cotton began removing decaying teeth from his patients in hopes of curing their mental disorders. If that didn't work, he moved on to more invasive excisions: tonsils, testicles, ovaries and, in some cases, colons.

Cotton was the newly appointed director of the New Jersey State Hospital for the Insane and was acting on a theory proposed by influential Johns Hopkins psychiatrist Adolf Meyer, under whom Cotton had studied, that psychiatric illness is the result of chronic infection. Meyer's idea was based on observations that patients with high fevers sometimes experience delusions and hallucinations.

Cotton ran with the idea, scalpel in hand.

In 1921 he published a well-received book on the theory called The Defective Delinquent and Insane: the Relation of Focal Infections to Their Causation, Treatment and Prevention. A few years later The New York Times wrote, "eminent physicians and surgeons testified that the New Jersey State Hospital for the Insane was the most progressive institution in the world for the care of the insane, and that the newer method of treating the insane by the removal of focal infection placed the institution in a unique position with respect to hospitals for the mentally ill." Eventually Cotton opened a hugely successful private practice, catering to the infected molars of Trenton, N.J., high society.

Following his death in 1933, interest in Cotton's cures waned. His mortality rates hovered at a troubling 45 percent, and in all likelihood his treatments didn't work. But though his rogue surgeries were dreadfully misguided and disfiguring, a growing body of research suggests that there might be something to his belief that infection — and with it inflammation — is involved in some forms of mental illness.

In focal infection theory (FIT), a localized infection, typically obscure, disseminates microorganisms or their toxins elsewhere within the individual's own body and thereby injuries distant sites, where ensuing dysfunction yields clinical signs and symptoms and eventually disease, perhaps systemic and usually chronic, such as arthritis, atherosclerosis, cancer, or mental illness.[1][2][3][4] (Distant injury is focal infection's key principle, whereas in ordinary infectious disease, the infection itself is systemic, as in measles, or the initially infected site is readily identifiable and invasion progresses contiguously, as in gangrene.)[5][6] This ancient concept took modern form around 1900, and was widely accepted in Anglosphere medicine by the 1920s.[4][6][7][8]

In the theory, the focus of infection is often unrecognized, while secondary infections might occur at sites particularly susceptible to such microbial species or toxin.[6] Several locations were commonly claimed as foci—appendix, urinary bladder, gall bladder, kidney, liver, prostate, and nasal sinus—but most commonly oral tissues. Not only chronically infected tonsils and dental decay, but also sites of dental restoration and root canal therapy were indicted as the foci.[4][6] The putative oral sepsis was countered by tonsillectomies and tooth extractions, including of endodontically treated teeth and even of apparently healthy teeth, newly popular approaches—sometimes leaving individuals toothless—to treat or prevent diverse chronic diseases.[4]