Vulval myiasis: An unusual presentation of a rare entity in an adolescent female.

Human myiasis refers to parasitic infestation of body tissues by larvae of several fly species. The entity has a simple management. Human myiasis is well-documented in the literature however genital myiasis in females is scarcely reported in the literature. We hereby report this entity in an adolescent female who presented with urinary retention and concomitant urinary tract infection.

INTRODUCTION

Human myiasis refers to the disease caused by the infestation of human body tissue (skin, necrotic tissues or natural cavities) by larvae of several fly species. These fly larvae commonly known as maggots can invade healthy tissues leading to furunculoid or primary myiasis as well as necrotic tissues leading to cavitary or secondary myiasis.[1]

Primary variety occurs on uncovered body parts such as arms and legs while the secondary type involves sites in head, e.g. nasal sinus, auditory canal, ocular globes etc. Infestation in genital region is very rare with only few reports in literature. Male to female ratio is 5.5:1.[2]

We hereby present a case of vulval myiasis in young adolescent female who had concomitant urinary tract infection (UTI) and presented with urinary retention.

CASE REPORT

The present case report is about a 17 year old adolescent girl who was brought to casualty by her father,with the complaints of excessive pain,perineal itching and retention of urine for 12 hours. History started a month back with perineal itching which gradually increased in severity and pain supervened over next 2 weeks which led her to the primary health center where repeatedly (on 3 successive visits over 10 days) antihistamines and analgesics were prescribed without any single attempt of local examination. Later she developed urinary frequency followed by urinary retention for which she was referred to higher center. Her last menstrual period was 20 days back with normal menarche but history of hypomenorrhea for last 1 year. She was unaware of the menstrual hygiene practices. Moreover, she used home-made cloth pads during her periods which she used over again and again after washing and drying over 3-4 cycles. She was illiterate, motherless child of low socio-economic status, had fifth birth order with four elder brothers. All family members were daily wage workers living in one room house sharing a common toilet without regular water supply.

On examination, she was thin built, pale, dehydrated, with pulse rate of 100/min, blood pressure of 100/60, respiratory rate of 20/min with anxious look and strong putrid smell. Her temperature was 102°F. On per abdominal examination, suprapubic bladder lump corresponding to 14 weeks gravid uterus was found. Local examination of vulval, peri-vulval and periuretheral region showed excoriation along with edema and superficial sloughing with maggots emerging through, predominantly on right side with a very strong putrid smell [Figure 1]. Further examination was not possible owing to severe pain. She was given injection paracetamol, which brought down her temperature following which she was taken up for examination under Anaesthesia under short general anesthesia (intravenous sedation using injection Ketamine 25 mg, oxygen through face mask and injection midazolam 1 mg). Betadine cleaning followed by removal of superficial crust and slough was done [Figure 2]. Beneath it was ulcerated cavity of about 3 cm × 3 cm mainly over right labia minora extending just up to the hymenal ring from which 50 maggots were removed using anatomic tweezers. Thereafter turpentine oil was applied over it and along with magnesium sulfate ointment over the surrounding edema. The urinary retention was relieved by indwelling catheterization which was kept in situ for next 1 week until local edema resolved. In view of the presence of fever and local infection, the patient was started on parenteral antibiotics (injection ceftriaxone, metronidazole and amikacin) after sampling. Her hemoglobin was 6 g percent, total lymphocyte count was 13,000. Her Human Immunodeficiency Virus (HIV) status was negative. Vulval swab was sent for culture and sensitivity. Urine (catheter sample) was sent for routine and microscopic examination and culture and sensitivity. Urine examination showed pus cells in full field and urine as well as vulval culture showed growth of Escherichia coli sensitive to ceftriaxone and amikacin. The patient became afebrile on the 3rd day of antibiotics which were continued over next 7 days.

Figure 1

The predominantly right vulval involvement with overlying sloughed skin and superficial crusting with maggot creeping through

Figure 2

Photograph of same site after cleansing and removal of overlying sloughed skin showing ulcerated cavity full of maggots

The wound was cleaned daily, 40 dead maggots were removed the next day and 15 the following day after turpentine oil application. Patient was kept on high protein diet, oral hematinics and vitamin supplementation in view of her low immunity and nutrition status. Finally, at the end of 30 days, the wound healed by cicatrization and fibrosis.

CONCLUSIONS

Chrysomia bezziana is the most common cause of cutaneous myiasis in India, but usually infests wounds and mucous membranes. The predisposing and risk factors for human myiasis include open wounds, poor hygiene, advanced age, psychiatric illness, diabetes, vascular occlusive disease and physical handicap, rural background, low socio-economic status, ignorance of hygienic practices and homelessness.[3]

Socio-demographically this condition being prevalent in low socio-economic and rural settings, these patients often seek first medical attention by medical practitioners, in periphery of big cities or rural areas, who might not be aware of importance of getting it documented or published, hence, the condition seems to be under-reported. Many authors thus emphasize mandatory documentation and reporting of this condition.[2]

This case brings into light a rare but preventable condition. Simple primary and secondary prevention methods can be followed. Primary prevention methods include teaching simple hygienic practices to the females especially the adolescent population who will make the future reproductive age group. They should especially be sensitized about the menstrual hygiene and hence that the conditions like reproductive tract infections can be prevented.

Our patient, brought up as a motherless child, was probably never been taught or told of menstrual hygiene. Moreover, she used and reused same cloth over successive cycles by washing and drying. Probably the cloth was not washed off the blood which would have attracted flies which laid eggs over it which led to the condition. Moreover, her low nutritional status and anemia were responsible for hypomenorrhea and her low immunity levels made her infection prone. Her low socio-economic status, motherlessness, lack of privacy in home, sharing common toilet with inadequate water supply were the added risk factors.

Secondary prevention measures include early diagnosis and prompt treatment which was missing in this case. The authors thus hereby stress upon the need of careful gynecological examination to avoid missing the simple yet less common diseases. The patients suffering from genital disease must be subjected to serology testing for syphilis and HIV infection.[1] Our patient apart from usual presenting features of maggot infestation such as itching, local excoriation and edema also had concomitant UTI. The main presenting symptom was retention of the urine which was due to the severe periuretheral edema and pain.

Unfortunately, in our case the larvae were not sent for examination hence the species identification was not possible, but it has been suggested that the maggots removed should be submitted, in alive as well as in preserved form in alcohol or aldehyde for the purpose of species identification. Thus, the mandatory reporting and submission of the larva will help to have a better perspective in terms of epidemiology of the disease.

The disease has a benign course; treatment consists of local cleaning of the wound and removal of the maggots. Furunculoid myiasis can be treated by the occlusion of the wound with vaseline or nail enamel thus making the larvae immobilized, hence easily removable.[1] Although use of turpentine oil has been used for maggots infestation elsewhere in body, we have used it successfully in genital myiasis.

Few cases of genital myiasis have been reported so far in females from reproductive age group to elderly. Wadhwa et al. in their study have reported this entity in 45-year-old urinary incontinent female with carcinoma cervix with genitourinary myiasis.[4] Da Silva et al. in their study have reported this condition in a female with psychiatric disturbance.[5] Gonzαlez et al. reported a case of accidental infestation in a 27-year-old woman.[6] Saldarriaga et al. have reported in a uterine cavity infestation in an elderly female with genital prolapse,[7] while Dhawan et al. mentioned a patient with genital warts associated myiasis.[3]

This entity is completely preventable and has simple diagnosis and treatment. Responsibility on part of physicians is teaching hygiene practices to the population especially females and carrying out a simple gynecological examination in all patients with urogenital symptoms.