Juniper Publishers-Journal of Ophthalmology
Abstract
Miasis refers to invasion into
the living tissues of humans and other mammals by the eggs or larvae of
flies from the order of Dipteria. The invasive parasitic larvae almost
invariably cause massive destruction of orbital tissue especially in
neglected patients accompanied by marked inflammatory reactions and
secondary bacterial infections. Infestation can be caused by multiple or
single larvae. We report a case of 50 yr post menopausal women who was
having squamous cell carcinoma of conjunctiva and was a neglected and
belonged to low socioeconomic status. The patient ultimately ended with
massive orbital miasis.
Keywords:Orbital Miasis; Carcinoma
Introduction
Orbital miasis is very rare worldwide. Miasis is a
term first introduced by F. W. Hope. Miai is a Greek word meaning ‘fly’.
Miasis refers to invasion into the living tissues of humans and other
mammals by the eggs or larvae of flies from the order of Dipteria [1,2].
The invasive parasitic larvae almost invariably cause massive
destruction of orbital tissue especially in neglected patients
accompanied by marked inflammatory reactions and secondary bacterial
infections. Infestation can be caused by multiple or single larvae [3].
Nursing staff, medical and paramedic staff should be aware of this
condition, particularly in high risk cases like immobile, open wound and
skin malignancy patients.
Case Report
50 year old postmenopausal, normotensive, non
diabetic, chronic hukka smoker patient comes to the accident and
emergency department of SMHS Hospital with a complaint of blood stained
discharge from the left eye and worms seen in the same eye (Figure 1).
On examination the upper and the lower lids of the same eye were
swollen, thickened and hard and could not be closed. The eye ball and
the ocular tissue could not be seen. There was blood stained discharge
and numerous live active worms in the left orbit. There was active
oozing of blood on the left side. Orbital miasis was diagnosed. After
going through the records of the patient, we came to know that patient
was already diagnosed as a case of left poorly differentiated squamous
cell carcinoma of the conjunctiva. CECT head showed soft tissue density
mass with no bone invasion. MRI shows 5x4cm extracranial intraorbital
mass with intraorbital component adherent to left lateral rectus muscle
with left preauricular lymphadenopathy. The staging of tumor was T4 N1
M0. After cleaning and debridement of left orbital cavity the patient
was referred back to the parent institution for emergency exentration
and radiotherapy.
The maggots were identified as chyrosoma bezziana.
Discussion
Ophthalmomiasis is a rare form of eye disease and
massive orbital or ocular miasis is even rarer [1,3-6]. Flies are small
vingid orthopods of the class insecta. Some are biological or
mechanical vectors of protozoal viral, bacterial for helminthic disease.
Miasis in humans may be benign to asymptomatic or may result in mild to
violent disturbances even death. Orbital miasis is the least common
form of ophthalmomiasis.
By going through the literature we found very less
cases of orbital miasis. Children and elderly persons or dementia
patients who could not adequately take care of themselves are usually
the victims. Most reported cases have belonged to the lower class of
society being farmers, labours or beggars. In children, gonococcal
conjunctivitis and in adult’s periocular ulcerated skin cancers may
predispose to larval infestation3. Orbital miasis occurs when large
number of diptherous larvae known as flies invades and destroy orbital
contents. Ophthalmo-miasis may result in complications ranged from minor
ocular ulceration to complete blindness and even death [7]. Common
ophthalmomiasis inducing agents are cochhomyia hominivorax, hypoderma
bovis, caliphora vomitoria, wohlfartia magnifia and chyrosoma. Bezziana
the maggets identified in our patients belonged to C. Bezziana.
Diagnosis is based on microscopic examination of the sliced caudal ends
of the larvae (preserved in 70% alcohol or formalin). A dichomatous key
is used to identify the number of interior spiracet opening and shape of
body part [8]. Discharge associated with chyrosoma Bezziana foul smells
and bloody.
The main predisposing factor for infestation in our
patient was bed of necrotic tissue, provided by squamous cell carcinoma.
Other important factors were lack of self care, general ignorance, low
socioeconomic status and poor hygiene.
Any skin ulceration like diabetic, neurotrophic and
malignant ulcers in the exposed areas in these patients are a risk
factor and should be treated [9].
Miasis is not a common disorder in humans and it
affects primarily wounds of skin, infection with purulent secretion and
blood and body secretions are most common factors that attract flies.
Conclusion
Orbital miasis is a rare disease, which is marked by
inflammatory reactions and secondary bacterial infections. Life
threatening consequences like intracranial invasion may also occur. Old,
debilitated and neglected patients are more prone to such disease.
Malignant growths often form scaffolding for such infections to occur.
Figure 1: The maggots were identified as chyrosoma bezziana.
For more articles in JOJ Ophthalmology please click on:
https://juniperpublishers.com/jojo/index.php
https://juniperpublishers.com/jojo/index.php
No comments:
Post a Comment