Intracranial tuberculomas diagnosed with Xpert MTB/RIF Ultra assay of formalin-fixed paraffin-embedded brain tissues and treated with an optimized antituberculosis regimen: A case report

Abstract

Diagnosis of intracranial tuberculoma remains a challenge due to its rarity, non-specific clinical presentation, and radiological findings. Herein, we describe a case of intracranial tuberculomas in a male diabetic patient who presented headache and vomiting on admission. Neuroimaging findings indicated multiple ring contrast-enhanced lesions with extensive perilesional edema. However, a cerebrospinal fluid (CSF) examination was normal. When a biopsy of brain lesions was performed, pathological characteristics of tuberculosis were absent and acid-fast staining was negative. A tuberculosis diagnosis was subsequently obtained from an Xpert MTB/RIF Ultra assay of formalin-fixed paraffin-embedded brain tissue. The patient was treated with an optimized anti-tuberculosis regimen which included high-dose intravenous administration of rifampicin and isoniazid, and oral administration of linezolid. The patient recovered well and exhibited marked clinical improvement. This case report demonstrates that when CSF analysis does not indicate the presence of intracranial tuberculomas, analysis of formalin-fixed paraffin-embedded brain tissue specimens with the Xpert MTB/RIF Ultra assay may be able to confirm a diagnosis. Furthermore, a high dose of rifampicin and isoniazid plus linezolid may improve patient outcome.

Keywords: Brain biopsy; Case report; Intracranial tuberculoma; Xpert MTB/RIF Ultra assay.

Fig. 1

MRI images. A MRI scan performed on July 22 showed multiple lesions in both frontal and parietal lobes of the patient. In addition, perilesional edema, high signal intensity on T2-weighted image (T2WI), low signal intensity on T1-weighted image (T1WI), and circular or nodular enhancement following administration of contrast agent were observed. After 3 months of treatment (Oct 24), MRI re-examination showed significant absorption of the lesions (white and yellow arrows). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 2

Pathologic features of brain biopsy specimens from the patient. (A) A gross specimen of a biopsied brain lesion from the patient. (B) Histopathological analysis showed the brain parenchyma modified by fibroblasts and epithelioid cells infiltrated with polymorphic inflammatory cells (lymphocytes, monocytes, neutrophils, and a few plasma cells) and poorly formed granulomas. The sections were stained with hematoxylin-eosin (H&E) and examined by light microscopy (magnification, 200 × ).