1992: Consensus Conference

Individuals affected by PXE generally show a great deal of variety in the severity of symptoms, even between family members. On June 10, 1992, 40 prominent researchers and physicians working on PXE attended a consensus conference at the Jefferson Memorial College in Philadelphia, Pennsylvania to discuss and characterize the criteria used to diagnosis PXE as well as further directions for research on PXE. Dr. Jouni Uitto, of the PXE International Research Consortium, chaired the conference. The featured speaker of the conference was Dr. Victor McKusick of the Johns Hopkins School of Medicine who presented on the clinical and genetic issues associated with the diagnosis and inheritance of PXE.

Other presenters and topics discussed included:

“Classification of PXE Into Clinical Subtypes”
Dr. F. Michael Pope, Dermatology Research Group, Harrow, Middlesex, UK

“Dominant PXE is an Underrepresented Disorder”
Dr. Mark G. Lebwohl, Mt. Sinai School of Medicine, New York, NY

“Experimental Models of Calcification of Elastic Fibers in PXE”
Dr. Lis Danielsen, Bisbjerg Hospital, Copenhagen, Denmark

“Evolution of the PXE Phenotype”
Dr. Kenneth Neldner, Texas Tech University Health Science Center, Lubbock, TX

“Specific Recessive Forms of PXE”
Dr. Anne de Paepe, University Hospital, Gent, Belgium

“The Candidate Gene Approach to PXE”
Dr. Charles D. Boyd, UMDNJ-RWJ Medical School, New Brunswick, NJ

“Linkage Studies in PXE Families”
Dr. Angela M. Christiano, Jefferson Medical College, Philadelphia, PA

“Fibrillin Expression in PXE Fibroblast Cultures”
Dr. Maurice Godfrey, University of Nebraska, Omaha, NE

“Fibrillin Mutations in the Marfan Syndrome – Lessons for PXE”
Dr. Harry C. Dietz, John Hopkins University School of Medicine, Baltimore, MD

“Discussion on the Establishment of a Centralized PXE Database and Update on NAPE”
Ms. Carol Daugherty, Texas Tech University Health Sciences Center, Lubbock, TX

During the conference, both physicians and researchers collaborated to define both major and minor diagnostic criteria for the diagnosis of PXE (Table I).

Table 1: Criteria for the diagnosis of PXE

Major Criteria:

1. Characteristic skin involvement (yellow cobblestone lesion in flexural locations)
2. Characteristic histopathologic features of lesional skin (elastic tissue and calcium on von Kossa stains)
3. Characteristic ocular disease (angioid streaks, peau d´orange, or maculopathy) in adults older than 20 years of age

Minor Criteria:

1. Characteristic histopathologic features of nonlesional skin (elastic tissue and calcium on von Kossa stains)
2. Family history of PXE in first-degree relatives
3. Using these major and minor criteria, a classification system was developed to sub-classify cases of PXE into Category I or II PXE (Table 2)

Table 2: Classification of PXE

For more information, please see the following published articles:

Christiano AM, Lebwohl MG, Boyd CD, Uitto J: Workshop on pseudoxanthoma elasticum: molecular biology and pathology of the elastic fibers. Jefferson Medical College, Philadelphia, Pennsylvania, June 10, 1992. J Invest Dermatol. 1992 Nov;99(5):660-3 Free article at Journal Website

Lebwohl M, Neldner K, Pope FM, De Paepe A, Christiano AM, Boyd CD, Uitto J, McKusick VA: Classification of pseudoxanthoma elasticum: report of a consensus conference. J Am Acad Dermatol. 1994 Jan;30(1):103-7.