by Dr. Mahadhir Alhady & Professor Chua
A previously well 9-year-old boy from a border town with Kalimantan, Indonesia, some 100 Km from our hospital, complained of a two-week history of bloody discharge in his right ear. The local doctor noted ulceration of the right ear canal and the presence of live maggots. He was referred to our otolaryngologist who removed 45 maggots from the right middle ear cavity under general anaesthesia. While recovering at the hospital, the patient’s right eye was noted to be red. He was referred to our eye department. Apart from a right red eye, his vision was normal. Slit-lamp examination showed a breach in the the superonasal bulbar conjunctiva (Figure 1) and a live maggot could be seen lying deep in the wound. Attempt to remove the worm was unsuccessful as the patient was unable to cooperate. Under general anaesthesia, the conjunctival wound was extended to expose the maggot (Figure 2 and 3) which was removed whole with a pair of forceps. The worm measured 12mm (Figure 4). Based on the shape, mouth and tail part of the maggot, it was identified as the larva of Chrysomya bezziana (screwworm fly).
Figure 1. The black arrow indicates site of the burrow.
Figure 2. The conjunctiva is incised to expose the worm.
Figure 3. More body of worm was exposed through deeper dissection.
Figure 4. The whole length of the worm measured about 12mm.
a. What is ophthalmomyiasis?
b. How does Screwworm infestation occur?
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