Fig. 1Magnetic resonance imaging of the brain. Gadolinium-enhanced T1-weighted images show a ring-like enhancing lesion in the right frontal lobe.
Fig. 2Section of the brain showing radiating bacterial colony in the pyogranuloma.
Fig. 3Gram-positive (A) and acid fast-negative (B) filamentous organisms consistent with Actinomyces.
Table 1.Clinical features of central nervous system actinomycoses in Korea
No. |
Age (yr)/Sex |
Risk factor |
Clinical presentation |
Image |
Co-pathogen |
Treatment |
1 |
27/F |
None |
Headache, diplopia |
CT: 3.4 × 2.6 cm sized low density lesion with ring enhancement in right occipital lobe |
Haemophilus species |
I.V. ampicillin, metronidazole |
2 |
45/M |
Dental carries |
Generalized tonic-clonic seizure |
MR: 2.2 × 1.8 cm sized mass in right frontal lobe. Iso signal intensity lesion on T1WI. Peripheral low signal intensity with peripheral enhancement on T2WI |
Streptococcus species |
I.V penicillin-G |
Present case |
45/M |
Head trauma |
Motor weakness, drowsy consciousness |
CT: 3.5 × 2.5 cm sized low attenuated lesion with rim enhancement in right frontal lobe |
Streptococcus species |
Open resection I.V ampicillin |