CASE REPORT Urinogenital Myiasis From Blow Fly in a Pakistani Child Farrah Zaidi, Naheed Ali and Muhammad Khisroon ABSTRACT Herein is reported the first case of urogenital myiasis from Peshawar, Pakistan. Third instar blow fly larvae were recovered from the urinogenital tract of a 5-year old female child. The larvae were identified as Chrysomya bezziana (Villeneuve), using Light and Scanning Electron microscopic techniques. The study brings into focus the subject of human myiasis, about which little is known in Pakistan. Key Words: Human myiasis. Chrysomya bezziana. Pakistan. Urogenital myiasis. INTRODUCTION (Phylum: Arthropoda, Class: Insecta, Order: Diptera, Myiasis is a parasitic disease of humans and other Family: Calliphoridae, sub-family Chrysomyiinae, vertebrate animals, caused by dipterous larvae. The Genus: Chrysomya) and the doctor was informed. condition has been studied widely in humans, farm Examination of the urogenital tract showed no further animals, and pets.1 In humans, the disease manifests infestation and superficial ulcers with a mild purulent itself in various forms depending on the site of tissue ulcer slough. The wound was cleaned and disinfected, it infestation by larvae such as ocular, nasopharyngeal, did not require major debridement. Three consecutive oral and urinogenital myiasis.1-3 Most of these forms follow-up examinations of the patient, one after a are usually associated with poor general health and fortnight and the other two after a month's interval, hygiene.3 Larvae of more than 50 fly species are showed rapid healing and no signs of worm infestation. implicated in myiasis.2 Important species include The parents were strictly advised to keep the wound Chrysomya bezziana, Chrysomya megacephala, covered in order to prevent access of gravid female Chrysomya rufifacies and Lucilia sericata;4 all being flies and recurrence of condition. Possibility of a reported from Pakistan.5 secondary urinary tract infection was ruled out by urine examination. This study describes the first report of human myiasis by Chrysomya bezziana from Peshawar, Pakistan. The larval specimens were kept in 70% alcohol at Zoology Department. Specific identification of species was CASE REPORT performed in December 2014 using larval taxonomic keys. For scanning electron microscopic (SEM) A case of urinogenital myiasis in a 5-year old female observations, previously described protocol was used. child was brought to the attention of doctors at Khyber Teaching Hospital, Peshawar in 2009. The patient Larvae were identified as the obligatory parasitic screw belonged to a poor family living under unhygienic worm species Chrysomya bezziana. Each larva was conditions. The patient was referred to the gynaecology dirty white in color and about 6 - 7 mm in length. The OPD. She presented with signs and symptoms of a body was smooth without any fleshy processes urinary tract infection. She complained of a dull lower protruding out. The posterior spiracles had an open abdominal pain, vaginal itching and severe pain, peritreme with three slits, revealing that the larvae were dysuria, burning micturition and increased frequency. full grown third instars (Figure 1a). The anterior spiracle Her parents also gave history of nocturnal enuresis, and had 5 papillae (Figure 1b), which is a species diagnostic that 5 larvae were found on the bed in the morning. feature of Chrysomya bezziana. The larvae were sent by the inquisitive family to the Department of Zoology, University of Peshawar, following instructions of the concerned doctor. The specimens were immediately identified as screw worms Department of Zoology, University of Peshawar, Peshawar, Khyber Pakhtunkhwa. Correspondence: Dr. Farrah Zaidi, Assistant Professor, Department of Zoology, University of Peshawar, Peshawar 25120, Khyber Pakhtunkhwa. Figure 1: (a) Light micrograph of third instar larva of C. bezziana. Caudal E-mail: [email protected] view of contiguous posterior spiracles displaying three slits each. (b) Scanning electron micrograph of anterior spiracle of a third instar Received: February 17, 2015; Accepted: December 01, 2015. Chrysomya bezziana. Journal of the College of Physicians and Surgeons Pakistan 2016, Vol. 26 (Special Supplement 1 of Case Reports): S35-S36 S35 Farrah Zaidi, Naheed Ali and Muhammad Khisroon DISCUSSION investigated and reported in medical literature. Two Chrysomya bezziana, known as old world screw worm, studies, one describing urinogenital myiasis by black 8 is an obligate parasitic species infesting host wounds blow-fly Phormia regina, and another detailing 9 during its larval stages.4 It is a blow fly belonging to ophthalmic myiasis by sheep bot fly Oestrus ovis, have family Calliphoridae, Order Diptera (Class Insecta). Blow previously been reported from Karachi, Pakistan. flies are a nuisance,6 like their more known relatives, the This is the first study reporting C. bezziana myiasis in house flies. A major risk factor in acquiring myiasis is humans from Peshawar, Pakistan. Further studies are poor hygiene.3 The patient suffering from myiasis in our required to gain insight about the prevalence of this case had personal hygiene issues. She came from an condition in Pakistan. area of Badaber with poor sanitation and high fly populations. REFERENCES The blow fly C. bezziana starts its life cycle by finding 1. Verma P. Cutaneous myiasis in an infant with cerebral palsy. suitable host. It lays eggs on dry edges of wounds, Indian J Dermatol 2014; 59:310. depositing several layers of egg masses. Eggs hatch in 2. Wadhwa V, Kharbanda P, Rai S, Uppal B. Urogenital myiasis 10.5 hours at 37°C, after which, the first-instar larvae due to Chrysomyia bezziana. 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