Doctor Gets Plant Thorn Arthritis (cont.)

I gently removed the two thorns and was hopeful that all would be well. Understand that having a thorn in tissue like the finger is usually not a serious problem. Also understand that having any remnants of thorn within a joint is a very serious problem.

Over the next day, the finger was fine, but the knuckle joint became slightly reddened. It did not hurt. The redness resolved within 48 hours and I attributed it to either blood inflammation from the trauma of the thorn, inflammation from the resin on the thorn, or both.

My hand was normal for the subsequent four days. After this "delay period," it then became stiff and swollen. At that time, a first order of concern was the possibility of bacterial or fungal infection in the joint. Accordingly, I consulted with my three partners, Catherine Driver, MD, Al Wehrle, MD, and Hernan Castro-Rueda, MD. They all agreed that I should have fluid removed from the joint immediately for culture and analysis and take an anti-inflammatory medication for pain and swelling. I also took an antibiotic until the bacterial cultures returned. Al very skillfully removed the fluid with a needle and syringe and I took it to the hospital laboratory for study. The fluid was full of an abnormally high amount of white blood cells but had no bacteria or fungus growing in it. (The actual bacteria culture takes three days and the fungus culture takes four weeks.)

When all cultures returned "no growth," because of persisting swelling and stiffness of the joint, I suspected that I had tiny thorn remnants within the joint. This is in spite of the fact that radiology imaging studies did not detect a thorn fragment. Also, the swelling of the joint did not have the appearance of what I was familiar with in cases of bacterial infection. With bacterial arthritis of a joint (septic arthritis), the joint is very hot, very red, and very painful. There is often accompanying inflammation of the adjacent skin tissues. My joint, however, was not perceptibly warm and was stiff but not really painful. These features as well as the delay period of nearly a week from the initial thorn puncture until developing the arthritis are classic features of plant thorn arthritis.

I must at this point explain that I am an arthritis expert (a rheumatologist) and, while I had known about plant thorn arthritis, I had never seen a case. The development of the inflammation in the joint of plant thorn arthritis is a slow process that involves certain immune cells that gradually accumulate in the joint lining tissue (synovium). This immune response to the foreign material (thorn matter) within the joint is referred to as a foreign body granulomatous reaction. It is not as acutely inflamed with warmth and redness as is a bacterial infection, but it is just as dangerous and destructive to the joint, although slower. There is only one treatment for this form of arthritis -- surgically removing the inflamed tissue and all plant matter within the joint.