Discussion
Aural myiasis is an uncommon infestation of the ears. Myiasis is
categorized as an obligatory or facultative infestation. In the former,
the host, most frequently a goat or sheep, is an essential component of
the maggots’ life cycle, but in the latter, it is not [10]. Fly
species from the Calliphoridae, Sarcophagidae, Gastrophilidae,
Cuteribridae, Musca, Famina, Chrysomyia, and C. vicifiia families cause
myiasis. The commonest genera causing myiasis belongs to Sarcophagidae
[11]. Myiasis is more common in tropical and subtropical regions,
and most cases recorded in the United States and Europe are in tourists
coming back from these regions. In moderate climates, the larvae of
cosmopolitan dipteran flies accidentally parasitize human skin
(Hypoderma bovis and Gasterophilus intestinalis), the nose, paranasal
sinuses, pharynx, and ears (Calliphora species, Lucilia sericata, and
Musca domestica), the alimentary tract and urogenital system (Fannia
canicularis), and the eyes, orbits, and periorbital tissues. [12].
Medical entomologists, veterinarians, and doctors frequently find it
helpful to further categorize myiasis into several categories according
to the body area and tissue affected [13]. That means traumatic
myiasis, oral myiasis, aural myiasis, ophthalmomyiasis, enteric myiasis,
urogenital myiasis, and rectal myiasis. Previously, almost all
literatures have documented aural myiasis due to the infestation of fly
maggots. To our knowledge, no paper has been published on ear
infestation by adult flies. In contrast to those reports, this
particular case is worth reporting due to the rarest of all myiasis
cases.
According to the research, hosts are typically 60 years old, with a
male-to-female ratio of 5.5:1. The incidence of myiasis may be
associated with the level of sanitation currently in place, the density
of the current fly population, and the individual’s economic situation.
Patients who are intellectually handicapped, elderly, diabetic, chronic
purulent otitis media, homelessness, alcoholism, psychological disorders
or unwell, peripheral vascular disease as well as drug users, are more
vulnerable to attack. [14-16]. In our case, the patient is only 14
years old school girl and has no comorbid illnesses. However, reports of
newborn myiasis cases have also been made [17]. Human myiasis can be
mild and asymptomatic or severe and potentially fatal since larval
infestations of the eye, nose, and ears can enter the brain [18].
The same is true for this patient. She tolerated right ear pain over the
past eight years though she visited a number of health facilities.
Aural myiasis can cause a variety of distinct signs and symptoms, such
as otalgia, offensive otorrhea, aural fullness, bleeding, itching, a
roaring sound, tinnitus, vertigo, and furuncles of the external auditory
canal when larvae are present in the ear. Meningitis and hearing loss
can result from damage to the auditory meatus [11, 12, 19]. The
larval attack may cause damage to the ear canal’s surrounding tissue,
including the bones, and very rarely, death [7]. Either mechanical
tissue disruption or the larvae’s synthesis of the enzyme collagenase
can result in tissue damage. Because the feeding maggots from a single
egg batch may entice many additional ovipositing flies of numerous
species, resulting in the aggregation of thousands of eggs and larvae,
small, early infestations frequently grow into massive infestations with
life-threatening implications [20]. After the deposited larvae begin
to feed on the surrounding tissues, the symptoms appear. Usually, the
history and clinical examination, which will reveal the larvae in the
ear, are used to identify the infestation. Due to the fact that the
larvae are typically found close to the external auditory canal because
they need air to breathe, further testing to diagnose it is unnecessary
[21].
Most of the time, treating aural myiasis is as simple as removing the
larvae and irrigating the ear with one or more of the following
solutions: Alcohol, chloroform, normal saline, oil, ivermectin, or
iodine [9, 22-26]. Additionally, broad-spectrum preventive
antibiotics are typically used to stop subsequent infections. Under a
microscope, the larvae should be removed, and any remnants should be
thoroughly examined. Given that they all produce the same results, it is
difficult to determine which irrigation solution is better. The
irrigation’s usual purpose is to kill and remove any remaining larvae,
especially those that are difficult to see or reach on examination
[21]. Sometimes patients require surgical investigation to determine
the extent of the disease or to check for residual disease. In these
situations, mastoid exploration is typically carried out to determine
the degree of the infestation and, if any residue is discovered, it will
be eradicated [27, 28].