Luminal anisakiasis is easily diagnosed when a nematode is extracted from a patient, either by coughing or by the crawling of the larvae from the patient's anus. This diagnosis is confirmed if the patient has a history of eating raw fish.

Diagnosis of acute gastric anisakiasis is obtained by endoscopy and the removal of the larvae with forceps.

The radioallergosorbent test (RAST) has been in recent development, and tests for IgE and IgG antibodies in the serum of potential patients, using antigens prepared from larval stage Anisakis simplex. If the serum is RAST-positive for the A. simplex antigen, then the diagnosis is confirmed. However, a potential drawback to such a serologic test is its nonspecificity due to cross-reactions between various helminths.

Section of Anisakis in the ileum of a Japanese patient.

 

Link to Case Study #4 and #5