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Hypomelanosis of Ito Workup

  • Author: Manuel Valdebran, MD; Chief Editor: Dirk M Elston, MD  more...
Updated: Apr 18, 2016

Laboratory Studies

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.


Imaging Studies

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.


Other Tests

Perform EEG in hypomelanosis of Ito patients with seizure disorders.

Perform electromyelography (EMG) in those with hypotonia.


Histologic Findings

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.[10]

Contributor Information and Disclosures

Manuel Valdebran, MD Visiting Dermatopathology Fellow, University of California, San Francisco, School of Medicine

Manuel Valdebran, MD is a member of the following medical societies: International Dermoscopy Society, Medical Dermatology Society, Society for Pediatric Dermatology

Disclosure: Nothing to disclose.

Specialty Editor Board

Michael J Wells, MD, FAAD Associate Professor, Department of Dermatology, Texas Tech University Health Sciences Center, Paul L Foster School of Medicine

Michael J Wells, MD, FAAD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Dermatology, American Medical Association, Texas Medical Association

Disclosure: Nothing to disclose.

Christen M Mowad, MD Professor, Department of Dermatology, Geisinger Medical Center

Christen M Mowad, MD is a member of the following medical societies: Alpha Omega Alpha, Noah Worcester Dermatological Society, Pennsylvania Academy of Dermatology, American Academy of Dermatology, Phi Beta Kappa

Disclosure: Nothing to disclose.

Chief Editor

Dirk M Elston, MD Professor and Chairman, Department of Dermatology and Dermatologic Surgery, Medical University of South Carolina College of Medicine

Dirk M Elston, MD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

Additional Contributors

John Louis Ratz, MD, MBA Private Practice Dermatologist, Mohs Surgeon, Tampa, Florida

John Louis Ratz, MD, MBA is a member of the following medical societies: American Academy of Dermatology, American College of Mohs Surgery, American College of Physicians, American Society for Dermatologic Surgery, American Society for Laser Medicine and Surgery, International Society for Dermatologic Surgery, Southern Medical Association

Disclosure: Nothing to disclose.

Sungnack Lee, MD Vice President of Medical Affairs, Professor, Department of Dermatology, Ajou University School of Medicine, Korea

Sungnack Lee, MD is a member of the following medical societies: American Academy of Dermatology

Disclosure: Nothing to disclose.

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  8. Iype M, Iype T, Geetha S, Retnakumar J. Hypomelanosis of Ito with cerebral malformation. Indian J Pediatr. 2007 Nov. 74(11):1044-5. [Medline].

  9. 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].

  10. 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.

  11. Online Mendelian Inheritance in Man (OMIM). HYPOMELANOSIS OF ITO; HMI. Available at Accessed: August 11, 2014.

Hypomelanosis of Ito on the arm.
Hypomelanosis of Ito highlighted with a Wood lamp.
Hypomelanosis of Ito on the torso.
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