Juvenile Atopic Dermatitis & Pityriasis Alba & Hair Loss

My 13 year old daughter has been experiencing chronic dermatitis, and what appears to be pityriasis alba on numerous parts of her body (neck, arms, legs).  She also has some sort of scalp problem that is very scaly and flaky and she is losing a large amount of hair daily.  We live in the Caribbean (moved here a little over a year ago).  We have two cats (indoor) and a dog (outdoor).  Looking for help as to what is going on with her hair loss and a solution to the skin issues.  We have been to a dermatologist on island several times, but no relief to her skin issues.  Should she see an allergist and/or a dermatologist?  

[Dr_Aparna]

Hi,
Seborrhoeic eczema (also Seborrheic dermatitis ) is a skin disorder affecting the scalp, face, and trunk causing scaly, flaky, itchy, red skin. The widely present yeast, Malassezia furfur (formerly known as Pityrosporum ovale), is involved as well as genetic, environmental, hormonal, and immune-system factors.
In children, excessive vitamin A intake can cause seborrhoeic dermatitis. Lack of biotin,pyridoxine (vitamin B6 and riboflavin (vitamin B2 may also be a cause.
Those afflicted with seborrhoeic dermatitis have an unfavourable epidermic response to the infection, with the skin becoming inflamed and flaking.
Side effects to inflammation may include temporary hair loss. If severe outbreaks go untreated for long periods of time, permanent hair loss may result due to damaged hair follicles.
Expect two to six months before hair growth may resume.Among dermatologist recommended treatments are shampoos containing coal tar, ciclopiroxolamine ketoconazole, selenium sulfide, or zinc pyrithione.
ref:http://en.wikipedia.org/wiki/Seborrhoeic_dermatitis
Many different conditions can produce new white patches in children;PITYRIASIS ALBA AND tINEA VERSICOLOR ARE TWO OF THE MOST COMMON.
In pityriasis alba,  children develop uneven, round or oval patches after sun exposure. The patches are dry with very fine scales. Varying from 1 to 2 inches in diameter, they are most common on the face (cheeks), neck, upper trunk, and upper arms.
These are completely benign, similar to a mild form of eczema. They are most common in children with dry skin. The involved patches don't darken with sun exposure the way the surrounding skin does. Treatment involves daily lubrication with a good moisturizer (such as Aquaphor), especially whenever the skin gets wet. Using sunscreen can decrease the appearance of the patches by inhibiting the skin around them from darkening. Sometimes topical steroid creams help. Even with no treatment at all, the spots will disappear on their own -- although it may take months to years.
The other extremely common white-patch condition is called tinea versicolor. This is a mild, superficial fungal infection, somewhat similar to ringworm (true ringworm can also result in white patches). Tinea versicolor is most common in adolescents and young adults 15 to 30 years old (although it can certainly happen at any age). The infection is chronic and recurs easily, but it causes no other health problems. People are most susceptible to the fungus during hot months in humid areas.
Topical antifungal medicines are very effective for treating tinea versicolor, but there is a more convenient, less expensive, highly effective alternative. Selenium shampoos, such as Selsun Blue, are great at getting rid of the fungus. Simply apply a thin layer over the affected skin before bed (with a wide surrounding margin, since it may already be beginning to spread). Wash thoroughly the next morning.
Also, re-treating once a week for 3-4 weeks and then once a month for 3-4 months makes it much less likely to come back.
With either pityriasis alba or tinea versicolor, even when the condition is effectively treated, the white patches will remain for a while. At least several weeks must pass for the newly healthy skin to adjust its color to the amount of ongoing sunlight exposure, so that it will match the surrounding skin.
ref:http://www.drgreene.org/body.cfm?id=21&action=detail&ref=636
If none of these treatments work you may need to visit an allergist/dermatologist.