Survey of the Oral and Intestinal Microbiome in Patients with Systemic Mastocytosis

Systemic Mastocytosis (SM) is characterized by an aberrant expansion of clonal mast cells in specific tissues including the skin, marrow, liver, and the gastrointestinal tract, which may cause symptoms such as abdominal pain, diarrhea, and weight loss. Demonstration of an interplay between these manifestations and the GI and oral microbiome in patients with SM is of interest. In addition to gathering clinical and laboratory information, we prospectively collected stool and buccal swab samples from 20 patients with SM and from 10 healthy volunteers (HVs). 16S rRNA sequencing identified bacterial phylogeny and taxonomy within the samples. Qiime2 workflow was employed and correlations between microbe abundance and demographic/clinical variables were determined. We observed no significant difference in microbial alpha-diversity but detected slight clustering in the PCoA plot of Bray Curtis beta-diversity between the patient and control groups. Lefse analysis identified unique Taxa amongst the Ruminococcaceae family that were significantly more abundant in patients with SM. In stool and buccal swabs, significant correlations were identified when comparing data from those with SM and HVs between specific taxa and clinical parameters including age, quality of life, bacterial translocation markers, liver fibroscan, serum alkaline phosphatase, and serum KIT D816V allelic frequency. Comparing stool and buccal swab samples in patients with SM and HVs, we found Alpha, and Beta-diversity were not significantly different. However, specific taxa correlated with relevant clinical and laboratory parameters, suggesting a possible impact of the microbiome on clinical disease in SM and the possible use of probiotics in management of disease symptoms.