David Ruiz-Raga

Strongyloidiasis is traditionally regarded as a tropical disease; however, in the Valencian Community (Spain), it has historically been linked to localized endemic foci considered of declining relevance. This was a multicenter regional case series study across three hospitals including patients ≥16 years with strongyloidiasis defined by positive serology and/or parasitological confirmation diagnosed from 2015 to 2024. A total of 301 patients were included (median age 53 years (quartile 1–quartile 3, 40–72); 135 (44.9%) female). Most cases were autochthonous (176/299, 58.9%), while 123/299 (41.1%) occurred in migrants, predominantly from Latin America. Symptoms were present in 165/296 (55.7%), most frequently cutaneous (68/296, 23.0%) and gastrointestinal (62/296, 20.9%). Eosinophilia (>500 cells/µL) was observed in 144/298 (48.3%) and severe infection (hyperinfection syndrome) in 7/294 (2.4%). Annual diagnoses increased over time, with a significant temporal trend by case origin (p < 0.001), reflecting an increasing contribution of imported infections, whereas trends by sex (p = 0.068) and immune status (p = 0.926) were not significant. Stool-based methods demonstrated a low diagnostic yield (microscopy 7/157, 4.5%; culture 21/136, 15.4%; rtPCR 2/27, 7.4%). These findings document the sustained detection of cases classified as autochthonous beyond historically recognized foci and an increasing proportion of imported diagnoses in a temperate European setting.

Background: Clostridioides difficile infection (CDI) is the leading cause of nosocomial diarrhea. Current diagnostic tools have difficulty distinguishing between colonization and active infection. This study evaluated the utility of fecal metabolomics in diagnosing CDI in hospitalized patients with acute diarrhea. Methods: We conducted a prospective observational study involving hospitalized adults with new-onset diarrhea during admission. Participants were stratified into groups based on clinical and microbiological findings: controls, C. difficile colonized and C. difficile infected. Fecal samples were analyzed using UPLC-MS/MS and GC-MS to quantify selected short-chain fatty acids, amino acids, and bile acids. Multivariate and univariate statistical analyses included PLS-DA, sPLSDA, and tests with FDR correction. Results: Infected patients exhibited significantly higher concentrations of SCFAs and notable alterations in bile acid profiles. Key discriminative metabolites included isovalerate, propionate, isobutyrate and alpha-aminobutyric acid. ROC curve analyses showed strong diagnostic performance for these markers, with AUC values exceeding 0.85. Conclusions: Fecal metabolomic profiling could effectively differentiate between colonization and infection in CDI among hospitalized patients with diarrhea. These results highlight the potential of metabolomic signatures to enhance the diagnostic precision for CDI.

Clostridioides difficile infection (CDI) is the leading cause of nosocomial diarrhea. Current diagnostic tools have difficulty distinguishing between colonization and active infection. This study evaluated the utility of fecal metabolomics in diagnosing CDI in hospitalized patients with acute diarrhea. We conducted a prospective observational study involving hospitalized adults with new-onset diarrhea during admission. Participants were strati-fied into groups based on clinical and microbiological findings: controls, C. difficile col-onized and C. difficile infected. Fecal samples were analyzed using UPLC-MS/MS and GC-MS to quantify selected short-chain fatty acids, amino acids, and bile acids. Multi-variate and univariate statistical analyses included PLS-DA, sPLSDA, and tests with FDR correction. Infected patients exhibited significantly higher concentrations of SCFAs and notable alterations in bile acid profiles. Key discriminative metabolites included isova-lerate, propionate, isobutyrate and alpha-aminobutyric acid. ROC curve analyses showed strong diagnostic performance for these markers, with AUC values exceeding 0.85. Fecal metabolomic profiling could effectively differentiate between colonization and infection in CDI among hospitalized patients with diarrhea. These results highlight the potential of metabolomic signatures to enhance the diagnostic precision for CDI.