ACE and lymphoproliferative syndrome: This patient was discussed with the hematology team who has advised for further investigations such as lactate dehydrogenase (LDH), hepatitis B antigen, serum hepatitis C antibody, HIV, angiotensin-converting enzyme (ACE), TB quantiferon, blood film (on the possibility that anything malignant or clonal can be identified), lumbar puncture with CSF analysis including cytospin, lymphoproliferative disorder panel, and radiology involvement to determine the biopsy site.