ABSTRACT
Abstract | Bacillus clausii is a gram-positive rod used as a probiotic to treat diarrhea and the side effects of antibiotics such as pseudomembranous colitis. We report a case of B. clausii bacteremia in a non-immunocompromised patient with active peptic ulcer disease and acute diarrhea. The probiotic was administered during the patient's hospitalization due to diarrhea of infectious origin. B. clausii was identified in the bloodstream of the patient through Matrix- Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) days after her discharge. Given the wide use of probiotics, we alert clinicians to consider this microorganism as a causative agent when signs of systemic infection, metabolic compromise, and hemodynamic instability establish after its administration and no pathogens have been identified that could explain the clinical course.
Resumen | Bacillus clausii es un bacilo Gram positivo usado como probiótico para tratar la diarrea y efectos adversos de los antibióticos, como la colitis pseudomembranosa. Se reporta un caso de bacteriemia por B. clausii en una paciente inmunocompetente con enfermedad ulcerosa péptica activa y diarrea aguda. El probiótico le fue administrado durante la hospitalización debido al origen infeccioso de la diarrea. B. clausii se identificó en el torrente sanguíneo de la paciente, utilizando espectrometría de desorción/ionización mediante láser asistido por matriz (Matrix-Assisted Laser Desorption/Ionization, MALDI), acoplada a un detector de iones (Time of Flight, TOF) (MALDI-TOF), días después de haber sido dada de alta. Dado el amplio uso de los probióticos, alertamos a los clínicos para que consideren este microorganismo como agente causal cuando se detecten signos de infección sistémica, compromiso metabólico, e inestabilidad hemodinámica tras su administración, y no se haya identificado ningún patógeno que pueda explicar el cuadro clínico.
Subject(s)
Bacteremia , Bacillus clausii , Probiotics , Diarrhea , Gram-Positive BacteriaABSTRACT
OBJECTIVE: The study aimed to determine the basic histomorphologic effects of Bacillus clausii (B. clausii) spores in enteropathogenic Escherichia coli (E. coli) O127:H21-infected mice by evaluating the spleen, mesenteric lymph nodes, and intestinal mucosa. METHODS: The study involved 46 apparently healthy Balb/c mice (Mus musculus) which were acclimatized for 19 days prior to any intervention. Sixteen mice were used to determine the sublethal dose of E. coli, which was performed by administering serially-diluted solutions and subsequent generation of a standard curve. From the remaining 30 mice, ten served as normal controls while the remaining 20 were randomized to receive either B. clausii or placebo of sterile water for a week. All mice were then challenged with E. coli for another week and euthanized, and the spleen, mesenteric lymph nodes, and small intestine harvested and examined microscopically. All study personnel were blinded of the treatment assignments. RESULTS: Histologic evaluation of the small intestine in E. coli only-fed mice exhibited prominent attachment effacement lesions, with severely denuded mucosa, lymphocytic infiltration, and debris in the intestinal lumen. However, mice given B. clausii prior to E. coli infection displayed only minimal mucosal damage with less sloughing of villus tips, plus increased mucus-secreting goblet cells. In the spleen, E. coli only-fed mice showed moderate to severe lymphoid hyperplasia with blurred boundaries between red and white pulp. In contrast, mice which received B. clausii prior to E. coli infection had only mild degrees of lymphoid hyperplasia. Similar findings were seen in the mesenteric lymph nodes where E. coli only-fed mice showed moderate to severe lymphoid hyperplasia while those given B. clausii prior to E. coli infection merely had mild lymphoid hyperplasia. CONCLUSION: B. clausii exerts a potential protective and immunomodulatory action in E. coli O127:H21-infected mice based on histomorphologic effects. However, additional studies are needed to fully characterize these mechanisms.mice based on histomorphologic effects.