Microbial changes in relation to oral mucositis in autologous hematopoietic stem cell transplantation recipients

Abstract

The aim of this prospective, two center study was to investigate the dynamics of the microbial changes in relation to the development of ulcerative oral mucositis in autologous SCT (autoSCT) recipients. Fifty-one patients were diagnosed with multiple myeloma and treated with high-dose melphalan followed by autoSCT. They were evaluated before, three times weekly during hospitalization, and three months after autoSCT. At each time point an oral rinse was collected and the presence or absence of ulcerative oral mucositis (UOM) was scored (WHO scale). Oral microbiome was determined by using 16S rRNA amplicon sequencing and fungal load by qPCR. Twenty patients (39%) developed UOM. The oral microbiome changed significantly after autoSCT and returned to pre-autoSCT composition after three months. However, changes in microbial diversity and similarity were more pronounced and rapid in patients who developed UOM compared to patients who did not. Already before autoSCT, different taxa discriminated between the 2 groups, suggesting microbially-driven risk factors. Samples with high fungal load (>0.1%) had a significantly different microbial profile from samples without fungi. In conclusion, autoSCT induced significant and reversible changes in the oral microbiome, while patients who did not develop ulcerative oral mucositis had a more resilient microbial ecosystem.

Association of HSV-1 and Reduced Oral Bacteriota Diversity with Chemotherapy-Induced Oral Mucositis in Patients Undergoing Autologous Hematopoietic Stem Cell Transplantation

“…Therefore, HSV-1 may first trigger the development of OM, and dysbiotic oral bacteriota may aggravate the lesion. The association of decreased bacterial diversity with severe OM with ulceration coincides with the finding from the previous study by Laheji et al [23].…”

“…In our study, aberrant enrichment of Staphylococcus epidermidis, Enterococcus durans, or E. faecalis was observed in 7 patients. Five of the 7 patients had ulcerative OM, which partly agrees with the finding by Laheji et al [23]. However, enriched species varied from patient to patient, and no taxa showed a positive correlation with OMAS scores.…”

“…It has been reported that administration of systemic antibiotics is associated with the diversity loss of the gut microbiome in patients receiving allogeneic HSCT [22]. A very recent study by Laheji et al also reported decreased oral bacterial diversity after chemotherapy in patients who were undergoing autologous HSCT and received prophylactic ciprofloxacin [23]. The role of chlorhexidine cannot be excluded, although its effect on the structure of oral microbiota remains to be clarified.…”

“…Associations of Porphyromonas gingivalis and Fusobacterium nucleatum with oral ulceration were reported in a study where seven periodontopathic bacteria were tested by PCR in patients undergoing allogeneic HSCT [9]. Laheji et al [23] reported associations of Staphylococcus spp. and Enterococcus spp.…”

Female sex as an independent prognostic factor in the development of oral mucositis during autologous peripheral stem cell transplantation

“…In the preengraftment stage there is often anaerob blood stream infection (ABI) with Fusobacterium and Porphyromonas species of oral and upper GI tract origin, whereas during postengraftment Bacteroides and Clostridium species of lower GI tract origin colonize 40 . Changes in microbial diversity occure rapidly in patients with ulcerative oral mucositis during APSCT 41 . However, we did not find significant correlation between evidence of infection by haemoculture and ulcerative oral mucositis (OM2-4) in our retrospective study.…”