title: Intermediate dose 5-fluorouracil-induced encephalopathy.
abstract: As an acute neurotoxicity, high dose 5-fluorouracil (5-FU)-induced encephalopathy is well-known, but encephalopathy associated with lower dose is rarely reported. Here, we report a case of a male with anal cancer who was treated with 5-FU 1000 mg/m(2), continuous infusion for 5 days q4 weeks. At the second and the fourth cycles of chemotherapy, sudden confusion, cognitive dysfunction and disorientation occurred during 5-FU infusion. They were accompanied by hyperammonemia in the absence of focal neurological deficits or structural abnormalities. These symptoms completely disappeared and the serum ammonia level returned to normal after discontinuation of 5-FU and conservative care. In order to investigate a possible deficit of dihydropyrimidine dehydrogenase (DPD), we checked its mRNA level before and after treatment using real-time PCR. The patient's pre-treatment level was 80% compared with reference group, and it was elevated up to 187% of initial after 5-FU treatment, implying that that his encephalopathy may be 5-FU catabolite type rather than DPD deficiency. In conclusion, we report that encephalopathy can develop even with the dose of 5-FU lower than ever reported, and it should be considered as a differential diagnosis for proper management.
authors.affiliation: Department of Internal Medicine, Yonsei Cancer Center, Seoul, Korea.
authors.forename: Yeon-A
authors.initials: YA
authors.lastname: Kim
authors.forename: Hyun Cheol
authors.initials: HC
authors.lastname: Chung
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Choi
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Rha
authors.forename: Jin Sil
authors.initials: JS
authors.lastname: Seong
authors.forename: Hei-Cheul
authors.initials: HC
authors.lastname: Jeung
mesh_terms: D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000009:adverse effects*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use; D001005:Anus Neoplasms / Q000188:drug therapy / Q000473:pathology; D002945:Cisplatin / Q000008:administration & dosage; D003937:Diagnosis, Differential; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005472:Fluorouracil / Q000009:adverse effects*; D006801:Humans; D022124:Hyperammonemia / Q000150:complications; D007262:Infusions, Intravenous; D008297:Male; D009361:Neoplasm Invasiveness; D020258:Neurotoxicity Syndromes / Q000175:diagnosis / Q000209:etiology*
chemical_list: D000964:Antimetabolites, Antineoplastic; D002945:Cisplatin; D005472:Fluorouracil