Butterfly, Moth, and Caterpillar Envenomation (2024)

Continuing Education Activity

Of the nearly 165,000Lepidopteraspecies found worldwide, only about 150 species causesignificant envenomations, with about 50 species found in the United States.Lepidopterais the order of insects thatincludes butterflies, moths, and caterpillars. Several caterpillars (the larvalformof butterflies and moths) containspines or urticating hairs that secrete a toxin, causing skin manifestations such as localized pain, edema, and erythema. Somecaterpillar species can cause severe injuries, including allergic reactions, consumptive coagulopathy, intracranial hemorrhage, acute kidney injury, ataxia, dysarthria, arthritis, joint deformities, wheezing, and dyspnea. The puss moth caterpillar (Megalopyge opercularis) is considered one of the most toxic in North America and is responsible for hundreds of human envenomations annually.Lonomia obliquacaterpillars found in South America, especially in Brazil, are infamous for causing severe pain and hemorrhagic syndrome. Contrastingly, theAnaphe venatacaterpillar in Nigeria is an essential protein resource from a cultural-specific dietand can cause thiamine deficiency syndrome similar to dry beriberi.

This CME course is designed to empower healthcare professionals with a profound understanding of Lepidoptera envenomations, a niche yet critical aspect of vector-borne emergencies. Despite the vast diversity of Lepidoptera species globally, only a fraction poses a significant threat to human health. This course aims to bridge the gap surrounding these envenomations' clinical manifestations, etiology, and management, ensuring clinicians cannavigate these unique challenges. Through participation in this activity,learners will be adept at identifying Lepidoptera envenomations, differentiating between toxic species, and implementing evidence-based management strategies. The interprofessional approach ensures that clinicians, nurses, and other healthcare professionals collaborate seamlessly, ultimately improving patient outcomes and reducing the long-term impact of these unique vector-borne emergencies.

Objectives:

• Identify the signs and symptoms of Lepidopteraenvenomations.

• Implement the appropriate management ofLepidopteraenvenomations.

• Differentiate the pathophysiology of envenomations in eachLepidopteraspecies.

• Collaborate with all members of the interprofessional team, including the medical toxicologist a the regional poison control center, to provide efficient, comprehensive, and coordinated care.

Access free multiple choice questions on this topic.

Introduction

Lepidopterais an order of insects that includes butterflies, moths, and caterpillars. Several caterpillars (the larval form of butterflies and moths)found worldwide containspines or urticating hairs that secrete a toxin, irritating humans upon contact.[1]Skin manifestations such as localized pain, edema, and erythema comprise most clinical presentations ofLepidopteraenvenomation.[2][3]However, some caterpillar species can cause severe injuries, including allergic reactions, consumptive coagulopathy, intracranial hemorrhage (ICH), acute kidney injury (AKI), ataxia, dysarthria, arthritis, joint deformities, wheezing, and dyspnea.[4][3][5]

"Lepidopterism" (derived from the Greek wordslepis,meaning scale, andpteron,meaning wing) refers to the various skin and systemic reactions secondary to human contact with moths and butterflies.[5]"Erucism" (derived from the Latin worderuca, meaning caterpillar) refers to cutaneous dermatitis resulting from contact with caterpillars with urticating hairs.[5][6]

More than 50 species of caterpillars are venomous in the US. The puss moth caterpillar (Megalopyge opercularis) is considered one of the most toxic in North America and causes hundreds of human envenomations annually.[7][8]Other common names include asp, tree asp, Italian asp, wooly asp, opossum bug, wooly slug, and "el perrito."[7]The puss caterpillar is found in the southeast and south-central US (particularly Texas, Louisiana, and Florida) and is abundant during the late spring (June-July) through the early fall season (September-October).[9][10]The species is often found in trees and shrubbery around homes, schools, and parks.[7]The typical physical characteristics include a teardrop-shaped furry body with silky tan to brownish hairs.[9]Beneath this furry coat are short hollow spines attached to a venom sac that discharges upon contact.[3][11]The color of the spines ranges from white, grey, tan, or yellow to reddish-brown.[12][1]

Other notable venomous caterpillars in the US include the flannel moth (Megalopyge crispata), the lo moth (Automeris io), the saddleback moth (Acharia stimulata), and the hickory tiger moth (Lophocampa caryae).[2][13]Lonomia obliquacaterpillars in South America, especially in Brazil, are infamous for causing severe pain and hemorrhagic syndrome.[14][15]In Australia, caterpillars such as the mistletoe brown-tail moth (Euproctis edwardsi), processionary caterpillars (Ochrogaster lunifer), cup moths (Doratifera spp.), and the white-stemmed gum moth (Chelepteryx collesi) are of medical importance.[16]Pine processionary caterpillars (Thaumetopoea pityocampa) are the important defoliator of pine forests in the Mediterranean and central European countries, with significant economic and occupational consequences for workers in these forests.[17]TheAnaphe venatacaterpillar in Nigeria is an essential protein resource but can cause thiamine deficiency syndrome similar to dry beriberi.[18][19]Additionally, dendrolimus caterpillars in China andPreolis semirufacaterpillars in Brazil are linked to significant joint disease.[20][4]

Etiology

Caterpillars, rather than adult butterflies and moths, cause most cases of lepidopterism and erucism.[3][21]Envenomation occurs by physical contact with a caterpillar'ssetae,hairlike hollow structures connected to a single basal poison gland or secretory epithelial cells. Venom accumulates and is stored in the setae and may fracture and release venom upon physical contact.[12]Setae may be embedded into the skin or mucous membranes, resulting in an irritant reaction distinct from a venomous reaction.[22]Certain species of moths also contain setae or spines.[5]However, most adult species lose their irritating setae when they emerge from their cocoons and become relatively harmless. Some caterpillar species do not produce venom.

Eye exposure of either hemolymph and setae results in acute scleritis or ophthalmia nodosa; this manifests as simple conjunctivitis and progresses into a more severe panophthalmitis when setae penetrate the cornea.[23]In rare cases, cataracts may develop.[24]Reactions are mostly from the toxic effects of the setae/hemolymph or immunoglobulin E (IgE) production that results in a hypersensitive state and manifests as a type IV (T-cell-mediated) hypersensitivity reaction, usually from direct contact.[25]Other vectors include airborne transmission spread by wind or carried on pets and other natural objects.[26]

Epidemiology

AlthoughLepidopteraare worldwide, only a few species cause harmful human reactions. In 2021, the Annual Report of the National Poison Data Systems from America's Poison Control reported 1014 caterpillar exposure cases.[27]Most exposures were accidental, with 47% of cases occurring in adults 20 years or older and 35% in children 12 years or younger.[27]Being naturally curious, children are at a somewhat increased risk of exposure.[22]Cases are more numerous among men than women. There were no reported deaths due to caterpillar exposures.[27]However, the actual number of cases and adverse reactions are likely underestimated due to underreporting, as most exposures are mild and self-limiting.

Exposures to caterpillar stings are usually unintentional and vary depending on the region and season.[26]Occupations requiring climbing trees or working closely with plants are risk factors in adults. In Brazil, thePremolis semirufacaterpillar (natively called pararama) is of significant concern as an occupational disease for rubber tappers (harvesters of latex from rubber trees).[2]Setae disperses through the air, particularly in regions where indigenous species molt—leading to multiple exposures, especially during seasons of abundance.[28]

Spring or summer can result in a spike in cases about school recess, camping/hiking, logging activity, or landscaping.[26][9]Ophthalmia nodosa is a seasonal disease due to the preponderance of caterpillars during the autumn months (August-October). However, the exact incidence of the disease is unknown.[29]

Pathophysiology

Caterpillars and their toxins have not been thoroughly investigated, except the Premolis semirufa of Brazil, South American Lonomia, andThaumetopoea pityocampa.

Dendrolimiasisdescribes urticarial dermatitis and joint symptoms resulting from exposure to theDendrolimusspeciescaterpillar of China andPreolis semirufacaterpillars of Brazil.[28]ThePremolis semirufacaterpillar is of significant concern as an occupational disease for rubber tappers (harvesters of latex from rubber trees) in Brazil. The venom contains formaldehyde and uncharacterized histamine analogs with a tropism for receptors in the bones, joints, and cartilage. During the acute phase of envenomation, there is a strong inflammatory response that is IgE-mediated.[30]Frequent unintentional exposures lead to chronic symptoms, featuring synovial membrane thickening, joint deformities, and chronic mono or oligoarticular synovitis. This chronic bone and joint disease is believed to be autoimmune-mediated and is calledpararamose.[30]

The hickory tussock moth (Lophocampa caryae) located in North America produces a histamine reaction upon human contact. The toxin's exact mechanism and chemical composition are not fully elucidated.[31]Similarly, the pine processionary caterpillar (Thaumetopoea pityocampa) possesses a toxin called thaumetopoein that also causes a histamine reaction.[32][33]

Ophthalmia nodosais a rare but well-documented ocular disease caused by a reaction to embedded urticarial hairs of several arthropods, including caterpillars, moths, and tarantulas.[34]This disease initially produces conjunctivitis with subsequent panuveitis due to corneal penetration and intraocular migration of urticating hairs or setae.[35][36][37][38][39]The conjunctiva and iris subsequently form granulomatous nodules in response to the caterpillar hairs or setae. The clinical effects depend on the initial injury force, the effect of the urticating toxin, and the intraocular locomotion of the hair or setae. Constant iris movement, respirations, and pulsations are thought to propel the hairs or setae. Listed below is a practical classification scheme for the disease created by Caderaet al.[40]

Classification of Ophthalmia Nodosa (Cadera et al)

Type 1:An immediate response to the hair involving chemosis and inflammation for several weeks.

Type 2:The presence of hairs embedded in the bulbar or palpebral conjunctiva causing chronic mechanical keratoconjunctivitis, resulting in a foreign body sensation and linear corneal abrasions.

Type 3:Grey-yellow granulomatous nodules may form in the conjunctiva due to subconjunctival or intracorneal setae. These nodules may be asymptomatic.

Type 4:Hair penetration of the anterior eye segment may lead to iritis as a secondary complication.

Type 5:Involvement of the vitreoretinal region may occur when hairs penetrate the posterior segment via the anterior chamber or transscleral, which may take several years to manifest. The effects can vary from mild vitritis with or without cystoid macular edema to severe endophthalmitis.[34][40][36]

Lonomismis a severe hemorrhagic disease caused by envenomation of theLonomiaspecies.[2]The disease is characterized by a syndrome of consumptive coagulopathy and fibrinolysis secondary to the venom, the proteolytic enzyme lonomin V found in the hairs, spines, and hemolymph of theLonomiaspecies caterpillars (Lonomia obliqua,Lonomia achelous). Lonomin V activates factor X, factor II (prothrombin), and collagen degradation, leading to platelet inhibition.[2]Suggested mechanisms of toxin-mediated AKI are dilation of Bowman capsule and increased permeability of the tuft capillaries, resulting in the deposition of fibrinolytic compounds and initiating the conditions for acute tubular necrosis (ATN).[41]Systemic lonomism manifests as a consultive coagulopathy with secondary fibrinolysis, although most deaths result from acute kidney injury.[42]

The venoms of bothLonomiaspecies provoke similar clinical effects with different mechanisms of action.[43]TheL obliquavenom is mediated mainly by thrombin formation secondary to procoagulant toxins at different levels of the coagulation cascade, as opposed to theL achelousvenom, which activates both fibrinolysis and clotting pathways resulting in mild disseminated intravascular coagulation (DIC).[44]Factor XIII is drastically reduced inL achelousenvenomated patients due to a factor XIII degradation component in the venom. However, theL obliquavenom contains a factor X activator called Losac (Lonomia obliquaStuart factor activator)and a prothrombin activator called Lopap(Lonomia obliqua prothrombinactivator protease).[45][46]Results from studies have suggested that a combination of DIC due to thrombin formation, intravascular fibrin formation, and secondary activation of the fibrinolytic syndrome are responsible forL obliquahemorrhagic syndrome.[47]The difference in hemorrhagic syndrome prodrome between the 2 species plays a vital role in the treatment.[48][44]

Seasonal ataxiais a clinical syndrome of acute cerebellar ataxia, nausea, and vomiting. This condition has been implicated in epidemics in western Nigeria during the 1950s, caused by consuming the African silkworm (Anapha venata) for protein.[49][18][50][51]Coinciding with the rainy season (July-October), the larvae are abundantly found in local markets and frequently consumed with high carbohydrate-based foods, which contain thiamine-binding cyanogenetic glycosides.[51]However, the larvae of theAnapha venatacontain heat-resistant thiaminases that exacerbate the thiamine-deficient population.[49]

Histopathology

Controlled studies involving injecting venom fromLonomia speciesinto laboratory rats demonstrate histopathologicchanges consistent with ATN. Specifically, increased acidophilia, dilation of renal tubules, loss of proximal brush border, cytoplasm vacuolation, nuclear pyknosis, and desquamation of necrotic cells.[41]Continuing research is underway for other caterpillar species and their venom.

Toxico*kinetics

Toxicologic studies of caterpillar venom aremost prevalent in the toxicologyand dermatology literature; however, more studies are necessary for a complete understanding. Current research has found that Lepidopteravenom contains peptides, hyaluronidase, phospholipase A, and bioamines such as histamine (or histamine-releasing substances).[2]

History and Physical

Caterpillar exposures can be categorized into 2 types: stinging reactions and pruritic reactions, although there may be some overlap.[28]Stinging caterpillars possess hollow spines that release venom upon contact. The stinging reaction is characterized by a painful burning sensation with local and rarely systemic effects. The affected area becomes swollen and erythematous and may develop papules and vesicles. A gridlike pattern rash may develop within 2 to 3 hours of exposure. Certain species leave pathognomonic skin patterns, such as an "M" shape seen with opercularis stings, often with a gridlike pattern matching the caterpillar's spine distribution.[2]Associated systemic symptoms may also include nausea, vomiting, fever, headache, restlessness, tachycardia, hypotension, urticaria, seizures, lymphadenitis, and local adenopathy.

On the other hand, exposure to itchy caterpillars with non-venomous urticating hairs can lead to pruritic reactions. These reactions can result from mechanical irritation, an allergic reaction, or a granulomatous reaction due to the chronic presence of the hairs.[4]TheOchrogaster luniferof Australia is known to cause intense pruritic dermatitis. Allergic reactions, dermatitis, and anaphylaxis are associated with theThaumetopoea pityocampaof Asia, North Africa, and Europe.

Dendrolimiasis is a chronic form of lepidopterism caused by direct contact with the central Asian pine tree lappet caterpillar (Dendrolimus sp)found in China. The clinical effects of this condition include maculopapular dermatitis, inflammatory migratory polyarthritis and polychondritis, chronic osteoarthritis, and rarely acute scleritis. Associated symptoms include fever, anorexia, fatigue, chills, headaches, and dizziness.[52]

Pararamose is a similar disease to dendrolimiasis and is associated with direct contact with thePremolis semirufacaterpillar of Brazil.[2]This is a significant occupational hazard for rubber tree plantation workers in the Brazilian Amazon rainforest. The clinical effects are similar to dendrolimiasis and include painful/pruritic dermatitis associated with painful arthritis and joint deformities after repeated exposures to the caterpillar.

A hemorrhagic syndrome characterized by a consumptive coagulopathy and secondary fibrinolysis is associated with the South AmericanLonomia spcaterpillars in Brazil, Venezuela, and northern Argentina.[2]Of the 26Lonomiaspecies, only 2 are known to cause a severe coagulation disorder: theLonomia obliqua,located in Southern Brazil, and theLonomia achelous,located in Venezuela and Northern Brazil.[53]Both species result in a consumptive coagulopathy similar to disseminated intravascular coagulation (DIC). High fatality rates occur from pulmonary and intracerebral hemorrhage with acute renal failure due to the venom's nephrotoxicity and microcirculatory fibrin deposition.[43]The first symptoms after contact include intense burning, erythema, edema, heat, and blistering. Consumptive coagulopathy can occur at 6 to 72 hours after envenomation; however, this may occur within 4 to 6 hours after contact withL obliqua.[54]

Evaluation

Laboratory or imaging studies are notrequired for most caterpillar envenomations limited to the skin.

The followingstudies should be considered forLepidopteraenvenomations according to the corresponding species syndrome:

• Complete blood count

• Coagulation studies (prothrombintime,activated partial thromboplastin time, fibrinogen level, fibrin degradationproducts, and D-dimer)

• Basic metabolic panel (specifically BUN and creatinine)

• Urinalysis to evaluate for blood and protein

• Chestradiography if significant respiratory symptoms are present

• Electrocardiogramfor tachycardiaor dysrhythmias

• Slit-lamp examination for ophthalmic exposures

• Fluorescencestain of the affected eye to rule out corneal abrasions

Treatment / Management

Supportive management for dermal Lepidoptera envenomation involves washing affected areas with soap and water and contactless drying using a hair dryer or fan. Careful application of adhesive tape at the bite site will assist in removing hairs.[7]Any constricting clothing or jewelry, such as rings, should be removed in anticipation of swelling of the affected extremity. Applying topical isopropyl alcohol and an ice pack accomplishes cooling measures. It is advisable to recommend tetanus prophylaxis.

Recommend urgent ophthalmologic consultation for any caterpillar-related eye exposures, typically for type 1 or 2 ophthalmia nodosa classifications. Ocular exposures should undergo irrigation with copious amounts of 0.9% sodium chloride solution. Administration of a topical ophthalmic anesthetic will significantly ease eye pain and facilitate examination and treatment. Examining the fornix of the eye for hairs with double eversion is essential. Slit-lamp examination of the affected eye includes fluorescein staining to determine the presence of corneal abrasions. Under a microscope, carefully remove caterpillar hairs using forceps or a 26-gauge hypodermic needle. After removal of the hairs, treatment includes topical steroids, cycloplegics, lubricants, and antibiotics.[55][56]

In type 3 lesions, surgical excision of granulomatous nodules by an ophthalmologist may be necessary. Type 4 lesions require topical steroids and may include iridectomy for the removal of nodules and hairs. Type 5 lesions may consist of both topical and systemic steroids, with resistant cases requiring vitrectomy for the removal of venomous hairs.[29]

Control pain control by administering topical anesthetics, minor analgesics, and opioids. Applying topical steroids will reduce conjunctival chemosis and lid edema and help with the eye examination. Manage cutaneous symptoms such as pruritus and urticaria with oral antihistamines. Treat respiratory symptoms with nebulized beta-agonists and systemic steroids. Anaphylaxis and severe respiratory symptoms may require intramuscular epinephrine and systemic steroids.The management of dendrolimiasis is primarily with supportive care. Recommend prompt surgery to remove sinus tracts and the affected cartilage to prevent permanent bone and joint deformities.Managing the hemorrhagic syndrome caused by exposure to theL obliquacaterpillar includes administering clotting factors, platelets, and cryoprecipitate.[46]The antidote for this syndrome is available in Brazil and is called antilonomic serum (SALon).[57][48]

Consulting a hematologist for suspectedLonomiaenvenomation is essential, as the managementL obliquaandL achelousare different.[46]Treatments such as cryoprecipitate, purified fibrinogen, and antifibrinolytics (aprotinin and ε-aminocaproic acid) have proven beneficial forL achelousenvenomations. In contrast, this transfusion regimen could potentially worsen the bleeding syndrome in cases ofL obliquaenvenomationand can be fatal. Recommend that patients envenomated by either species avoid receiving whole blood or fresh plasma transfusions, as these can exacerbate the hemorrhagic syndrome.[46]For those suffering from seasonal ataxia caused by the African silkworm (Anapha venata), supportive care and 100 mg of oral thiamine every 8 hours have been shown to reduce the symptoms within 2 days.[58]Consultation with a medical toxicologist or regional poison control center for any caterpillar envenomation for treatment guidance is also recommended.

Differential Diagnosis

The differential forLepidoptera envenomations include the following:

1. Dermatitis (Atopic, allergic, and contact)

2. Allergic reaction

3. Arthropodenvenomations (Insect bites, centipede, millipede, scorpion, tarantula, black widow spider, and brown recluse)

4. Corneal abrasions and ulcers from retained foreign bodies

5. Toxicodendronpoisoning

6. Henoch Schonlein purpura (HSP) or IgA Vasculitis

7. Idiopathic thrombocytopenic purpura(ITP)

8. Iritis and uveitis

Prognosis

The prognosisforLepidopteraenvenomation is excellent, except for complicated ocular exposures and persistent systemic symptoms. With appropriate ophthalmologic or other specialty care in a tertiary referral hospital, a full recovery is expected. There are rare reports of deaths due to caterpillar envenomation, but these are usuallythe result of inadequatemedical attention or exposurein austere locations.

Complications

The range of complications for caterpillar hair eye exposures depends on the penetration and effect of the urticating toxins. Brief exposures to the hairs may resultin conjunctival chemosis, corneal abrasions, lid edema, and a foreign body sensation that may last for weeks. Additional complicationsrange from chronic keratoconjunctivitis, corneal granulomas,chronic scleritis, iritis, and uveitis to cataract formation and impaired vision.[36]Systemic lonomism usually results in self-limited coagulopathy and renal impairment with the possibility of chronic renal insufficiency insome cases.

Consultations

Consultations for butterfly, moth, and caterpillar envenomations include the following:

• Medical toxicology or yourregional poison control center for any caterpillar envenomations

• Ophthalmology for urticating hair eye exposures

• Hematology for Lonomia envenomations

Deterrence and Patient Education

Educating the general public is essential for preventing caterpillar envenomations. Teaching children caterpillars should not be touched may prevent most unintentional exposures. Prudence dictates avoiding areas infested with caterpillars. A heightened level of awareness is essential during peak caterpillar seasons, such as spring/summer, especially in endemic areas. When outdoors, protective gear such as eye protection, long-sleeved shirts, long pants tucked into socks, work gloves, and a wide-brimmed hat may prevent envenomation upon unintentional contact with a caterpillar. Removing a caterpillar on the skin with a stick or tool rather than bare hands can prevent additional exposure to venom.

Pearls and Other Issues

Become familiar with the local/regional toxic caterpillars. Many websites aimed at the layperson are helpful, with descriptions and high-resolution photographs.

Enhancing Healthcare Team Outcomes

Prevention is the best approach to caterpillar envenomations. To prevent exposure, the healthcare team, including doctors, nurses, and pharmacists, should work toward teaching children and outdoor workers to identify these vectors. Everyone playing or working outdoors in endemic areas should have a heightened level of alertness during peak caterpillar seasons (spring/summer). Encourage patients to wear protective clothing. Clothing should include long-sleeved shirts, long pants tucked into socks, work gloves, and a wide-brimmed hat to minimize the likelihood of accidental exposure; further, using a tight-fitting respirator mask and eye protection can help ensure a secure work zone in known heavily infested areas.

Review Questions

• Access free multiple choice questions on this topic.

• Comment on this article.

References

1.

Diaz JH. The epidemiology, diagnosis, and management of caterpillar envenoming in the southern US. J La State Med Soc. 2005 May-Jun;157(3):153-7. [PubMed: 16173315]

2.

Hossler EW. Caterpillars and moths. Dermatol Ther. 2009 Jul-Aug;22(4):353-66. [PubMed: 19580579]

3.

Villas-Boas IM, Bonfá G, Tambourgi DV. Venomous caterpillars: From inoculation apparatus to venom composition and envenomation. Toxicon. 2018 Oct;153:39-52. [PubMed: 30145232]

4.

Seldeslachts A, Peigneur S, Tytgat J. Caterpillar Venom: A Health Hazard of the 21st Century. Biomedicines. 2020 May 30;8(6) [PMC free article: PMC7345192] [PubMed: 32486237]

5.

Hossler EW. Caterpillars and moths: Part I. Dermatologic manifestations of encounters with Lepidoptera. J Am Acad Dermatol. 2010 Jan;62(1):1-10. [PubMed: 20082886]

6.

Cabrera G, Lundberg U, Rodríguez-Ulloa A, Herrera M, Machado W, Portela M, Palomares S, Espinosa LA, Ramos Y, Durán R, Besada V, Vonasek E, González LJ. Protein content of the Hylesia metabus egg nest setae (Cramer [1775]) (Lepidoptera: Saturniidae) and its association with the parental investment for the reproductive success and lepidopterism. J Proteomics. 2017 Jan 06;150:183-200. [PubMed: 27568362]

7.

Eagleman DM. Envenomation by the asp caterpillar (Megalopyge opercularis). Clin Toxicol (Phila). 2008 Mar;46(3):201-5. [PubMed: 18344102]

8.

Pinson RT, Morgan JA. Envenomation by the puss caterpillar (Megalopyge opercularis). Ann Emerg Med. 1991 May;20(5):562-4. [PubMed: 2024798]

9.

Estrella M, Elston DM. What's eating you? Megalopyge opercularis. Cutis. 2020 Jul;106(1):23-24;27. [PubMed: 32915931]

10.

Severs GA, Elston DM. What's eating you? Megalopyge opercularis. Cutis. 2003 Jun;71(6):445-8. [PubMed: 12839254]

11.

Koehler AW, Zaveri KG. Lepidopterism caused by the puss caterpillar. J Am Assoc Nurse Pract. 2021 Mar 12;34(1):169-171. [PubMed: 33731556]

12.

Hossler EW. Caterpillars and moths: Part II. Dermatologic manifestations of encounters with Lepidoptera. J Am Acad Dermatol. 2010 Jan;62(1):13-28. [PubMed: 20082887]

13.

Lamdin JM, Howell DE, Kocan KM, Murphey DR, Arnold DC, Fenton AW, Odell GV, Ownby CL. The venomous hair structure, venom and life cycle of Lagoa crispata, a puss caterpillar of Oklahoma. Toxicon. 2000 Sep;38(9):1163-89. [PubMed: 10736472]

14.

Cardoso JL, Wen FH, França FO, Warrell DA, Theakston RD. Detection by enzyme immunoassay of Loxosceles gaucho venom in necrotic skin lesions caused by spider bites in Brazil. Trans R Soc Trop Med Hyg. 1990 Jul-Aug;84(4):608-9. [PubMed: 2091365]

15.

Da Silva WD, Campos CM, Gonçalves LR, Sousa-e-Silva MC, Higashi HG, Yamagushi IK, Kelen EM. Development of an antivenom against toxins of Lonomia obliqua caterpillars. Toxicon. 1996 Sep;34(9):1045-9. [PubMed: 8896196]

16.

Balit CR, Geary MJ, Russell RC, Isbister GK. Prospective study of definite caterpillar exposures. Toxicon. 2003 Nov;42(6):657-62. [PubMed: 14602121]

17.

Vega J, Vega JM, Moneo I, Armentia A, Caballero ML, Miranda A. Occupational immunologic contact urticaria from pine processionary caterpillar (Thaumetopoea pityocampa): experience in 30 cases. Contact Dermatitis. 2004 Feb;50(2):60-4. [PubMed: 15128315]

18.

Adamolekun B, Ibikunle FR. Investigation of an epidemic of seasonal ataxia in Ikare, western Nigeria. Acta Neurol Scand. 1994 Nov;90(5):309-11. [PubMed: 7887129]

19.

Adamolekun B, Ndububa DA. Epidemiology and clinical presentation of a seasonal ataxia in western Nigeria. J Neurol Sci. 1994 Jun;124(1):95-8. [PubMed: 7931428]

20.

Lawson JP, Liu YM. Pinemoth caterpillar disease. Skeletal Radiol. 1986;15(6):422-7. [PubMed: 3094159]

21.

Paniz-Mondolfi AE, Pérez-Alvarez AM, Lundberg U, Fornés L, Reyes-Jaimes O, Hernández-Pérez M, Hossler E. Cutaneous lepidopterism: dermatitis from contact with moths of Hylesia metabus (Cramer 1775) (Lepidoptera: Saturniidae), the causative agent of caripito itch. Int J Dermatol. 2011 May;50(5):535-41. [PubMed: 21506967]

22.

Branco MMP, Borrasca-Fernandes CF, Prado CC, Galvão TF, Silva MT, Mello De Capitani E, Hyslop S, Bucaretchi F. Management of severe pain after dermal contact with caterpillars (erucism): a prospective case series. Clin Toxicol (Phila). 2019 May;57(5):338-342. [PubMed: 30449184]

23.

Waikar S, Dhar SK. Ophthalmia nodosa with intraocular caterpillar setae. Med J Armed Forces India. 2011 Oct;67(4):400. [PMC free article: PMC4920657] [PubMed: 27365865]

24.

González-Martín-Moro J, Contreras-Martín I, Castro-Rebollo M, Fuentes-Vega I, Zarallo-Gallardo J. Focal cortical cataract due to caterpillar hair migration. Clin Exp Optom. 2019 Jan;102(1):89-90. [PubMed: 29961989]

25.

Morales-Cabeza C, Prieto-García A, Acero S, Bartolomé-Zavala B, Morgado JM, Matito A, Sánchez-Muñoz L, Alvarez-Twose I. Systemic mastocytosis presenting as occupational IgE-mediated anaphylaxis to pine processionary caterpillar. Ann Allergy Asthma Immunol. 2016 Sep;117(3):333-334.e1. [PubMed: 27474119]

26.

Ellis CR, Elston DM, Hossler EW, Cowper SE, Rapini RP. What's Eating You? Caterpillars. Cutis. 2021 Dec;108(6):346-351. [PubMed: 35167790]

27.

Gummin DD, Mowry JB, Beuhler MC, Spyker DA, Rivers LJ, Feldman R, Brown K, Nathaniel PTP, Bronstein AC, Weber JA. 2021 Annual Report of the National Poison Data System^© (NPDS) from America's Poison Centers: 39th Annual Report. Clin Toxicol (Phila). 2022 Dec;60(12):1381-1643. [PubMed: 36602072]

28.

Diaz JH. The evolving global epidemiology, syndromic classification, management, and prevention of caterpillar envenoming. Am J Trop Med Hyg. 2005 Mar;72(3):347-57. [PubMed: 15772333]

29.

Doshi PY, Usgaonkar U, Kamat P. A Hairy Affair: Ophthalmia nodosa Due to Caterpillar Hairs. Ocul Immunol Inflamm. 2018;26(1):136-141. [PubMed: 27438993]

30.

Gabrili JJM, Villas-Boas IM, Pidde G, Squaiella-Baptistão CC, Woodruff TM, Tambourgi DV. Complement System Inhibition Modulates the Inflammation Induced by the Venom of Premolis semirufa, an Amazon Rainforest Moth Caterpillar. Int J Mol Sci. 2022 Nov 01;23(21) [PMC free article: PMC9658021] [PubMed: 36362117]

31.

Pitetti RD, Kuspis D, Krenzelok EP. Caterpillars: an unusual source of ingestion. Pediatr Emerg Care. 1999 Feb;15(1):33-6. [PubMed: 10069310]

32.

Lamy M, Pastureaud MH, Novak F, Ducombs G, Vincendeau P, Maleville J, Texier L. Thaumetopoein: an urticating protein from the hairs and integument of the pine processionary caterpillar (Thaumetopoea pityocampa Schiff., Lepidoptera, Thaumetopoeidae). Toxicon. 1986;24(4):347-56. [PubMed: 3087028]

33.

Bonamonte D, Foti C, Vestita M, Angelini G. Skin Reactions to pine processionary caterpillar Thaumetopoea pityocampa Schiff. ScientificWorldJournal. 2013;2013:867431. [PMC free article: PMC3678440] [PubMed: 23781164]

34.

Fraser SG, Dowd TC, Bosanquet RC. Intraocular caterpillar hairs (setae): clinical course and management. Eye (Lond). 1994;8 ( Pt 5):596-8. [PubMed: 7835460]

35.

Sood P, Tuli R, Puri R, Sharma R. Seasonal epidemic of ocular caterpillar hair injuries in the Kangra District of India. Ophthalmic Epidemiol. 2004 Feb;11(1):3-8. [PubMed: 14977492]

36.

Sridhar MS, Ramakrishnan M. Ocular lesions caused by caterpillar hairs. Eye (Lond). 2004 May;18(5):540-3. [PubMed: 15131691]

37.

Fuentes Aparicio V, de Barrio Fernández M, Rubio Sotés M, Rodríguez Paredes A, Martínez Molero MI, Zapatero Remón L, Bartolomé Zavala B. Non-occupational allergy caused by the pine processionary caterpillar (Thaumetopoea pityocampa). Allergol Immunopathol (Madr). 2004 Mar-Apr;32(2):69-75. [PubMed: 15087093]

38.

Vissenberg I, Raus P, Van Tittelboom T, Dockx P, Tassignon MJ. Caterpillar induced kerato-conjunctivitis. Bull Soc Belge Ophtalmol. 1993;249:107-11. [PubMed: 7952337]

39.

Teske SA, Hirst LW, Gibson BH, O'Connor PA, Watts WH, Carey TM. Caterpillar-induced keratitis. Cornea. 1991 Jul;10(4):317-21. [PubMed: 1889218]

40.

Cadera W, Pachtman MA, Fountain JA, Ellis FD, Wilson FM. Ocular lesions caused by caterpillar hairs (ophthalmia nodosa). Can J Ophthalmol. 1984 Feb;19(1):40-4. [PubMed: 6608976]

41.

Berger M, Santi L, Beys-da-Silva WO, Oliveira FM, Caliari MV, Yates JR, Vieira MA, Guimarães JA. Mechanisms of acute kidney injury induced by experimental Lonomia obliqua envenomation. Arch Toxicol. 2015 Mar;89(3):459-83. [PMC free article: PMC4401067] [PubMed: 24798088]

42.

Favalesso MM, Cuervo PF, Casafús MG, Guimarães ATB, Peichoto ME. Lonomia envenomation in Brazil: an epidemiological overview for the period 2007-2018. Trans R Soc Trop Med Hyg. 2021 Jan 07;115(1):9-19. [PubMed: 32945864]

43.

Santos JHA, Oliveira SS, Alves EC, Mendonça-da-Silva I, Sachett JAG, Tavares A, Ferreira LC, Fan HW, Lacerda MVG, Monteiro WM. Severe Hemorrhagic Syndrome After Lonomia Caterpillar Envenomation in the Western Brazilian Amazon: How Many More Cases Are There? Wilderness Environ Med. 2017 Mar;28(1):46-50. [PubMed: 28087323]

44.

González C, Ballesteros-Mejia L, Díaz-Díaz J, Toro-Vargas DM, Amarillo-Suarez AR, Gey D, León C, Tovar E, Arias M, Rivera N, Buitrago LS, Pinto-Moraes RH, Sano Martins IS, Decaëns T, González MA, Kitching IJ, Rougerie R. Deadly and venomous Lonomia caterpillars are more than the two usual suspects. PLoS Negl Trop Dis. 2023 Feb;17(2):e0011063. [PMC free article: PMC9949635] [PubMed: 36821543]

45.

Alvarez Flores MP, Fritzen M, Reis CV, Chudzinski-Tavassi AM. Losac, a factor X activator from Lonomia obliqua bristle extract: its role in the pathophysiological mechanisms and cell survival. Biochem Biophys Res Commun. 2006 May 19;343(4):1216-23. [PubMed: 16597435]

46.

Arocha-Piñango CL, Guerrero B. Lonomia genus caterpillar envenomation: clinical and biological aspects. Haemostasis. 2001 May-Dec;31(3-6):288-93. [PubMed: 11910197]

47.

Alvarez AM, Alvarez-Flores MP, DeOcesano-Pereira C, Goldfeder MB, Chudzinski-Tavassi AM, Moreira V, Teixeira C. Losac and Lopap Recombinant Proteins from Lonomia obliqua Bristles Positively Modulate the Myoblast Proliferation Process. Front Mol Biosci. 2022;9:904737. [PMC free article: PMC9280836] [PubMed: 35847970]

48.

Sano-Martins IS, González C, Anjos IV, Díaz J, Gonçalves LRC. Effectiveness of Lonomia antivenom in recovery from the coagulopathy induced by Lonomia orientoandensis and Lonomia casanarensis caterpillars in rats. PLoS Negl Trop Dis. 2018 Aug;12(8):e0006721. [PMC free article: PMC6112677] [PubMed: 30114211]

49.

Ayoade Moyo A, Michael Bimbo F, Morenikeji Adeyoyin K, Valentine Nnaemeka A, Oluwatoyin G, Victor Oladeji A. Seasonal ataxia: A case report of a disappearing disease. Afr Health Sci. 2014 Sep;14(3):769-71. [PMC free article: PMC4209644] [PubMed: 25352901]

50.

Adamolekun B. Anaphe venata entomophagy and seasonal ataxic syndrome in southwest Nigeria. Lancet. 1993 Mar 06;341(8845):629. [PubMed: 8094850]

51.

Adamolekun B, McCandless DW, Butterworth RF. Epidemic of seasonal ataxia in Nigeria following ingestion of the African silkworm Anaphe venata: role of thiamine deficiency? Metab Brain Dis. 1997 Dec;12(4):251-8. [PubMed: 9475498]

52.

Huang DZ. Dendrolimiasis: an analysis of 58 cases. J Trop Med Hyg. 1991 Apr;94(2):79-87. [PubMed: 2023292]

53.

Burdmann EA, Antunes I, Saldanha LB, Abdulkader RC. Severe acute renal failure induced by the venom of Lonomia caterpillars. Clin Nephrol. 1996 Nov;46(5):337-9. [PubMed: 8953124]

54.

Valle Dos Anjos I, Gonzalez C, Diaz J, Sciani JM, Sano-Martins IS, Gonçalves LRC. Biological characterization of bristle extract of Lonomia descimoni caterpillar (Lepidoptera, Saturniidae) and effectiveness of Lonomia antivenom to neutralize experimental envenomation in rats. Toxicon. 2023 Feb;223:107004. [PubMed: 36566993]

55.

Yang JY, Shi XY. Vitreoretinal involvement of caterpillar hairs. Am J Ophthalmol. 2023 Oct;254:e1-e2. [PubMed: 37495005]

56.

Agarwal M, Acharya MC, Majumdar S, Paul L. Managing multiple caterpillar hair in the eye. Indian J Ophthalmol. 2017 Mar;65(3):248-250. [PMC free article: PMC5426133] [PubMed: 28440257]

57.

Medeiros DN, Torres HC, Troster EJ. Accident involving a 2-year-old child and Lonomia obliqua venom: clinical and coagulation abnormalities. Rev Bras Hematol Hemoter. 2014 Nov-Dec;36(6):445-7. [PMC free article: PMC4318469] [PubMed: 25453657]

58.

Adamolekun B, Adamolekun WE, Sonibare AD, Sofowora G. A double-blind, placebo-controlled study of the efficacy of thiamine hydrochloride in a seasonal ataxia in Nigerians. Neurology. 1994 Mar;44(3 Pt 1):549-51. [PubMed: 8145931]

Disclosure: Brad Goldman declares no relevant financial relationships with ineligible companies.

Disclosure: Vincent Lee declares no relevant financial relationships with ineligible companies.

Disclosure: Bradley Bragg declares no relevant financial relationships with ineligible companies.