Subdural empyema caused by Peptostreptococcus sp.: a complication of acute pharyngitis

Metagenomic analysis of the salivary microbiota in patients with caries, periodontitis and comorbid diseases

Background/purpose

Previous studies have suggested that there is a mutual antagonism between caries and periodontitis. This research aimed to investigate the ecological connection and bacterial interaction of these two diseases.

Materials and methods

We profiled and analyzed the salivary microbiota from 124 individuals (including 38 caries patients, 34 periodontitis patients, 15 comorbid diseases patients, and 37 healthy controls) by using 16 S rRNA gene sequencing and bioinformatics approaches, and also quantified their salivary bacteria loads via quantitative real-time PCR. The putative biological functions of the salivary microbiome of the different groups were predicted by PICRUSt.

Results

We observed that both the total bacteria loads and the overall microbial richness in the saliva of the periodontitis group were higher than that in the healthy group. The principal coordinate analysis (PCoA) showed that the caries, periodontitis and healthy groups were separated from each other, and that the samples from comorbid diseases were located at the overlap of caries and periodontitis groups. Using LEfSe analysis, 20 differentially abundant genera were identified as potential biomarkers. These genera also performed complicated interactions among the four groups. Additionally, the PICRUSt analysis indicated caries-related and periodontitis-related functions (e.g., carbohydrate metabolism and bacteria proliferation) respectively.

Conclusion

We disclosed the significant differences in the salivary bacterial community under caries, periodontitis and comorbid diseases. The periodontitis group was marked by the increased complexity of the salivary microbiota. The result may have vital clinical significance to the screening and early treatment of caries-active and periodontitis-active individuals.

Pediatric subdural empyema as a complication of meningitis: could CSF protein/CSF glucose ratio be used to screen for subdural empyema?

Subdural empyema (SDE) is a rare condition which can appear secondary to meningitis in childhood, especially in infants. This study was planned to evaluate and compare clinical and laboratory features, treatment, and outcome of children with SDE to those with acute bacterial meningitis (ABM) without SDE. The electronic medical files of 266 patients diagnosed with ABM between January 2009 and December 2019 were evaluated. Patients' demographic and clinical features, laboratory results, cranial imaging findings, treatment, and outcomes were recorded. SDE was identified in 10 patients, 3.7% of all diagnosed with meningitis. The etiology of SDE was identified in eight (80%). The most common responsible pathogen was Streptococcus pneumoniae. Cranial imaging was performed between the 2nd and 13th days of admission, and the most common reason of performing cranial imaging was persistence of fever. Two patients were healed with 4-6 weeks of antibiotic treatment without surgery, eight (80%) needed surgical intervention.Conclusion: The clinical signs and symptoms of SDE may be subtle. If the fever persists or focal neurological findings are seen during the treatment of bacterial meningitis, SDE should be suspected. Furthermore, patients with ABM who are determined to have a protein-to-glucose ratio in the cerebrospinal fluid above 4.65 should be carefully monitored for SDE development. What is known: • Subdural empyema may develop subsequently to meningitis, especially in the infant age group in whom very little is known in terms of disease characteristics. • Delay in diagnosis and treatment can cause long-term neurologic sequelae and mortality. What is new: • Persistence or relapse of fever during the treatment of acute meningitis is an important warning sign for SDE even if there are no other symptoms. • Children with subdural empyema secondary to bacterial meningitis have higher protein-to-glucose ratio in the CSF, and a threshold of ˃ 4.65 was determined to demonstrate 100% sensitivity and 50.7% specificity.