Brain abscess mimicking a brain tumor only realized during surgery: A case report in a resource strained environment

Abstract

Background: Diagnosis of brain tumors increased in sub-Saharan Africa since the advent of computed tomography (CT)-scans and magnetic resonance imaging (MRI) in these regions, enabling easy diagnosis. However, some histological types of brain tumors can be confusing, especially on CT-scan, simulating other pathologies such as inflammatory granulomas or pyogenic abscesses. MRI, in this instance, with its diffusion-weighted imaging, susceptibility weighted imaging, or perfusion imaging, is important to help with accurate diagnosis. The down side of these imaging facilities, however, is that less and less importance is accorded to proper and detailed history taking. Such a care-free attitude to history taking can be costly, especially in resource strained environments.

Case description: We report the case of a 06-year-old child who presented with seizures associated with headaches and vomiting. In this case, proper history taking following the surgical intervention revealed a history of head trauma after a fall with a scalp wound, which was suppurated but later progressed well. The CT scan showed a solid cystic lesion. The first component is a ring enhanced portion (hyperdense ring with the hypodense center, surrounded by edema) with central calcification located in the frontal region, and the second component is a cystic portion located in the temporal region. This lesion with dual component was more suggestive of a tumoral lesion on imaging than an abscess. The child did not benefit from further imaging due to unavailability in the region as well as the socioeconomic status of the family making them incapable of going elsewhere to do it. A decision to surgically excise the lesion was made, and during surgery, we found a well-circumscribed yellowish lesion associated with an arachnoid cyst. The capsule of the lesion was very thick, and after opening it, the content was pus combined with debris. The child did well on antibiotic therapy post-surgery. The follow-up was unremarkable.

Conclusion: Brain MRI is essential to differentiate some pyogenic brain abscesses from tumors. However, meticulous history taking is important to gather as much information as possible about any medical pathology, which would then be corroborated with the physical examination findings and imaging to increase diagnostic accuracy and minimize misdiagnosis.

Keywords: Abscess; Brain tumor; Magnetic resonance imaging.

Figure 1:

Cerebral computed tomography (CT) scan, parenchymal window (a) without contrast and (b-d) with contrast. (a) It is an axial view showing a bony defect (blue arrow). (b) Shows an axial view of a cerebral CT scan showing a round lesion (orange arrow) with ring enhancement, a center with areas of hypodensity as well as hyperdensity (calcification) surrounded by perilesional edema (yellow arrow). (c) It is an axial view but lower than the slices in B, and it shows a cyst in the temporal lobe (green arrow). (d) It is a coronal view showing both lesions.

Figure 2:

Encapsulated yellowish lesion following cortectomy (blue arrow), edge of the bone flap (green arrow), open dura mater (black arrow), cottonoid placed between the normal brain, and the lesion during dissection (orange arrow). The cavity is left behind following complete excision (gray arrow).

Figure 3:

Lesion after complete excision.