Oro‐nasal myiasis in a lymphoma patient

Abstract

A 27-year-old male previously diagnosed with extranodal NK/T-cell lymphoma, nasal type (ENKTLN), presented with recurrent unilateral epistaxis and palatal pain of 2 weeks duration. He had initially been treated with radiotherapy and chemotherapy according to the CHOMP protocol (cyclophosphamide, doxorubicin, vincristine, prednisone, methotrexate, leucovorin). Following disease progression, he had been treated with L-asparaginase and, finally, an autologous haematopoietic stem cell transplant had been performed a year before the current presentation. Ulceration and necrosis of the hard palate had been observed prior to the transplant and surgical debridement of necrotic areas had then been performed. Physical examination on admission showed the previously reported ulceration and necrosis of his hard palate and beneath this, living larvae were encountered (left). In addition there was an erythematous, swollen and warm region of the right side of the face, suggesting secondary cellulitis. On exploration of his nasal cavity, 60 larvae were encountered and manually removed. Examination of posterior spiracles from removed larvae by light microscopy was suggestive of Cochliomyia hominivorax (centre), the New World screw-worm fly. Computed tomography (CT) scanning of the paranasal sinuses (right) showed material of soft tissue density in the maxillary sinuses, ill-defined opacities with interposed aerated areas (larvae, white arrow) in the nasal cavity and an oro-nasal fistula (arrowhead). A diagnosis of oral and nasal myiasis with periorbital cellulitis was established. The patient was started on oral ivermectin, cefe-pime and metronidazole and the necrotic lesions of the palatal bone were surgically removed. The patient made a full recovery.Typically, ENKTLN is characterized by progressive midline facial destruction. As the tumour mass enlarges, invasion and destruction of structures of the upper anterior aerodigestive tract can occur, with the tissues becoming progressively necrotic. Occasionally, local extension from the nasal cavity causes destruction of the hard palate with a characteristic midline perforation. Without adequate hygiene and wound dressing, these ulcerated, necrotic lesions of the oro-nasal region are major predisposing factors for myiasis. Myiasis of the oronasal region is uncommon; it should be prevented in at-risk ENKTLN patients by educating patients and parents, mainly from rural areas and low socio-economic groups, about personal hygiene, adequate care of wounds, control of the fly population and maintenance of sanitation of the surroundings. Treating physicians should be aware of this potential complication in ENKTLN patients in order to ensure adequate prevention and treatment of this unpleasant condition.

Oral myiasis: Analysis of cases reported in the English literature from 1990 to 2020

“…Interestingly, an association of oral myiasis with malignant neoplasms has been reported elsewhere 14,26,35,41,51,69, 79,95,116 . Most affected individuals are from rural areas with low socioeconomic status.…”

“…Efforts were made to contact the authors of three studies; however, their articles could not be retrieved 17–19 . A total of 122 articles reporting 157 cases of oral myiasis were selected 2,5–14,16,20–129 …”

“…The articles were from India, 7,9,11,13,21,23,24,29,30,32–35,38, 41,45,50–52,65,66,68,70,71,73–76,82,87,91,93,99,100,105–110,113,116–118,120–122, 126,127,129 Brazil, 2,8,10,12,14,16,20,22,31,36,43,44,47–49,57–60,69,77–79,81, 84,85,90,92,95,101,102,104,112,115,123,125 Turkey, 6,28,37,42,54,61,62,124,128 Iran, 26,63,80,103,111 China, 39,40,88,96,119 Malaysia, 64,98 Colombia, 53 Israel, 5 Oman, 25 Yemen, 27 Czech Republic, 46 The Netherlands, 55 Italy, 97 USA, 56 UK, 86,89 Spain, 94 South Korea, 67 Pakistan, 72 Bangladesh, 114 and Mexico 83 (Figure 1).…”

“…Concerning the anatomical location, most lesions affected the buccal mucosa, extending to the chin or cheek 35,41,51,116 . The middle third of the face, alveolar region extending to the oropharynx, oronasal region, maxilla, and mandible may also be affected 14,26,69,79,95 . As stated by Girardi and Scrofernecker, 135 individuals with head and neck cancer are at risk to develop secondary myiasis.…”

“…Most affected individuals are from rural areas with low socioeconomic status. Information about male individuals (81.8%) with a mean age of 57.1 years (range: 27‐89 years), who were suffering from squamous cell carcinoma, 14,35,41,51,79,95,116 non‐Hodgkin lymphoma, 26 and extranodal NK/T‐cell lymphoma, nasal type, 69 has been documented. Concerning the anatomical location, most lesions affected the buccal mucosa, extending to the chin or cheek 35,41,51,116 .…”