Pear-shaped worm disease (giardiasis) is caused by Giardia lamblia. The pear-shaped flagellate mainly parasitizes the small intestine and gallbladder. The main clinical manifestation is diarrhea. When the pathogen parasitizes the bile duct, it can cause cholecystitis or cholangitis, with a higher incidence in children. In recent years, the incidence rate has sharply increased in many countries and has been listed as one of the causes of traveler's diarrhea.

bubble_chart Clinical Manifestations

The main symptoms are gastrointestinal, including diarrhea with loose, frothy, or mucous stools, large amounts of grayish-white, foul-smelling feces, abdominal pain, anorexia, lack of strength, anemia, and weight loss. A few patients may experience tenderness in the liver and gallbladder area, grade I hepatomegaly, and abnormal liver function. For cases of unexplained diarrhea, abdominal pain, lack of strength, malabsorption syndrome, or chronic biliary inflammation, this disease should be considered.

bubble_chart Auxiliary Examination

1. Stool Examination During the acute phase, loose stools can be directly smeared and examined under a microscope to identify pear-shaped trophozoites. Staining with Giemsa or hematoxylin can improve the positive detection rate. The zinc sulfate flotation and sedimentation method yields better results. If necessary, stool samples can be preserved in formaldehyde solution or polyvinyl alcohol for further examination. In formed stools, pear-shaped cysts can be detected. After dilution with saline, smears can be prepared using 1% potassium iodide or stained with hematoxylin. Repeated examinations can enhance the positive detection rate.
2. Duodenal drainage fluid can be examined for trophozoites, or the nylon string capsule method may be used (a 26mm x 6mm capsule containing a silicone-coated lead ball is connected to a nylon string, which the child swallows; the capsule passes through the stomach and pylorus into the duodenum, with the other end of the string fixed to the child's cheek. After 4 hours, the nylon string and capsule are retrieved, and the adherent intestinal secretions on the string are scraped off for examination) to detect pathogens. (3) Diagnostic Therapeutic Trial A rapid response to metronidazole trial treatment can confirm the diagnosis of this disease.

bubble_chart Treatment Measures

﹝Treatment﹞

(1) Metronidazole dose is 15-20mg/kg per day, divided into 3 doses, with a 7-day course of treatment. (2) Chloroquine dose is 7mg/kg per day, divided into 3 doses, with a 5-day course of treatment. (3) Furazolidone dose is 5-10mg/kg per day, divided into 3-4 doses, with a 7-day course of treatment. (4) Atabrine is easily absorbed orally and excreted through the biliary tract. The dose is 8mg/(kg·d), divided into 3 doses, taken continuously for 5 days, with a cure rate of over 90%. Side effects include nausea, vomiting, and skin yellowing.

bubble_chart Prevention

(1) Thoroughly treat acute and chronic patients. (2) Pay attention to personal hygiene, food hygiene, and environmental sanitation.