Objective: A 26-year-old man with a history of Crohn's
disease, treated with azathioprine since 2 years, presented
an Epstein-Barr virus (EBV) primo-infection and exacerbation
of digestive symptoms.
Method: An ileo-colectomy was performed, which showed
a fatal EBV lymphoproliferation disorder along with a
haemophagocytic syndrome. EBV DNA load in the
peripheral blood persisted to be high loaded during
hospitalisation (479,000 copies per milliliter) despite triple
antiviral treatment.
Results: Autopsy revealed a systemic lymphoproliferation
involving lymph nodes, gastrointestinal mucosa and
solid viscera (heart, kidney, lungs, prostate, brain). This
was compounded of a population of large polymorphic B
cell, hypertrophic macrophages and T lymphocytes,
associated to haemophagocytosis. These massive infiltrations
mimicked macroscopically as ulcers in the intestinal
mucosa and ranged from polymorphic with plasmocytic
differentiation to monomorphic large cells. Autopsy
results confirmed the absence of Crohn's disease reactivation.
The EBV infection was observed in all organs
within the large images of the B cell lymphoproliferations.
Further postmortem investigations revealed a
deficit of the azathioprine's metabolisation enzyme
thiopurine methyltransferase (TPMT).
Conclusion: We report and discuss herein the observations
of a complete autopsy case along with the postmortem
identification of the EBV infection type and TPMT
mutation in a patient treated by azathioprine for Crohn's
disease. Autopsy findings and further investigations helped
explain the complicate clinical evolution and the fatal issue
of the patient.