, with an equal distribution across genders and ethnicities.1 It is caused by mutations in the ECM1 gene2 on chromosome 1q21. This leads to the abnormal deposition of hyaline material in various tissues across different organ systems, with the classic manifestations known as the “string of pearls” sign and a hoarse cry or voice.
The rarity of lipoid proteinosis often leads to challenges in diagnosis. Particularly when deviating from the common association with consanguinity, the potential for de novo mutations or a broader genetic variability in disease expression is highlighted. Our patient presents with symptoms that are pathognomonic to LP with moniliform blepharosis and hoarseness of the voice, in addition to scarring of the extremities.
Other common clinical manifestations in patients with LP include cobblestoning of the mucosa; hyperkeratosis of the elbows, knees, and hands; and calcification of the amygdala with neuroimaging.3
Genetic testing that identifies a loss-of-function mutation in ECM1 offers diagnostic confirmation. Patients often need multidisciplinary care involving dermatology; ear, nose, throat; neurology; and genetics. Treatment of LP is mostly symptomatic with unsatisfactory resolution of cutaneous changes, with retinoids such as acitretin used as the first-line option and surgery as a consideration for laryngeal hyaline deposits.2 Although LP can affect different organ systems, patients tend to have a normal lifespan.
Dr. Donna Bilu Martin
LP is a rare disorder that dermatologists often learn about during textbook sessions or didactics in residency but do not see in practice for decades, or if ever. This case highlights the need to review the classic presentations of rare conditions.
This case and the photos were submitted by Ms. Chang, BS, Western University of Health Sciences, College of Osteopathic Medicine, Pomona, California; Dr. Connie Chang, Verdugo Dermatology, Glendale, California; and Dr. Yuchieh Kathryn Chang, MD Anderson Cancer Center, Houston, Texas. The column was edited by Donna Bilu Martin, MD.
Dr. Bilu Martin is a board-certified dermatologist in private practice at Premier Dermatology, MD, in Aventura, Florida. More diagnostic cases are available at mdedge.com/dermatology. To submit a case for possible publication, send an email to dermnews@mdedge.com.
References
1. Mcgrath JA. Handb Clin Neurol. 2015:132:317-22. doi: 10.1016/B978-0-444-62702-5.00023-8.
2. Hamada Tet al. Hum Mol Genet. 2002 Apr 1;11(7):833-40. doi: 10.1093/hmg/11.7.833.
3. Frenkel B et al. Clin Oral Investig. 2017 Sep;21(7):2245-51 doi: 10.1007/s00784-016-2017-7.