Brain abscess caused by Streptococcus anginosus group:Three case reports

BACKGROUND This case series investigated the clinical manifestations,diagnoses,and treatment of cerebral abscesses caused by Streptococcus anginosus.We retrospectively analyzed the clinical characteristics and outcomes of three cases of cerebral abscesses caused by Streptococcus anginosus and conducted a comprehensive review of relevant literature.CASE SUMMARY Case 1 presented with a history of left otitis media and exhibited high fever,confusion,and vomiting as primary symptoms.Postoperative pus culture indicated a brain abscess caused by Streptococcus constellatus infection.Case 2 experienced dizziness for two days as the primary symptom.Postoperative pus culture suggested an intermediate streptococcal brain abscess.Case 3:Enhanced head magnetic resonance imaging(MRI)and diffusion-weighted imaging revealed occupancy of the left temporal lobe,initially suspected to be a metastatic tumor.However,a postoperative pus culture confirmed the presence of a brain abscess caused by Streptococcus anginosus infection.The three cases presented in this case series were all patients with community-acquired brain abscesses resulting from angina caused by Streptococcus group infection.All three patients demonstrated sensitivity to penicillin,ceftriaxone,vancomycin,linezolid,chloramphenicol,and levofloxacin.Successful treatment was achieved through stereotaxic puncture,drainage,and ceftriaxone administration with a six-week course of antibiotics.CONCLUSION Preoperative enhanced head MRI plays a critical role in distinguishing brain tumors from abscesses.Selecting the correct early diagnostic methods for brain abscesses and providing timely intervention are very important.This case series was in accordance with the CARE guidelines.

Streptococcus anginosus in the development and treatment of precancerous lesions of gastric cancer

The microbiota is strongly association with cancer.Studies have shown significant differences in the gastric microbiota between patients with gastric cancer(GC)patients and noncancer patients,suggesting that the microbiota may play a role in the development of GC.Although Helicobacter pylori(H.pylori)infection is widely recognized as a primary risk factor for GC,recent studies based on microbiota sequencing technology have revealed that non-H.pylori microbes also have a significant impact on GC.A recent study discovered that Streptococcus anginosus(S.anginosus)is more prevalent in the gastric mucosa of patients with GC than in that of those without GC.S.anginosus infection can spontaneously induce chronic gastritis,mural cell atrophy,mucoid chemotaxis,and heterotrophic hyperplasia,which promote the development of precancerous lesions of GC(PLGC).S.anginosus also disrupts the gastric barrier function,promotes the proliferation of GC cells,and inhibits apoptosis.However,S.anginosus is underrepresented in the literature.Recent reports suggest that it may cause precancerous lesions,indicating its emerging pathogenicity.Modern novel molecular diagnostic techniques,such as polymerase chain reaction,genetic testing,and Ultrasensitive Chromosomal Aneuploidy Detection,can be used to gastric precancerous lesions via microbial markers.Therefore,we present a concise summary of the relationship between S.anginosus and PLGC.Our aim was to further investigate new methods of preventing and treating PLGC by exploring the pathogenicity of S.anginosus on PLGC.

Autoimmune gastritis studies and gastric cancer: True renaissance or bibliometric illusion

A bibliometric analysis of studies dedicated to autoimmune gastritis(AIG)recently published demonstrated a noteworthy surge in publications over the last three years.This can be explained by numerous publications from different regions of the world reporting the results of several studies that stimulated reassessment of our view of AIG as a precancerous condition.Follow-up studies and retrospective analyses showed that the risk of gastric cancer(GC)in AIG patients is much lower than expected if the patients ever being infected with Helicobacter pylori(H.pylori)were excluded.The low prevalence of precancerous lesions,such as the incomplete type of intestinal metaplasia,may explain the low risk of GC in AIG patients because the spasmolytic polypeptide-expressing metaplasia commonly observed in AIG does not involve clonal reprogramming of the gastric gland and can be considered as an adaptive change rather than a true precancerous lesion.However,changes in gastric secretion due to the progression of gastric atrophy during the course of AIG cause changes in the gastric microbiome,stimulating the growth of bacterial species such as streptococci,which may promote the development of precancerous lesions and GC.Thus,Streptococcus anginosus exhibited a robust proinflammatory response and induced the gastritis-atrophy-metaplasia-dysplasia sequence in mice,reproducing the wellestablished process for carcinogenesis associated with H.pylori.Prospective studies in H.pylori-naïve patients evaluating gastric microbiome changes during the long-term course of AIG might provide an explanation for the enigmatic increase in GC incidence in the last decades in younger cohorts,which has been reported in economically developed countries.