Endobronchial Enigma: A Clinically Rare Presentation of Nocardia beijingensis in an Immunocompetent Patient

Brain abscesses: the first report of disseminated Nocardia beijingensis infection in an immunocompetent individual in China

Nocardia is widely distributed in the natural environment and typically cause opportunistic infections. However, it is important to note that the pathogenicity of different Nocardia species may vary significantly. Here we reported the first case of brain abscess caused by Nocardia beijingensis (N. beijingensis) infection in China. A 70-year-old male immunocompetent individual came to our hospital for treatment due to headache. After examination, it was found that he had a brain abscess caused by N. beijingensis. By utilizing a combination of surgical intervention and antibiotic therapy, the patient ultimately achieved full recovery. In addition, we isolated this strain and displayed its ultrastructure through scanning electron microscopy. The phylogenetic tree was analyzed by 16 S rRNA sequence. A literature review of N. beijingensis infections in all immunocompetent and immunocompromised patients was presented. It highlighted that abscess formation appears to be a common manifestation of N. beijingensis infection, and N. beijingensis has become an emerging pathogen in immunocompetent individuals.

Persistent Nocardia beijingensis infection in a patient with postoperative abscess and misuse of antibiotics in China

Here we describe the first case of abscess infection caused by Nocardia beijingensis in China. The patient was immunocompetent but suffered from postoperative abscess for 6 years. This study highlights the necessity of long-term infected foci to be thoroughly examined to identify the pathogen, as well as the importance of accurate Nocardia identification and antimicrobial susceptibility tests for understanding the pathogen's epidemiology, clinical significance, and treatment strategy.

Stroke like presentation of disseminated CNS Nocardia beijingensis infection in an immunocompetent patient: Case report and review of the literature

We describe a rare case of pulmonary and central nervous system (CNS) Nocardia beijingensis infection in an immunocompetent patient presenting with stroke like symptoms and newly discovered pulmonary and brain mass. Initial work up suggested lung cancer with metastasis to the brain. However, further evaluation revealed disseminated N. beijingensis. A literature review of N. beijingensis infections in immunocompetent host is also presented.

Disseminated Nocardia beijingensis Infection in an Immunocompetent Patient

Nocardia is a genus of aerobic, non-motile and non-spore-forming filamentous branching bacteria with fragmentation into bacillary or coccoid forms. Infections caused by Nocardia often occur in immunocompromised hosts and are potentially life-threatening. Nocardia beijingensis has rarely been reported to cause infection in immunocompetent hosts. We present a case of disseminated infection due to Nocardia beijingensis in a patient with no known medical comorbidities, who presented with new-onset seizure. Another interesting finding in our case is that our patient did not have any pulmonary symptoms despite chest CT showing the pulmonary system as the likely primary site of infection. As per our literature review, this is the seventh reported case of infection due to Nocardia beijingensis in an immunocompetent host.

LEARNING POINTS

To recognize Nocardia beijingensis, a slow-growing weakly acid-fast filamentous bacteria commonly causing opportunistic infections in immunocompromised hosts, as an emerging pathogen in immunocompetent patients.Tissue biopsy with Gram staining showing variable filamentous bacteria and confirmation of species using restriction enzyme analysis and 16S rRNA analysis is needed to establish a diagnosis of infection.Trimethoprim/sulfamethoxazole has been successfully used to treat infection due to Nocardia beijingensis.

Nocardia beijingensis brain abscesses in an HIV-infected individual

We describe a case of a 50-year-old Hispanic man diagnosed with HIV/AIDS who presented with a generalized tonic clonic seizure and ring enhancing cerebral lesions on imaging. He was initially treated for CNS toxoplasmosis but presented to the hospital with another tonic clonic seizure despite prescribed therapy. Brain biopsy was performed which revealed Nocardia beijingensis. He was treated with intravenous meropenem and trimethoprim/sulfamethoxazole for six weeks followed by long term oral trimethoprim/sulfamethoxazole with radiographic and clinical improvement.