Treatment of strongyloidiasis in HTLV-1 and Strongyloides stercoralis coinfected patients is associated with increased TNFα and decreased soluble IL2 receptor levels

Abstract

Background: Human T cell lymphotropic virus type 1 (HTLV-1) infection has been associated with recurrent and disseminated strongyloidiasis and adult T cell leukemia/lymphoma (ATLL). Methods:We compared immunological aspects and markers for ATLL in HTLV-1 patients with or without strongyloidiasis, and evaluated the influence of Strongyloides stercoralis treatment on the immune response and clinical outcomes of HTLV-1 infection.Results: Levels of TNFa and IFNg were lower in patients coinfected with HTLV-1 and S. stercoralis than in patients with HTLV-1 only (p , 0.05), and there was an increase in TNFa levels after anthelmintic treatment. Levels of sIL-2R were higher in patients with HTLV-1 coinfected with S. stercoralis and anthelmintic treatment decreased sIL-2R levels (p , 0.05). The one patient who developed ATLL was coinfected with S. stercoralis. Conclusion:These data show that helminthic infection has a modulatory role in HTLV-1 infection and that S. stercoralis may be a cofactor in the development of ATLL.

The Influence of Human T-Lymphotropic Virus 1 on Patients Coinfected by the Helminth Strongyloides stercoralis

“…coinfected with S. stercoralis and HTLV-1, not present haematological alterations, however, we verified the existence of reports of cases that evaluated this association [4,27]. As under normal circumstances the response against parasitic infections is of the Th2 type, the negative regulation of the anti-inflammatory response in patients coinfected with S. stercoralis and HTLV-1 facilitates disseminated strongyloidiasis [10,17]. On the other hand, the negative regulation of IL-4 in individuals coinfected with S. stercoralis and HTLV-1 can cause deficient IgE responses which are important in controlling this parasite.…”

“…Additionally, it was ascertained that after treatment for strongyloidiasis, the levels of TNF-α increased when compared with levels prior to treatment, indicating that strongyloidiasis exercises an important immunomodulatory role in the host, in some manner facilitating viral replication. Regarding the levels of IL-5 and IL-10, significant statistical differences were not found between the groups with and without coinfection, before or after treatment for strongyloidiasis [17]. In contrast, Porto, et al [26], reported that the frequency of interleukin 10 (IL-10)-secreting CD8+ T cells is higher in patients carrying HTLV-1 who are coinfected with S. stercoralis, when compared with HTLV-1 positive patients who are not coinfected.…”

“…Strongyloidiasis generally promotes chronic and asymptomatic infections in immunocompetent individuals, whose effector mechanisms of immune cells impede the parasite's dissemination in the intestine. In immunocompromised individuals, however, the number of parasites is found to be high, which may cause hyperinfection or disseminated infection, sometimes resulting in death [1,4,17].…”

“…Acting in both directions, strongyloidiasis seems to facilitate the replication of the HTLV-1 virus and shorten the latency period, as -subsequent to the use of antiparasitic agents -reduction in the levels of the virus's mRNA, and an increase in tumor necrosis factor alpha (TNF-α) and IFN-γ were evidenced [17,32,33]. Levels of IFN-γ and TNF-α are higher in patients infected only with HTLV-1 than among those coinfected with S. stercoralis, as ascertained in a study with 60 patients in Bahia, which compared certain immunological aspects of patients with HTLV-1 who were or were not coinfected with S. stercoralis, before and after treatment.…”

Strongyloidiasis in Solid Organ Transplantation

“…Recurrent asthma, especially if induced or exacerbated by corticosteroids, has also been attributed to, and should heighten suspicion for, chronic S. stercoralis infection [35,56]. It has been proposed that chronic strongyloidiasis can increase the risk of adult T-cell leukemia/lymphoma in patients with HTLV-I [57].…”