Infection Route of Parvimonas micra: A Case Report and Systematic Review

Parvimonas micra Bacteremia: A Rare Complication After Esophagogastroduodenoscopy for Upper Gastrointestinal Bleeding

Parvimonas micra bacteremia is rarely encountered in clinical practice. When it is, patients usually have underlying periodontal disease or colorectal carcinoma. To the best of our knowledge, this is the first case of P. micra bacteremia in a patient without the predisposing risk factors listed above. We postulate that this occurred because of translocation across an interrupted gut-blood barrier in the setting of an acute upper gastrointestinal bleed. We present this case to highlight the importance of identifying and treating P. micra bacteremia because it can prevent commonly encountered sequelae of untreated bacteremia and improve outcomes.

Hemoptysis caused by Parvimonas micra: case report and literature review

Background

Parvimonas micra (P. micra), a Gram-positive anaerobic bacterium, exhibits colonization tendencies on oral mucosal and skin surfaces, potentially evolving into a pathogenic entity associated with diverse diseases. The diagnostic trajectory for P. micra-related diseases encounters delays, often with severe consequences, including fatality, attributed to the absence of symptom specificity and challenges in culture. The absence of a consensus on the diagnostic and therapeutic approaches to P. micra exacerbates the complexity of addressing associated conditions. This study aims to elucidate and scrutinize the clinical manifestations linked to P. micra, drawing insights from an extensive literature review of pertinent case reports.

Case presentation

A 53-year-old male sought medical attention at our institution presenting with recurrent hemoptysis. Empirical treatment was initiated while awaiting pathogen culture results; however, the patient's symptoms persisted. Subsequent metagenomic next-generation sequencing (mNGS) analysis revealed a pulmonary infection attributable to P. micra. Resolution of symptoms occurred following treatment with piperacillin sulbactam sodium and moxifloxacin hydrochloride. A comprehensive literature review, utilizing the PubMed database, was conducted to assess case reports over the last decade where P. micra was identified as the causative agent.

Conclusion

The literature analysis underscores the predilection of P. micra for immunocompromised populations afflicted by cardiovascular diseases, diabetes, orthopedic conditions, and tumors. Risk factors, including oral and periodontal hygiene, smoking, and alcohol consumption, were found to be associated with P. micra infections. Clinical manifestations encompassed fever, cough, sputum production, and back pain, potentially leading to severe outcomes such as Spondylodiscitis, septic arthritis, lung abscess, bacteremia, sepsis, and mortality. While conventional bacterial culture remains the primary diagnostic tool, emerging technologies like mNGS offer alternative considerations. In terms of treatment modalities, β-lactam antibiotics and nitroimidazoles predominated, exhibiting recovery rates of 56.10% (46/82) and 23.17% (19/82), respectively. This case report and literature review collectively aim to enhance awareness among clinicians and laboratory medicine professionals regarding the intricacies of P. micra-associated infections.

Bacterial Translocation As the Origin of Gram-Negative Rods Bloodstream Infection Among Older Patients in Rural Hospitals: A Cross-Sectional Study

Introduction Bloodstream infections caused by Gram-negative rods are a pressing concern for the aging global population, particularly in rural settings. This study investigates the prevalence and entry pathways of Gram-negative rod bloodstream infections in elderly patients at a rural Japanese hospital, aiming to clarify the frequency and associated factors of straightforward entry and bacterial translocation. Method In this cross-sectional study, we analyzed electronic medical records of patients over 18 years of age with symptomatic Gram-negative rod bloodstream infections at Unnan City Hospital, Japan, from September 2021 to August 2023. We used multivariate logistic regression to assess factors of age, sex, body mass index, care dependency, and comorbidities. Results Among the participants who met the inclusion criteria, significant differences were observed in age, sex, inpatient status, and prevalence of conditions like respiratory diseases and cancer between the straightforward entry and bacterial translocation groups. Escherichia coli was the most common pathogen identified. Conclusion The study emphasizes the need for tailored medical approaches for elderly patients with bloodstream infections, considering their unique health profiles and risks. It highlights the importance of age, inpatient status, and cancer in determining infection risks, pointing to areas for further research to enhance infection management and healthcare outcomes in older populations.

Anaerobic Spondylodiscitis caused by Parvimonas Micra in a Rheumatoid Arthritis Patient: Case Report and Review of the Literature

We report the rare case of Parvimonas micra bacteraemia and secondary spondylodiscitis probably triggered by tooth injury in a rheumatoid arthritis patient. Anaerobic bacteria associated spondylodiscitis may evade diagnosis due to atypical clinical presentation usually lacking fever, and the difficulties related to microbiological characterisation of the pathogen. Even though anaerobic spinal infections may constitute <3% of the total, clinical suspicion should remain high, especially in the case of positive history for pre-existing oral cavity or gastrointestinal/gynaecological tract infections.

Severe pneumonia with empyema caused by Parvimonas micra and Streptococcus constellatus co-infection: a case report

Empyema is a common complication of pneumonia, caused by the accumulation of purulent exudate due to pathogenic bacteria invading the pleural cavity. Parvimonas micra and Streptococcus constellatus are pathogens that rarely cause pneumonia with empyema. Herein, a case of severe empyema caused by these two pathogens, confirmed by metagenomic next-generation sequencing (mNGS) of pleural effusion cultures, is reported. A male Chinese patient in his late sixties presented with wheezing, cough, sputum expectoration, and fever. Blood and sputum cultures were negative for pathogens, but the pleural effusion culture was positive for S. constellatus, and was also found to contain P. micra, confirmed by mNGS. The patient's symptoms improved after treatment with cefoperazone/sulbactam and moxifloxacin. Pneumonia caused by P. micra and S. constellatus is rare; however, coinfection with these pathogens may cause severe pneumonia, with or without empyema.

A rare anaerobic cause of vertebral osteomyelitis and psoas abscess: A case study

Parvimonas micra is an obligate anaerobe that forms part of the normal gastrointestinal flora. The advent of matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF) and 16s ribosomal RNA gene sequencing has led to increased detection of many rare anaerobic isolates, including Parvimonas micra. Typical risk factors for Parvimonas micra bacteremia include dental procedures or spinal instrumentation. Here, we report a case of Parvimonas micra spondylodiscitis and psoas abscess in a patient with no obvious antecedent risk factors and explore the challenges in isolation of the organism from tissue samples.

Pediatric pulmonary infection caused by oral obligate anaerobes: Case Series

Background

Pneumonia is quite common in people with chronic bedridden, severe malnutrition and underlying diseases of cerebral palsy. Although poor oral hygiene and inadequate airway protection are risk factors, case reports of childhood pneumonia caused by oral obligate anaerobes are rare.

Introduction

We reported 4 cases of oral anaerobic pneumonia and empyema diagnosed by the pediatric intensive care unit (PICU) of our hospital.

Discussion

No bacteria were detected in sputum bacterial culture, pleural water bacterial culture and blood culture of the four children. Considering that multiple sputum cultures were negative, the pleural effusion and bronchoalveolar lavage fluid were subjected to next-generation sequencing (NGS) to identify the pathogen causing pneumonia. The results found oral obligate anaerobes represented by Parvimonas micra and Porphyromonas gingivalis. After identifying the pathogenic bacteria, we changed to piperacillin tazobactam combined with metronidazole for anti-infection treatment, and the pneumonia in the above patients was improved. In addition, all four patients had different basic medical histories, and long-term bed rest, severe malnutrition, poor oral hygiene and insufficient airway protection were all high risk factors for oral anaerobic pneumonia in these children.

Conclusion

Oral obligate anaerobes are one of the pathogens to consider for pneumonia in the elderly, but they may be easily overlooked in pediatric groups. Therefore, when receiving children with high-risk factors, we should be alert to the possibility of oral obligate anaerobic bacteria infection. Educating family members to pay attention to children's oral hygiene plays an important role in preventing oral obligatory anaerobic bacteria pneumonia. NGS can be used as a rapid diagnostic method when sputum culture cannot distinguish between pathogens.

Empyema and bacteremia caused by Parvimonas micra: A case report

Parvimonas micra is a gram-positive anaerobic coccus (GPAC) that colonizes the oral cavity and gastrointestinal tract. Recent advances in bacterial identification have confirmed the clinical importance of Parvimonas micra. Here, we report a case of empyema with bacteremia caused by Parvimonas micra. We successfully treated the patient with the appropriate antibiotics and drainage. Parvimonas micra can cause respiratory infections, including empyema, which can progress to bacteremia if treatment is delayed. In Parvimonas micra infections, not only the oral cavity but also the entire body must be investigated to clarify the entry mechanism.