Correction: Effect of probiotic treatment on the clinical course, intestinal microbiome, and toxigenic Clostridium perfringens in dogs with acute hemorrhagic diarrhea.

[This corrects the article DOI: 10.1371/journal.pone.0204691.].

Prevalence of Clostridium perfringens netE and netF toxin genes in the feces of dogs with acute hemorrhagic diarrhea syndrome.

BACKGROUND: Recently, novel pore-forming toxin genes designated netE and netF were identified in a Clostridium perfringens type A strain isolated from a dog with acute hemorrhagic diarrhea. OBJECTIVES: Pore-forming toxins could play an important role in the disease pattern of acute hemorrhagic diarrhea syndrome (AHDS) in dogs. Thus, we aimed to determine the prevalence of C. perfringens genes encoding for netE and netF in the feces of dogs with AHDS and to evaluate any association between selected clinical variables and the presence of these toxin genes. ANIMALS: In total, 174 dogs were included in the study. METHODS: Fecal samples of all dogs were tested by real-time polymerase chain reaction for netE and netF genes. Time to recovery, hospitalization time, and selected laboratory variables were compared between dogs with AHDS that were positive or negative for the toxin genes. RESULTS: A significant difference was found among the 3 groups in the prevalence of the pore-forming toxin genes netE and netF: dogs with AHDS: 26 of 54 (48.1%); dogs with canine parvovirus (CPV) infection: 0 of 54 (0%); and healthy dogs: 8 of 66 (12.1%; P < .001). In dogs with AHDS, no significant difference was detected in any variables evaluated between netE-positive and netF-positive and netE-negative and netF-negative dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The prevalence of C. perfringens encoding for netE and netF is significantly higher in dogs with AHDS compared to control dogs. Further studies are warranted to evaluate whether these toxins are an inciting cause for AHDS in dogs.

Effect of probiotic treatment on the clinical course, intestinal microbiome, and toxigenic Clostridium perfringens in dogs with acute hemorrhagic diarrhea.

INTRODUCTION: The impact of probiotics on dogs with acute hemorrhagic diarrhea syndrome (AHDS) has not been evaluated so far. The study aim was to assess the effect of probiotic treatment on the clinical course, intestinal microbiome, and toxigenic Clostridium perfringens in dogs with AHDS in a prospective, placebo-controlled, blinded trial. METHODS: Twenty-five dogs with AHDS with no signs of sepsis were randomly divided into a probiotic (PRO; Visbiome, ExeGi Pharma) and placebo group (PLAC). Treatment was administered for 21 days without antibiotics. Clinical signs were evaluated daily from day 0 to day 8. Key bacterial taxa, C. perfringens encoding NetF toxin and enterotoxin were assessed on days 0, 7, 21. RESULTS: Both groups showed a rapid clinical improvement. In PRO a significant clinical recovery was observed on day 3 (p = 0.008), while in PLAC it was observed on day 4 (p = 0.002) compared to day 0. Abundance of Blautia (p<0.001) and Faecalibacterium (p = 0.035) was significantly higher in PRO on day 7 compared to day 0, while in PLAC the abundance of Faecalibacterium was not significantly higher on any study day and Blautia (p = 0.016) was only significantly higher on day 21 compared to day 0. Abundance of C. perfringens was significantly lower on day 7 (p = 0.011) compared to day 0 in PRO but not in PLAC. Enterotoxin genes were significantly lower in PRO on day 21 (p = 0.028) compared to PLAC. Fecal samples of 57% of all dogs were positive for netF toxin genes on day 0 and the abundance was significantly lower on day 7 compared to day 0 in PRO (p = 0.016) and PLAC (p = 0.031). CONCLUSION: The probiotic treatment was associated with an accelerated normalization of the intestinal microbiome. Dogs with aseptic AHDS showed a rapid decrease of netF toxin genes and fast clinical recovery in both groups under symptomatic treatment without antibiotics.