Myiasis in an 89-year-old man with non-hodgkin lymphoma.

Myiasis is due to the opportunistic dipterous larvae feeding on viable or necrotic tissues of the host occurring throughout the world. We report a case of oral myiasis in an immune-compromised patient suffering from non-Hodgkin lymphoma. We would like to emphasize that such ectoparasitic infections may happen in immunocompromised patients and oral hygiene should be evaluated in all of these patients.

Introduction

Myiasis is due to the opportunistic dipterous larvae feeding on viable or necrotic tissues of the host frequently occurring throughout the world. Here we report a case of oral myiasis in an immune-compromised patient suffering from non-Hodgkin lymphoma to emphasize the importance of paying attention to oral hygiene in immune-compromised patients.

Case Report

An 89-year-old man with the previous history of dementia and non-Hodgkin lymphoma presented with sudden initiation of tachypnea, tachycardia, and decreased level of consciousness. In physical examination, coarse crackles were auscultated all over the lungs and the patient was febrile. In intraoral examination, the following scheme was seen. He was intubated and mechanically ventilated due to hypoventilation and loss of protective airway reflexes. In the laboratory evaluations, no noticeable abnormality was detected except for leukocytosis (WBC=16000) and CRP of 4+.

Our patient was with the previous history of dementia and follicular lowgrade lymphoma of stage Ia on wait and watch follow-up. On the diagnosis of myiasis, lidocaine spray accompanying with spray of hydrogen peroxide 3% were applied for killing of the larvae. The inter-denture spaces were filled with vaseline. The patient was intubated in order to prevent further migration and aspiration of the larvae. He was put on intravenous midazolam with the dose of 1 mg per hour for maintenance of unconsciousness. Cefepime and clindamycin were initiated with the dose of 2g, BD and 600 mg, TDS, respectively. The patient died 7 days later from sepsis.

Discussion

Myiasis is due to the opportunistic dipterous larvae feeding on viable or necrotic tissues of the host (Sankari and Ramakrishnan 2010). Of the many types of myiasis, furuncular myiasis is the most common (Diaz 2009). Since oral tissues are not permanently exposed to the external environment, oral myiasis is less common than cutaneous myiasis (Rossi-Schneider 2007). It has previously been reported in dental extraction, nosocomial infection, drug addiction, visits to tropical countries, psychiatric patients, and conditions that cause prolonged mouth opening including senility, alcoholism, and mental retardation.

Persistent mouth opening facilitates the deposition of the eggs by the adult fly (Sankari and Ramakrishnan 2010). Treatment of the condition generally includes injection of lidocaine into the draining lesions, occlusive coating of vaseline (petroleum) ointment, clear fingernail polishing, tobacco tar, and surgical or vacuum extraction of the larvae in cases of unsuccessful occlusive therapy (Diaz 2009). However, after removal of the larvae, it seems that the tissues recover with no subsequent complications and further need for treatment (Droma et al. 2007). This case shows the development of an ectoparasitic infection in an immunocompromised patient and shows the importance of paying attention to oral hygiene in these patients.