Mohamed Hiba E, Hammad Israa I, Elamin Sarra, Elamin Elwaleed M, Ibrahim Anaheed I, El-Magzoub Abdul-Rahman A, Farragallah Ishraqa A, Elhasan Lamyaa A M, Elhasan Ahmed M
Faculty of medical laboratory sciences, Khartoum University, Khartoum, Sudan.
Ahmed Gasim Cardiac Surgery and Kidney Transplant Center,Khartoum, Sudan.
Arab J Nephrol Transplant. 2014 May;7(2):113-7.
C4d immunostaining of renal allograft biopsies is recommended for the diagnosis of antibody-mediated rejection (ABMR), but it was not available to us prior to June 2012. In June 2012, we were able to obtain anti-human C4d polyclonal antibody and decided to retrospectively evaluate archived kidney allograft biopsies at our center for C4d deposition.
Twenty-four paraffin blocks were available for this study. Immunostaining for C4d was performed using anti-human C4d polyclonal antibody by Immunohistochemistry. The score and pattern of C4d positivity were determined according to the Banff 2007 guidelines.
All grafts were from living related donors with negative CDC cross-match. The indications for biopsy were primary, acute and chronic graft dysfunction in 29.2%, 33.3% and 37.5% of patients respectively. Two biopsies revealed extensive necrosis rendering it difficult to interpret the result of C4d staining. Among the remaining 22 biopsies, C4d staining was categorized as negative in 40.9%, minimal in 13.6%, focal in 22.7% and diffuse in 22.7%. The prevalence of C4d positivity among biopsies taken due to primary, chronic and acute graft dysfunction was 71.4%, 44.4% and 12.5% respectively.
C4d positivity was common in biopsies taken from this group of kidney transplant recipients and its prevalence was particularly high among biopsies taken due to primary graft non-function. This indicates that missed ABMR is an important cause for kidney allograft dysfunction in our setting.
