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Neurodegeneration as the presenting symptom in 2 adults with xeroderma pigmentosum complementation group F
Niraj M Shanbhag1, Michael D Geschwind1, John J DiGiovanna1
1Department of Neurology (N.M.S., M.D.G.), University of California San Francisco, CA; Laboratory of Cancer Biology and Genetics (J.J.D., K.H.K.), Center for Cancer Research, National Cancer Institute, National Institutes of Health; NIH Undiagnosed Diseases Program (C.G., R.G., M.C.V.M., W.A.G., C.T.), National Human Genome Research Institute, National Institutes of Health, Bethesda, MD; and Department of Molecular Medicine (M.J.Y., E.A.W., L.J.N.), Center on Aging, The Scripps Research Institute, Jupiter, FL.
Objective:
To describe the features of 2 unrelated adults with xeroderma pigmentosum complementation group F (XP-F) ascertained in a neurology care setting.
Methods:
We report the clinical, imaging, molecular, and nucleotide excision repair (NER) capacity of 2 middle-aged women with progressive neurodegeneration ultimately diagnosed with XP-F.
Results:
Both patients presented with adult-onset progressive neurologic deterioration involving chorea, ataxia, hearing loss, cognitive deficits, profound brain atrophy, and a history of skin photosensitivity, skin freckling, and/or skin neoplasms. We identified compound heterozygous pathogenic mutations in ERCC4 and confirmed deficient NER capacity in skin fibroblasts from both patients.
Conclusions:
These cases illustrate the role of NER dysfunction in neurodegeneration and how adult-onset neurodegeneration could be the major symptom bringing XP-F patients to clinical attention. XP-F should be considered by neurologists in the differential diagnosis of patients with adult-onset progressive neurodegeneration accompanied by global brain atrophy and a history of heightened sun sensitivity, excessive freckling, and skin malignancies.
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