Normal-looking skin in oncohaematological patients after allogenic bone marrow transplantation is not normal

Background Graft-versus-host-disease (GvHD) occurs in one-third or even half of bone marrow transplant (BMT) patients, involving three major target organs: gut, liver and skin. Objectives The histopathological and immunohistochemical features of normal-looking skin in oncohaematological patients on day 100 after BMT were studied to find a possible relationship between the histopathological findings and clinical variables (history or clinical evidence of GvHD, previous therapeutic regimens or infections). Methods Fifty-one Caucasian oncohaematological patients, who had had an allogenic BMT, had a biopsy taken from normal-looking skin in nonsun-exposed areas (buttocks or the lumbar region), around the 100th day after BMT. The histology was studied, and the influence of clinical variables on the development of every different histopathological pattern was evaluated through statistical analysis. Results Histopathological analysis based on morphological criteria revealed the presence of three different patterns: a postinflammatory pattern (45%), changes similar to grade I and II of GvHD (31%) and no significant changes (24%). Statistical analysis revealed that only the presence of peaks of cytomegalovirus (CMV) antigen in the blood within 100 days from BMT was significantly associated with the pattern of GvHD-like changes. Conclusions Normal-looking skin in 76% of BMT patients is not necessarily histologically normal. The pattern with more prominent changes, the GvHD-like pattern, has been found to be associated with a more frequent history of CMV antigen in the blood within 100 days from BMT.