Multiple hepatic and brain abscesses caused by Parvimonas micra: A case report and literature review

Parvimonas micra-induced prosthetic valve endocarditis: a challenging case report and literature review

Parvimonas micra, a gram-positive anaerobic bacterium, has garnered increased attention due to its role in infective endocarditis. We present a challenging prosthetic valve endocarditis caused by Parvimonas micra in a patient with a complex cardiac history involving multiple surgeries. The case highlights the difficulties in diagnosis and treatment, emphasizing the importance of advanced diagnostic techniques, including metagenomics next-generation sequencing (mNGS). Additionally, it underscores the need for heightened vigilance regarding oral symptoms and the potential risk of bacteremia in post-valvular surgery patients. This report contributes to a better understanding of Parvimonas micra-associated endocarditis and its unique characteristics.

Parvimonas micra orbital cellulitis complicated with cerebral venous thrombosis and mycotic aneurysm

Parvimonas micra is a gram-positive anaerobic coccus typically found in the human oral cavity, upper respiratory tract and gastrointestinal system. It occasionally causes intra-abdominal abscesses, spondylodiscitis and other infections. There are very few case reports on mycotic aneurysm related to P. micra We describe a rare case of P. micra orbital cellulitis complicated with meningitis, cerebral venous thrombosis and internal carotid artery mycotic aneurysm, which was successfully treated with the combination of endovascular therapy and antibiotics. Additionally, the patient received 6 months of anticoagulation therapy for cerebral venous thrombosis.

Stroke Caused by Vasculitis Induced by Periodontitis-Associated Oral Bacteria after Wisdom Teeth Extraction

Invasive dental procedures, such as wisdom teeth removal, have been identified as potential triggers for vascular events due to the entry of oral bacteria into the bloodstream, leading to acute vascular inflammation and endothelial dysfunction. This study presents the case of a 27-year-old healthy male who developed ischemic stroke resulting from bacteremia after undergoing wisdom teeth extraction. Initially, the patient experienced fever and malaise, which were followed by right-sided hemiplegia. Diagnostic imaging, including a CT scan, identified a subacute infarction in the posterior crus of the left internal capsule, and MRI findings indicated inflammatory changes in the masticatory muscles. Further investigations involving biopsies of the masticatory muscles, along with blood and cerebrospinal fluid samples, confirmed bacterial meningitis with associated vasculitis. Notably, oral bacteria linked to periodontitis, including Porphyromonas gingivalis, Fusobacterium nucleatum, Tannerella forsythia, and Parvimonas micra, were found in the biopsies and microbiological analyses. To the best of our knowledge, this is the first reported case showing that bacteremia following dental procedures can lead to such severe neurological outcomes. This case underscores the importance of recognizing bacteremia-induced vasculitis in patients presenting with neurological symptoms post-dental procedures, emphasizing the broader implications of oral infections in such pathologies.

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.

Case Report and Literature Review of Parvimonas micra: Difficult-to-Treat Arthritis in Hiding

Septic arthritis is a life-threatening rheumatological syndrome that is highly related to a patient's immune status and comorbidities, and although the most common clinical presentation is rapid-onset monoarthritis, it can also appear as subacute or chronic joint swelling. In these cases, differential diagnosis is more challenging, but early diagnosis and treatment is no less urgent to ensure a good global prognosis and the best outcome of the affected joint. Anaerobic microorganisms, such as Parvimonas micra, are an uncommon cause of septic arthritis (less than 5% of cases) but may be the cause of subacute arthritis. Knowledge about Parvimonas micra is important, as it is difficult to culture in the laboratory and generates a synovial fluid with atypical characteristics for septic arthritis so that, if not suspected, its diagnosis can be easily overlooked and underdiagnosed. We present the case of a 76-year-old woman with subacute arthritis of the left knee, describe the difficult diagnosis and treatment of its unexpected cause (Parvimonas micra), and review previously described cases, identifying the possible common comorbidities that may help clinicians easily find and treat this cause of subacute septic arthritis.

Parvimonas micra a new potential pathogen in hospitalized patients: a case series from 2015-2022

Parvimonas micra isolations are usually part of polymicrobial infections and the pathogenic role of this microrganism is still debated. We describe here a large series of hospitalized patients diagnosed with Parvimonas micra infections and discuss the clinical and therapeutic management and the outcome of these infections.

Brain abscess caused by Parvimonas micra: A rare case report and literature review

Brain abscesses mostly develop due to direct infection caused by a nearby infectious lesion or hematogenous spread and are rarely caused by an odontogenic infection. We report a 47-year-old woman who presented with high fever, disturbed consciousness, headache, and neck pain. Imaging studies revealed a ring-shaped enhanced mass in the left frontal lobe causing a mass effect and midline shift. Magnetic resonance spectroscopy revealed a peak alanine concentration of 1.5 ppm. Supraorbital keyhole surgery with abscess removal was performed, and a bacterial culture confirmed a diagnosis of Parvimonas micra infection. After undergoing 6-week antibiotic treatment, the patient's symptoms resolved completely. No recurrence of abscess was observed during the follow-up period. Although brain abscess caused by P. micra has rarely been reported, an odontogenic origin should be investigated, especially when a patient has a history of periodontal infection or tooth extraction.

Case report: Successful management of Parvimonas micra pneumonia mimicking hematogenous Staphylococcus aureus pneumonia

Parvimonas micra is an anaerobic Gram-positive coccus frequently found in the oral cavity and gastrointestinal tract, but rarely in the lung. Therefore, pneumonia caused by P. micra is also rare. Although there are some reports of P. micra related pneumonia due to aspiration or blood-borne infection with definite remote infection source, there are no reported cases of hematogenous P. micra pneumonia in healthy adults lacking a remote source of infection. Herein, we described the intact disease of P. micra-related pneumonia mimicking hematogenous Staphylococcus aureus pneumonia in terms of chest imagery and diagnosed via metagenomic next-generation sequencing (mNGS). Interestingly, there was no clear remote pathogenic source identified in the patient. Microbiome analysis revealed dysbiosis of the oral flora possibly related to poor oral hygiene and a long history of smoking. The patient was treated with moxifloxacin for 3 months. Ultimately, computed tomography (CT) of the chest showed total resolution of the lung lesion. Clinicians need to update the etiology of community-acquired pneumonia. When antibiotic therapy is not effective, pathogen examination becomes very important. New methods of pathogen detection such as mNGS should be employed to this end. For the treatment of P. micra pneumonia, no standardized course of treatment was reported. Imaging absorption of lung infections may provide a more objective guidance for the duration of antibiotics in P. micra pneumonia.

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

Parvimonas micra (P. micra), a bacterium that colonizes the gastrointestinal tract, is often isolated from periodontitis and abscesses as part of a complex bacterial infection. However, reports of monobacterium infections due to P. micra are limited. Here, we report a case of monobacterial bacteremia caused by P. micra with the aim of identifying the source of the invasion and clarifying the clinical features. A 54-year-old patient presented with bacteremia due to P. micra and with an oral invasion that we suspected resulted from prior dental treatment. Using PubMed and Google Scholar databases, we undertook a systematic review of monobacteremia caused by P. micra. We identified 26 patients (mean age, 70.15 years) in our systematic review. P. micra bacteremia and its associated phenotypes were most frequently identified in spinal discitis, followed by epidural and lumbar abscesses, and infective endocarditis. The major risk factors were malignancy, diabetes mellitus, and post-arthroplasty. When P. micra is detected in blood cultures, evaluation and intervention for oral contamination may be indicated.