Brief Answer:
I suggest a possibility of Lichen planus/ Lichenoid dermatitis

Detailed Answer:
Hello. Thank you for writing to us at healthcaremagic

I have gone through your query and I have also reviewed the Image

I can see small, bluish, scaly patches on left inner thigh.

I will keep a possibility of Lichen Planus/ Lichenoid dermatitis. In common language we can say that it is type of Eczema.
Lichen planus classically presents with bluish/ purplish, raised, scaly, itchy lesions.
Lesions of Lichen planus can be distributed at various body sites like abdomen, shins, arms and legs.
Characteristic feature of Lichen planus is that it is extremely pruritic/ itchy.

Do you have similar lesions elsewhere?

Treatment is with topical corticosteroids and Oral antihistamines.

I suggest you to use a potent topical steroid e.g clobetasol propionate 0.05% Or mometasone furoate 0.1% cream, twice daily.
It is a prescription topical steroid, therefore, I suggest you to talk to your doctor for the needful.
An OTC oral antihistamine e.g cetrizine 10 mg once daily will provide you symptomatic relief from itching.

Regards

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Brief Answer:
Lichen planus has an Immune etiology

Detailed Answer:
Hi.

Thank you for clarification.
For a limited involvement such as yours topical steroids creams would be appropriate together with Oral antihistamine e.g cetrizine.

Otherwise for an extensive involvement Oral steroids may also be required.

Lichen planus is a type of eczema and the cause is usually autoimmune/ immune related Or to be more precise immune imbalance.

It is a self limiting condition and usually settles down with adequate treatment.

Regards

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