Post-splenectomy infections in chronic schistosomiasis as a consequence of bacterial translocation

• Published in: Revista da Sociedade Brasileira de Medicina Tropical Vol. 48; no. 3; pp. 314 - 320
• Main Authors: Lima, Kedma de Magalhães, Negro-Dellacqua, Melissa, Dos Santos, Victor Emmanuell Fernandes Apolônio, de Castro, Célia Maria Machado Barbosa
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Medicina Tropical - SBMT 01-06-2015; Sociedade Brasileira de Medicina Tropical (SBMT)
• Subjects: Animals; Bacterial translocation; Bacterial Translocation - physiology; Chronic Disease; Disease Models, Animal; Female; Intestinal morphometry; Intestinal Mucosa - microbiology; Mesenteric lymph nodes; Mice; Parasite Egg Count; Parasite Load; Schistosoma mansoni; Schistosomiasis; Schistosomiasis mansoni - microbiology; Schistosomiasis mansoni - physiopathology; Splenectomy; Time Factors; TROPICAL MEDICINE; Splenectomy; Schistosomiasis; Intestinal morphometry; Mesenteric lymph nodes; Bacterial translocation
• ISSN: 0037-8682; 1678-9849; 1678-9849; 0037-8682
• DOI: 10.1590/0037-8682-0042-2015

Bacterial translocation is the invasion of indigenous intestinal bacteria through the gut mucosa to normally sterile tissues and internal organs. Schistosomiasis may cause alterations in the immune system and damage to the intestines, portal system and mesenteric lymph nodes. This study investigated bacterial translocation and alterations in the intestinal microbiota and mucosa in schistosomiasis and splenectomized mice.
Forty female 35-day-old Swiss Webster mice were divided into the following four groups with 10 animals each: schistosomotic (ESF), splenectomized schistosomotic (ESEF), splenectomized (EF) and control (CF). Infection was achieved by introduction of 50 Schistosoma mansoni (SLM) cercariae through the skin. At 125 days after birth, half of the parasitized and unparasitized mice were subjected to splenectomy. Body weights were recorded for one week after splenectomy; then, the mice were euthanized to study bacterial translocation, microbiota composition and intestinal morphometry.
We observed significant reductions in the weight increases in the EF, ESF and ESEF groups. There were increases of at least 1,000 CFU of intestinal microbiota bacteria in these groups compared with the CF. The EF, ESF and ESEF mice showed decreases in the heights and areas of villi and the total villus areas (perimeter). We observed frequent co-infections with various bacterial genera.
The ESEF mice showed a higher degree of sepsis. This finding may be associated with a reduction in the immune response associated with the absence of the spleen and a reduction in nutritional absorption strengthened by both of these factors (Schistosoma infection and splenectomy).