Inflammatory Origin of Fever Is Key to Diagnosis

In addition to the spectrum of periodic fever syndromes, the autoinflammatory diseases cast a wide net and include granulomatous disorders, such as sarcoidosis and Blau syndrome; storage diseases, such as Gaucher’s; Behçet’s disease; the crystalline arthropathies, such as gout and pseudogout; and adult Still’s disease, to name a few. In the course of just a decade, such terms as inflammasome, cryoprin and danger signals have become commonplace in the rheumatologist’s vocabulary.

Following The Silk Road

For years, clinicians have been intrigued by the curious geographic distribution of Behçet’s disease (BD). Its highest prevalence occurs across Asia in countries between 30° and 45° latitude north, where the disease runs a more severe course than in other parts of the world.10 One explanation for the unusual geographical distribution of BD is that a genetic risk factor may have been propagated through previously isolated communities by itinerant traders or earlier pastoral nomads whose path across Asia was determined by the natural geographic features of the continents. The most likely path they traveled would have been the Silk Road.

Silk was a highly valuable commodity. It was a key product in the Chinese economy, and controlling its availability made silk a valuable tool of China’s foreign policy. The traditional founder of the Silk Road is considered Zhang Qian, a courtier dispatched westward in 121 BC to bring back the unusually powerful horses, which roamed in present-day Uzbekistan. A trail heading westward from China was started, and over the centuries, traders extended it all the way to the Mediterranean Sea.¹⁰

Whenever I think of the Silk Road, I recall my patient Monique. I saw her for the last time about a year following her total hip replacement surgery. She was feeling well. Her hectic fevers had resolved. She told me that she still had the travel bug and was hoping to visit China and Tibet one day. I wonder if she ever took that trip.

Simon M. Helfgott, MD, is associate professor of medicine in the division of rheumatology, immunology and allergy at Harvard Medical School in Boston.

Note (10/19/2014): In the editorial above, I should have credited the seminal research of Daniel Kastner MD, PhD, senior investigator, Metabolic, Cardiovascular and Inflammatory Disease Genomics Branch, and head, Inflammatory Disease Section, whose numerous scientific contributions established the field of autoinflammatory disease, a term he coined.

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