Characterization of Signs for Rejection of Transplanted Kidneys in Sudanese Patients using Ultrasonography

ABSTRACT

A retrospective study was conducted in Khartoum State from July 2015 to April 2017. A total of 115 cases of transplanted kidneys were retrospectively analyzed. There were missing cases. A designed data collection sheet was used to collect the sonographic findings, clinical and demographic data. The renal cortex, corticomedullary differentiation and ratio (CMD & CMR) and graft size were evaluated and analyzed using software statistical program (SPSS).

Assessment of morphology and hemodynamics of transplanted kidneys provides informative data on underlying pathological processes that involve the transplanted kidneys. Identification of these morphological changes is useful to predict the rejection as early as possible. Objective: to predict signs of rejection by evaluating the morphological and hemodynamic changes; Doppler resistive index (RI) corticomedullary differentiation, corticomedullary ratio, cortical thickness and graft size of transplanted kidneys in Sudanese using ultrasonography.

The results of this study the most of the patients were workers (29.6%), employee 27.8% and housewives 20%. Sonographic evaluation of transplanted kidneys showed the CMD was disturbed in 20.9%, lost 4.3%. The CMR was increased by 7.8% and decreased by 13%. The graft cortex was thin in 9.6% of the cases, thick in 0.9% and normal in 87.6%. There was no significant correlation of Doppler resistive index with CMD, CMR, cortical thickness and graft size (p-values = 0.38, 0.11 and 0.37 respectively). The mean RI was 0.67, creatinine was 3.45 mg/dL and blood urea was 76.04mg/dL. The study revealed that rejection was considered to be highly likely when RI ≥.9, Rejection likely when RI = 0.80-0.89, indeterminate when RI= 0.70-0.79 and rejection was unlikely when RI < 0.70. The RI was significantly associated with gender and revealed negative significant correlation with echogenicity of parenchyma of the

graft. However, the RI was not statistically significantly correlated with the graft size, CMD, CMR, cortical thickness, serum creatinine and blood urea (p-values= 0.19, 0.10, 0.50, 0.42, 0.91 and 0.47 respectively). But it elevated in grafts with increased CMR, echogenicity and disturbed CMD. And this is clinically significant since it reflects the intrarenal pathological processes in the grafts.

The present study concluded that in Sudanese patients, there were considerable morphological and hemodynamic changes involving the graft. The Doppler resistive index and duration of transplantation have no statistical correlation with morphological changes in the graft. However, the morphological appearance was attributed to pathological changes which were landmarks to predict the rejection. The RI was significantly different between males and females and it significantly decreased in echogenic grafts. The morphological changes and elevated RI were important signs to predict rejection of the grafts.