Abstract Primary renal involvement by T lymphoblasts is rare among adults with T acute lymphoblastic leukaemia. We report a 28‐year‐old man presenting with acute renal failure due to infiltration by T lymphoblasts and his response to paediatric‐inspired modified BFM‐90 protocol. The patient achieved an initial complete remission (CR) but developed central nervous system relapse. He achieved CR2 with cranial irradiation and intrathecal chemotherapy. He underwent a haploidentical transplant in CR2 and remains in remission post‐transplant day 330. An early kidney biopsy helped confirm the diagnosis. Such presentations remain responsive to modified BFM‐90. An early allotransplant in CR2 remains the standard of care.
