Objectives Lymphomatoid granulomatosis is a rare Epstein Barr virus (EBV) associated lymphoproliferative disorder. It most commonly involves the lung, but may also include other extra-nodal sites such as skin and central nervous system (CNS) to a lesser extent.¹ Due to the insidious nature of the condition, along with variable radiological findings, it remains a diagnostic challenge.^1,2 Histopathology remains the gold standard for diagnosis, although subsequent prognosis is poor.^1,3 We report a rare case of CNS lymphomatoid granulomatosis without pulmonary involvement in an immunocompromised patient who presented with subacute cognitive decline. This was a personal case of the author, with documentation and investigations accessed from medical records at the affiliated hospital.

Results A 46 years old immunocompromised female present with a six week history of cognitive decline and one week history of fevers, nausea and vomiting. She was initially treated with a presumptive diagnosis of viral encephalitis with no significant improvement. MRI of the brain revealed extensive abnormalities in the medial temporal lobes bilaterally, basal ganglia, brainstem and superior cerebellum. Stereotactic biopsy of the right medial temporal lobe was inconclusive. Unfortunately, the patient deteriorated and died three weeks after presentation. Autopsy confirmed the diagnosis of lymphomatoid granulomatosis with EBV encoded RNA-in situ hybridisation (EBER-ISH) positive stains in multiple sites including the brain, heart, liver, kidneys and adrenal glands, but with no lung involvement.

Conclusions This case report illustrates the insidious nature of lymphomatoid granulomatosis and the clinical challenges it presents with diagnosis and prognosis. It often occurs in the setting of immunosuppression, as in this case. However, it is unique in that there was no pulmonary involvement despite other numerous extra-nodal sites being implicated. Greater recognition and research of this disease entity will provide significant advances in this area.