A clinical study was made of 29 cases of erythropoietic protoporphyria in 14 families. There were 14 female and 15 male patients. The disease set in during early infancy. In 51% of the cases, there were mild systemic symptoms. The clinical appearances were similar to those described by others, except that only four patients (14%) had vesicles and four (14%) had a petechial rash. Scarring was, in most cases, a prominent feature. Thirteen patients (45%) noticed abatement of the disease with advancing age. Five patients (17%) had a marked subsidence of symptoms during pregnancy, but there was no change in the protoporphyrin level. One patient had no lunulae and eight patients (28%) had acute nail changes during the skin attack.
Protoporphyrin in the erythrocytes was elevated 10 to 100 times beyond the normal level. Results of liver function tests were normal in all patients, but liver biopsy, performed in one patient, disclosed a high content of porphyrin in the liver.
Schmidt H, Snitker G, Thomsen K, Lintrup J. Erythropoietic ProtoporphyriaA Clinical Study Based on 29 Cases in 14 Families. Arch Dermatol. 1974;110(1):58-64. doi:10.1001/archderm.1974.01630070026004