Pediatric Oncology
February 5, 2020


Case History:

A 42 years male presented with head and vertigo. Hematology revealed positive retrovirus status.


MRI brain with contrast revealed a large enhancing lesion with an alternate isointense-hypointense-hyperintense signal on T1/T2 and eccentric cystic area ( concentric target sign) in left basal ganglia causing mass effect and rightwards midline shift (Figure1).

Few small nodular enhancing lesions are also seen in the right basal ganglia (Figure 2).

MR spectroscopy revealed raised lipid-lactate, glutamine and decreased NAA and choline. The diagnosis of toxoplasmosis was given.

Figure 1( Axial DWI, T1, T2 and T1 Post-contrast images respectively)

Figure 2 (Axial T1 Post-contrast image, concentric target sign)

Figure 3. MR spectroscopy


CNS toxoplasmosis is an opportunistic infection in HIV positive status patients. The concentric target sign is pathognomic. MRS findings also support the diagnosis. A definitive diagnosis needs a brain biopsy. Follow is ongoing in this patient.


Roche D Adam
Volume 2018 |Article ID 9876514 | 3 pages |

Case Study Prepared by:

Dr. Deepak Garg
MD ( Radio-Diagnosis)
Fellowship in Body Imaging and Interventions( USA)
Fellowship in Vascular and Interventional Radiology ( USA)
Senior Consultant Diagnostic and Vascular Interventional Radiologist
@ H.O. D, Karkardooma, Delhi