Since Nobel Laureates J. Robin Warren, AC, and Barry J. Marshall, AC, FRACP, FRS, FAA, DSc, implicated Helicobacter pylori as a causative agent in the pathogenesis of peptic ulcer disease, infection has been proposed as the root cause of multiple disease processes. In recent years, the collection of all the microorganisms living in association with the human body, otherwise known as the microbiome, has gained much attention. Attention to this topic peaked when the White House announced the $121-million National Microbiome Initiative.
The study of the microbiome is now possible largely due to advances in next generation genetic sequencing or NGS, which allows for comprehensive sequencing of all DNA material present in any given sample.
Microbiomes and arthritis
Despite the variability of organisms throughout the human body, some stability at the level of the microbial community suggests the microbiome plays a role in preserving function. The host-microbiome relationship is complex in that microbes can confer symbiotic benefits to the host in multiple aspects of life that are important for maintaining health. However, deficiencies in this complex interaction may also disturb this symbiotic relationship and cause pathology. Lately, gut microbiome has been the focus of much research because imbalances in the microbiome, known as dysbiosis, have been linked to numerous pathologies. Zhang and colleagues detected specific dysbiosis in the gut and oral microbiomes of patients with rheumatoid arthritis (RA), which was somewhat resolved after patients underwent treatment for RA. These researchers raise the possibility of using microbiome composition in the prognosis and the diagnosis of RA.
Ongoing studies aim to find similar correlations between gut microbiome and osteoarthritis (OA). The association between disruption in microbial-host balance and several ailments has raised the question of how the association between microbial-host balance and certain ailments can be artificially influenced to treat OA.
Probiotic supplementation has been suggested as a method to relieve inflammation and other symptoms in arthritic patients because of its effect on the human microbiome. The effect of glucosamine on the microbiome and OA has been studied and changes to the microbiome were noted in culture in work by Coulson and colleagues. With the development of NGS, stronger correlations could be noted. Recent studies, such as one by Hieken and colleagues, suggest the microbiome is present in aseptic, deep breast tissue. This is a fascinating discovery, as it suggests that microorganisms — which do not communicate with the outside world — may inhabit organs that were previously thought to be sterile. Furthermore, researchers have also found variability in the microbiome between healthy and diseased states, which could be a potential explanation for pathogenicity.
Given the ease with which peptic ulcer disease is treated with a handful of medications, the prospect of OA being of infectious etiology is certainly enticing. Death due to infectious diseases is continuously declining, according to the CDC, so it may be that infection still poses a burden, but in unknown ways. Hopefully, clearer answers will come to light as the next frontier in medicine is crossed.
- CDC. https://www.cdc.gov/mmwr/preview/mmwrhtml/mm4829a1.htm. Accessed: Feb. 24, 2017.
- Coulson S, et al. Inflammopharmacology. 2013;doi:10.1007/s10787-012-0146-4.
- Hieken TJ, et al. Sci Rep. 2016:doi:10.1038/srep30751.
- Zhang X, et al. Nat Med. 2015;doi:10.1038/nm.3914.
- For more information:
- Javad Parvizi, MD, FRCS, can be reached at The Rothman Institute at Thomas Jefferson University Hospital, Sheridan Building, Suite 1000, 125 S. 9th St., Philadelphia, PA 19107; email: firstname.lastname@example.org.
- Noam Shohat, MD, can be reached at Department of Orthopedic Surgery, Assaf Harofeh Medical Center, Zerifin, Israel; email: email@example.com.
- Majd Tarabichi, MD, can be reached at The Rothman Institute at Thomas Jefferson University Hospital, Sheridan Building, Suite 1000, 125 S. 9th St., Philadelphia, PA 19107; email: firstname.lastname@example.org.
Disclosures: Parvizi reports he is a paid consultant for Zimmer Biomet, ConvaTec, TissueGene, CeramTec and Ethicon; has stock options with Parvizi Surgical Innovations, Hip Innovation Technology, CD Diagnostics, CorenTec, Alphaeon, Joint Purification Systems, Ceribell, MedAp, MicroGenDx, Cross Current Business Intelligence, Invisible Sentinel, Physician Recommended Nutriceuticals and Intellijoint; receives royalties from CorenTec, Datatrace, Elsevier, Jaypee, SLACK Incorporated and Wolters Kluwer. Shohat and Tarabichi report no relevant financial disclosures.