Ascariasis Treatment & Management

Updated: Apr 15, 2016
  • Author: David R Haburchak, MD, FACP; Chief Editor: Pranatharthi Haran Chandrasekar, MBBS, MD  more...
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Medical Care

Because of the risk of complications, patients with ascariasis who have other concomitant helminthic infections should always undergo treatment for ascariasis first. Medical therapy is usually not indicated during active pulmonary infection because dying larvae are considered a higher risk for significant pneumonitis. Pulmonary symptoms may be ameliorated with inhaled bronchodilator therapy or corticosteroids, if necessary.

Albendazole 400 mg one dose orally is the drug of choice. A 2012 study from Indonesia showed that albendazole provided statistically significant better sterilization of Ascaris eggs than mebendazole but equivalent cure rates and egg reduction rates. [22] Ascariasis commonly coexists with whipworm infection, which appears to be most susceptible to triple-dose mebendazole. [23] Albendazole is not recommended during pregnancy; pyrantel pamoate is the drug of choice in these cases.

Alternative therapy is mebendazole (100 mg bid for 3 d or 500 mg as a single dose). Mebendazole is not recommended during pregnancy; pyrantel pamoate is the drug of choice in these cases.

Paralyzing vermifuges (eg, pyrantel pamoate, piperazine, ivermectin) should be avoided in patients with complete or partial intestinal obstruction since the paralyzed worms may necessitate or further complicate surgery.

Vitamin A supplementation improved growth development of children in Zaire; deworming did not improve growth development in this study. [24]

Drug therapy affects only adult worms. If the patient lives in an endemic area or has recently relocated, he or she may still be carrying larvae that are not yet susceptible. Such patients should be re-evaluated in 3 months and retreated if stool ova persist. In endemic areas, reinfection rates approach 80% within 6 months.

Nitazoxanide, a drug used primarily for protozoal infection, was shown to have 89% clinical efficacy for the treatment of ascariasis in rural Mexico and may offer a future alternative to other medications. [25]


Surgical Care

Conservative management of partial intestinal obstruction and biliary ascariasis is usually effective. The patient is maintained on nothing-by-mouth status, and the partial obstruction usually spontaneously resolves. Preventing oral intake decreases the risk of food compounding the obstruction while normal peristalsis redistributes or evacuates the worms. A controlled trial from Pakistan found that, in patients without peritonitis, hypertonic saline enemas relieved obstruction more quickly (1.6 d vs 3.4 d) and resulted in shorter hospital stays (4 d vs 6 d) than intravenous fluids alone. A recent study from India demonstrated that conservative therapy was successful in 19 of 22 (89%) children with intestinal obstruction. The regimen used consisted of no oral intake, intravenous fluids, antibiotics, piperazine salt per nasogastric tube, and glycerine plus liquid paraffin emulsion enemas. [16]

Recommended criteria for surgical exploration include the following:

  • Passage of blood per rectum
  • Multiple air fluid levels on abdominal radiographs
  • An ill child with abdominal distension and rebound tenderness
  • Unsatisfactory response to conservative therapy
  • Appendicitis and primary peritonitis
  • Hepatobiliary disease
  • Pancreatic pseudocyst

Most (49-90%) worms eventually migrate from the biliary system spontaneously. Drug therapy should be delayed in patients with right upper quadrant or pancreatic pain, as no evidence has shown that drugs are active against worms located in the biliary tree. Regardless, death of the worm in the duct may provoke both inflammation and obstruction. Patients with ascariasis who have only minor symptoms can undergo observation for 3 days. If the minor symptoms persist after 3 days or the patient develops frank cholangitis or pancreatitis, removal of the worms with ERCP should be attempted, if available. Although technically challenging at times, ERCP extraction rates have exceeded 90%. [19]

Intestinal or biliary surgery may be necessary for complications of ascariasis.

Intestinal gangrene usually occurs at the terminal ileum, more often after the use of pyrantel pamoate, which tetanically paralyzes worms and thereby enhances the risk of obstruction. Recently, 2 cases of delayed distal intestinal disease have been reported, which were thought to be secondary to toxins from the worms. Therefore, patients should probably be monitored for some time after the surgical removal of worms.

Milking of worms to the large bowel, resection of gangrenous bowel, ileostomy, and enterotomy are the most common surgical procedures used to manage bowel obstruction.

Invasion of the gall bladder necessitates cholecystectomy, common duct exploration, and T-tube drainage until the patient is stabilized and dewormed.

Any patients from highly endemic areas should be screened, and if positive, treated for ascariasis and malnutrion prior to elective surgery because of possible provocation of worm migration with anesthesia agents. [26] In particular, patients who live in endemic areas should be dewormed before and after elective cholecystectomy.