Presentation
3 weeks headache. Recent diagnosis of colorectal carcinoma.
Patient Data
There is a 35 x 44 x 44 mm slightly lobulated, avidly rim enhancing lesion in the left parieto-occipital region. The lesion demonstrates a hypointense rim on T2 imaging, as well as marked central diffusion restriction. Significant amount of T2/FLAIR hyperintense signal abnormality surrounds the lesion, with mass effect causing effacement of overlying sulci. No significant midline shift.
Spectroscopy demonstrates metabolite depletion and high lactate peaks within the central portion. This lesion demonstrates diffusion restriction and slight contrast enhancement.
Conclusion
Large left parieto-occipital rim-enhancing lesion with surrounding vasogenic edema. Although potentially a metastasis (known primary colorectal carcinoma) the marked internal diffusion restriction and spectroscopy findings raise concern for a brain abscess.
Case Discussion
The patient went on to have a craniotomy and drainage.
Microbiology
- Specimen Type : Pus
- Description : Left occipital cerebral abscess Total specimen volume/size: 3.5mls
MICROSCOPY GRAM STAIN
- Leukocytes +
- No organisms seen
CULTURE
- Fusobacterium nucleatum +
- Staphylococcus capitis +
SENSITIVITIES
- Clindamycin S
- Cotrimoxazole S
- Erythromycin S
- Fusidic Acid S
- Oxacillin S
- Penicillin R
- Rifampin S
- Vancomycin S