Select the components of blood. Select All That Apply.

Rationale:

A. Raised, solid lesion less than 1 cm in diameter is correct. A papule is a small, elevated, solid lesion of the skin that is typically less than 1 centimeter in diameter. Papules can result from a variety of dermatologic conditions, including inflammatory responses, infections, or benign growths, and they are distinct from vesicles or pustules because they do not contain fluid or pus.

B. Non-inflammatory lesion with darkened color due to oxidation is incorrect. This description corresponds to a comedo, such as a blackhead, which is a type of acne lesion formed by oxidized sebum in clogged hair follicles. While comedones are common in acne, they are not considered papules because they are not solid raised lesions caused by cellular proliferation or inflammation.

C. Inflamed bump on the skin that can be tender to the touch is incorrect. While some papules may become inflamed and tender, the defining characteristic of a papule is its size and solid, raised nature, not necessarily inflammation. Inflammatory bumps that are tender and red may be better classified as pustules or nodules depending on their content and size.

D. Large, firm lesion containing purulent material is incorrect. This description defines a pustule or abscess, which contains pus composed of white blood cells, bacteria, and cellular debris. Papules do not contain fluid or pus, making this option inconsistent with the definition of a papule.

Rationale:

A. Psoriasis is a chronic autoimmune-mediated skin disorder characterized by hyperproliferation of keratinocytes and inflammation. Clinically, it presents as well-demarcated, erythematous plaques covered with silvery-white scales, often found on extensor surfaces such as the elbows, knees, scalp, and lower back. Psoriatic lesions are typically not ring-shaped, nor do they have a clear center, so psoriasis does not match the client’s description.

B. Tinea capitis is a fungal infection caused primarily by dermatophytes affecting the scalp. It presents with scaling, hair loss, broken hairs, and sometimes pustules or kerion formation. Lesions occur on the scalp and hair-bearing areas, not usually on the arm, and the classic ring-shaped pattern with central clearing seen in tinea corporis is not characteristic of tinea capitis.

C. Eczema (atopic dermatitis) is a chronic inflammatory skin condition associated with impaired skin barrier function and immune dysregulation. It typically presents as pruritic, erythematous, and sometimes oozing patches. The lesions are often irregularly shaped, may be lichenified, and lack the ring-shaped configuration with central clearing. While eczema can affect the arms, the pattern described in the client does not align with classic eczema presentation.

D. Tinea corporis, also known as ringworm of the body, is a superficial fungal infection caused by dermatophytes such as Trichophyton species. The pathophysiology involves fungal invasion of the stratum corneum, which induces an inflammatory response in the surrounding skin. Clinically, tinea corporis presents as annular (ring-shaped) lesions with raised, scaly borders and central clearing, which is highly distinctive. The clear center results from the resolution of fungal activity in the central area while the fungus continues to proliferate at the edges, producing the characteristic ring pattern. Lesions may be single or multiple and can occur on any exposed skin area, including the arms, legs, and trunk. The presence of a ring-shaped lesion with a clear center, as reported by the client, is a classic hallmark of tinea corporis, making this the most likely diagnosis.