Pyridoxine-Induced Photosensitivity and Hypophosphatasia

We describe a case of photosensitivity due to pyridoxine hydrochloride (vitamin B6) in a heterozygote of hypophosphatasia. Photopatch tests using pyridoxine hydrochloride and pyridoxal 5′-phosphate, compounds referred to as vitamin B6, with ultraviolet light A irradiation were positive. Laboratory examination showed low serum alkaline phosphatase. Tissue-nonspecific alkaline phosphatase exon amplification from DNA of the patient’s lymphocytes detected deletion 1154–1156 hypophosphatasia mutation, indicating that this patient was diagnosed to be a heterozygote of hypophosphatasia. The seric pyridoxal 5′-phosphate level of this patient with hypophosphatasia was higher than in normals. Furthermore, after oral administration of vitamin B6 this level increased greatly and long-lastingly, and this might be related to the low level of alkaline phosphatase in this patient. Photosensitivity in this patient may have been caused by abnormal metabolism of vitamin B6 under the hypophosphatic condition.

[1]  N. Araki,et al.  Photosensitive dermatitis caused by pyridoxine hydrochloride. , 1998, Journal of the American Academy of Dermatology.

[2]  J. Manson,et al.  Folate and vitamin B6 from diet and supplements in relation to risk of coronary heart disease among women. , 1998, JAMA.

[3]  T. Reynolds,et al.  Relationship between serum alkaline phosphatase and pyridoxal-5'-phosphate levels in hypophosphatasia. , 1998, Clinical science.

[4]  Seiji Sato,et al.  Genetic analysis of hypophosphatasia , 1997, Acta paediatrica Japonica : Overseas edition.

[5]  M. Goseki‐Sone,et al.  Detection of deletion 1154-1156 hypophosphatasia mutation using TNSALP exon amplification. , 1997, Genomics.

[6]  S. Coburn Modeling vitamin B6 metabolism. , 1996, Advances in food and nutrition research.

[7]  S. Shimizu,et al.  Photoallergic Drug Eruption Due to Pyridoxine Hydrochloride , 1996, The Journal of dermatology.

[8]  A. Kawada,et al.  Photosensitivity from pyridoxine hydrochloride (vitamin B6). , 1996, Journal of the American Academy of Dermatology.

[9]  K. E. Newhouse,et al.  Review and Notes: Pharmacology: Conn's Current Therapy: Latest Approved Methods of Treatment for the Practicing Physician , 1996, Annals of Internal Medicine.

[10]  K. Yoshikawa,et al.  Pyridoxine toxicity to cultured fibroblasts caused by near-ultraviolet light. , 1993, The Journal of investigative dermatology.

[11]  K. Tadera,et al.  Isocratic paired-ion high-performance liquid chromatographic method to determine B6 vitamers and pyridoxine glucoside in foods , 1991 .

[12]  H. Harris,et al.  Structure of the human liver/bone/kidney alkaline phosphatase gene. , 1988, The Journal of biological chemistry.

[13]  C. Slaughter,et al.  Isolation and characterization of a cDNA encoding a human liver/bone/kidney-type alkaline phosphatase. , 1986, Proceedings of the National Academy of Sciences of the United States of America.

[14]  S. Coburn,et al.  Markedly increased circulating pyridoxal-5'-phosphate levels in hypophosphatasia. Alkaline phosphatase acts in vitamin B6 metabolism. , 1985, The Journal of clinical investigation.

[15]  R. Baer Cutaneous skin changes probably due to pyridoxine abuse. , 1984, Journal of the American Academy of Dermatology.

[16]  H. Wada,et al.  The enzymatic oxidation of pyridoxine and pyridoxamine phosphates. , 1961, The Journal of biological chemistry.