Abstract
Although histopathological differences have been reported between acute graft-versus-host disease (aGVHD) rash and non-aGVHD rash in CD34(+)-selected peripheral blood stem cell transplantation (PBSCT) recipients, skin biopsy alone is usually insufficient to determine rash etiology. As such, distinguishing inflammatory non-aGVHD rashes, such as drug eruptions, from cutaneous aGVHD after CD34(+)-selected PBSCT remains challenging and relies on clinical presentation. This study aimed to identify etiologies of skin rash in the first year after CD34(+)-selected PBSCT and to assess whether laboratory serologic markers, transplant characteristics, and rash morphology and symptomatology aid in differentiation of cutaneous aGVHD rash versus non-aGVHD rash. We conducted a retrospective study of 243 adult patients who underwent CD34(+)-selected PBSCT at Memorial Sloan Kettering Cancer Center between 2008 and 2011. Among this cohort of transplant recipients, only 43 patients (17.7%) developed cutaneous aGVHD. A total of 152 patients (63%) were identified with rash within 1 year after PBSCT. The proportion of patients who experienced peripheral eosinophilia was not different between those with an aGVHD versus non-aGVHD rash (P ≥ .90), nor when stratified by CD34(+) selection method (Isolex, P = .70; CliniMACS, P≥ .90). The proportion of patients with pruritus was also not different between those with an aGVHD rash versus non-aGVHD rash (P= .20), or when stratified by CD34(+) selection modality (Isolex, P = .20; CliniMACS, P = .50). The most common cause of non-aGVHD rash among those with a clear etiology was drug (39% of Isolex; 26% of CliniMACS). Single drug culprits were identified in 51% of drug rashes. The most commonly reported offending agents included antibiotics, keratinocyte growth factor, chemotherapy, and recombinant glycosylated human IL-7.