Hypomelanosis of Ito Workup
- Author: Manuel Valdebran, MD; Chief Editor: Dirk M Elston, MD more...
Only history taking and physical examination with special attention to the neurologic and ophthalmologic findings are necessary to detect abnormalities associated with hypomelanosis of Ito.
If genetic and/or chromosomal testing are considered, these should be coordinated with someone who is conducting research on this disease.
Perform imaging only as indicated by the features of the history and physical examination.
CT and/or MRI of head should be performed in those with neurologic symptoms.
Skeletal radiography should be performed in hypomelanosis of Ito patients with apparent bony abnormalities.
Perform EEG in hypomelanosis of Ito patients with seizure disorders.
Perform electromyelography (EMG) in those with hypotonia.
Histological findings include a decreased amount of melanin present in keratinocytes and melanocytes along the basal layer of the epidermis. Special stains such as Fontana-Masson are used to evaluate these changes. Ultrastructurally, melanocytes show decreased size and a reduction on the number of dendrites.
Pavone V, Signorelli SS, Praticò AD, Corsello G, Savasta S, Falsaperla R, et al. Total Hemi-overgrowth in Pigmentary Mosaicism of the (Hypomelanosis of) Ito Type: Eight Case Reports. Am J Med Genet. 2016 Mar. 95:e2705. [Medline].
Küster W, König A. Hypomelanosis of Ito: no entity, but a cutaneous sign of mosaicism. Am J Med Genet. 1999 Aug. 85:346-50. [Medline].
Molho-Pessach V, Schaffer JV. Blaschko lines and other patterns of cutaneous mosaicism. Clin Dermatol. 2011 Mar-Apr. 29:205-225. [Medline].
Ponti G, Pellacani G, Tomasi A, Percesepe A, Guarneri C, Guerra A, et al. Hypomelanosis of Ito with a trisomy 2 mosaicism: a case report. J Med Case Rep. 2014 Oct. 9:333. [Medline].
Girard C, Guillot B, Rivier F, Dalla Vale F, Bessis D. Trisomy 20 mosaicism revealed by pigmentary mosaicism of the Ito-type. Ann Dermatol Venereol. 2005 Feb. 132:151-3. [Medline].
Assogba K, Ferlazzo E, Striano P, Calarese T, Villeneuve N, Ivanov I, et al. Heterogeneous seizure manifestations in Hypomelanosis of Ito: report of four new cases and review of the literature. Neurol Sci. 2010 Feb. 31(1):9-16. [Medline].
Scott A, Micallef C, Hale SL, Watts P. Cortical visual impairment in hypomelanosis of Ito. J Pediatr Ophthalmol Strabismus. 2008 Jul-Aug. 45(4):240-1. [Medline].
Iype M, Iype T, Geetha S, Retnakumar J. Hypomelanosis of Ito with cerebral malformation. Indian J Pediatr. 2007 Nov. 74(11):1044-5. [Medline].
Vergine G, Mencarelli F, Diomedi-Camassei F, et al. Glomerulocystic kidney disease in hypomelanosis of Ito. Pediatr Nephrol. 2008 Jul. 23(7):1183-7. [Medline].
Calonje E, Brenn T, Lazar AJ, McKee PH. Disorders of Pigmentation. Elsevier/Saunders. McKee's Pathology of the Skin: With Clinical Correlations. 4th ed. Philadelphia, Pa: Elsevier Saunders; 2011. 912.
Online Mendelian Inheritance in Man (OMIM). HYPOMELANOSIS OF ITO; HMI. Available at http://omim.org/entry/300337. Accessed: August 11, 2014.