He learned everything he could about the microorganisms that cause bone and joint disease, namely bacteria, viruses, fungi, parasites and Mycoplasmas. Bacterial infections were known to cause septic and reactive arthritis. Multiple viruses were implicated in arthritis while some frequently caused it. Species of fungi were known to be pathogens that could lead to arthritis and parasites had been associated with joint and bone lesions. The role Mycoplasma played in arthritis, however, had been debated for years.
Mycoplasma species differ from bacteria in that they are very small and lack a cell wall.
They are the smallest organism able to survive outside of cells. They enter the tissue in different areas and cause injury to the cell mucosa. Once damage to the body occurs, the body frequently is unable to clear the Mycoplasma from the site of infection without antimicrobial treatment. With all that was known about the causes of rheumatalogic diseases, Dr. Franco was frustrated and baffled that the treatments for these ailments were not more effective. Ever curious, he wanted to know why.