Serodiagnosis of ascariasis with specific IgG4 antibody and its use in an epidemiological study

Abstract

In an earlier study Ascaris-specific IgG4 antibody was found to be elevated in cases of ascariasis. However, the usefulness of the elevated levels of this antibody in Ascaris infection as a diagnostic marker has not been well established. In India, in early 1999, blood samples of 83 cases of Ascaris infection, 35 cases of other nematode infection and 53 control subjects (without any helminth infection) were tested for anti-Ascaris IgG4 by ELISA. Further anti-Ascaris IgG4 levels in the blood of Ascaris-infected patients were determined, after eradication of the worms with drugs, at regular intervals to ascertain the duration of elevation of titre of the serological marker following initial infection. This information would indicate the sensitivity of the test as a diagnostic marker for recent infection. Blood samples of 422 rural people were also tested for anti-Ascaris IgG4 titre to ascertain the prevalence of ascariasis in the community. High levels of anti-Ascaris IgG4 antibody (OD 1.246 +/- 0.212) were found in all the 83 Ascaris-infected subjects compared to controls (OD 0.158 +/- 0.047). Anti-Ascaris IgG4 antibody levels of other nematode-infected subjects were comparable to the controls. Anthelmintic treatment of 8 Ascaris-infected subjects caused sequential fall of IgG4 level in their blood, and its titre reached control level within 6 months of deworming. Of 422 individuals from the rural community 229 (54.3%) had significantly high levels of specific IgG4 antibody against Ascaris excretory-secretory antigen, suggesting that they were infested with Ascaris. Thus, this study demonstrated that anti-Ascaris IgG4 antibody is a very sensitive and specific marker for the diagnosis of Ascaris infection. Utilizing this test, a significant number of a rural population could be diagnosed with Ascaris infection in West Bengal, India.

Serological diagnosis of clonorchiasis: using a recombinant propeptide of cathepsin L proteinase from Clonorchis sinensis as a candidate antigen

“…Prominent increase of IgG4 antibodies in serum takes place in several kinds of human helminthiases, such as schistosomiasis (Naus et al 2003), ascariasis (Santra et al 2001), hydatid disease (Aceti et al 1993), and cysticercosis (Huang et al 2002). IgG is the major responding antibody type in sera from clonorchiasis patients (Lin et al 1995;Yen et al 1992).…”

“…In addition, IgG4 is a shortrange antibody. Its level will reduce significantly within 6 months of deworming (Hong 1988;Santra et al 2001) so that anti-C. sinensis IgG4 antibody detection in sera from clonorchiasis patients with CsCatL-propeptide using ELISA can be used for serodiagnosis of clonorchiasis, based on the degree of infection and valuation of therapeutic effect.…”

Parasitic Pneumonia and Lung Involvement

“…Ascaris lumbricoides can produce both specific and polyclonal IgE [138]. Elevation of IgG4 levels in patients with Ascariasis has also been reported [139]. Symptomatic pulmonary involvement may range from mild cough to a Loffler's syndrome which is a self-limiting lung inflammation and is associated with blood and pulmonary eosinophilia, particularly childhood Ascariasis [3, 140].…”

Influence of Human Leukocyte Antigen on Susceptibility of Tropical Pulmonary Infectious Diseases and Clinical Implications

“…Ascaris lumbricoides can produces both specific and polyclonal IgE [85]. Elevation of IgG4 levels in patients with ascariasis have also been reported [86]. Symptomatic pulmonary involvement may range from mild cough to a Lof-fler's syndrome which is a self-limiting lung inflammation and is associated with blood and pulmonary eosinophilia, particularly childhood ascariasis [87,88].…”