The phylum Echinodermata includes a diverse group of marine animals that are slow moving and nonaggressive, including brittle stars (class Ophiuroidea), starfish (class Asteroidea), sea urchins (class Echinoidea), and sea cucumbers (class Holothuroidea). These animals have pentamerous (5-part) radial symmetry and calcareous skeletons that form thick outer plates and protective spines in some; hence, they are named Echinodermata, which means spiny skin. Injury and envenomation occur almost exclusively from accidental contact or careless handling; bathers, divers, and fishermen are at greatest risk.[1] Poisonous echinoderm ingestions or intoxications are not covered in this article. See the image below.
View Image | Echinoderm envenomations. Unlike most starfish that are typically pentamerous, the crown-of-thorns starfish (Acanthaster planci) may have as many as 2.... |
See Deadly Sea Envenomations, a Critical Images slideshow, to help make an accurate diagnosis.
While most echinoderms are poisonous, and many have sharp spines or spicules capable of causing injury, only a few members of the Asteroidea, Echinoidea, and Holothuroidea classes are capable of causing venomous injuries in humans. In this article, envenomation refers to the parenteral or topical application of toxins produced in specialized glands and tissues with modified application structures (spines, pedicellaria, tentacles). This definition is in contrast to poisoning or intoxication, which refers to the oral ingestion of toxins produced or accumulated in nonspecialized glands or tissues.
Brittle stars (class Ophiuroidea; see the image below) are not generally considered capable of causing venomous injuries in humans.
View Image | Echinoderm envenomations. Close-up of brittle star arm. Although spiny, members belonging to this class (Ophiuroidea) generally are considered harmles.... |
However, some brittle stars (Ophiomastix annulosa) do possess toxins and are capable of causing paralysis and death in small animals. These animals should be handled with care.
Starfish (Asteroidea) envenomation in humans is well described, with the crown-of-thorns starfish (Acanthaster planci) as the main culprit (see the images below).
View Image | Echinoderm envenomations. Detail of the crown-of-thorns starfish (Acanthaster planci) spines, which may grow to 6 cm in length. Photo courtesy of Dee .... |
View Image | Echinoderm envenomations. Detail of the crown-of-thorns starfish (Acanthaster planci). Photo courtesy of Scott A. Gallagher, MD. |
Acanthaster species possess long (5-6 cm), extremely sharp spines projecting from the dorsal surfaces of their bodies and numerous arms (7-23, a notable exception to the usual 5 arms). These spines are covered with a 3-layered integument that, in turn, is associated with glandular cells that produce a variety of toxins. Rupture of the overlying integument during spine penetration results in release of a range of bioactive substances capable of causing local and generalized toxicity in humans. Other starfish potentially capable of envenomation include members of the genus Echinaster, which possess thorny spines and small pits from which toxins are secreted, and Plectaster and Solaster species, which are reported to cause contact dermatitis.
Sea urchins (Echinoidea) capable of causing venomous injuries in humans use specialized spines (long or short) and pedicellaria (delicate seizing organs equipped with pincerlike jaws) to deliver their venom. Although both structures are present, generally only one is venomous in a given species. Thus, grouping the venomous urchins into one of the following three categories is convenient:
Long-spined species may inject venom during a puncture with rupture of the overlying integument (Diadema species; see the image below) or with fracture and release of venom from hollow-lumen spines (Echinothrix species).
View Image | Echinoderm envenomations. Long-spined sea urchins, such as this Diadema species, inflict an acutely painful penetrating injury that may be accompanied.... |
Short-spined species similarly may envenom during puncture when downward pressure ruptures the surrounding integument (Phormosoma species), or they may deliver a severe sting without puncture via venom glands located at the spine tips (Asthenosoma species, Araeosoma species).
Species with pedicellaria include those reputed to be the most venomous of all sea urchins, the flower urchin (Toxopneustes pileolus), and others that are less venomous (Tripneustes species). Pedicellaria are small, delicate, tripled-jawed seizing organs that are supported by a long stalk and interspersed among numerous nonvenomous spines. Fanglike appendages are associated with venom glands at the tips of each jaw. The fangs are capable of penetrating skin and may be difficult to dislodge because the valve muscles tightly close each jaw. Pedicellaria continue envenoming even when detached from the urchin body and, thus, should be removed promptly.
Sea cucumbers (Holothuroidea) are generally regarded as nonvenomous, although many are poisonous to eat without proper preparation. The Cuvierian tubules of some sea cucumbers are toxic and may be extruded from the anus as a defensive mechanism when the animal is disturbed or irritated (Bohadschia argus; see the image below).
View Image | Echinoderm envenomations. The common and toxic sea cucumber, Bohadschia argus, with extruded Cuvierian tubules. Contact with these sticky white tentac.... |
According to some sources, skin contact may trigger a vigorous inflammatory reaction.[2, 3] However, other experts attest to island customs in which Cuvierian tubules are applied for the relief of coral cuts (A. M. Kerr, Yale University, written communication, March 1999; G. Paulay, Guam University, written communication, March 1999). Accounts of blindness following eye contact are poorly substantiated,[4] although intense conjunctivitis or keratitis may occur.
United States
Echinoderm envenomations do not represent a significant public health problem, although little epidemiologic data are available. Venomous echinoderms are encountered principally in tropical seas. Nonvenomous traumatic injuries from echinoderms are not uncommon in the United States, especially in coastal communities where sea urchins live.
International
Echinoderm envenomations are quite common, although little epidemiologic data are available.
The most common starfish envenomization results from contact with the crown-of-thorns starfish (Acanthaster planci), which populates reefs of the Indo-Pacific from east Africa to Central America. Similarly, sea urchins capable of envenomation tend to be concentrated in tropical and subtropical marine regions. The Indo-Pacific is the home of all categories of venomous urchins, including Diadema, Echinothrix, and Toxopneustes species and the venomous genera of sea cucumbers (Holothuria). For some Chinese, Malay, and Pacific Island gourmets, properly prepared sea cucumbers are prized as a delicacy (eg, beche-de-mer, trepang).
Significant local and systemic effects are possible following echinoderm envenomation from any of the three venomous classes, starfish (Asteroidea), sea urchins (Echinoidea), and sea cucumbers (Holothuroidea). However, a clear link between echinoderm envenomation and death (other than subsequent drowning) cannot be found in the literature, despite several anecdotal reports of fatalities.[3, 5, 6, 7] Detailed documentation is sparse, and death must be very rare. This is in contrast to poisoning or intoxication following ingestion of certain echinoderms, which has been well documented to result in severe illness and fatality.
For patient education resources, visit the Infections Center, Skin Conditions and Beauty Center, and First Aid and Injuries Center. Also, see the patient education articles Tetanus, Bruises, and Stingray Injury.
Immediate and often incapacitating pain is described following puncture wounds from the crown-of-thorns starfish (Acanthaster planci), long-spined urchins (Diadema species, Echinothrix species), and some short-spined urchins (Phormosoma species). Similarly, pedicellaria-containing urchins (Toxopneustes species, Tripneustes species) and other short-spined urchins (Asthenosoma species, Araeosoma species) may deliver a severe sting at the slightest touch without inflicting any puncture at all. Significant ocular inflammation, dermatitis, and pain may follow topical exposure to the holothurin toxins of venomous sea cucumbers.
Envenomation begins with penetration of the skin with the long remarkably sharp dorsal spines. Usually, but not invariably, immediate excruciating burning pain is experienced at the puncture site. Divers are reportedly at risk of unsafe ascent, disorientation, and loss of control because of the intense pain. A single puncture may result in several hours of pain, while multiple or intraarticular punctures may lead to pain, discomfort, and limitation of joint movement for several weeks.
Bleeding at the puncture site may be prolonged in some patients and is followed by surrounding ecchymosis and soft tissue swelling. Systemic symptoms of protracted nausea and vomiting, headache, arthralgias, paresthesias, and muscular paralysis are less substantiated than the other symptoms described but, nevertheless, are reported in several texts. Case reports of edema and pruritus suggest the possibility of allergic reaction, although no reports of anaphylaxis or fatality are mentioned.
Common complications result from retained foreign material and include secondary infection and granuloma formation.
The mechanism of envenomation varies among the 3 groups.
Long-spined urchins (Diadema species, Echinothrix species) are capable of causing deeply penetrating injuries. Envenomation initially results in severe burning pain, which is localized to the puncture site and may last several hours, reappearing with any pressure on the wound site. Localized edema, erythema, warmth, and bleeding may follow. The systemic symptoms of nausea, vomiting, paresthesias, muscular paralysis, and respiratory distress occur in the most severe cases. Delayed sequelae include wound tattooing as pigment is leeched from dark-colored spines into the surrounding tissue, synovitis if a joint space is violated, and secondary wound infection or granuloma formation if foreign material is retained.
Some short-spined urchins have spines tipped with balloonlike venom sacs that are capable of delivering a severe sting without inflicting a penetrating wound (Asthenosoma species, Araeosoma species), while others envenom in a fashion similar to long-spined urchins, releasing venom into the wound when the spine penetrates the skin (Phormosoma species).
Urchins with pedicellaria may envenom following simple handling if sufficient contact occurs. The flower sea urchin (Toxopneustes pileolus) is reputedly the most venomous of urchins. Intense radiating pain, paresthesias, hypotension, respiratory distress, and muscular paralysis are potential sequelae of contact with this species and may last up to 6 hours. Reportedly, a female pearl diver became unconscious after accidental contact with the flower sea urchin and subsequently drowned.
Envenomation follows contact with the toxin-containing body wall or the organs of Cuvier, a mass of white, pink, or red tubules just inside the anus. In some species, long sticky threadlike organs may be extruded from the anus when the animal is disturbed. Direct contact with these organs, or even fragments released in close proximity to a diver, may induce a papular contact dermatitis, severe ocular inflammation, and, purportedly, blindness.
Similarly, toxic mucous secretions on sea cucumber skin can be a skin and eye irritant. These toxins, known as holothurins, also are elaborated in the body wall and, thus, are capable of causing severe illness or death upon ingestion.
The severity of envenomation depends on multiple factors, including the offending species; site and number of stings; the size, maturity, and age of the animal; and the underlying health and individual sensitivity of the individual exposed.
In addition to immediate pain, deep puncture wounds that accompany envenomation by crown-of-thorns starfish (Acanthaster species), long-spined urchins (Diadema species, Echinothrix species), and some short-spined urchins (Phormosoma species) often are associated with retained spine fragments and persistent discomfort. Violet or black discoloration of the wound may occur as pigment from dark-spined species (Diadema, Strongylocentrotus) leeches into the wound; this discoloration usually is not permanent. Bleeding, ecchymosis, surrounding erythema, edema, and even pruritus may follow spine puncture by Acanthaster species.
Complications arise when punctures occur in proximity to a joint space (eg, synovitis), nerves (eg, neuropathy), vessels (eg, hemorrhage), or when wounds become indolent, often because of retained spine fragments (eg, chronic pain, granuloma, secondary infection).
Nonpenetrating wounds result from envenomation by some short-spined urchins (Asthenosoma species, Araeosoma species) and pedicellaria-containing urchins (Toxopneustes species, Tripneustes species). Although the local complications that follow puncture wounds do not occur, significant pain and systemic effects result.
Sea cucumber envenomations similarly are not associated with puncture wounds. Contact with the venomous tentacular organs of Cuvier or dispersed fragments may result in severe dermatitis, conjunctivitis, keratitis, and, possibly, blindness.
A panoply of systemic effects has been described following echinoderm envenomations; they commonly include nausea, vomiting, paresthesias, generalized weakness, respiratory distress, and delirium. Claims of cardiac dysrhythmias, paralysis, and fatality are difficult to substantiate. The most severe echinoderm envenomations result from stings by the flower sea urchin (Toxopneustes pileolus) and have caused at least 1 death following loss of consciousness and subsequent drowning in a Japanese pearl diver.
No deaths are known to have resulted from the crown-of-thorns starfish (Acanthaster planci), although injury eventually resulting in leg amputation has been reported. Long-spined black sea urchins (thought to be Diadema species) have been implicated twice in severe neurologic sequelae, one case of meningoencephalitis and another of Guillain-Barré syndrome. The theoretic possibility of anaphylactic reaction to echinoderm venoms is entertained by some, although no cases have been documented to date.
Delayed sequelae include chronic pain, granuloma formation, wound tattooing, and secondary infection.
Tetanus may result following echinoderm envenomations accompanied by puncture wounds.
Echinoderms are slow moving and nonaggressive; injury and envenomation occur as the result of accidental exposure or careless handling.
Bathers, waders, and divers are at risk of stepping on or being forced against the sharp spines of venomous sea urchins and starfish, especially in waters with strong surges, currents, or poor visibility.
Fishermen and overly curious individuals often become envenomed through careless handling.
The sharp spines of venomous long-spined urchins, certain short-spined urchins, and starfish can easily penetrate wet suits and gloves. The stinging tips of other short-spined urchins and those with pedicellaria easily envenomate through exposed skin.
Sea cucumbers may induce severe contact dermatitis or ocular injury in divers following unprotected handling or mask clearing in close proximity to the animal.
No specific laboratory tests are indicated in the management of echinoderm envenomations; however, in cases of severe systemic symptoms (eg, hypotension, paralysis, respiratory failure), a complete workup to exclude other etiologies may be warranted.
Soft tissue radiographs are indicated as the initial study modality when attempting to exclude retained foreign bodies. Most calcareous spines are visualized either directly or indirectly with the use of radiographs. Nonradiodense objects can be revealed as filling defects or outlined by air drawn into the wound during the injury.
If an object cannot be visualized by plain radiography or retrieved easily through direct visualization, ultrasound may be used. Ultrasound can detect nonradiodense foreign bodies as small as 1 X 2 mm and can be used to accurately localize foreign material and provide guidance during removal. Tendons, deep scar tissue, fresh hematoma, and tissue calcifications can produce false-positive ultrasound readings. Ultrasonography requires experience and skill to maximize its usefulness.
Computed tomography (CT) scans and magnetic resonance imaging (MRI) are expensive alternatives to ultrasound that can identify and precisely localize retained foreign material. Both require a high degree of patient cooperation and may be difficult to perform on pediatric patients.
Ocular exposure to holothurin toxins and tentacular fragments following exposure to the organs of Cuvier of sea cucumbers requires a thorough slit lamp examination for retained foreign bodies and evidence of corneal abrasion or keratitis.
Prehospital care entails recognition of the injury as a potential envenomation, gentle removal of superficial spines and pedicellaria, direct pressure to control bleeding, administration of analgesia, and transport for medical evaluation.
Recognition of serious systemic symptoms and prompt institution of appropriate life-saving procedures, such as cardiopulmonary resuscitation (CPR) and treatment for anaphylaxis, should be paramount in the prehospital care setting. CPR and advanced cardiac life support (ACLS) are rarely indicated but always take absolute precedence.
While not universally endorsed, several sources recommend pressure immobilization as an early first aid measure for rare cases with suspected anaphylactic reaction. Apply a compression bandage to the affected limb to impede lymphatic flow at a pressure range of 40-70 mm Hg for upper extremities and 55-70 mm Hg for lower extremities (clinically equivalent to comfortable pressure that is neither too tight nor too loose). Immobilization via splinting should follow to limit muscular contraction and the resultant muscle pump effect. In the absence of serious generalized allergic reaction, pressure immobilization bandaging is strongly contraindicated and may be harmful.
Emergency department (ED) management of echinoderm envenomation involves addressing the venom exposure and the accompanying trauma inflicted by the specific application structures used to deliver the venom (spines, pedicellaria, tentacles). General rules of therapy include prompt analgesia, wound management, and observation for and supportive treatment of significant systemic symptoms.
Methods of recommended analgesia are variable but generally include initial treatment with hot water immersion followed by adjunctive local or regional anesthesia and parenteral analgesics, as needed.
Nearly all references recommend initial immersion in nonscalding hot water following the removal of visible spines and sheaths. Hot water immersion to inactivate heat-labile toxins is widely recommended as effective treatment for envenomations by echinoderms as well as stingrays, stonefish, and other venomous marine spine injuries. Immerse the affected limb in water not warmer than 114°F or 45°C.
Exercise caution not to inflict thermal burns by placing an insensate limb (as the result of local anesthesia or decreased sensitivity from pain) in scalding water. Others have noted that immersion in ice water also may provide relief. Local or regional anesthesia is a suggested means of adjunctive analgesia when immersion therapy does not provide sufficient pain relief. Local or regional adjunctive anesthesia offers several benefits, including no risk of inflicting thermal injury; reliable, prompt, and prolonged duration of analgesia; and simultaneous debridement of the wound while providing analgesia. Parenteral analgesics and/or sedatives may be needed for wounds that are difficult to anesthetize or persons who exhibit anxiety reaction to envenomation.
Wound management principles include identification of foreign material, adequate debridement, prophylactic antibiotics when indicated, tetanus prophylaxis, and appropriate referral for retained fragments that are not easily accessible in the ED.
Promptly undertake debridement of loose spines, spicules, and pedicellaria, taking care not to break brittle structures and create retained fragments. Immediate gentle removal of obviously protruding spines prevents further envenomation, penetration, or breakage.
Similarly, to prevent ongoing envenomation, remove all visible pedicellaria as soon as possible by applying shaving foam and gently scraping with a razor. Pull embedded debris straight out with forceps, taking care to avoid bending or jiggling spines that may break off at the tips.
Ultrasound or radiography can help identify retained fragments that may require referral for consideration of operative removal. Surgical removal with proper anesthesia of embedded spines is indicated when in proximity to joints, nerves, or vessels. Spines in weight-bearing surfaces may also require removal to prevent chronic pain.
Retained spine fragments may cause inflammation, become encapsulated, and develop granulomata during the healing process, leading to infection or chronic pain.
Most thin embedded spines are absorbed or extruded through the skin in days to weeks. Not all spines need be surgically removed. Copious irrigation to remove introduced foreign material always should be performed after adequate anesthesia.
Tetanus prophylaxis is indicated in all patients with traumatic marine injuries who have insufficient or uncertain immunization histories.
Ocular exposure to the holothurin toxins of sea cucumbers mandates a careful ophthalmologic examination. Following topical anesthesia, copiously irrigate and perform slit lamp examination to identify and address any retained tentacular fragments, corneal abrasions, or evidence of keratitis. Prompt ophthalmologic referral is indicated.
Systemic symptoms of envenomation are not uncommon and reportedly encompass a wide range of nonspecific symptoms, including nausea, vomiting, abdominal pain, malaise, arthralgias, paresthesias, muscular paralysis, respiratory distress, hypotension, syncope, and, rarely, death.
No antivenom for any of the venomous echinoderms exists. Treatment is supportive.
Although rare, some severe reactions may represent anaphylaxis and should be treated accordingly.
Consultation with an appropriate surgical specialist is advised for all complicated puncture wounds in proximity to articular and neurovascular structures. Spine extraction is best performed acutely and with an operating microscope in the surgical suite.
Plantar puncture wounds are potentially complicated injuries and may require consultation or referral for foreign material not easily extracted in the ED.
Consultation and admission to the general internist for supportive care may be warranted when symptoms of serious systemic envenomation are present. Protracted pain, nausea, muscular weakness, respiratory distress, and hypotension are a few systemic symptoms that may warrant care beyond the scope of the emergency department. Additionally, in the rare case of sepsis caused by Vibrio or Aeromonas species, a coordinated multispecialty effort is needed to address wound debridement, antibiosis, and critical care support.
Urgent ophthalmologic referral is appropriate in cases of ocular exposure to holothurin toxins.
Most injuries and envenomations caused by starfish and sea urchins result from inadvertently stepping upon or carelessly handling them. Wading in bare feet in turbid waters, especially at night, should be avoided. While shoes, diving booties, and wet suits may provide some protection, each is easily penetrated by the sharp long spines of the crown-of-thorns starfish and many species of urchin.
The use of thick gloves is recommended if one must handle the crown-of-thorns starfish or any of the sharp-spined sea urchins. This also applies to many sea cucumber species and short-spined sea urchins, particularly the flower urchin (Toxopneustes pileolus), that do not need to produce a puncture wound to envenomate.
The toxins contained in the body wall and white Cuvierian tubules extruded from the anus of some species of sea cucumber may cause significant ocular irritation. Therefore, divers should not clear their masks in close vicinity to a disturbed sea cucumber or touch their eyes after handling sea cucumbers.
Whether significant dermal irritation occurs after contact is debatable (conflicting data are available). Several sources report vigorous inflammatory reactions following direct skin contact with Cuvierian tubules and recommend against touching the white tubules extruded from the anus of some sea cucumbers. Other experts report extensive personal experience and island customs involving direct contact with no adverse effects.
Medical therapy is directed primarily at local and systemic analgesia, with nonspecific supportive therapy required only in the most severe cases. Prophylactic antibiotics are generally not indicated, except in persons with deep puncture wounds or who are immunocompromised. However, once infection is established, prompt therapy must be instituted with emphasis on coverage for potential marine pathogens. No antivenoms are available. Tetanus prophylaxis is indicated in all marine animal injuries.
Clinical Context: Any of the commonly used local anesthetics suffice; however, bupivacaine provides superior duration of anesthesia and pain relief for irrigation, wound exploration, and debridement.
These are used to provide local or regional anesthesia as adjunctive or alternative pain control.
Clinical Context: Morphine sulfate is the drug of choice for narcotic analgesia because of its reliable and predictable effects, safety profile, and ease of reversibility with naloxone. Morphine sulfate administered intravenously may be dosed in a number of ways and is commonly titrated until the desired effect obtained.
Analgesics are for adjunctive pain control when immersion therapy and local and/or regional anesthesia are not sufficient. Analgesic route (oral or parenteral) is a matter of choice and may not be needed with appropriate local or regional anesthetic.
Clinical Context: Trimethoprim-sulfamethoxazole inhibits bacterial synthesis of dihydrofolic acid by competing with PABA. This results in inhibition of bacterial growth.
Clinical Context: Ciprofloxacin is a bactericidal antibiotic that inhibits bacterial DNA synthesis and, consequently, growth, by inhibiting DNA-gyrase in susceptible organisms.
Clinical Context: Tetracycline treats susceptible bacterial infections of gram-positive and gram-negative organisms as well as infections caused by Mycoplasma, Chlamydia, and Rickettsia species. It inhibits bacterial protein synthesis by binding with 30S and possibly 50S ribosomal subunit(s) of susceptible bacteria.
Clinical Context: Doxycycline inhibits protein synthesis and, thus, bacterial growth by binding with 30S and, possibly, 50S ribosomal subunits of susceptible bacteria.
Clinical Context: Ceftazidime is a third-generation cephalosporin that has broad gram-negative spectrum, lower efficacy against gram-positive organisms, and higher efficacy against resistant organisms. It arrests bacterial cell wall synthesis and inhibits bacterial growth by binding to one or more of the penicillin-binding proteins.
Antibiotics are indicated for outpatient treatment of early or minor wound infections and prophylaxis for high-risk wounds (deep puncture wounds, grossly contaminated wounds, persons who are chronically ill or immunocompromised).
Trimethoprim/sulfamethoxazole, ciprofloxacin, tetracycline, and doxycycline are referenced as the initial oral antibiotics of choice in different sources for uncomplicated wound infection or prophylaxis following marine-acquired injuries. Other antibiotics mentioned include cephalexin, amoxicillin, and amoxicillin clavulanate.
Broad-spectrum parenteral antibiotics are indicated for serious wound infections (eg, cellulitis, myositis, gas gangrene) or sepsis following injuries sustained in the marine environment. The mortality rate for a Vibrio species wound infection approaches 50% (usually patients with chronic liver disease), and serious Aeromonas species infection may mimic clostridial gas gangrene.
No controlled studies exist regarding efficacy of therapy. Several references suggest both a tetracycline and either an extended-spectrum cephalosporin or aminoglycoside.
Clinical Context: Prednisone is useful in the treatment of inflammatory and allergic reactions. By reversing increased capillary permeability and suppressing PMN activity, it may decrease inflammation.
Clinical Context: Triamcinolone treats inflammatory dermatosis that is responsive to steroids. It decreases inflammation by suppressing the migration of PMNs and reversing capillary permeability.
Clinical Context: Hydrocortisone has mineralocorticoid activity and glucocorticoid effects. It decreases inflammation by suppression of the migration of PMNs and reversal of increased capillary permeability. It is useful in the management of inflammation caused by immune responses.
Corticosteroids may be indicated for treatment of delayed tissue reactions. These occur in the form of either nodular or diffuse granulomatous lesions, occurring up to 3 months after penetrating echinoderm injuries, particularly those from sea urchins. Generally, though not exclusively, these result from unrecognized retained spine fragments. Intralesional and/or systemic corticosteroid therapy may be beneficial, although clearly less efficacious than surgical removal of spine fragments. Topical corticosteroids may be useful for treatment of dermatitis.
Clinical Context: Tetanus immune globulin is used for passive immunization of any person with a wound that may be contaminated with tetanus spores.
Clinical Context: Diphtheria-tetanus toxoid is used to induce active immunity against tetanus in selected patients. It is the immunizing agent of choice for most adults and children older than 7 years. It is necessary to administer booster doses to maintain tetanus immunity throughout life.
Pregnant patients should receive only tetanus toxoid, not a diphtheria antigen-containing product.
In children and adults, it may be administered into the deltoid or midlateral thigh muscles. In infants, the preferred site of administration is midlateral thigh.
Generally, immunization against tetanus is considered for this type of envenomation. A booster injection in previously immunized individuals is recommended to prevent this potentially lethal syndrome. Patients who may not have been immunized against Clostridium tetani products should receive tetanus immune globulin (Hyper-Tet).
Echinoderm envenomations. Close-up of brittle star arm. Although spiny, members belonging to this class (Ophiuroidea) generally are considered harmless. Of the phylum Echinodermata, only starfish (class Asteroidea), sea urchins (class Echinoidea), and sea cucumbers (class Holothuroidea) are capable of envenomation. Photo courtesy of Scott A. Gallagher, MD.
Echinoderm envenomations. Close-up of brittle star arm. Although spiny, members belonging to this class (Ophiuroidea) generally are considered harmless. Of the phylum Echinodermata, only starfish (class Asteroidea), sea urchins (class Echinoidea), and sea cucumbers (class Holothuroidea) are capable of envenomation. Photo courtesy of Scott A. Gallagher, MD.