Jellyfish are found in every ocean and are prevalent in the tropics and northern Europe [1] [2] [3] [4] [5]. Of nearly 9000 species, only around 100 cause harm to humans [1] [2]. Specifically, Physalia physalis [5], Chironex fleckeri [6], and Carukia barnesi are the three most toxic species. Jellyfish sting is a frequent event as it has been reported that 150 million incidents occur annually [7]. There are as many as 800 incidents in some Pacific locations daily [8]. Fortunately, most jellyfish stings result in recovery.

Depending on the type of species and the envenomation dose [9], effects can range from mild symptoms to rapid fatality [10] [11] [12]. Local symptoms and signs include pain, swelling, pruritus, and eventually necrosis at the site of an injection [1] [10] [13]. Purplish-brownish vesicles develop and may last anywhere from minutes to weeks.

Systemic findings, if present, include nausea, emesis, fever, malaise, headache, paresthesias, and muscular spasms [14] [15]. Multiorgan effects reflect the involvement of gastrointestinal, cardiovascular, hematologic, neurologic, urinary, musculoskeletal, immunologic, and/or pulmonary systems [10] [16]. Additionally, ophthalmologic manifestations can include conditions such as ulceration of the cornea, conjunctivitis, and swelling of the eyelids.

While the majority of cases are nontoxic, some lead to sequelae such as infection of the wound, acute kidney failure, hemolysis, rhabdomyolysis, pulmonary edema and respiratory distress, dangerous arrhythmias, and cardiopulmonary arrest [14] [15] [16] [17].

Chronic effects include dermatologic features such as the development of keloids and granulomas and changes in pigmentation.

Vital signs changes may include tachycardia and alteration in blood pressure [14] [15]. Furthermore, the sting site is characterized by tenderness, erythema, and edema [6]. The color change and scarring may be permanent [16].

• Animal Bite

  Animal bites and stings may not figure highly in the differential diagnosis of facial swelling in the United Kingdom but should be considered in those who have been in a tropical area. [ncbi.nlm.nih.gov]

  Read more about treating animal bites . [uamshealth.com]

  Trusted Links MedlinePlus: Animal Bites [skinsight.com]

• Gangrene

  Despite serial monitoring with prompt fasciotomy and repeated debridement, he developed progressive ischaemia in multiple digits with gangrenous change. He subsequently underwent major reconstructive surgery and aggressive rehabilitation. [ncbi.nlm.nih.gov]

• Asymptomatic

  After 5 asymptomatic weeks, she developed unilateral orbital inflammation that did not respond to systemic antibiotics, antihistamines, or steroids. Imaging revealed a rapidly growing mass of the right lacrimal gland. [ncbi.nlm.nih.gov]

• Dyspnea

  In some cases, depending on the sensitivity of the person and the species of jellyfish, severe localized pain and nausea, weakness, excessive lacrimation, nasal discharge, muscle spasm, perspiration, difficulty in swallowing, and dyspnea may occur. [medical-dictionary.thefreedictionary.com]

• Vomiting

  Nausea or Vomiting Patients stung by a jellyfish can experience stomach upset side effects within minutes of injury. These stomach-related side effects can include nausea or vomiting, which may occur in conjunction with diarrhea. [livestrong.com]

  Seek medical care if the person is having difficulty breathing, is bleeding profusely, or other body-wide (generalized) symptoms are occurring, such as the following: Nausea or vomiting Paralysis Sweating Weakness Cramps Diarrhea There is pain in an [skinsight.com]

  Large venom symptoms are vomiting, dizziness, weakness and headache. Anaphylaxis (A severe allergic reaction). Life-threatening reactions are very rare with the stings. Most are caused by box jellyfish found in the South Pacific and Australia. [kidsclinic.pediatricweb.com]

  “A person stung by a jellyfish may suffer from nausea or vomiting and have difficulty breathing along with pain in unaffected areas, such as the groin or armpit.” [uamshealth.com]

• Nausea

  Nausea or Vomiting Patients stung by a jellyfish can experience stomach upset side effects within minutes of injury. These stomach-related side effects can include nausea or vomiting, which may occur in conjunction with diarrhea. [livestrong.com]

  In some cases, depending on the sensitivity of the person and the species of jellyfish, severe localized pain and nausea, weakness, excessive lacrimation, nasal discharge, muscle spasm, perspiration, difficulty in swallowing, and dyspnea may occur. [medical-dictionary.thefreedictionary.com]

  Seek medical care if the person is having difficulty breathing, is bleeding profusely, or other body-wide (generalized) symptoms are occurring, such as the following: Nausea or vomiting Paralysis Sweating Weakness Cramps Diarrhea There is pain in an [skinsight.com]

  Systemic findings, if present, include nausea, emesis, fever, malaise, headache, paresthesias, and muscular spasms. [symptoma.com]

• Diarrhea

  Seek medical care if the person is having difficulty breathing, is bleeding profusely, or other body-wide (generalized) symptoms are occurring, such as the following: Nausea or vomiting Paralysis Sweating Weakness Cramps Diarrhea There is pain in an [skinsight.com]

  These stomach-related side effects can include nausea or vomiting, which may occur in conjunction with diarrhea. Certain patients can also develop a fever or begin to sweat profusely. [livestrong.com]

  Coughing, wheezing, difficulty breathing, or a feeling of fullness in the mouth, throat, or neck Light-headedness, confusion, or agitation Headache, dizziness, or vertigo Nausea, vomiting, diarrhea, and stomach cramps Fever and chills Hives and flushing [healthlinkbc.ca]

  The progressive effects of a jellyfish sting may include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness/tingling, and muscle spasms. Severe reactions can cause difficulty breathing, coma, and death. [emedicinehealth.com]

• Abdominal Pain

  Seek medical attention right away for any breathing difficulties, chest or abdominal pains, or profuse sweating. Otten EJ. Venomous animal injuries. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. [medlineplus.gov]

  When to see your doctor Call your doctor if you have been stung and have: increasing numbness or difficulty breathing signs of poisoning: abdominal pain, muscle cramps, nausea, vomiting signs of infection later: increasing pain, redness, swelling, red [health.govt.nz]

  The progressive effects of a jellyfish sting may include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness/tingling, and muscle spasms. Severe reactions can cause difficulty breathing, coma, and death. [emedicinehealth.com]

• Chest Pain

  Certain patients may also experience chest pain in conjunction with these side effects. These patients require immediate emergency medical care to prevent further medical complications. [livestrong.com]

  Get medical attention right away if pain increases or there are any signs of breathing difficulty or chest pains. As soon as possible, rinse the sting site with large amounts of household vinegar for at least 30 seconds. [medlineplus.gov]

  pain fits or seizures severe swelling around the affected area severe bleeding vomiting lightheadedness or loss of consciousness Find your nearest A&E department Symptoms of sea creature stings The main symptoms of sea creature stings are intense pain [nhs.uk]

• Cyanosis

  We report a case of digital ischaemia in a 31-year-old man who presented with sudden hand numbness, swelling, and cyanosis 4 days after a jellyfish sting. [ncbi.nlm.nih.gov]

• Muscle Cramp

  Muscle Cramps A jellyfish sting can cause side effects of muscle cramping in affected patients, according to Medline Plus, a medical information website supported by the National Institutes of Health. [livestrong.com]

  […] spasms Numbness and weakness Pain in the arms or legs Raised red spot where stung Runny nose and watery eyes Swallowing difficulty Sweating SEA NETTLE Mild skin rash (with mild stings) Muscle cramps and breathing difficulty (from a lot of contact) SEA [medlineplus.gov]

  Muscle spasm, muscle cramps, joint pain, or generalized aching Credits By Healthwise Staff Primary Medical Reviewer William H. [healthlinkbc.ca]

• Thigh Pain

  Ten days later, she developed low back and right thigh pain followed by progressive numbness and weakness in all extremities. These symptoms reached their peak in 30 days and slowly began to improve. [ncbi.nlm.nih.gov]

• Joint Stiffness

  You may have a fever, weakness, or joint stiffness or swelling. Medical treatment may ease the discomfort and prevent complications from a delayed reaction. [healthlinkbc.ca]

• Lacrimation

  Imaging revealed a rapidly growing mass of the right lacrimal gland. Urgent anterior orbitotomy was performed and the lacrimal gland was biopsied. [ncbi.nlm.nih.gov]

  In some cases, depending on the sensitivity of the person and the species of jellyfish, severe localized pain and nausea, weakness, excessive lacrimation, nasal discharge, muscle spasm, perspiration, difficulty in swallowing, and dyspnea may occur. [medical-dictionary.thefreedictionary.com]

• Foreign Body Sensation

  Following debridement of the traumatized areas, the corneal epithelium healed completely in 24 hours, resulting in increased visual acuity and decreased foreign body sensation. [ncbi.nlm.nih.gov]

• Eczema

  Considering eczema, topical steroid treatment and occlusive dressing technique were started but the nodule remained. [ncbi.nlm.nih.gov]

  Hydrocortisone eczema cream. • if muscle spasms persist see a doctor. [bugbog.com]

  […] as benzocaine cleanse ulcerated wounds several times a day and keep covered with antibiotic ointment Other treatments systemic antibiotics for wound infections tetanus booster if status unknown or lapsed corticosteroids and antihistamines for delayed eczema-type [drhull.com]

• Papule

  At his first visit, he had a hard linear nodule on his left lower leg, and papules with excoriation were scattered over the lower limbs. [ncbi.nlm.nih.gov]

• Facial Swelling

  The report emphasizes the requirement to consider unusual aetiological factors in cases of facial swelling. [ncbi.nlm.nih.gov]

• Headache

  Systemic findings, if present, include nausea, emesis, fever, malaise, headache, paresthesias, and muscular spasms. [symptoma.com]

  With severe stings — when a lot of venom is injected into the skin or when a person is extremely allergic to the venom — weakness, dizziness, nausea, headache, muscle aches, spasms and difficulty breathing can result. [chop.edu]

  Nausea and vomiting Muscle and joint pain Fever Loss of consciousness Difficulty breathing Headache Weakness and dizziness Heart problems FastMed Is There When You Need Us Even if you use a home remedy to help relieve itching and burning of your child [fastmed.com]

  Symptoms (as little as 5 minutes after apparently mild stings) • lower back pain, intense headache. • muscle cramps and shooting pains, nausea, vomiting. • catastrophically high blood pressure. • restlessness and feeling of impending doom. • death from [bugbog.com]

  Symptoms of stings from different types of jellyfish are: LION'S MANE Breathing difficulty Muscle cramps Skin burning and blistering (severe) PORTUGUESE MAN-OF-WAR Abdominal pain Changes in pulse Chest pain Chills Collapse Headache Muscle pain and muscle [medlineplus.gov]

• Seizure

  […] ibuprofen do not use vinegar do not pee on the sting do not apply ice or a cold pack do not touch any spines with your bare hands do not cover or close the wound Go to A&E or call 999 if you have been stung and have: difficulty breathing chest pain fits or seizures [nhs.uk]

• Mononeuropathy

  Jellyfish sting may cause focal mononeuropathies most probably because of the local effects of the toxins. [ncbi.nlm.nih.gov]

• Areflexia

  Initial neurologic examination showed areflexia, weakness, absent vibration and position sense, and hyperesthesia to pin and light touch in the mid to distal region of all four extremities. [ncbi.nlm.nih.gov]

• Guillain-Barré Syndrome

  This is the case of a jellyfish sting associated with the rare development of Guillain-Barré syndrome. The patient, a 66-year-old woman, was stung by a jellyfish on the right thigh while swimming in the Atlantic Ocean, off Charleston, SC. [ncbi.nlm.nih.gov]

A detailed history should be elicited from the patients and/or witnesses if possible. The key questions should consist of details about the time of the sting, the onset and evolvement of the clinical features, the location of the incident, and identity of the organism. Very importantly, a physical exam must be performed and the patient should be immediately evaluated for the basic life support as well as for the evidence of local and systemic effects [10]. Additionally, the clinician should eliminate the tentacles as much as possible [1] [18]. Note that patients with anaphylaxis should be managed urgently and resuscitated promptly. Pain and wound care are also important to treat.

Individuals with severe manifestations should be assessed for organ damage with a complete blood count (CBC), complete metabolic panel (CMP) including renal and liver function tests, cardiac enzymes, thyroid function tests, and creatine phosphokinase. Additionally, urinalysis and arterial blood gases (ABG) should be performed.

Chest radiography is indicated for patients with respiratory distress.

Electrocardiogram (ECG) is useful for identifying arrhythmias. Finally, skin samples can be evaluated for the presence of nematocysts.

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