Patient 2:
A thirteen-year-old girl (born to consanguineous parents) was diagnosed as leaky SCID due to Artemis mutation at 4 years, after multiple hospitalizations due to recurrent fever, diarrhea and bronchitis. She was referred to our centre for HSCT but unfortunately, she had conglomerate cervical lymphadenopathies on the admission. Excisional biopsy revealed marginal zone B cell lymphoma. She received 13 doses of Rituximab treatment leading to remission. Since a matched donor was not available in the family, she transplanted from an HLA 10/10 matched unrelated donor (MUD) following an RIC regimen consisting of Rituximab (375 mg/m2), Treosulfan (42g/m2), Fludarabine (150mg/m2) and ATG (40mg/kg) at age of fourteen. CSA and MMF were preferred for GvHD prophylaxis. On post-transplant 21st day, severe diarrhea (1900 cc/day) and subsequently faecal occult blood occurred. A Grade IV GvHD was revealed by endoscopic and colonoscopic biopsies. Methylprednisolone (2mg/kg/day) and oral budesonide treatments were started. However, diarrhea was persistent and didn’t respond to treatment, so CSA was switched to tacrolimus, infusions(x3) of mesenchymal stem cells and Tocilizumab (x1) were added to treatment respectively. Despite of all these intensive treatments, diarrhea persisted, so we decided to use AAT. After two doses of AAT, diarrhea started to resolve and the steroid tapering schedule was started. During steroid taper, after five doses of AAT, moderate transaminase elevation (AST: 241 IU/ml, ALT: 413 IU/ml) was detected as a possible side effect of the drug. We discontinued the treatment for a week until normal transaminase levels were achieved. During this period, a flare-up in diarrhea occurred and necessitated an additional dose of Tocilizumab. Subsequently, we completed AAT to 8 doses but even total 5 doses of Tocilizumab could resolve her GvHD on the 130th day. (Table 2)