[Sarcoidosis flare after autologous stem cell transplantation: An immune paradox?]

Sarcoidosis is a systemic granulomatous disorder of unknown cause. Apparition or flare of previously diagnosed sarcoidosis following hematopoietic stem cell transplantation (HSCT) has rarely been reported.

We report a 62-year-old woman who presented a radiological flare of sarcoidosis post-autologous stem cell transplantation for a POEMS syndrome. Imaging findings and lymph node histology, which revealed non-caseating granuloma, were consistent with the sarcoidosis diagnosis. The patient was asymptomatic and was kept free of treatment.

Sarcoidosis must be considered ahead of compatible clinicoradiological presentation occurring after HSCT. Sarcoidosis can mimic metastatic cancer or lymphatic relapse. Tissue biopsies and exclusion of differential diagnosis of granuloma diseases are warranted to confirm sarcoidosis diagnosis.