Human dicrocoeliosis with urticaria: A case report from India.

Human dicrocoeliosis caused by Dicrocoelium dendriticum is reported sporadically from various parts of the world. D. dendriticum, a liver fluke has a complex life cycle with two intermediate hosts‒the land snail and the ant. True human infection occurs by ingestion of the second intermediate host, but spurious infections have occurred after consumption of undercooked animal liver. We report a case of a 20-year-old female who presented with abdominal pain, diarrhea, and itchy skin rashes all over the body. Stool microscopy revealed numerous eggs of D. dendritricum. A brief discussion of the medical literature is presented. Copyright:

INTRODUCTION

Liver flukes are one of the causes of diarrhea in humans. Ruminants (cows, bulls, sheep, and deer) are the usual definitive hosts for Dicrocoelium dendriticum, although other animals (ex-goats, yaks, and rabbits) and humans can serve as definitive hosts. Snails and ants are the first and second intermediate hosts, respectively.[1] Cases of human dicrocoeliosis have been reported from various parts of the world, most commonly from Europe and Middle East.[23] Although dicrocoeliosis has been reported in animals from India,[45] to the best of our knowledge, no human case has been reported so far from India.

CASE REPORT

Our patient was a 20-years-old female who presented with abdominal pain, diarrhea, and itchy skin rashes all over the body [Figure 1]. On physical examination, the patient had epigastric tenderness. There was no eosinophilia; however, the total white blood cell count was slightly raised (11,560/cumm). Alkaline phosphatase, alanine aminotransferase, aspartate transaminase, and direct and indirect bilirubin levels were in the normal range. C-reactive protein was raised (38.90 mg/L). Stool microscopy of the patient revealed numerous eggs of D. dendriticum [Figure 2]. The eggs were asymmetric, dark brown, thick walled, and had an operculated shell. To confirm the result of the previous stool examination, stool examination was repeated the next day also. Eggs were seen on microscopic examination on 2nd day as well. The patient consumes goat meat, chicken, and fish regularly but denied eating meat in the last 7 days of stool examination; thus, chances of psuedoparasitosis are ruled out. However, the patient did not recall consuming any food items or water contaminated with ants. The patient was treated with albendazole 400 mg and nitazoxanide 500 mg for 3 days and 6 days, respectively. Other symptomatic treatment for abdominal pain and urticaria was also given. The patient was almost free of symptoms and stool examination for the parasite was negative on 3rd day. However, the patient reported twice with similar complaints of itchy skin rashes without gastrointestinal symptoms within 1 month. She was relieved after symptomatic treatment. Stool routine and skin biopsy could not be done during her visits. Follow-up was taken and the patient does not report any complaints thereafter.

Figure 1

Rashes over hand

Figure 2

Dicrocoelium eggs (magnification ×40)

DISCUSSION

Embryonated eggs of D. dendriticum are shed in the feces of the definitive host. The eggs are ingested by a snail (first intermediate host). When the miracidia hatch, they migrate through the gut wall and settle into the adjacent vascular connective tissue, where they become mother sporocysts. The sporocysts migrate to the digestive gland where they give rise to several daughter sporocysts. Inside each daughter sporocyst, cercariae are produced. The cercariae migrate to the respiration chamber where they are shed in slime ball from the snail. After a slime ball is ingested by an ant, the cercariae become free in the intestine and migrate to the hemocoel where they become metacercaria. After an ant is eaten by the definitive host, the metacercaria excyst in the small intestine. The worms migrate to the bile duct where they mature into adults. Humans can serve as definitive hosts after accidentally ingesting infected ants.[1] The young flukes move to the liver and start laying eggs after 10–12 weeks. Although the subclinical form predominates, it can produce chronic cholangitis and dilatation, swelling, or adenomatous proliferation in the bile ducts.[6] Most reports of human infection by D. dendriticum originate in Europe and Middle East, where the lancet fluke is a common parasite in sheep and cattle. The most favorable climate condition for the infection of the definitive host is autumn as there are abundant pastures, humidity, and a large amount of mollusks discharging cercariae.[7] Dicrocoeliosis in animals from India has been reported from northern and central regions such as Himachal Pradesh, Kashmir, and Nagpur.[458] A study conducted by Veterinary College in Nagpur revealed the incidence of 8.33% in captive deer.[4] Our patient consumed meat regularly; however, she did not recollect drinking contaminated water or eating salads, raw vegetables, or fruits containing infected ants. The patient presented with typical symptoms such as abdominal pain, diarrhea along itchy skin rashes all over the body. The patient also reported twice with similar complaints of itchy skin rashes without gastrointestinal symptoms within 1 month. Dicrocoeliosis associated with urticarial rashes has also been reported by Sing et al. in an Afghani immigrant.[9] Our patient responded to albendazole and nitazoxanide.

It would be interesting to know the prevalence rates of parasitization of this trematode in herbivore animals in our region currently.

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The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.