Neutrophil margination a a poible mechanim for verteporfin infuion-aociated pain

Purpoe To invetigate the change in abolute neutrophil count in patient with and without pain after verteporfin infuion. Deign Experimental tudy. Method The abolute neutrophil count were obtained from the blood ample taken at the beginning of infuion and after the end of verteporfin infuion. Reult Four patient in whom verteporfin infuion-related pain developed had a decreae in the abolute neutrophil count from a preinfuion mean of 4,589/mm3 to a potinfuion mean of 1,688/mm3 while they had pain, a compared with preinfuion and potinfuion count of 4,912/mm3 and 4,111/mm3, repectively, in five control patient having no pain, a difference in proportion that wa ignificant (P = .027). Concluion Patient in thi tudy with verteporfin infuion-aociated pain developed neutropenia during infuion, mot likely from drug-induced neutrophil margination. It i poible that medication preventing the tranient neutropenia may help avert verteporfin infuion-aociated pain.