Moraxella osloensis infection among adults and children: A pediatric case and literature review

A rare case of acute meningitis caused by Moraxella osloensis

Meningitis caused by Moraxella osloensis is rare and easily misdiagnosed clinically. Here, we report the first case of meningitis caused by M. osloensis in China by taking advantage of the metagenomic next-generation sequencing technology in cerebrospinal fluid for pathogen screening. In addition, we extend the neurological signs, clinical symptoms, diagnostic methods, and treatment of this rare disease.

Changes in the Microbiome in Yak Mastitis: Insights Based on Full-Length 16S rRNA Sequencing

Mastitis is an inflammation of the mammary gland that can be caused by various factors, including biological, chemical, mechanical, or physical. Microbiological culture, DNA techniques, and high-throughput next-generation sequencing have been used to identify mastitis-causing pathogens in various animal species. However, little is known about microbiota and microbiome changes linked to yak milk mastitis. This study aimed to characterize the milk microbiota of healthy and mastitis-infected yaks using full-length 16S rRNA sequencing. The results showed that the bacterial microbiota comprises 7 phyla, 9 classes, 20 orders, 39 families, 59 genera, and 72 species. Proteobacteria and Firmicutes were the predominant microbial communities, with lower abundances of Bacteroidota, Actinobacteriota, Acidobacteriota, and other minor groupings also observed. Proteobacteria dominated the clinical and subclinical mastitis groups (95.36% and 89.32%, respectively), in contrast to the healthy group (60.17%). Conversely, Firmicutes were more common in the healthy group (39.7%) than in the subclinical and clinical mastitis groups (10.49% and 2.92%, respectively). The predominant organisms found in the healthy group were Leuconostoc mesenteroides, Lactococcus piscium, Carnobacterium maltaromaticum, and Lactococcus raffinolactis. Low abundances of Staphylococcus aureus species were found in both subclinical and clinical mastitis groups, with Moraxella osloensis and Psychrobacter cibarius dominating the subclinical mastitis group and Pseudomonas fluorescens dominating the clinical mastitis group. An alpha diversity study revealed that the healthy group had a higher microbial diversity than the clinical and subclinical mastitis groups. According to beta-diversity analysis, the principal coordinate analysis identified that mastitis-infected samples significantly differed from healthy ones. The milk microbiota of healthy yaks is more varied, and specific prominent taxa within various groups can act as marker microorganisms for mastitis risk. The genera Leuconostoc and Lactococcus are promising candidates for creating probiotics.

Postpolypectomy syndrome without abdominal pain led to sepsis/septic shock and gastrointestinal bleeding: A case report

BACKGROUND

Postpolypectomy syndrome (PPS) is a rare postoperative complication of colonic polypectomy. It presents with abdominal pain and fever accompanied by coagulopathy and elevated inflammatory markers. Its prognosis is usually good, and it only requires outpatient treatment or observation in a general ward. However, it can be life-threatening.

CASE SUMMARY

The patient was a 58-year-old man who underwent two colonic polypectomies, each resulting in life-threatening sepsis, septic shock, and coagulopathy. Each of the notable manifestations was a rapid drop in blood pressure, an increase in heart rate, loss of consciousness, and heavy sweating, accompanied by shortness of breath and decreased oxygen in the finger pulse. Based on the criteria of organ dysfunction due to infection, we diagnosed him with sepsis. The patient also experienced severe gastrointestinal bleeding after the second operation. Curiously, he did not complain of any abdominal pain throughout the course of the illness. He had significantly elevated concentrations of inflammatory markers and coagulopathy. Except for the absence of abdominal pain, his fever, significant coagulopathy, and elevated inflammatory marker concentrations were all consistent with PPS. Abdominal computed tomography and superior mesenteric artery computed tomography angiography showed no free air or vascular damage. Thus, the diagnosis of colon perforation was not considered. The final blood culture results indicated Moraxella osloensis. The patient was transferred to the intensive care unit and quickly improved after fluid resuscitation, antibiotic treatment, oxygen therapy, and blood transfusion.

CONCLUSION

PPS may induce dysregulation of the systemic inflammatory response, which can lead to sepsis or septic shock, even in the absence of abdominal pain.

Moraxella nasibovis sp. nov., Isolated from a Cow with Respiratory Disease

Strain ZY190618T, isolated from the nasal cavity of a cow with respiratory disease, was subjected to taxonomic characterization. Cells of the strain were Gram-stain-negative, aerobic and coccus-shaped. Phylogenetic analysis based on 16 S rRNA gene sequences indicated that the strain belonged to the genus Moraxella with the highest similarity of 98.1% to Moraxella nasovis CCUG 75922T. Phylogenomic analysis based on 810 single-copy genes revealed that the strain was a member of the genus Moraxella and formed a deep and separated clade within the genus. The strain showed the highest orthologous average nucleotide identity (OrthoANI) value of 77.1% with Moraxella ovis CCUG 354T and digital DNA-DNA hybridization (dDDH) value of 24.7% with Moraxella equi NCTC 11012T, respectively. The DNA G + C content was 46.5 mol%. The strain optimally grew at 37 °C (temperature range, 24-42 °C), at pH 8.0 (pH range, 6.0-9.0) and with 1.5% (w/v) NaCl (NaCl range, 0.5-3.0%). The strain contained C18:1 ω9c as the sole predominant fatty acid (> 5 %) and CoQ-8 as the major respiratory quinone. The major polar lipids included phosphatidylglycerol, phosphatidylethanolamine, cardiolipin, monolysocardiolipin and hemibismonoacylglycerophosphate. Based on these data, strain ZY190618T clearly represents a novel species in the genus Moraxella, for which the name Moraxella nasibovis sp. nov. (The type strain ZY190618T = CCUG 75921T = CCTCC AB 2021472T) is proposed.

Moraxella nasicaprae sp. nov., Isolated from a Goat with Respiratory Disease

A novel Gram-stain-negative, aerobic, irregular coccus designated as ZY201224^T, was isolated from the nasal cavity of a goat with respiratory disease in a goat farm, located at Jianshui, Yunnan Province, PR China and its taxonomic position was clarified using a polyphasic approach. The strain grew optimally at 37 °C, at pH 8.0 and in the presence of 1% NaCl. Phylogenetic analysis based on 16S rRNA gene sequence and phylogenomic analysis based on 808 single-copy genes revealed that the strain is affiliated to the genus Moraxella and is distinct from the recognized species of the genus. The 16S rRNA gene sequence similarity analysis indicated that the strain is most closely related to Moraxella caviae CCUG 355^T with sequence similarity of 98.1%. The genomic OrthoANI and digital DNA-DNA hybridization (dDDH) values between the strain and the type strains of Moraxella species were no higher than 74.7% (Moraxella pluranimalium CCUG 54913^T) and 26.0% (Moraxella oblonga NBRC 102422^T), respectively. The G + C content of the complete genome sequence was 43.6 mol%. The strain contained CoQ-8 as the major respiratory quinone, and C_18:1ω9c, C17:1ω8c, C16:0 and summed feature 3 (C_16:1 ω7c and/ or C_16:1ω6c) as the predominant fatty acids (> 5%). The major polar lipids comprised phosphatidylglycerol (PG), cardiolipin (CL), monolysocardiolipin (MLCL), phosphatidylethanolamine (PE) and lysophosphatidylglycerol (LPG). Based on these taxonomic characterizations, strain ZY201224^T represents a novel species of the genus Moraxella, for which the name Moraxella nasicaprae sp. nov. is proposed. The type strain is ZY201224^T (= CCTCC AB 2021474^T = NBRC 115473^T).

Moraxella nasovis sp. nov., isolated from a sheep with respiratory disease

A novel Gram-stain-negative, aerobic, coccus-shaped bacteria, designated ZY201115T, was isolated from the nasal cavity of a sheep with respiratory disease in Yunnan Province, south-west China, and its taxonomic affiliation was studied by applying a polyphasic approach. The strain grew at 18–41 °C (optimum, 37 °C), at pH 6.0–9.0 (optimum, pH 8.0) and in 0.5–3.0% (w/v) NaCl (optimum, 1.0 % NaCl). Phylogenetic analysis based on 16S rRNA gene sequences showed that the strain is affiliated to the genus Moraxella with highest similarity to Moraxella bovis ATCC 10900T (96.6 %). Phylogenomic analysis based on 811 single-copy genes also indicated that the strain represents a novel species in the genus Moraxella and formed a deep and separated clade with Moraxella caviae NCTC 10293T. The highest genomic orthologous average nucleotide identity and digital DNA–DNA hybridization values between the strain and the type strains in the genus Moraxella were 73.7% ( M. caviae NCTC 10293T) and 25.3% ( Moraxella osloensis CCUG 350T), respectively. The G+C content of the complete genome sequence was 42.1 mol%. The predominant fatty acids (>5 %) were C18:1 ω9c, C17:1 ω8c, C12:03OH and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c). The major polar lipids were phosphatidylglycerol, cardiolipin, monolysocardiolipin, phosphatidylethanolamine and hemibismonoacylglycerophosphate. The major respiratory quinone was CoQ-8. On the basis of the results of phylogenetic, phenotypic and chemotaxonomic characterizations, strain ZY201115T clearly represents a novel species of the genus Moraxella , for which the name Moraxella nasovis sp. nov. is proposed. The type strain is ZY201115T (=CCTCC AB 2021473T=CCUG 75922T).

Maturation of the oral microbiota during primary teeth eruption: a longitudinal, preliminary study

Introduction

Oral microbiota that established in the early years of life may influence the child’s oral health in the long term. Until now, no consensus is reached about whether the development of the oral microbiota is more related with age increase or more with teeth eruption.

Objective

To analyze the microbiota development of both saliva and supragingival plaque during the gradual eruption of primary teeth in caries-free infants and toddlers.

Methods

Saliva and plaque samples were collected at five and four dentition states, respectively, and were identified by bacterial 16S rRNA gene sequencing.

Results

During the longitudinal observation, the saliva ecosystem seemed more complex and dynamic than the plaque, with larger bacteria quantity and more significantly varied species over time. About 70% of the initial colonized OTUs in plaque persisted until the completion of the primary dentition. Transient bacteria were mostly detected in the early saliva and plaque microbiota, which came from the environment and other sites of the human body. Microbial diversity in both saliva and plaque varied greatly from pre-dentition to full eruption of eight anterior teeth, but not during the eruption of primary molars.

Conclusion

Oral bacterial development follows an ordered sequence during the primary teeth eruption. ‘Fully eruption of all primary anterior teeth’ is a critical stage in this process.