Letter to Editor
Cutaneous Lepidopterism from the Caterpillar Apona sp.
Catherina Jessica Sutantoyo* and Johannes F. Dayrit
Corresponding Author: Catherina Jessica Sutantoyo, 9002 Research Drive, Filinvest Corporate City, Alabang, Muntinlupa city, Metro Manila, Philippines. Tel: +639175209520; E-mail: catherina.jessica@yahoo.com
Received: November 3, 2015; Revised: November 30, 2015; Accepted: November 26, 2015
Citation: Sutantoyo C, Dayrit J. (2015) Cutaneous Lepidopterism from the Caterpillar Apona sp.. Dermatol Clin Res, 1(3): 63-65.
Copyrights: ©2015 Sutantoyo C, Dayrit J. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Share :
  • 420

    Views & Citations


From July to September, there are increased chances of getting intimate with hairy caterpillars [1,2]. Their fine silky hair and seta (thin-gauged needlelike structure) may cause painful and/or itchy lesions. While erucism (caterpillar dermatitis) is characterized by a localized, pruritic, maculopapular contact dermatitis following exposure with toxic hair [3,4]. Lepidopterism on the other hand, is a rare systemic illness that occurs following such contact, typified by diffuse urticaria, which may or may not be, associated pulmonary symptoms [5]. Recent studies revealed increased serum IgE, cytokines and blood CD16/56+ NK precursor cells after exposure to caterpillars [6].

We report a case of a 35-year-old female who presented with intensely pruritic widespread urticarial papules and plaques after contact with a black hairy caterpillar. She was managed with a 2-week course of oral steroid, antihistamine and topical steroids with resolution of symptoms. She has a history of asthma and atopy. The caterpillar was identified at the RITM Department of Entomology, as larva of the moth Apona sp. She was treated with oral corticosteroid, antihistamine and Halobetasol propionate ointment for two weeks. Upon follow-up, resolutions of lesions were noted.

Caterpillars are worm-like larval forms of moths or butterflies (Order Lepidoptera, Class Insecta). They belong to phylum arthropoda with more than 165,000 species worldwide [7]. Most of them are harmless-looking and brightly-colored. However, 12 families of the caterpillar species can inflict serious human injuries from localized stings, papular dermatitis, urticarial wheals to consumption coagulopathy and renal failure [1]. Envenoming caterpillar utilizes urticating hair, setae or toxins for defense against predators. Lepidopterism (Greek lepıs: scale and pteron: wing) is defined as a spectrum of medical conditions due to contact with lepidoptera and/or their products. This includes cutaneous and/or mucosal manifestations that vary in severity from mild to severe reactions (anaphylactic shock and death) [5].

Erucism (Latin eruca: caterpillar) refers to localized cutaneous envenomation from poisonous caterpillar spines. These reactions are caused by caterpillars from three families: Saturniidae, Megalopygidae, and Limacodidae. Papular urticaria and dermatitis tend to be caused by furry caterpillars [8]. Caterpillar setae of some species are easily detached and can be dispersed by winds, causing dermatitis. This phenomenon has been documented with Thaumetopoea caterpillars [9,10]. Garments hung on clotheslines may collect airborne setae and cause dermatitis. In 1972, about 500,000 cases of dermatitis were caused by airborne setae from Asian mulberry tussock caterpillar [8].

Apona sp. larva belongs to the family Eupterotidae [11]. Eupterotidae is a member of the Moths of Southeastern Asia. There are 350 species of Eupterotidae worldwide; most common in Asia and New World tropics and it is commonly seen in Thailand and India [12-14]. Apona sp. are classically described as densely haired caterpillars. Its body is covered with long, black bristles with long strands (5 mm in length) at the posterior end. The head is black with a collar of long, brown bristles on its dorsolateral edge, leaving the ventral aspect devoid of bristles. They have 3 pairs of brown-colored segmented prothoracic legs, 4 pairs of short prolegs, and 1 pair of brown anal prolegs. They cannot tolerate temperatures above 25˚C or below 5˚C. The optimal range temperature is 20–25˚C with temporal distribution between July-August [11].

Previous pharmacological test revealed presence of histamine, 5-hydroxytryptamine and acetylcholine in the caterpillar hair, which is the most probable cause of urticaria in humans. A histamine-like substance has been isolated in Spilosoma lutea caterpillar hairs [8]. Other authors stated that hair extracts caused tissue damage by inducing histamine, proinflammatory products of cyclooxygenase, and nitric oxide [15]. Formic acid has been found in Notodontid caterpillars hair which causes skin blistering after direct contact [16]. Caterpillar setae have allergenic proteins such as thaumotopoein, which act directly on mast cell degranulation [1,17]. Fuzzy caterpillars are responsible for dermatitis, contact urticaria and anaphylactic reactions through IgE-mediated or non-IgE-mediated mechanisms [6]. Serum IgE to hair extracts has been found in the sera of forest workers exposed to Thaumetopea pityocampa caterpillars. Almost all workers developed urticaria, angioedema, or bronchial asthma after exposure [17].

Lepidoptera can cause immediate hypersensitivity reactions, delayed-type hypersensitivity or both. Intradermal injections causing immediate wheal-and-flare reactions have been demonstrated with E pseudoconspersa setal extracts [18]. Prick testing with extracts from Thaumetopoea caterpillars instigate significantly higher rates of positive testing in individuals with previous exposure to caterpillars compared to those without contact [19]. Patch testing with E chrysorrhea setae revealed erythema and edema within 5 hours, progressing to vesiculation at 72 hours [20]. Patch testing with setal extracts from E pseudoconspersa larva showed immediate and delayed-type reactions [21].

Management of lepidopterism is supportive. Topical application of anesthetic [3], corticosteroid and antihistamine may be given [22]. Cold compresses and calamine lotions provide partial symptomatic relief [23]. Warm compresses impregnated with sodium bicarbonate are likewise helpful. Early removal of adherent urticating hairs by applying adhesive tape or using forceps is recommended [16].

In conclusion, caterpillar envenomation is a fairly common environmental dermatitis, which is often overlooked by dermatologists. Diagnosis is often generalized as caterpillar dermatitis when in fact some cases should already be classified as Lepidopterism, in which management and prognostication may slightly differ. The role of the immune response to caterpillar exposure is still currently being investigated. Analyzing allergen similarities between species of Lepidoptera and cross-reactivity to related caterpillar may provide some insight on potential desensitization protocols. In tropical areas, where diversity of Lepidoptera is enormous, there is lack of documented caterpillar envenomation incidents and likely underrepresents the true number of cases. To the best of our knowledge, this case is the first reported cutaneous lepidopterism caused by Apona sp. caterpillar in the Philippines.

  1. Eaglemen DM (2007) Envenomation by the asp caterpillar (Megalopyge opercularis). J Clin Toxicol 1-5.


  1. Dugar B, Sterbank J, Tcheurekdjian H, Hostoffer R (2014) Beware of the caterpillar: Anaphylaxis to the spotted tussock moth caterpillar, Lophocampa maculate. J Allergy Rhinol 5: e113-e115.


  1. Haddad V, Lastória JC (2014) Envenomation by caterpillars (erucism): proposal for simple pain relief treatment. J Venomous Anim Tox Trop Dis 20: 21.


  1. Schmitberger PA, Fernandes TC, Santos RC, et al. (2013) Probable chronic renal failure caused by Lonomia Caterpillar Envenomation. J Venomous Anim Tox Trop Dis 19: 14.


  1. Paniz-Mondolfi AE, Perez-Alvarez AM, Lundberg U, Forne L, Reyes-Jaimes O, et al. (2011) Cutaneous lepidopterism: dermatitis from contact with moths of Hylesia metabus (Cramer 1775) (Lepidoptera: Saturniidae), the causative agent of caripito itch. Int J Dermatol 50: 535-541.


  1. Smith-Norowitz TA, Norowitz KB, Kohlhoff S, Kalra K, Chice S, et al. (2010) Immune response profiles after caterpillar exposure: a case report. J Inflamm Res 3: 45-51.


  1. Diaz JH (2005) The Evolving Global Epidemiology, Syndromic Classification, Management, and Prevention of Caterpillar Envenoming. Am J Trop Med Hyg 72: 347-357.


  1. Hossler EW (2010) Dermatologic manifestations of encounters with Lepidoptera: Caterpillars and moths part 1. J Am Acad Dermatol 62: 1-10.


  1. Spiegel W, Maier H, Maier M (2004) A non-infectious airborne disease. Lancet 363: 1438.


  1. Gottschling S, Meyer S, Dill-Mueller D, Wurm D, Gortner L (2007) Outbreak report of airborne caterpillar dermatitis in a kindergarten. Dermatology 215: 5-9.


  1. Singh P (2014) Eupterotidae apona Ligustrum Silk Moth.India biodiversity portal 2014.


  1. Farangs Gone Wild (2015) Caterpillars of Thailand.


  1. Holloway JD (1987) The Moths of Borneo, Part3: Lasiocampidae, Eupterotidae, Bombycidae Brahmaeidae, Saturniidae Sphingidae. The Malay Nature Society and Southdene Sdn. Bhd, Kuala Lumpur.


  1. Nassig WA, Rolf G. The nomenclature of the family-group names of Eupterotidae (Bombycoidea). Nota lipid 30: 315-327.


  1. Lunardelli A, Leite CE, Pires MG, de Oliveira JR (2006) Extract of the bristles of Dirphia sp. increases nitric oxide in a rat pleurisy model. J Inflamm Res 55: 129-135.


  1. Hossler EW (2010) Dermatologic manifestations of encounters with Lepidoptera: Caterpillars and moths part 2. J Am Acad Dermatol 62: 14-28.


  1. Bonamonte D, Foti C, Vestita M, Angelini G (2013) Skin Reactions to PineProcessionary Processionary Caterpillar Thaumetopoea pityocampa Schiff. Sci World J.


  1. Vega J, Vega JM, Moneo I, Armentia A, Caballero ML, et al. (2004) Occupational immunologic contact urticaria from pine processionary caterpillar (Thaumetopoea pityocampa): experience in 30 cases. J Contact Dermatitis 50: 60-64.


  1. Costa RM, Atra E, Ferraz MB, da Silva NP, de Souza JM, et al. (1993) ‘‘Pararamose’’: an occupational arthritis caused by lepidoptera (Premolis semirufa). An epidemiological study. Rev Paul Med 111: 462-465.


  1. de Jong MC, Bleumink E, Nater JP (1975) Investigative studies of the dermatitis caused by the larva of the brown-tail moth (Euproctis chrysorrhoea Linn.) I. Clinical and experimental findings. J Arch Dermatol Res 253: 287-300.


  1. Natsuaki M (2002) Immediate and delayed-type reactions in caterpillar dermatitis. J Dermatol 29: 471-476.


  1. Cuevas P, Angulo J, Giménez-Gallego G (2011) Topical treatment of contact dermatitis by pine processionary caterpillar. BMJ Case Reports J.


  1. Bowles DE, Swaby JA (2015) Field guide to venomous and medically important invertebrates affecting military operations: identification, biology, symptoms, and treatment.
  2. Neustater BR, Stollman NH, Manten HD (1996) Sting of the puss caterpillar: an unusual cause of acute abdominal pain. South Med J 89: 826-827.