Evaluation of relationship retrospectively blood cyclosporin levels and acute graft versus host disease in early posttransplant period in patients with hematological malignancies who underwent allogeneic bone marrow transplant

Acute graft versus host disease (aGVHH) is the prime fatal complication. Combining cyclosporine (CsA) with methotrexate (MTX) is an immunosuppressive regimen frequently used as the standard regimen for graft-versus-host disease (GVHD) prophylaxis. Previous studies have shown that low blood CsA levels are associated with aGVHD. Our study aimed to examine the effects of blood CsA levels on the development of aGVHD in four different time intervals (0-14 days, 1st month, 1-2. months, 2-3. months) in the first 100 days and determine the target blood CsA level that will predict the development of aGVHD. In this study, patients with acute leukemia who underwent AHSCT (n=120, 64% AML, 36% ALL) between June 2011 and March 2021 were evaluated retrospectively. In all patients, GVHD prophylaxis was initiated as a combination of CsA+MTX. AGVHD developed in 34 (28%) patients who underwent AHSCT. The median day of aGVHD was 48. The findings showed that thirteen (38%) patients with aGVHD had high-stage (grade III-IV) aGVHD. The development of aGVHD was significantly higher in patients with blood CsA levels in the range of 100-200 µg/L between 0-14 days, and aGVHD was significantly higher in patients with blood CSA levels in the 200- 300 µg/L range at other time intervals. A blood CsA level of ≤274 µg/L in the 1-2 month period predicted the development of aGVHD with a significance vi value of p=0.002 with 77.3% sensitivity and 63% specificity. There was no significant relationship between aGVHD grades and blood CsA levels (p>0.05). In patients who developed aGVHD, a positive correlation was obtained regarding hypomagnesemia (r=0.650 correlation coefficient and p=0.009) with increased blood CsA levels over a 2-3 month. Acute renal injury was the most common side effect leading to the transition from CsA to another prophylaxis regimen at a rate of 53%. No correlation was found between blood CsA levels and CsA toxicities and toxicity grades. The agreed cut-off value of blood CsA level that can prevent the development of aGVHD in the literature has not been determined yet. Our study contributes to the literature as it is a single-center experience and can determine the blood CsA value that will predict the development of aGVHD.