Nocardia farcinica

• Multiple brain abscesses caused by Nocardia farcinica: A rare case report
• PD-Like Pathogenesis in Caenorhabditis elegans Intestinally Infected with Nocardia farcinica and the Underlying Molecular Mechanisms
• How an Antimicrobial Stewardship Team Treated a Nocardia farcinica-Associated Brain Abscess: A Case Report
• Disseminated Nocardia farcinica Infection in a Renal Transplant Patient: A Case Report
• Post-neurosurgical Nocardia meningoventriculitis: a case report and review of the literature
• Nocardia farcinica pituitary abscess in an immunocompetent patient: illustrative case
• Brain Abscesses Caused by Nocardia farcinica in a 44-Year Old Woman with Multiple Myeloma: A Rare Case and Review of the Literature
• Intratumoral and Peritumoral Brain Abscess Concomitant with Glioblastoma: Report of Two Cases with Review of Literature

Nocardia farcinica is a species of bacteria and a member of the genus Nocardia. This species is very similar in phenotype to Nocardia asteroides, to the degree that some isolates of N. asteroides were later found to be Nocardia farcinica.

The research yielded 54 articles for a total of 58 patients. N. farcinica cerebral abscess displayed three different neuroimaging patterns: a single multiloculated abscess in half of the cases, multiple cerebral abscesses, or a small paraventricular abscess with meningitis. The patients who benefited from surgical excision of the abscess showed a trend towards a lower risk of surgical revision (8% versus 31%, P=0.06) and a lower mortality rate (8% versus 23%, P=0.18) than patients who benefited from needle aspiration. Twenty-two percent of the patients benefited from microbiological documentation from another site with a mortality rate of 23%.

Urgent multimodal MRI is necessary for the face with clinical suspicion of cerebral nocardiosis. In the case of single or multiple small cerebral abscesses, microbiological documentation can be obtained with the puncture of pseudotumoral visceral lesions. In case of a large or symptomatic cerebral abscess, an aggressive surgical excision seems a reliable option and can be preferred over needle aspiration. Long-term antibiotic therapy with cotrimoxazole is necessary after that ¹⁾.

A 47-year-old woman underwent an endoscopic third ventriculostomy and a left retrosigmoid craniotomy for a schwannoma removal. Meningeal symptoms began a week later, in association with C reactive protein rise and leukocytosis. The cerebrospinal fluid analysis examination was clear with hypoglycorrhachia, hyperprotidorrachia, and polymorphonuclear cells. The bacteria culture test was negative. At the brain magnetic resonance imaging (MRI) purulent material was described in the occipital horns. Empirical broad-spectrum antibiotics was given for 31 days until the brain MRI showed a resolution of the infection. Ten days later, the patient was admitted to the hospital because of new meningitis symptoms. Cerebrospinal fluid culture and Polymerase-chain reaction (PCR) Multiplex for the most important meningitis viruses and bacteria tested negative. A broad-spectrum antibiotic therapy was started with no benefit; thus, a broad-spectrum antifungal therapy was added with little success on clinical status. Meanwhile, a 16s and 18s rRNA PCR was executed on a previous Cerebrospinal fluid with negative results, excluding bacterial and fungal infections. For this reason, all the therapies were stopped. After a few days, high fever and meningeal signs reappeared. The brain MRI showed a meningoventriculitis. An Ommaya catheter with a reservoir was inserted and the drawn CSF resulted in the growth of Nocardia farcinica. Antibiogram-based antibiotic therapy was started with intravenous imipenem and trimethoprim-sulfamethoxazole, showing clinical benefit. The patient was sent home with oral linezolid and amoxicillin/clavulanate for a total of 12 months of therapy. Nocardia rarely causes post-neurosurgical complications in a nosocomial setting. This case shows the difficulty in detecting Nocardia and the importance of the correct microbiological sample and antibiogram-based antibiotic therapy to achieve successful treatment ²⁾.

The first case of Nocardia brain abscesses in a patient with multiple myeloma, without the above risk factors. CASE REPORT A 44-year-old woman with IgG-kappa type multiple myeloma presented with generalized tonic-clonic seizures. Magnetic resonance imaging of the brain revealed 3 space-occupying lesions in the left frontal, left parietal, and right parietal regions. Craniotomy and enucleation of the left frontal lesion revealed an abscess. The culture result was Nocardia farcinica. The patient was treated with meropenem, amikacin, and trimethoprim-sulfamethoxazole for 6 weeks, followed by trimethoprim-sulfamethoxazole for 12 months, with good outcome. CONCLUSIONS Cerebral nocardiosis is a rare entity and its occurrence in our case may hint toward myeloma-associated humoral immune dysfunction as a pathogenesis and the importance of humoral immunity in the defense against this infection. However, chemotherapy-induced cell-mediated dysfunction cannot be ruled out as a risk factor for the infection. Despite its rarity, this case aims to raise awareness of the condition and reiterate the importance of considering the rare but life-threatening conditions in the differential diagnosis of brain lesions, especially when there is a misdiagnosis of the radiological findings, as occurred in this and previous cases; this avoids delays in appropriate surgical and medical treatment, which can affect outcomes ³⁾

Nocardia farcinica abscess surrounding the glioblastoma in an immunocompromised individual ⁴⁾

A 44-year-old man presented with hemoptysis and was found to have a cavitary right lung nodule, which was presumed histoplasmosis, prompting antifungal treatment. Several months later, he developed panhypopituitarism. Magnetic resonance imaging identified a pituitary mass, which subsequently underwent transsphenoidal endoscopic biopsy. Infectious workup was negative, and the patient was discharged on intravenous ertapenem therapy. Over several months, he developed progressive headaches, and updated imaging confirmed interval enlargement of the mass with new cavernous sinus invasion. He underwent repeat endoscopic biopsy, which yielded positive cultures for Nocardia farcinica and prompted successful treatment with trimethoprim-sulfamethoxazole and linezolid.

The current study highlights a previously unreported clinical entity, the first pituitary abscess attributable to Nocardia sp. or N. farcinica, which arose in a young, immunocompetent individual. Although rare, atypical infections represent an important component in the differential diagnosis for sellar mass lesions ⁵⁾.

A patient with primary brain abscesses due to Nocardia Farcinica, was successfully treated with intrathecal Amikacin administration through the ventricular drain, in addition to surgical evacuation and intravenous antibiotic therapy. In this case, clinical and radiological improvements were observed once the intrathecal treatment was started. To our best knowledge, no cases of intraventricular use of Amikacin have been previously reported to treat this type of infection and we believe that it may be useful in properly selected patients ⁶⁾.

An extremely rare case of cauda equina syndrome due to isolated intramedullary Nocardia farcinica infection. A 44-year-old male presented with low backache and gradually progressive weakness in bilateral lower limbs followed by paraplegia. He was found to have a well-defined, sharply demarcated ring-enhancing lesion located from T11-T12 to L3 vertebral body. He underwent laminectomy and decompression. The histopathological examination revealed a Gram-positive filamentous organism that looks like Nocardia. The culture report was suggestive of Nocardia farcinica. He was then treated with antibiotics and had remarkable clinical and radiological improvement ⁷⁾.

Galacho-Harriero et al. present three cases of Nocardia farcinica brain abscess (single, multi-loculated and multi-focal) diagnosed in three patients with predisposing factors that could be successfully cured. The patients underwent craniotomy, evacuation of the purulent collection and partial resection of the abscesses' walls. Confirmation of Nocardia farcinica species was achieved using specific PCR sequencing of the 16S ribosome RNA gene. Antibiotic therapy was selected upon susceptibility tests and was maintained for 10 (one case) and 12 months (two cases).

Brain nocardiosis needs to be suspected primarily (though not exclusively) in immunocompromised patients presenting with neurological deficits and harboring intracerebral lesions resembling brain tumors. Early identification of the specific species is paramount in order to initiate long-term antibiotic therapy, acknowledging the inherent resistance of Nocardia farcinica to third-generation cefalosporins and its susceptibility to trimethoprim-sulphamethoxazole. According to the literature, surgical excision or aspiration of the brain abscess seems to provide good chances of eradication of the disease. In our experience, successful outcome was achieved with subtotal resection and prolonged and adequate antibiotic therapy ⁸⁾.