In our evaluations, carried out in patients with early GVHD and mild-moderate dry eye, we found that the positive expression of MMP-9 was significantly more frequent in GVHD than in DED; moreover, the ROC curve analysis demonstrated high sensitivity and specificity of the positivity of the InflammaDry test, also considering this mild stage of GVHD. The gene discussed is MMP9; the disease is graft versus host disease.