Crown-of-Thorns Envenomation

In the journal Wilderness & Environmental Medicine (Volume 19, Number 4, page 275), published by the Wilderness Medical Society, I am coauthor with Drs. Brian Lin and Robert Norris of an article entitled, "A Case of Elevated Liver Function Tests After Crown-Of-Thorns (Acanthaster planci) Envenomation." The article describes the clinical presentation and treatment of a young woman for whom we cared after she stepped on a crown-of-thorns sea star. The unique nature of her case was a transient elevation in her liver function tests ("liver enzymes"), which indicated toxicity or inflammation, attributed most likely to the effect of the venom released into her system from the spines.

The crown of thorns starfish (Acanthaster planci) is a particularly venomous starfish found in tropical oceans worldwide (figure 193). It carries sharp and rigid spines that may grow to 3 inches (7.5 centimeters) in length. The cutting edges easily penetrate a diver’s glove and cause a very painful puncture wound with copious bleeding and slight swelling. When a person steps on one of these creatures, as did our particular patient, the tips of the spines may be broken off into the skin. Multiple puncture wounds may lead to vomiting, swollen lymph glands, and brief muscle paralysis. Very importantly, the pain can be extremely severe, seemingly out of all proportion to the size of the (small) puncture wounds.

The treatment is similar to that for a sea urchin puncture. Immerse the wound in nonscalding hot water to tolerance (110 to 113° F or 43.3 to 45° C) for 30 to 90 minutes. This frequently provides pain relief, but severe pain may persist or worsen when the hot water immersion is discontinued. Administer appropriate pain medicine. Carefully remove any readily visible spines. If there is a question of a retained spine(s) or fragment(s), seek the assistance of a physician. Sometimes it is necessary to surgically remove the spines.

If the wound shows signs of infection (extreme redness, pus, swollen lymph glands) within 24 to 48 hours after the injury, or if the spine is felt to have penetrated into a joint, start the victim on an antibiotic to oppose Vibrio bacteria (e.g., ciprofloxacin, trimethoprim-sulfamethoxazole, or doxycycline), as well as an antibiotic to oppose Staphylococcus bacteria (e.g., dicloxacillin or cephalexin). If methicillin resistant Staphylococcus aureus (MRSA) is a concern, then consider using trimethoprim-sulfamethoxazole as the first antibiotic.

If a spine puncture in the palm of the hand results in a persistent swollen finger without any sign of infection (fever, redness, swollen lymph glands in the elbow or armpit), then it may become necessary to treat the victim with a 7-day course of oral prednisone in a tapering dose. The “average” dose for a 150 lb (68 kg) male is to begin with 70 mg and decrease by 10 mg per day. Corticosteroids should always be taken with the understanding that a rare side effect is serious deterioration of the head (“ball” of the ball-and-socket joint) of the femur, the long bone of the thigh.

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