The Importance of Screening Strongyloides stercoralis Infection in Solid Organ Transplant Donors and Recipients

Strongyloides stercoralis is an intestinal nematode with worldwide distribution which is endemic in tropical and subtropical areas. It is unique in its ability to complete its entire life cycle and reinfect its human host via a phenomenon called autoinfection. The majority of infections are clinically asymptomatic or can manifest with gastrointestinal symptoms, such as heartburn, bloating, diarrhea, abdominal discomfort, gastroesophageal reflux disease (GERD), or symptoms related to the penetration of larvae through skin, including dermatitis and eosinophilia. Immunosuppressed patients, such as solid organ transplant patients with untreated strongyloidiasis are at great risk of hyperinfection, dissemination syndromes, and often fatal conditions associated with strongyloidiasis.

In this retrospective single-center cross-sectional study, we evaluated 157 cases (131 heart, lung, and kidney transplant recipients and 26 kidney donors) in Tehran, Iran, from March 2020 to April 2021. Demographic information including age, gender, place of birth, place of residence, underlying disease, being the donor or recipient, history of previous transplant and type of transplant, travel history to endemic regions, and seropositivity for S. stercoralis were evaluated.

Among 157 cases with a mean age of 38.9 years, 40 (25.5%) cases tested positive for S. stercoralis antibodies. Out of 26 donors, eight cases were seropositive, and among 131 recipients, 32 cases were seropositive. There was no significant correlation between birth place and place of residence in endemic areas and seropositivity for S. stercoralis. None of the cases showed hypereosinophilia, hyperinfection, or disseminated syndrome. Also, we found no significant correlation between the type and time of transplant, history of previous transplants, and S. stercoralis infection.

Universal screening for S. stercoralis latent infection is important in immunosuppressed patients, especially in solid organ transplants because of the high risk of hyperinfection and disseminated syndrome, which may culminate in death. Furthermore, screening for latent strongyloides infection in donors seems to be necessary because of the possibility of strongyloides infection being transmitted from donors to recipients.