Between Tinea capitis and Psoriasis of the scalp

 A 6-year-old child presents complaining of patchy hair loss on the back of the scalp. Examination reveals well-demarcated areas of erythema and scaling, and although there are still some hairs in the area, they are extremely short and broken in appearance. Which of the following is the most likely diagnosis?

• a.Androgenic hair loss
• b.Psoriasis of the scalp
• c.Seborrheic dermatitis
• d.Tinea capitis
• e.Carbuncle

 The answer is d. 

The history is most consistent with tinea capitis due to either Trichophyton tonsurans or Microsporum canis. It is usually seen in school-age children and may be transmitted from person to person.

 A mild but widespread infection by Tinea capitis (Scalp ringworm). Inflamed areas are seen on the front, behind the ear and on the back of the neck.Black dots are from broken hair

Psoriasisis a hereditary disorder characterized by scaling patches and plaques appearing in specific areas of the body, such as the scalp, elbows, lumbosacral region, and knees. The lesions are “salmon pink” with a silver-colored scale that on removal produces blood (Auspitz sign). The Koebner phenomenon (with trauma, the lesion jumps to a new location) is also elicited in patients with psoriasis.
Seborrheic dermatitisis a common chronic dermatosis occurring in areas with active sebaceous glands (face, scalp, and body folds) and may occur either in infancy or in people over the age of 20. The eczematous plaques of seborrheic dermatitis are yellowish red and are often greasy with a sticky crust. Androgenic hair loss is a progressive hereditary bitemporal, frontal, or vertex balding that may begin any time after puberty. A carbuncle is a deep infectious collection of interconnecting abscesses (furuncles) arising from several hair follicles.