Strongyloides IgG ELISA Kit

Strongyloides stercoralis is a type of roundworm that causes strongyloidiasis, which is capable of causing chronic infections and may lead to outbreaks of life-threatening, highly infectious strongyloidiasis in the event of immune system problems. It is endemic worldwide and is most prevalent in tropical and subtropical regions. A number of diseases and behaviors that interfere with the proper functioning of the immune system increase the risk of developing strongyloidiasis, including HIV infection, hypogammaglobulinemia, alcohol abuse, and malnutrition. The epidemiology of S. stercoralis differs from other helminthic infections in its unique ability to reinfect humans.

S. stercoralis usually infects humans through the skin. When a person steps barefoot on contaminated soil, the filamentous larvae can penetrate the skin of the foot. Some primary infections can also occur through consumption of contaminated food or water. After entering the human body, the filamentous larvae migrate to the lungs and mature, then stimulate coughing and are swallowed into the digestive system. The larvae mature into adult females in the small intestine and lay eggs intermittently through asexual reproduction. These eggs hatch into rhabditiform larvae and are excreted in the feces. Rhabditiform larvae can produce infectious filamentous larvae in the soil or the host intestine, and filamentous larvae produced in the host can invade the intestinal mucosa or perianal skin, restart the infection cycle, resulting in long-term subclinical infection in patients. The expelled rhabditiform larvae can continue to grow into adults in the soil, and the female and male adults will mate, and the female adult insects will lay eggs in the soil. The eggs hatch into rhabditiform larvae and develop into infectious filamentous larvae.

Figure 1. Life cycle of Strongyloides stercorali
(Source: Luvira V, et al. 2022)

Patients with unexplained eosinophilia need to be considered in conjunction with epidemiologic investigations for the presence of strongyloidiasis. Parasitological and serologic tests are usually used to determine the presence of S. stercoralis infection, and the direct observation of larvae is the gold standard for the diagnosis of strongyloidiasis, however, the sensitivity of fecal microscopy of a single specimen is too low, and it can be improved by repeating the test on multiple samples. PCR has been used for the diagnosis of strongyloidiasis, but the method varies widely in sensitivity and nucleic acid probes are not readily available. The negative predictive value of serologic testing for immigrants in low-incidence settings is close to 100%, unlike testing for recent infections, which has a negative predictive value of only 72%. Because of the limitations of existing parasitological and serologic diagnostic methods, clinicians often recommend several approaches to synthesize the presence of a parasitic infection.

Strongyloides stercoralis IgG ELISA Kit
S. stercoralis IgG ELISA Kit