Gallium-67 Citrate in a Patient with Fever of Unknown Origin.

Case presentation:

• Male.
• 25 y.o.
• Clinical background: intermittent fever in the preceding 4 months, non quantitated weight loss and night sweats.
• Physical examination was unremarkable, except for hepatosplenomegaly.
• Initial lab test results: microcytic hypochromic anaemia (otherwise unremarkable).
• CT scan: bilaterally enlarged neck lymph nodes.
• Neck lymph node biopsy: negative.

Teaching points:

• There is a role for scintigraphy with gallium-67 citrate in patients with FUO, particularly if PET CT is unavailable.
• High quality images should be obtained: SPECT is mandatory.
• A positive gallium-67 scan can serve as guidance for the diagnostic biopsy as it will point out the most active lesions.
• SPECT CT obtained with hybrid gammacameras or by software fusion imaging can be useful for better lesion targeting.
• Gallium-67 citrate allows upfront whole body scanning which is useful, particularly in patients with lymphoma.
• This case illustrates the concept of tumor heterogeneity where certain tumor areas disclose different levels of gallium-67 avidity.