Oral microbiota analyses of Saudi sickle cell anemics with dental caries

The objectives of this study were to identify the composition of oral microbiota in a cohort of patients with sickle cell anemia (SCA) and a high mean number of decayed, missing, and filled permanent teeth (DMFT) and compare it to a cohort of patients with SCA and a low number of DMFT and elucidate the effect of fetal haemoglobin levels on the oral microbiota composition.

Patients who had been diagnosed with SCA, who were homozygous for sickling β-globin mutation (β^S/β^S), who had Arab-Indian haplotype, and who ranged in age from 5 to 12 years were included in this study. Oral saliva from each participant (n = 100) was collected in GeneFiX™ Saliva DNA Microbiome Collection tube and DNA was extracted using GeneFiX™ DNA Isolation Kits. The composition of oral 16S rRNA from patients with SCA and high dental caries (n = 27, DMFT ≥5) and low dental caries (n = 73, DMFT ≤4) was analysed. Sequencing was performed on an Ion Personal Genome Machine using, Ion PGM Hi-Q view Sequencing 400-bp kit.

We observed an overall increase in abundance of Proteobacteria, Chloroflexi, and Bacteroidetes in the high DMFT index group compared to those with a low DMFT index. In addition, there was an overall increased abundance of microbiota from Proteobacteria, Fusobacteria, Firmicutes, and Bacteroidetes in the patients with SCA with low fetal haemoglobin compared to those with high fetal haemoglobin (P < .05). Enterobacteriaceae species were the most significant abundant species of bacteria found in both the high DMFT index group and low fetal haemoglobin cohort (P < .05).

Our data indicate that SCA in Saudi patients with high DMFT have a higher predominance of pathogenic bacteria compared to those with low DMFT. Furthermore, SCA in Saudi patients with low fetal haemoglobin have a higher predominance of pathogenic bacteria compared to those with higher fetal haemoglobin.