Isolated nocardial brain abscess in an immunocompetent patient with lung adenocarcinoma: A case report

Abstract

Brain metastases are common in non-small cell lung cancer (NSCLC) and can often be the presenting symptom. However, it is important to consider other etiologies for brain masses even in patients with a malignancy with a propensity to metastasize. We discuss the case of a 60 year-old immunocompetent male who presented with neurologic deficits thought to be secondary to brain metastases in the setting of an incidentally discovered lung cancer. Instead, the mass proved to be a rare isolated Nocardial brain abscess.

Keywords: Brain abscess; Case report; Immunocompetent; Nocardia; Non-small cell lung cancer.

Fig. 1

MRI of the brain. (A) DWI revealing a 2.8-cm tubular shaped heterogeneously enhancing mass within the right parietal lobe with extensive perilesional edema. There is irregular and nodular rim enhancement with some areas of restricted diffusion. (B) Apparent Diffusion Coefficient (ADC) map.

Fig. 2

PET/CT image demonstrating pronounced mediastinal lymphadenopathy in the right paratracheal, precarinal and subcarinal regions with markedly increased FDG activity.

Fig. 3

Brain lesion biopsy. Low power images showing an abscess with adjacent brain parenchyma (star). The surrounding brain parenchyma shows reactive gliosis on higher power.