Report of a rare case of severe allergic reaction due to nasal myiasis and a brief review of the literature in Turkey

Abstract

Myiasis is defined as infestation of a mammal by fly larvae. It may occur on either living tissues (primary myiasis) or dead tissues (secondary myiasis). In this report, we present a patient with myiasis with an extremely rare clinical manifestation and severe allergic reaction, and we review the literature in order to reveal the current status. A 20-year-old female patient was admitted to our emergency department due to rush on face, cough and shortness of breath. The maggot came out of her nose was identified as Oestrus ovis. With a diagnosis of severe allergic reaction due to myiasis, she was treated diphenhidramine, prednisone and inhale albuterol in the emergency department. After treatment and further investigation, she was discharged with full recovery. Myiasis is a rare cause for severe allergic reaction in patients with definite diagnosis. Immediate diagnosis and treatment are milestones in preventing bad outcomes.

Introduction

Myiasis is a term defining condition characterized by infestation of a mammal by fly larvae in order to feed on its tissues.¹ While, in primary, myiasis larvae feed on living tissues, in secondary, myiasis larvae feed on dead tissues.² Human myiasis is often classified according to the area infested such as cutaneous, oral, ocular, nasal, urogenital and gastrointestinal myiasis. Presentations on the skin are localized furuncular myiasis, creeping dermal myiasis, as well as wound and body cavity myiasis.³

When nostrils are invaded by dipteran larvae, it is called nasal myiasis.⁴ Nasal myiasis is thought to be underreported in tropical countries. However, it is endemic due to warm and humid environment. The condition is commonly seen in older female people due to decreased ability to ward off the flies themselves. It is common in low socioeconomic classes that suffer from poor nasal hygienic conditions.^5,6

Nasal myiasis may cause embarrassment and stress to the patient, relatives and health care providers. In addition, it has a wide range of symptoms from mild to severe such as foreign body sensation, itching, nasal discharge, sneezing and even more severe respiratory manifestations and penetration of larvae into the brain.⁷ The most useful method for preventing the myiasis is extracting the flies.⁸ In this report, we present you a rare case of myiasis resulting in severe allergic reaction and aim to clarify the current status of myiasis in Turkey in the light of the literature.

Case report

A 20-year-old female patient was admitted to our emergency department (ED) due to rash on face, cough and shortness of breath. From the anamnesis, it was understood that she was lying near a tree on the grass in a park. Suddenly, she felt itching on her nose. After a sneeze, she recognized that a maggot has blown out of her nose on the handkerchief she used. And then, she suddenly developed rash, dyspnoea and shortness of breath. On admission to our ED, she was hypotensive (90/60 mmHg) with a heart rate of 90 beats/min and a saturation of 96% by probe. She had a slightly altered mental status. On medical history, she had allergy to an unknown origin and she was under improper medication. After the maggot on the handkerchief was investigated by a parasitologist, a prediagnosis of severe allergic reaction due to myiasis was made (see Figure 1 for segmented larva with oral hooks in the first segment). On auscultation, she had stridor and wheezing. Blood tests were obtained and they did not reveal any abnormalities. A sinus graphy and a brain computed tomography for a possible sinus and brain infestation were performed, and they also did not reveal any abnormalities. She was treated by 50 mg diphenhidramine IV, 60 mg prednisone IV and 2.5 mg inhale albuterol. Following treatment, shortness of breath and rush improved. After her symptoms improved, a consultation with ear–nose–throat specialist was performed, and the patient was evaluated via rigid nasal endoscopy. Any residual larvae could not be determined. After follow-up, the patient was discharged with full recovery.

Figure 1.

Oestrus ovis as a cause of nasal myiasis.

Discussion

Myiasis takes root from the ancient Greek word ‘myia’ which means fly. It is known to be an infestation of the tissues and organs caused by fly (diptera) larvea.⁹

Some fly species lay their eggs on intact or damaged tissues of humans. When the eggs convert to larvae following hatching, myiasis develops. Usually, the predisposing factor in the occurrence of the disease is lack of hygiene.¹⁰ In our case, socioeconomical status of the patient was high, which means that the disease is a threat for everyone in the society regardless of personal hygiene or social status.

Nasal myiasis is known to be a self-limiting infestation.¹¹ In a report of nasal infestation of Oestrus ovis, it was stated that the disease was characterized by local inflammation of the mucosa and by sneezing or by manual extraction of the larvae from the cavity, and the larvae could be eliminated spontaneously usually without leaving sequelae.^12,13 Nasal myiasis in our case also had O. ovis infestation; however, severe allergic reaction has developed in our patient. If the treatment had delayed, it was possible to have bad outcomes for the patient.

Commonly, the infestation lasts 2 weeks and causes moderate-to-severe nasal discomfort with obstruction, rhinorrhoea and a burning sensation. Allergic reaction due to nasal O. ovis infestation requiring hospitalization is known to be an unusual presentation.¹¹ In our case, severe allergic reaction accompanied with asthma-like symptoms occurred and aggressive treatment was required.

The clinical and pathological infestation of myiasis in human depends on the type of flies, the mode of invasion by the larvae, the degree and type of migration after invasion, the stage in the life cycle of the fly, including the type and number of larval molts in the host, and the topographical site of invasion. These flies can cause disease in humans, with living on rotten tissue (maggots) or larvae crawl under the skin. Myiasis treatment, according to its type, is to be performed as soon as possible, with application of lateral pressure and suffocation by occlusion of the punctum with mineral oils, petroleum jelly or pork fat. Also, more-invasive interventions, such as surgical excision, may be necessary.¹⁴ In our case, any residual larvae could not be determined. Besides, in our case, myiasis has developed on healthy nasal cavity tissue instead of a wound.

For prevention from the disease, environmental health is important. In order to control myiasis, population of the flies must be controlled both in the open areas and health facilities. Enhancing environmental health standards in living and working places by public education about myiasis and the role of flies in the pathogenesis of the disease may play an important role in prevention and management of myiasis.⁴

Although generally the parasite is known to be seen in patients with mental retardation and/or accompanying psychiatric disorders, elderly individuals, those with poor self-care and hygiene and those with immune system disorders,¹⁵ our report revealed that the disease may also be seen in healthy subjects. Data on myiasis in the literature are mainly based on case reports in Turkey. It is known that aural, ophthalmic and wound myiases are the most commonly seen types of myiasis reported in Turkey. The most common species was Wohlfahrtia magnifica.^10,15–17 İnce et al.¹⁸ reported a case of respiratory myiasis following aspiration of the larvae.

O. ovis is known to be the most common reason for ophthalmomyiasis externa. Koylu et al. reported a case of ophthalmomyiasis externa – the infestation of conjunctiva by the larvae of O. ovis – and proposed a novel method of treatment by 1% drop of cyclopentolate – a parasympatholytic anticholinergic agent – which might make the collection of larvae easier.^19–23 The disease may be confused with bacterial conjunctivitis causing delays in treatment.²⁴

Demirel-Kaya et al.²⁵ presented a case of a patient with a wound due to squamous cell carcinoma from whom 200 larvae were collected and identified as Lucilia sericata. In another report by Bayindir et al.,²⁶ a wound of the head and neck region due to squamous cell carcinoma presented with cutaneous myiasis, and was treated with antisepsis, larval removal and general care preventions. It is also known that L. sericata is also used for maggot debridement therapy after sterile maggots are produced in university laboratories and by industrial institutions. The therapy is based on the wound debridement and disinfection of the wound.²⁷

Demir et al. reported a case of a case of urogenital myiasis in a 10-year-old girl who was admitted due to pruritus and dysuria. Psychoda albipennis was the causative agent which is responsible for most of the cases of myiasis reported from Turkey.^26,28–31

Myiasis that develops in a hospital setting is referred to as nosocomial myiasis. It is mostly seen in intensive care patients with hypoesthesia or disturbed consciousness, preventing the patient from sensing contact from the fly.^32,33 Ergün et al.³⁴ presented a case of nosocomial wound myiasis by Sarcophaga species in patient with biliary tract injury caused by laparoscopic cholecystectomy. Polat et al.³⁵ reported two otomyiasis cases caused by Sarcophaga species.

In a report, it was stated that a patients with preseptal cellulitis presented with a larva on the eyelid.³⁶ Also, a gingival myiasis in a 2-year-old child was reported by Arslan et al.³⁷

Conclusion

Physicians must be aware of myiasis particularly in patients with poor hygienic condition and persistent infections. Besides, it should be remembered that not only people with open wound or predisposing factors living in rural or tropical areas but also healthy subjects living in city centers are under risk of myiasis.