Poh-Fitzpatrick M B
Department of Dermatology, Columbia University College of Physicians and Surgeons, St. Luke's-Roosevelt Hospital Center, New York, NY 10019, USA.
J Am Acad Dermatol. 1997 Jan;36(1):40-3. doi: 10.1016/s0190-9622(97)70323-2.
Women with erythropoietic protoporphyria (EPP) have reported increased sunlight tolerance during pregnancy. Review of clinical information in an existing database for an EPP population study found five women who had six pregnancies while enrolled. All had experienced attenuated photosensitivity during gestation.
Our purpose was to gain insight into whether altered porphyrin metabolism during pregnancy might explain this phenomenon.
Erythrocyte protoporphyrin levels obtained for these women during six periods of gestation were compared with data accumulated over the course of several years during nongestational periods.
Erythrocyte porphyrin levels were lower during pregnancy. The differences of the means for values obtained during nongestational periods versus values obtained during pregnancy for each woman were found to reach or approach significance (p < 0.05) by a paired t test when analyzed without regard for seasonality (p = 0.042) or when adjusted for possible seasonal effects of sunlight on erythrocyte porphyrin levels by separation into data sets for low sunlight months (October-April) (p = 0.039) or high sunlight months (May-September) (p = 0.057).
These observations suggest that a beneficial physiologic effect of pregnancy in patients with EPP may be a lower circulating erythrocyte protoporphyrin burden that leads to reduced photosensitivity.
患有红细胞生成性原卟啉症（EPP）的女性报告称，孕期对阳光的耐受性增强。对一个用于EPP人群研究的现有数据库中的临床信息进行回顾时，发现有五名女性在入组期间怀孕了六次。所有这些女性在妊娠期都经历了光敏性减弱的情况。
我们的目的是深入了解孕期卟啉代谢的改变是否可以解释这一现象。
将这些女性在六个妊娠期获得的红细胞原卟啉水平与她们在非妊娠期数年期间积累的数据进行比较。
孕期红细胞卟啉水平较低。在不考虑季节性（p = 0.042）进行分析时，或通过将数据分为阳光较少月份（10月至4月）（p = 0.039）或阳光较多月份（5月至9月）（p = 0.057）来调整阳光对红细胞卟啉水平可能的季节性影响时，通过配对t检验发现，每位女性非妊娠期获得的值与孕期获得的值的均值差异达到或接近显著水平（p < 0.05）。
这些观察结果表明，孕期对EPP患者的有益生理作用可能是降低循环红细胞原卟啉负荷，从而导致光敏性降低。
