You are in: eMedicine Specialties >
Emergency Medicine > ENVIRONMENTAL
Stingray Envenomations
Article Last Updated: Sep 6, 2006
AUTHOR AND EDITOR INFORMATION
Section 1 of 11  
Author: John L Meade, MD, Chief of Emergency Medicine, Clinical Professor of Emergency Medicine, Pikeville College School of Os, Emergency Medicine, South Baldwin Regional Medical Center
John L Meade is a member of the following medical societies: American College of Emergency Physicians and Medical Association of the State of Alabama
Editors: Richard S Krause, MD, Clinical Assistant Professor, Residency Program Director, Department of Emergency Medicine, State University of New York at Buffalo School of Medicine; John T VanDeVoort, PharmD, ABAT, Director of Pharmacy, Sacred Heart Hospital; Richard Sinert, DO, Associate Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, State University of New York College of Medicine; Consulting Staff, Department of Emergency Medicine, Kings County Hospital Center; John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center; Scott H Plantz, MD, FAAEM, Assistant Professor, Research Director, Department of Emergency Medicine, Mount Sinai School of Medicine
Author and Editor Disclosure
Synonyms and related keywords:
marine, envenomations, stingrays, sting rays, elasmobranch, Dasyatidae, Potamotrygonidae, stingray, sting ray, fish injuries, beach injuries, stingray wound, stingray envenomation, stingray barb, stingray spine
Background
Stingrays (ie, elasmobranchs) are bottom-dwelling cartilaginous fish that have a flattened body, 1 or more stout spines on the tail, gill slits on the lower surface of the head, teeth modified into 2 large crushing plates, and no dorsal fin. They are not aggressive toward humans; however, injuries from these animals are very common.
Stingrays from the northern hemisphere make up the family Dasyatidae. These fish are marine creatures (ie, live in salt water) but also have been found in brackish waters and bays. Another ray family (Potamotrygonidae) contains poisonous species known as freshwater stingrays. These freshwater stingrays live in lakes and rivers of South America.
History
- Stingrays commonly are found lying half-buried in the sand or mud of coastal temperate areas.
- Injuries tend to occur when an unsuspecting person steps on the fish, causing the animal to reflexively strike the person with its defensive mechanism.
- The stingray's tail has 1 or more barbed stingers and 2 ventrolateral venom-containing grooves that are encased in an integumentary sheath. The tail is thrust into the victim, usually in the foot or lower leg, producing a deep jagged laceration from the serrated spine(s).
- The stinger apparatus then injects a protein-based toxin into the wound, causing immediate intense (even excruciating) pain in the victim. Injury may occur without envenomation because many stingrays lose or tear the integumentary sheath covering the venom glands.
- This subject has taken on new worldwide interest due to the unfortunate death of the celebrity wildlife naturalist Steve Irwin (also known as "The Crocodile Hunter") on September 4, 2006. Irwin was filming a documentary on stingrays in Queensland, Australia, when he reportedly suffered a puncture wound of the heart from a stingray barb. He died on the scene. This is a very rare injury since most stingray puncture wounds occur on the extremities and are not very deep.
Physical
- The wound may bleed freely and the patient may have systemic symptoms, including the following:
- Syncope
- Nausea
- Vomiting
- Diarrhea
- Diaphoresis
- Muscle cramps
- Fasciculations
- Abdominal pain
- Seizures
- Hypotension
Bites, Animal
Echinoderm Envenomations
Lionfish and Stonefish
Snake Envenomations, Sea
Lab Studies
- No laboratory studies are indicated in the usual case of stingray injury.
Imaging Studies
- Plain radiography should generally be used to obtain images of the injured area in at least 2 planes. Plain radiography is useful to rule out the presence of any foreign bodies, such as retained components of the barb mechanism, as well as to differentiate injuries caused by some other object (eg, sharp object stepped on in the water, causing a retained foreign body).
Prehospital Care
As soon as possible, immerse the affected body part in very hot water (as hot as the patient can tolerate without actually getting burned) or apply a hot pack to the affected body part. Heat rapidly decreases the patient's pain, presumably due to the direct effect on the poison.
Emergency Department Care
- If a patient has demonstrated any sign of systemic effect, it should be addressed quickly.
- No specific antidote is available, and supportive care is recommended, including use of analgesics.
- An easy and important initial treatment that can be started (sometimes at the scene of the injury) is immersion of the injured extremity in hot water (preferably 110-115°F). The water should be as hot as the patient can tolerate but should not cause burns. The water should be exchanged for more hot water as it cools, for an immersion duration of 30-90 minutes.
- Very little has been written about the toxin left in wounds after a stingray injury. It is known that the stingray toxin is a protein and is very sensitive to heat. The patient should obtain very rapid symptomatic improvement with heat as the poison denatures and becomes neutralized. Some thought exists that the protein does not truly denature but that some sort of gateway effect occurs on the nerve conduction. Whatever the truth is regarding how heat works, it is a rapid, effective treatment to reduce pain almost instantaneously.
- In addition, some practitioners also infiltrate the wound with a local anesthetic, such as lidocaine (lignocaine) or the longer-acting bupivacaine. Occasionally, oral or parenteral narcotics may also be given.
- After the toxin has been deactivated by the hot water, attention to local wound care should begin because it is not uncommon for part of the stinging apparatus to break off in the wound.
- Obtain a plain radiographic image of the injured area to look for retained barbs or other foreign material. Explore the wound thoroughly and irrigate it. Perform any necessary debridement.
- Remove any foreign body from the wounds, including the spine and sheath from the stingray stinger, as well as dirt or sand.
- As with other potentially contaminated wounds, consider allowing the wound to heal without closure. Because most of the wounds are small, this usually is not an issue. If the wound is very large or gaping, consider loose primary closure.
- Address the patient's tetanus immunization status and administer a booster as needed.
Infection is not common but, if it occurs, is likely to result in high morbidity because of injury location and the possible infecting agents in the water environment. Staphylococci and streptococci remain the most common infecting agents and must not be ignored. However, pathogens of specific concern to such envenomations are Vibrio species in saltwater and Aeromonas species in freshwater. Optimal coverage should include staphylococci, streptococci, and pathogens expected in the involved water (freshwater or saltwater). Such antibiotics include quinolones (eg, ciprofloxacin, levofloxacin), doxycycline, trimethoprim/sulfamethoxazole (Bactrim, Septra), cefuroxime or other late-generation cephalosporins, an aminoglycoside, or chloramphenicol. Many physicians choose to treat stingray envenomations prophylactically with a short course (~5 d) of oral antibiotics.
Drug Category: Antibiotics
Used in the treatment of uncomplicated infections and wound prophylaxis. Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in the context of the clinical setting.
| Drug Name | Levofloxacin (Levaquin) |
|---|
| Description | First line for infections caused by Vibrio species found in saltwater. Indicated for Staphylococcus aureus and infections caused by multidrug resistant gram-negative organisms. |
|---|
| Adult Dose | 250-500 mg PO qd for 5 d |
|---|
| Pediatric Dose | <18 years: Not recommended
>18 years: Administer as in adults |
|---|
| Contraindications | Documented hypersensitivity |
|---|
| Interactions | Antacids, iron salts, and zinc salts may reduce serum levels; administer antacids 2-4 h before or after taking quinolones; cimetidine may interfere with metabolism of quinolones; levofloxacin reduces therapeutic effects of phenytoin; probenecid may increase levofloxacin serum concentrations; may increase toxicity of theophylline, caffeine, cyclosporine, and digoxin (monitor digoxin levels); may increase effects of anticoagulants (monitor PT) |
|---|
| Pregnancy | C - Safety for use during pregnancy has not been established.
|
|---|
| Precautions | In prolonged therapy, perform periodic evaluations of organ system functions (eg, renal, hepatic, hematopoietic); adjust dose in renal function impairment; superinfections may occur with prolonged or repeated antibiotic therapy |
|---|
| Drug Name | Cefixime (Suprax) |
|---|
| Description | By binding to one or more of the penicillin binding proteins, it arrests bacterial cell wall synthesis and inhibits bacterial growth. An advanced-generation cephalosporin. Advantages include once-per-day dosing schedule and broad spectrum. A disadvantage is relatively high cost. |
|---|
| Adult Dose | 400 mg/d PO qd or divided q12h for 5 d |
|---|
| Pediatric Dose | <12 years: 8 mg/kg/d susp PO qd or 4 mg/kg bid
>50 kg or >12 years: Administer as in adults |
|---|
| Contraindications | Documented hypersensitivity |
|---|
| Interactions | Coadministration with aminoglycosides increases nephrotoxicity; probenecid may increase effects of cefixime |
|---|
| Pregnancy | B - Usually safe but benefits must outweigh the risks.
|
|---|
| Precautions | Adjust dose in renal impairment |
|---|
| Drug Name | Cephalexin (Keflex) |
|---|
| Description | First-generation cephalosporin, which is usually effective against Staphylococcus and Streptococcus species. Inexpensive and readily available, but has no real efficacy against Vibrio species. |
|---|
| Adult Dose | 250-1000 mg PO q6h for 5d or 500 mg PO q12h; not to exceed 4 g/d |
|---|
| Pediatric Dose | 25-50 mg/kg/d PO q6h; not to exceed 3 g/d |
|---|
| Contraindications | Documented hypersensitivity |
|---|
| Interactions | Coadministration with aminoglycosides increases nephrotoxic potential |
|---|
| Pregnancy | B - Usually safe but benefits must outweigh the risks.
|
|---|
| Precautions | Adjust dose in renal impairment |
|---|
| Drug Name | Doxycycline (Bio-Tab, Doryx, Vibramycin) |
|---|
| Description | Inhibits protein synthesis and, thus, bacterial growth by binding to 30S and, possibly, 50S ribosomal subunits of susceptible bacteria. Covers Vibrio species well, although coverage not as good for Staphylococcus and Streptococcus species. Generic versions are inexpensive. |
|---|
| Adult Dose | 100 mg PO bid for 5 d |
|---|
| Pediatric Dose | <8 years: Not recommended
>8 years: 2-5 mg/kg/d PO in 1-2 divided doses; not to exceed 200 mg/d |
|---|
| Contraindications | Documented hypersensitivity; severe hepatic dysfunction |
|---|
| Interactions | Bioavailability decreases with antacids containing aluminum, calcium, magnesium, iron, or bismuth subsalicylate; tetracyclines can increase hypoprothrombinemic effects of anticoagulants; tetracyclines can decrease effects of oral contraceptives, causing breakthrough bleeding and increased risk of pregnancy |
|---|
| Pregnancy | D - Unsafe in pregnancy
|
|---|
| Precautions | Photosensitivity may occur with prolonged exposure to sunlight or tanning equipment; reduce dose in renal impairment; consider drug serum level determinations in prolonged therapy; tetracycline use during tooth development (last one-half of pregnancy through age 8) can cause permanent discoloration of teeth; Fanconilike syndrome may occur with outdated tetracyclines |
|---|
| Drug Name | Trimethoprim and sulfamethoxazole (TMP-SMZ, Bactrim, Septra) |
|---|
| Description | Inhibits bacterial growth by inhibiting synthesis of dihydrofolic acid. Inexpensive combination agent that covers Vibrio and some Staphylococcus and Streptococcus species.
As with doxycycline, many individuals can develop photosensitive skin rashes while on the medication. (This is important if the patient is on vacation or lives at the beach and is likely to get significant sun exposure while on the medication.) |
|---|
| Adult Dose | 1 DS (double strength) tab PO bid or 2 regular strength tab PO bid or 20 mL susp PO bid for 5 d |
|---|
| Pediatric Dose | <2 months: Not recommended
>2 months: 8-12 mg/kg/d PO based on TMP divided bid (40 mg/5 mL susp) |
|---|
| Contraindications | Documented hypersensitivity; megaloblastic anemia because of folate deficiency; pregnant women at term and breastfeeding women (sulfonamides pass through placenta and are excreted in breast milk, which may cause kernicterus) |
|---|
| Interactions | May increase PT when used with warfarin (perform coagulation tests and adjust dose accordingly); coadministration with dapsone may increase blood levels of both drugs; coadministration of diuretics increases incidence of thrombocytopenia purpura in elderly persons; phenytoin levels may increase with coadministration; may potentiate effects of methotrexate in bone marrow depression; hypoglycemic response to sulfonylureas may increase with coadministration; may increase levels of zidovudine |
|---|
| Pregnancy | C - Safety for use during pregnancy has not been established.
|
|---|
| Precautions | Discontinue at first appearance of rash or sign of adverse reaction; obtain CBCs frequently; discontinue therapy if significant hematologic changes occur; goiter, diuresis, and hypoglycemia may occur with sulfonamides; prolonged IV infusions or high doses may cause bone marrow depression (if signs occur, give 5-15 mg/d leucovorin); caution in folate deficiency (eg, chronic alcoholic persons, elderly individuals, those receiving anticonvulsant therapy, or people with malabsorption syndrome); hemolysis may occur in G-6-PD deficiency; AIDS patients may not tolerate or respond to TMP-SMZ; caution in renal or hepatic impairment (perform urinalyses and renal function tests during therapy); give fluids to prevent crystalluria and stone formation |
|---|
Further Outpatient Care
- Give patients explicit instructions regarding attention to local wound care and advise them to watch for infection. Requesting that the patient seek a wound check in 2-3 days (with a family doctor or at the ED) is not unreasonable.
- It is especially vital that the patient understands that for any sign of infection with Vibrio organisms, time is of the essence in returning to the ED for immediate care.
In/Out Patient Meds
- Prescribing oral narcotics for patients to use as needed upon discharge is appropriate.
Deterrence/Prevention
- When stepped on, the stingray reflexively strikes out, causing the injury to the person who stepped on it. Advise patients to walk in the shallow areas of the beach with a shuffling gait. This is effective in causing stingrays to move away and help decrease the possibility of accidentally stepping on a stingray.
Prognosis
- Stingray injuries (eg, puncture wounds, lacerations, envenomations) tend to have good outcomes. If patients do not develop infection or other complications, they can expect to have minimal pain in 24-48 hours and healing within 1-2 weeks.
Patient Education
- The following is an example of a discharge instruction sheet that could be given to patients after treatment for stingray injuries:
- Because so many areas of water are nearby, many types of injuries associated with being in or near the water are encountered. These injuries may occur while fishing, walking on the beach, playing in the surf, diving, or working with a home aquarium.
- Stingrays often cause lacerations and puncture wounds when the tail whips up and thrusts its spines into the victim, injecting venom (poison). The pain is severe immediately and worsens over the next hour. The pain may last 48 hours. Although rare, deaths have occurred from stingray injuries.
- As soon as possible, the wound should be soaked for 30-90 minutes in very hot water (as hot as can be endured without causing burns). The heat inactivates the poison and dramatically relieves the pain. The physician may prescribe pain medication. Also, because the risk of infection is very high, antibiotics are given to prevent infection.
- Despite the best of care, any wound can develop infection or other complications. If any of the following occur, it is recommended that patients call their own doctor, the referral physician, or clinic. If a physician cannot be contacted, return to the ED is advised:
- Wound drainage increases, shows pus, or develops a foul odor
- Wound bleeds heavily
- Wound becomes more sore or swollen
- Wound develops increasing redness, or red streaks develop
- A fever develops
- Wound does not appear to be healing properly
- Any other new or worsening symptoms that are of concern.
- For excellent patient education resources, visit eMedicine's Bites and Stings Center. Also, see eMedicine's patient education article
Stingray Injury.
Medical/Legal Pitfalls
- Review the radiographs and examine the wound carefully, looking for retained foreign bodies. Portions of the stingray spine, barbs, or integumentary sheath could be within the wound. If not removed, infection and complications are likely.
- Remember the potential for infection, and strongly consider antibiotic coverage, if only for a few days.
| Media file 1:
Typical stingray puncture wound on a foot, approximately 60 minutes after injury.(Photo by John L. Meade, MD) |
 |  View Full Size Image | |
Media type: Photo
|
| Media file 2:
Stingray barb in forearm.(Photo by John L. Meade, MD) |
 | View Full Size Image | |
Media type: Photo
|
| Media file 3:
Stingray barb broken off in ring finger. (Photo by John L. Meade, MD) |
 | View Full Size Image | |
Media type: X-RAY
|
| Media file 4:
Spine removed from stingray injury. (Image courtesy of Scott Plantz, MD) |
 | View Full Size Image | |
Media type: Photo
|
- Campbell J, Grenon M, You CK. Pseudoaneurysm of the superficial femoral artery resulting from stingray envenomation. Ann Vasc Surg. Mar 2003;17(2):217-20. [Medline].
- Ellenhorn MJ. Envenomations: bites and stings. In: Ellenhorn's Medical Toxicology. 2nd ed. Lippincott Williams & Wilkins;1997:1737-98.
- Fenner PJ, Williamson JA, Skinner RA. Fatal and non-fatal stingray envenomation. Med J Aust. Dec 4-18 1989;151(11-12):621-5. [Medline].
- Guenin DG, Auerbach PS. Trauma and envenomations from marine fauna. In: Tintinalli JE, et al, eds. Emergency Medicine: A Comprehensive Study Guide. McGraw-Hill;1996:868-73.
- Otten EJ. Venomous animal injuries. In: Rosen P, et al, eds. Emergency Medicine: Concepts and Clinical Practice. Mosby-Year Book;1998:924-40.
- Perkins RA, Morgan SS. Poisoning, envenomation, and trauma from marine creatures. Am Fam Physician. Feb 15 2004;69(4):885-90. [Medline].
- de Haro L, Pommier P. Envenomation: a real risk of keeping exotic house pets. Vet Hum Toxicol. Aug 2003;45(4):214-6. [Medline].
Stingray Envenomations excerpt Article Last Updated: Sep 6, 2006
|
