More Bee Story

Jeremy Joslin, MD has left a new comment on your post "Question About a Bee Sting":

"Thanks for posting this very interesting case. Your blog really helps me learn through cases that I don't ordinarily see.

Dr. Auerbach, do you think this could be a Type 4 hypersensitivity reaction alone which is causing the drawn-out symptoms? Like you said, the inflammatory mediators alone could be causing all of these symptoms simply by mere proximity to all the fine hand structures.

While special ultrasonography would be a useful first line modality, if it's not available do you think MRI would be able to define the "knot" and give a hint as to which soft-tissue structure it is associated with?

To me it doesn't seem very likely that such a minute penetration of the skin could violate the nerve sheath."

These are terrific questions. It is possible that this might be a prolonged hypersensitivity reaction, but I have not been made aware of a type 4 hypersensitivity reaction associated with a bee sting. I have, however, seen a reaction that was quite similar to serum sickness associated with multiple stings afflicting a single victim.

Magnetic resonance imaging (MRI) might be useful to define a foreign body, but I am not aware of its use for a bee stinger. The stinger would have to have penetrated quite deeply to warrant this modality, and in my experience, a retained stinger leaves a trailing end at the surface.

Violating a "nerve sheath" would not be the problem here, but rather a "reactive" inflammatory response affecting the nerve or a tendon sheath. It is not uncommon to have the introduction of an animal or plant toxin in the vicinity of a tendon, and to have it become inflamed.

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

Tags: bee, bee sting, wilderness medicine, outdoor medicine, healthline

Labels: bee, bee sting

Permalink and Comments | | Email Post

Multiple Bee Stings

A reader writes (about bee stings): "But what can be done for a victim stung many times, but who is not having an allergic reaction? I imagine this venom begins to become systemically dangerous after around 2-300 stings (assuming 500 is a lethal threshold)."

The most common cause for dangerously low blood pressure (shock) after a bee sting is an allergic reaction to the venom. The chance for this to happen is greater after multiple stings than after a single sting.

With multiple stings, the venom burden and its direct physiological effects may cause severe illness. Low blood pressure (hypotension), abnormal heart rhythms, difficulty breathing, abdominal pain, and nausea and vomiting may all be features of this sort of a reaction.

Treatment consists of administration of epinephrine by injection for the allergic reaction, and intravenous infusion of fluid to fill the cardiovascular system and reverse the low blood pressure. If the heart is beating in an abnormal rhythm, it may be necessary to administer drugs to normalize the rhythm.

If a complicated immune system reaction develops, then it may be necessary for a physician to prescribe a glucocorticoid ("steroid") medication to suppress the reaction.

Preview the 25th Anniversary & Annual Meeting of the Wilderness Medical Society, which will be held in Snowmass, Colorado July 25-30, 2008.

Tags: bee, bee sting, wilderness medicine, outdoor medicine, healthline

Labels: bee, bee sting

Permalink and Comments | | Email Post

Question About a Bee Sting

A reader writes: "I was stung by bee on the palm of my hand and forefinger 6 weeks ago. My palm remains inflamed and swollen, which worsens as the day progresses; all joints remain tender. I have a small pebble-like knot under the skin approx 1/4" to 1/2" from where I was stung. I have been to 6 different doctors without receiving much explanation. I recently saw a hand specialist who diagnosed "trigger finger" brought on by the bee sting. Anyone ever heard of this? Is it possible that the tip of the stinger remained inside and migrated a bit from the sting site? Could the hard place be tissue forming around the stinger that may have remained inside? An E.R. nurse practitioner says it is possible that the stinger remains inside, however, my treating doctor says no way possible."

There are a number of possibilities here, related to the pathophysiology of a bee sting. Depending on the species of bee, part or all of the stinger may have been present in the wound immediately after the sting. For instance, a honeybee often leaves the stinger and attached venom sac in the wound. Sometimes the stinger is easily visible, revealed as a tiny dark splinter or speck. Other times, it is impossible to see without magnification. So, unless the sting site was very carefully inspected under magnification and no stinger seen, something may have remained in the wound. This is not usually the case, but it happens.

Bee venom contains a number of components that cause pain, redness, and swelling, all of which can be part of the initial toxic envenomation and subsequent inflammatory response. Depending upon how close the sting was to a tendon (and its sheath, within which it slides), it could have caused tenosynovitis, which could cause persistent pain on motion, and ultimately lead to some contraction of the finger, which might be diagnosed as a “trigger finger.”

The formation of a knot might represent inflammatory tissue solidifying into a scar around the initial puncture wound, which would be more likely if there was a residual “foreign body.” The remaining material doesn’t need to be a huge piece – even a microscopic speck is enough to fuel the process. The material under the skin would not migrate to a different location, unless it was within an open tract, which is highly unlikely. So, is it possible that a fragment of the stinger is still within the tissue? The answer is yes. It might be visible using an enhanced ultrasound technique, so that might be worth a try.

Tags: bee, bee sting, wilderness medicine, outdoor medicine, healthline

Labels: bee, bee sting, foreign body

Permalink and Comments | | Email Post

Killer Bees in New Orleans

Africanized honey bees ("killer bees") have been identified in New Orleans, the furthest east that they have been found in the state of Louisiana. This is not an unexpected event, as this variety of stinging insect appears to be spreading across the United States and will likely eventually reside across the entire nation, unless contained by some environmental factor.

“Killer bees” are an Africanized race of honeybees created by interbreeding of the African honeybee Apis mellifera scutellata (brought for experiments into Brazil) with common European honeybees. The hazard from these bees is that they tend to be more irritable, sense threat at a distance greater than their European counterparts, swarm more readily, defend their nests more aggressively and stay agitated around the nest for days, and impose mass attacks upon humans. The venom of an Africanized bee is not of greater volume or potency than that of a European honeybee. However, the personality of the Africanized bees is such that they may pursue a victim for up to 2/3 mile (1 km), and may recruit other attacking bees by the hundreds or thousands. A victim may be stung 200 to more than 1,000 times; it is estimated that 500 stings achieves the lethal threshold. The bees unfortunately appear to be adapting to colder temperatures.

The sting mechanism for a honeybee is composed of a doubly barbed stinger attached to a venom sac that pumps venom into the victim. When the bee attempts to escape after a sting, the stinger and sac remain in the victim (this kills the bee) and continue to inject venom. Thus, the honeybee can sting only once, whereas a wasp, with a smooth stinger that does not become entrapped, can sting multiple times, as can yellow jackets, hornets, and bumblebees.

Pain from a bee, wasp, or hornet sting is immediate, with rapid swelling, redness, warmth, and itching at the site of the sting. Blisters may occur. Sometimes the victim will become nauseated, vomit, and/or suffer abdominal cramping and diarrhea. If the person is allergic to the insect venom, a dangerous reaction may follow rapidly (within minutes, but occasionally delayed by up to 2 hours). This consists of hives, shortness of breath, difficulty breathing, swelling of the tongue, weakness, vomiting, low blood pressure, and collapse. People have swallowed bees (undetected in beverage bottles) and sustained stings of the esophagus, which are enormously painful.

photo courtesy of library.thinkquest.org

Tags: bees, insect, killer bees, Louisiana, wilderness medicine, outdoor medicine, healthline

Labels: Africanized honey bee, bee, killer bee

Permalink and Comments | | Email Post