QCM : Dermatology: Skin Disease Fundamentals — 8 questions

Explication

Chronic Inflammatory Dermatoses are long-lasting skin conditions characterized by persistent inflammation, hyperplasia, and hyperkeratosis, distinguishing them from acute reactions or infectious diseases.

Explication

Herpes simplex virus (HSV) is most commonly associated with triggering erythema multiforme, as it is a well-established precipitant. The other options are less commonly linked to this condition; Staphylococcus aureus can cause skin infections but not typically erythema multiforme, varicella-zoster virus causes chickenpox and shingles, and Candida albicans causes candidiasis.

Explication

Urticaria and erythema multiforme were recognized as part of the acute inflammatory dermatoses group in the early 20th century, around 1910, when dermatology classifications became more standardized. Prior to this, their descriptions were scattered, but the formal grouping in dermatological literature was established in the early 1900s.

Explication

Charles Darwin proposed the theory of natural selection in his 1859 publication 'On the Origin of Species,' establishing it as a fundamental concept in evolutionary biology. Lamarck proposed inheritance of acquired traits, Mendel studied genetics and inheritance patterns, and Wallace independently conceived a similar theory but Darwin is primarily credited for formulating the concept.

Explication

Wickham’s striae are characteristic white lines seen on the surface of papules in lichen planus, helping confirm the diagnosis. Recognizing this feature guides clinicians to appropriate treatment with corticosteroids. The other options are incorrect because Wickham’s striae are specific to lichen planus, not bacterial, fungal infections, or psoriasis.

Explication

Urticaria results from Type I hypersensitivity involving mast cell degranulation, leading to transient, pruritic wheals triggered by allergens or pressure. Erythema multiforme is a hypersensitivity reaction, often to infections like HSV or drugs, characterized by targetoid lesions and less transient. The options correctly contrast the triggers and clinical features of these two conditions.

Explication

A papule is a small, solid, raised skin lesion typically less than 1 cm in diameter, making it distinguishable from a macule, which is a flat, discolored area of skin that is not raised.

Explication

Acute eczematous dermatitis primarily functions as an inflammatory response to irritants or allergens, helping the skin react and adapt to external stimuli. It is not involved in melanin production, hydration, or healing processes directly, but rather acts as a defense mechanism.