Neurotrophic keratitis in a patient with dihydroxypyrimidine dehydrogenase deficiency.

We describe a case of neurotrophic keratitis in association with dihydroxypyrimidine dehydrogenase (DHPD) deficiency. Ocular manifestations in patients with DHPD are rare and neurotrophic keratitis has never been reported before. A six-year-old boy who was a known case of DHPD deficiency and born of a consanguineous marriage presented to our clinic with non-healing corneal ulcers in both eyes. Reduced corneal sensations were detected and the patient was started on lubricating eye drops. The patient continues to be on lubricant eye drops and there has been no recurrence of the disease.

Unpredicted Severe Toxicity after 5-Fluorouracil Treatment due to Dihydropyrimidine Dehydrogenase Deficiency

Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme in the catabolism of 5-fluorouracil (5-FU). Thus, patients with a DPD deficiency are at risk of developing severe 5-FU-associated toxicity. A 37-year-old female with gastric cancer underwent a curative operation, followed by adjuvant chemotherapy consisting of 5-FU and epirubicin. After the first cycle of chemotherapy, the patient manifested grade 2 mucositis and febrile neutropenia, and when her treatment was subsequently continued with doxifluridine she developed severe mucositis and febrile neutropenia. A PCR study revealed that her DPD mRNA level was lower than that in a control group. Thus, when considering the routine use of 5-FU for the treatment of cancer patients, an analysis of DPD activity or screening for DPD mutations is warranted in confined patients who experience unpredicted severe toxicity after initial 5-FU administration, even though DPD deficiency is a rare metabolic defect.