Strongyloides stercoralis infection induces gut dysbiosis in chronic kidney disease patients
Authors: Hai Nguyen Thi , Hongsrichan Nuttanan , Intuyod Kitti , Pinlaor Porntip , Yingklang Manachai , Chaidee Apisit , Pongking Thatsanapong , Anutrakulchai Sirirat , Cha’on Ubon , Pinlaor Somchai 
Published: March 2022

AbstractBackgroundStrongyloides stercoralis infection typically causes severe symptoms in immunocompromised patients. However, the progression of infection-driven chronic kidney disease (CKD) is not understood fully. Recent studies have shown that gut dysbiosis plays an important role in the progression of CKD. Hence, this study aims to investigate the effect of S. stercoralis infection on the gut microbiome in CKD patients.Methodology/Principal FindingsAmong 838 volunteers from Khon Kaen Province, northeastern Thailand, 40 subjects with CKD were enrolled and divided into two groups (S. stercoralis-infected and -uninfected) matched for age, sex and biochemical parameters. Next-generation technology was used to amplify and sequence the V3-V4 region of the 16S rRNA gene to provide a profile of the gut microbiota. Results revealed that members of the S. stercoralis-infected group had lower gut microbial diversity than was seen in the uninfected group. Interestingly, there was significantly greater representation of some pathogenic bacteria in the S. stercoralis-infected CKD group, including Escherichia-Shigella (P = 0.013), Rothia (P = 0.013) and Aggregatibacter (P = 0.03). There was also a trend towards increased Actinomyces, Streptococcus and Haemophilus (P > 0.05) in this group. On the other hand, the S. stercoralis-infected CKD group had significantly lower representation of SCFA-producing bacteria such as Anaerostipes (P = 0.01), Coprococcus_1 (0.043) and a non-significant decrease of Akkermansia, Eubacterium rectale and Eubacterium hallii (P > 0.05) relative to the uninfected group. Interesting, the genera Escherichia-Shigella and Anaerostipes exhibited opposing trends, which were significantly related to sex, age, infection status and CKD stages. The genus Escherichia-Shigella was significantly more abundant in CKD patients over the age of 65 years and infected with S. stercoralis. A correlation analysis showed inverse moderate correlation between the abundance of the genus of Escherichia-Shigella and the level of estimated glomerular filtration rate (eGFR).Conclusions/SignificanceConclusion, the results suggest that S. stercoralis infection induced gut dysbiosis in the CKD patients, which might be involved in CKD progression.Author summaryHuman strongyloidiasis is caused by a soil-transmitted helminth, Strongyloides stercoralis, which typically causes severe symptoms in immunocompromised. However the relationship between S. stercoralis and chronic kidney disease patients (CKD) progression was not known. This is the first study to investigate the gut microbiota of CKD patients with and without S. stercoralis using high-throughput sequencing of the V3–V4 region of the 16S rRNA gene. Infection with S. stercoralis was associated with reduced gut microbiota diversity than in the uninfected group. In addition, infection with this nematode led to reduced abundance of SCFA-producing bacteria and enrichment of pathogenic bacteria. In particular, there were significant differences in abundance of the beneficial genus Anaerostipes (a decrease) and the pathogenic taxon Escherichia-Shigella (an increase) in CKD patients infected with S. stercoralis relative to controls. In the infected group, the representation of genus Escherichia-Shigella was significant higher in patients over the age of 65 years. There was a significant inverse moderate correlation of Escherichia-Shigella with the estimated glomerular filtration rate (eGFR).