A 5-year-old boy, who had arrived in Canada from a refugee camp in Thailand 3 months earlier, presented to a community hospital with 2 weeks of abdominal pain and decreased oral intake, and 1 day of vomiting white worms.
On examination, the patient was found to have previously undiagnosed physical features of trisomy 21, including low-set ears, flat nasal bridge, macroglossia and bilateral transverse palmar creases. Results from serological testing showed mild transaminitis (alanine transaminase 68 [reference < 50] U/L and aspartate transaminase 86 [reference < 36] U/L), elevated gammaglutamyl transferase (254 [reference 10-22] U/L) and elevated lipase (168 [reference 6-51] U/L). Bilirubin, international normalized ratio, albumin and kidney function were normal.
An abdominal radiograph showed an area in the periumbilical region and left flank comprising nodular and curvilinear soft tissue densities (Figure 1). In the context of vomiting worms, these densities were interpreted as a mass of worms within bowel loops. The radiograph did not show evidence of bowel obstruction. Given the patient's elevated liver enzymes, abdominal ultrasonography was performed, which showed echogenic portal triads, multiple tortuous tubular structures in the gall bladder and dilated biliary tree, consistent with biliary ascariasis (Figure 2). The echogenic portal triads would also have been consistent with infectious cholangitis, but the patient's clinical presentation did not suggest this diagnosis. No hepatic abscess was seen. A vomited worm, submitted to the laboratory for identification, confirmed infestation with Ascaris spp. (Figure 3). Stool tested for ova and parasites confirmed presence of Ascaris eggs, and no other intestinal parasites were detected.
The patient was transferred to a tertiary pediatric referral centre, and the infectious diseases and gastroenterology teams were consulted. He remained afebrile, appeared well and had no clinical evidence of bowel obstruction. We treated him with oral mebendazole (100 mg by mouth, twice daily). He continued to pass worms per rectum and did not have further emesis during this course of therapy. We considered endoscopic retrograde cholangiopancreatography (ERCP) to remove the Ascaris directly, but medical therapy was preferred owing to the patient's clinical stability and the technical challenges of performing ERCP in a young child.
After 3 days of treatment with oral mebendazole, repeat abdominal ultrasonography showed reduced burden of Ascaris in the biliary system, although some worms remained. On the presumption that these worms would continue to exit the biliary system and enter the gastrointestinal tract, where they would be amenable to treatment with mebendazole, the course was extended an additional 3 days. After 6 days of treatment, repeat abdominal ultrasonography showed clearance of Ascaris from the biliary system with some residual mild dilatation of the bile ducts. After the extended treatment, the patient continued to pass worms per rectum but in decreasing numbers, with normal stools in between. His transaminase and lipase levels decreased and his oral intake improved.
While in hospital, the patient had a karyotype test, which confirmed a diagnosis of trisomy 21. He had health supervision screening for trisomy 21, which identified primary hypothyroidism, and he was started on levothyroxine....