Pityriasis alba

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Pityriasis alba
Classification and external resources
ICD-10 L30.5 (ILDS L30.590)
ICD-9 696.5
DiseasesDB 31121
MedlinePlus 001463
eMedicine ped/1813 derm/333 emerg/425

Pityriasis alba is a common skin condition mostly occurring in children and usually seen as dry, fine-scaled, pale patches on the face. It is self-limiting and usually only requires use of moisturizer creams.

The condition is so named for the fine scaly appearance initially present (pityriasis) and the pallor of the patches that develop (while "alba" is Latin for white, the patches in this condition are not totally depigmented).[1]

Etiology[edit]

Any dermatitis may heal leaving pale skin, as may excessive use of corticosteroid creams used to treat episodes of eczema. The hypopigmentation is due to both reduced activity of melanocytes with fewer and smaller melanosomes.[2][3]

The condition is most often seen in children between the ages of 3 and 16 years and is more common in males than females.[4] It may occur more frequently in lighter-skinned patients, but is more apparent in those with darker complexions.[5]

Up to a third of US school children may at some stage have this condition. Single-point prevalence studies from India have shown variable rates from 8.4%,[6] to 31%.[7] Other studies have shown prevalence rates in Brazil of 9.9%,[8] Egypt 13.49%,[9] Romania 5.1%,[10] Turkey 12% where higher rates were seen in those with poor socioeconomic conditions,[11] and just 1% in school children in Hong Kong.[12]

Symptoms and signs[edit]

The dry scaling appearance is most noticeable during the winter as a result of dry air inside people's homes. During the summer, tanning of the surrounding normal skin makes the pale patches of pityriasis alba more prominent.

Individual lesions develop through 3 stages and sometimes are itchy:

  1. Raised and red - although the redness is often mild and not noticed by parents
  2. Raised and pale
  3. Smooth flat pale patches

Lesions are round or oval raised or flat, of 0.5–2 cm in size although may be larger if they occur on the body (up to 4 cm), and usually number from 4 or 5 to over 20. The patches are dry with very fine scales. They most commonly occur on the face (cheeks), but in 20% appear also on the upper arms, neck, or shoulders.

The diagnostic differential should consider tinea and vitiligo amongst other causative factors.[13]

Treatment[edit]

No treatment is required and the patches in time will settle.[14] The redness, scale and itch if present may be managed with simple emollients and sometimes hydrocortisone, a weak steroid, is also used.[15]

As the patches of pityriasis alba do not darken normally in sunlight, effective sun protection helps minimise the discrepancy in colouration against the surrounding normal skin. Cosmetic camouflage may be required.

Tacrolimus has been reported as speeding resolution.[16]

In exceptionally severe cases PUVA therapy may be considered.[17]

Prognosis[edit]

The patches of pityriasis alba may last from 1 month to about one year, but commonly on the face last a year.

See also[edit]

References[edit]

  1. ^ a b Pinto FJ, Bolognia JL (1991). "Disorders of hypopigmentation in children". Pediatr. Clin. North Am. 38 (4): 991–1017. PMID 1870914. 
  2. ^ Vargas-Ocampo F (1993). "Pityriasis alba: a histologic study". Int. J. Dermatol. 32 (12): 870–873. doi:10.1111/j.1365-4362.1993.tb01401.x. PMID 8125687. 
  3. ^ Freedberg, et al. (2003). Fitzpatrick's Dermatology in General Medicine. (6th ed.). McGraw-Hill. ISBN 0-07-138076-0.
  4. ^ Blessmann Weber M, Sponchiado de Avila LG, Albaneze R, Magalhães de Oliveira OL, Sudhaus BD, Cestari TF (2002). "Pityriasis alba: a study of pathogenic factors". Journal of the European Academy of Dermatology and Venereology : JEADV 16 (5): 463–468. doi:10.1046/j.1468-3083.2002.00494.x. PMID 12428838. 
  5. ^ Laude TA (1995). "Approach to dermatologic disorders in black children". Seminars in dermatology 14 (1): 15–20. doi:10.1016/S1085-5629(05)80034-3. PMID 7742234. 
  6. ^ Dogra S, Kumar B (2003). "Epidemiology of skin diseases in school children: a study from northern India". Pediatric dermatology 20 (6): 470–473. doi:10.1111/j.1525-1470.2003.20602.x. PMID 14651562. 
  7. ^ Faye O, N'Diaye HT, Keita S, Traoré AK, Hay RJ, Mahé A (2005). "High prevalence of non-leprotic hypochromic patches among children in a rural area of Mali, West Africa". Leprosy review 76 (2): 144–6. PMID 16038247. 
  8. ^ Bechelli LM, Haddad N, Pimenta WP, Pagnano PM, Melchior E, Fregnan RC, Zanin LC, Arenas A (1981). "Epidemiological survey of skin diseases in schoolchildren living in the Purus Valley (Acre State, Amazonia, Brazil)". Dermatologica 163 (1): 78–93. doi:10.1159/000250144. PMID 7274519. 
  9. ^ Abdel-Hafez K, Abdel-Aty MA, Hofny ER (2003). "Prevalence of skin diseases in rural areas of Assiut Governorate, Upper Egypt". Int. J. Dermatol. 42 (11): 887–892. doi:10.1046/j.1365-4362.2003.01936.x. PMID 14636205. 
  10. ^ Popescu R, Popescu CM, Williams HC, Forsea D (1999). "The prevalence of skin conditions in Romanian school children". Br. J. Dermatol. 140 (5): 891–896. doi:10.1046/j.1365-2133.1999.02821.x. PMID 10354028. 
  11. ^ Inanir I, Sahin MT, Gündüz K, Dinç G, Türel A, Oztürkcan S (2002). "Prevalence of skin conditions in primary school children in Turkey: differences based on socioeconomic factors". Pediatric dermatology 19 (4): 307–311. doi:10.1046/j.1525-1470.2002.00087.x. PMID 12220273. 
  12. ^ Fung WK, Lo KK (2000). "Prevalence of skin disease among school children and adolescents in a Student Health Service Center in Hong Kong". Pediatric dermatology 17 (6): 440–446. doi:10.1046/j.1525-1470.2000.01841.x. PMID 11123774. 
  13. ^ http://emedicine.medscape.com/article/762656-overview
  14. ^ Lin RL, Janniger CK (2005). "Pityriasis alba". Cutis; cutaneous medicine for the practitioner 76 (1): 21–4. PMID 16144284. 
  15. ^ Harper J (1988). "Topical corticosteroids for skin disorders in infants and children". Drugs. 36 Suppl 5: 34–7. doi:10.2165/00003495-198800365-00007. PMID 2978289. 
  16. ^ Rigopoulos D, Gregoriou S, Charissi C, Kontochristopoulos G, Kalogeromitros D, Georgala S (2006). "Tacrolimus ointment 0.1% in pityriasis alba: an open-label, randomized, placebo-controlled study". Br. J. Dermatol. 155 (1): 152–155. doi:10.1111/j.1365-2133.2006.07181.x. PMID 16792767. 
  17. ^ Di Lernia V, Ricci C (2005). "Progressive and extensive hypomelanosis and extensive pityriasis alba: same disease, different names?". Journal of the European Academy of Dermatology and Venereology : JEADV 19 (3): 370–372. doi:10.1111/j.1468-3083.2004.01170.x. PMID 15857470.