Not All Infectious Microorganisms Malign Human Immune System

The test was worth every penny; the genetic interrogation coaxed the excised heart valve to confess to having been infected with Tropheryma whipplei, that wily and elusive organism best known as the causative agent for the nasty imitator of rheumatologic illness, Whipple’s disease. So much for a prior diagnosis of seronegative RA, which eventually disappeared along with many of his other symptoms following a change in his antibiotic regimen. MDS has helped identify an infectious cause in many cases of meningoencephalitis and uveitis in a timely fashion.¹⁴ Long-term harm can be averted. No doubt, we may be hearing more about its potential utility in determining the cause of cerebritis in those situations when the differential diagnosis includes such conditions as Behçet’s disease, lupus or vasculitis.

Hindsight

Many years ago, I was interviewing for a junior faculty position when I was taken aback by the questioning of the interviewer, who wondered aloud why I considered my five years toiling in a laboratory studying immune mechanisms in RA to be a fruitful use of my time. “You would have been better off studying microbiology” was his retort to the look of consternation spreading across on my face. For years, I considered this to have been a flippant remark. Now, I am not so sure.

Simon M. Helfgott, MD, is associate professor of medicine in the Division of Rheumatology, Immunology and Allergy at Harvard Medical School in Boston.

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