USAID's NTD Program

Roundworm: Ascariasis

Diagnosis

Diagnosis requires careful examination under a microscope of a fecal sample for eggs.
Common methods for eggs search and count include the direct examination of stool mixture with 0.85 percent NaCl and the Kato-Katz.¹

Stool samples for eggs might be negative in the case of pneumonitis from A. lumbricoides in a newly infected individual. Chest radiographs usually reveal infiltrates and examination of sputum could reveal Charcot-Leyden crystals.

Ultrasonography and radiology are the most appropriate tools to diagnose of intestinal and biliary obstruction due to A. lumbricoides as well as to detect other abdominal localization of the worms.²

Learn more about roundworm:

• Epidemiology
• Symptoms
• Life Cycle
• Treatment, Prevention, and Control
• Back to Roundworm Overview

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References

1. World Health Organization: Prevention and control of schistosomiasis and soil transmitted helminthiasis. Report of a WHO expert committee, WHO Technical Report Series 912. Geneva, World Health Organization, 2002.
2. Ferreyra NP, Cerri GG: Ascariasis of the alimentary tract, liver, pancreas and biliary system: Its diagnosis by ultrasonography. Hepatogastroenterology. 45:932, 1998.