DERMATOLOGY - Practice Flashcards from Lecture Notes

A set of concise question-and-answer flashcards covering key dermatology topics from the notes, including psoriasis pathology, lichen planus, pityriasis versicolor, fungal infections, vitiligo, genetic syndromes, and systemic skin diseases.

What is Munro microabscess?

A neutrophilic microabscess in the stratum corneum seen in psoriasis.

What is Pautrier’s microabscess?

Intraepidermal collections of neuts in the epidermis, classically seen in mycosis fungoides.

Civatte bodies are associated with which skin condition?

Lichen planus (degeneration of basal keratinocytes with Civatte bodies).

Define parakeratosis.

Retention of nuclei in the stratum corneum.

Define hyperkeratosis.

Thickening of the stratum corneum.

Define orthokeratosis.

Keratinization with loss of nuclei in the stratum corneum.

Wickham’s striae are characteristic of which disease?

Lichen planus (fine white lines on lesions).

What patch marks the initial presentation of pityriasis rosea?

Herald patch.

What scale pattern is typical of pityriasis rosea?

Collarette (cigarette paper) scale around the lesion.

What pattern is described as a 'Christmas tree' on KOH/mount in dermatology?

Pattern associated with Pityriasis rosea (as described in these notes with SDA + olive oil).

Features of Pityriasis rubra pilaris (PRP)?

Perifollicular hyperkeratosis, islands of sparing, and palmoplantar keratoderma.

Spaghetti and meatball appearance on microscopy is seen with which organism/group?

Malassezia species (Pityriasis versicolor) on KOH mount.

Wood’s lamp fluorescence for Malassezia (tinea versicolor) is typically:

Golden yellow fluorescence.

Distal Lateral Subungual Onychomycosis (DLSO) refers to which condition?

The most common pattern of nail fungus (onychomycosis).

Kerion is most commonly caused by which organism?

Trichophyton mentagrophyte (tinea capitis).

Hair perforation test is positive for which fungus?

Trichophyton mentagrophyte.

Pitted keratolysis is associated with which conditions/findings?

Moisture-related plantar pits; associated with Micrococcus (per notes).

Milian’s ear sign is characteristic of which condition?

Staphylococcal Scalded Skin Syndrome (SSSS).

Which organism is the common cause of kerion (tinea capitis) as per these notes?

Trichophyton mentagrophyte.

Impetigo: bullous vs non-bullous etiologies?

Bullous impetigo is usually due to Staphylococcus aureus; non-bullous impetigo is usually due to Streptococcus pyogenes.

Erysipelas vs cellulitis: how do they differ?

Erysipelas has well-defined, raised lesions affecting the superficial dermis; cellulitis is ill-defined and deeper (epidermis + dermis).

Vitiligo: what causes depigmented patches and what are key signs?

Autoimmune destruction of melanocytes; Wartenberg’s sign, leukotrichia; segmental vs non-segmental patterns; treated with topical steroids or tacrolimus.

What are Blaschko lines?

Embryological patterns of skin cell migration; often invisible but revealed in certain disorders.

What are Lines of Langer (Langer’s lines)?

Skin tension lines used to guide surgical incisions.

SCORTEN is used to predict mortality in which condition?

Toxic Epidermal Necrolysis (TEN).

Kaposi sarcoma is associated with which virus and condition?

HHV-8; AIDS and related immunosuppression; known sign 'lollipop sign'.

Sign of Lesser-Trelat is associated with which condition?

Paraneoplastic manifestation of seborrheic keratoses (sudden eruption may indicate internal malignancy).

Which gene is mutated in Netherton syndrome (PIBIDS) and what are key features?

SPINK5 gene; features include ichthyosis, brittle hair (trichorrhexis invaginata), photosensitivity.

What hair findings are described in Netherton syndrome (PIBIDS)?

Bamboo hair and 'tiger tail' hair defects.

What is isotretinoin used for, and what are major precautions?

Isotretinoin for severe nodulocystic acne; teratogenic; requires washout period (~3 months) before pregnancy, may cause hepatotoxicity and lipid abnormalities and cheilitis.