Erythropoietic protoporphyria (EPP) is an inherited photocutaneous disorder first described in 1961.1 The typical syndrome includes cutaneous photosensitivity, greatly increased erythrocyte and fecal protoporphyrin, and a variable but often marked increase in plasma protoporphyrin. The urine is normal.
Although the photosensitivity is clearly due to protoporphyrin, the site of formation of this porphyrin has been questioned. Initially it was suggested that the photosensitivity was associated with the high red cell porphyrin. However, in keeping with the other cutaneous porphyrias, increased porphyrin in the plasma was subsequently demonstrated.2,3 The possibility that the plasma porphyrin causes the photosensitivity and is synthesized at a nonerythropoietic site was suggested by Redeker and Bryan in 1964.4
The rate-limiting enzyme for porphyrin biosynthesis is aminolevulinic acid synthetase (ALA-S). Hepatic ALA-S is an inducible enzyme in patients with acute intermittent porphyria (AIP) and its rate of synthesis is reciprocal with carbohydrate or protein intake
Register and get free email Table of Contents alerts, saved searches, PowerPoint downloads, CME quizzes, and more
Subscribe for full-text access to content from 1998 forward and a host of useful features
Activate your current subscription (AMA members and current subscribers)
Purchase Online Access to this article for 24 hours
Country-Specific Mortality and Growth Failure in Infancy and Yound Children and
Association With Material Stature
Use interactive graphics and maps to view and sort country-specific infant and early
dhildhood mortality and growth failure data and their association with maternal
Thank you for submitting a comment on this article. It will be reviewed by JAMA Internal Medicine editors. You will be notified when your comment has been published. Comments should not exceed 500 words of text and 10 references.
Do not submit personal medical questions or information that could identify a specific patient, questions about a particular case, or general inquiries to an author. Only content that has not been published, posted, or submitted elsewhere should be submitted. By submitting this Comment, you and any coauthors transfer copyright to the journal if your Comment is posted.
* = Required Field
Disclosure of Any Conflicts of Interest*
Indicate all relevant conflicts of interest of each author below, including all relevant financial interests, activities, and relationships within the past 3 years including, but not limited to, employment, affiliation, grants or funding, consultancies, honoraria or payment, speakers’ bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued. If all authors have none, check "No potential conflicts or relevant financial interests" in the box below. Please also indicate any funding received in support of this work. The information will be posted with your response.
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Web of Science® Times Cited: 26
Customize your page view by dragging & repositioning the boxes below.
More Listings atJAMACareerCenter.com >
and access these and other features:
Enter your username and email address. We'll send you a link to reset your password.
Enter your username and email address. We'll send instructions on how to reset your password to the email address we have on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.