ABSTRACT
A 27-year-old male patient with a corneal scar secondary to herpetic keratitis in the right eye underwent penetrating keratoplasty (PK). At the 14th month of follow-up, latanoprost was started to treat high intraocular pressure which was refractory to treatment. On the 15th day of latanoprost use, allograft reaction (AR) developed. Insufficient clinical response despite intensive immunosuppressive therapy made us consider the possibility of recurrent herpetic keratouveitis secondary to steroid treatment. The dramatic reduction in the number of keratic precipitates with oral valacyclovir treatment confirmed this diagnosis. The graft remained clear 3 months after the AR treatment. Inflammation in eyes that had undergone PK jeopardizes the graft success by disrupting the immune privilege of anterior chamber. Considering the effects of prostaglandin analogues on blood-aqueous barrier, latanoprost use might have been related to allograft reaction in this case. Another remarkable characteristics of this case was the herpes simplex virus (HSV) reactivation secondary to AR therapy. For this reason, oral acyclovir prophylaxis together with AR therapy would improve graft success in cases with HSV history. (Turk J Ophthalmol 2012; 42: 150-3)