Dermatology Lecture Notes Review

Flashcards for review based on lecture notes on inherited skin conditions, viral infections, and related treatments.

Ichthyosis

Abnormal keratinization of the epidermis, leading to scales.

Polygonal scales in Ichthyosis

Scales attached centrally and free at the periphery.

Ichthyosis Vulgaris

Autosomal dominant ichthyosis with onset after 3 months, fine scales, and often associated with atopic dermatitis.

Cause of Ichthyosis Vulgaris

Gene defect in filaggrin (keratin aggregating).

Clinical Picture of Ichthyosis Vulgaris

Dryness in winter, improvement in summer, extensor aspects most prominent, major body folds spared.

X-linked Ichthyosis

X-linked ichthyosis with onset before 3 months of life, dark large tan or grey scales, and sparing of palms and soles.

Associations of X-Linked Ichthyosis

Corneal opacity, cryptorchidism.

Lamellar Ichthyosis

Autosomal recessive ichthyosis with thick large scales, hyperkeratosis of palms and soles, and ectropion.

Initial Presentation of Lamellar Ichthyosis

Collodion membrane at birth.

Treatments of Ichthyosis

Regular moisturizers, keratolytics, systemic retinoid.

Xeroderma Pigmentosum

Inherited extreme sensitivity to UV rays due to mutations in DNA excision repair genes.

Clinical Picture of Xeroderma Pigmentosum

Photosensitivity, prolonged sunburn, skin cancer before 10 years, and areas of hyper- and hypopigmentation.

Epidermolysis Bullosa

Rare genetic disorders with defects of adhesion molecules, leading to blisters from minor physical injury.

Types of Epidermolysis Bullosa

Intraepidermal, Junctional, Dystrophic.

EB Simplex Characteristics

Autosomal dominant, Keratin gene mutations, Intraepidermal blistering.

Junctional EB Characteristics

Autosomal recessive, laminin-332/collagen VII mutations, lamina lucida blistering.

Dystrophic EB Characteristics

Autosomal dominant & recessive, COL7A1 gene mutation, sublamina densa cleavage.

Severe Generalized Junctional EB (Herlitz)

Generalized blisters at birth, erosions around mouth, eyes, nares, and hypertrophic granulation tissue.

Recessive Dystrophic EB

Cutaneous & mucosal hemorrhagic blisters at birth, digital fusion, high risk of cutaneous SCC.

Investigations for Epidermolysis Bullosa

DNA mutation analysis, skin biopsy, bacterial cultures, imaging for GI dysfunction.

Management of Epidermolysis Bullosa

Symptomatic treatment, gene therapy, family education, palliative care.

Leprosy (Hansen's Disease)

Chronic infection of peripheral nerves & skin caused by Mycobacterium leprae bacilli.

Mode of transmission for Leprosy

Droplet: nasal secretion, rare: skin contact.

Clinical-immunologic spectrum of Leprosy

Tuberculoid, Lepromatous, Borderline

Tuberculoid Leprosy Characteristics

Intact cell-mediated immunity, single or few well-defined plaques, unilateral nerve affection.

Lepromatous Leprosy Characteristics

Multiple poorly defined erythematous lesions, bilateral & symmetrical nerve affection late in disease.

Borderline Leprosy Characteristics

Intermediate features, asymmetrical lesions, asymmetrical nerve affection.

Type 1 Leprosy Reaction (Reversal)

Acute erythematous changes in old lesions + inflammation of nerves.

Type 2 Leprosy Reaction (Erythema Nodosum Leprosum)

Small vessel vasculitis, acute fever, bilateral symmetrical erythematous nodules on face and extremities.

Investigations for Leprosy

Slit skin smear, skin biopsy

Treatment of Leprosy

Multidrug therapy (Rifampin, Clofazimine, Dapsone).

Types of Viral Infections

Vesicular and Papular

Human Herpesviruses (HHV)

HSV1-2, VZV, EBV, CMV, HHV6-8

Mode of Transmission for HSV-1

Direct contact (saliva or secretions)

Mode of Transmission for HSV-2

Sexual contact.

Pathogenesis of Primary HSV Infection

Replicates at mucocutaneous site ascends peripheral nerves to dorsal root ganglion latent.

Pathology of Herpes Simplex Virus (HSV)

Multinucleated giant cells, intraepidermal vesiculation, ballooning & reticular degeneration of keratinocytes.

Clinical Presentation of Primary HSV Infection

Grouped vesicles on erythematous base.

Common Site for Orolabial Herpes Simplex (Recurrent)

Vermelion border of lip.

Herpetic Gingivostomatitis (Primary)

Mouth & lips - lesions appearing on buccal mucosa & gingiva

Primary Genital Herpes Presentation

Erosive balanitis, vulvitis, vaginitis + tender LNpathy.

Herpetic Whitlow Transmission

Digital-genital contact

Lesions Associated with Neonatal HSV Infection

Oral, eye, CNS, internal organs. Bullae & erosions.

Eczema Herpeticum (Kaposi Varicelliform Eruption)

Rapid, widespread cutaneous spread, monomorphic discrete punched-out erosions, hemorrhagic crusts.

Pathognomonic Sign of Ocular HSV (keratoconjunctivitis)

Branching dendritic lesions in cornea.

Diagnosis of Herpes Simplex Virus (HSV)

Tzanck smear, viral culture, immunofluorescence, PCR.

General Measures to Treat Primary Herpes

Avoid predisposing factors, Hospital & immuno-stimulant.

Systemic Treatment for Primary and Recurrent Herpes

Acyclovir (Zovirax), Famcyclovir

Mode of transmission of Varicella Zoster Virus

Airborne droplets, Direct contact with vesicular fluid.

Most Common Complaints of Chicken Pox

Itching

Pathogenesis of Chicken Pox

2-4d of viral replication in regional LNs-1ry viremia

Clinical Picture of Chicken Pox

Eruption of pruritic erythematous lesions on scalp & face, spreads to trunk extremities oral mucosa

Eruption Presentation During Chicken Pox

Dew drops on rose petal

Complications from Chicken Pox

Secondary bacterial infection, encephalitis & acute cerebellar ataxia

VZV Vaccine Type

Live attenuated (Varivax)

Herpes Zoster (Shingles)

Incidence & severity in middle to late adulthood.

Pathogenesis of Herpes Zoster (Shingles)

Replicate in dorsal root ganglion causing painful ganglionitis severe neuralgia

Clinical Picture of Herpes Zoster (Shingles)

Painful eruption of grouped vesicles on an erythematous base unilateral dermatomal distribution.

Zoster Sine Herpete

Without skin lesions, patients have all symptoms except Rash

Ramsy Hunt Syndrome

Ext auditory canal, tympanic membrane, anterior 2/3 of tongue & hard palate, ear pain, peripheral facial nerve paralysis.

Most Common Complication of Herpes Zoster

Postherpetic neuralgia

Topical Treatment for Shingles

Analgesic or anesthetic creams, Antibiotics if secondary infected

Systemic treatment for Shingles

Antiviral acyclovir, Analgesic for pain and anti-inflammatory

Human Papilloma Virus (Warts)

High & low risk types (oncogenic potential)

HPV-16 and -18

Primary etiologic agent for cervical cancer

Mode of Transmission for HPV

Sexually transmitted.

Pathogenesis of HPV

Primary target is Basal keratinocytes through minor abrasions & maceration

Pathology of Common Warts

Well circumscribed, with church spire papillomatosis + ortho- and parakeratosis

Koilocytotic cells

Round cell that is vacuolated

Verruca Vulgaris

Hyperkeratotic, exophytic, dome-shaped papules on fingers and dorsal surfaces of hands.

Verruca Palmaris et Plantaris

Painful, Endophytic papules on palms, soles, lateral hands & feet. Painful from pressure when walking

Verruca Plana

Skin colored or pinkish to brown smooth, elevated, flat-topped papules

Verruca Filiform

Slender exophytic warts, in periorificial locations on face

Verruca Digitiform

Finger projections

Condylomata Accuminata

Large cauliflower, non-oncogenic (type 6,11), pedunculated or broad-based papillomas.

Oral Condylomas HPV & 11 Transmission

Oral-genital sexual transmissions

Complications from HPV

Precancerous: CIN, VIN (HPV 16-18) & MC cancer is cervical cancer and anal - Laryngeal papillomata

Local destructive therapies for warts

Cryotherapy, Electrocautery, Surgical excision or shave excision

Pharmacological Treatment of Genital Warts

Podophyllin

Treatment for Multiple or Recurrent Warts

Imiquimod 5%

Retinoid Medication used for Warts

Acitretin, isotretinoin, Topical tretinoin or tazarotene

HPV Vaccine (Quadrivalent)

Quadrivalent of HPV-6, 11, 16, 18 VLPS (Gardasil)

HPV Vaccine (Bivalent)

Bivalent of HPV-16.-18 VLPS (Cervarix)

Molluscum Contagiosum (MC)

MC poxvirus infection in humans- Self-limited condition in children, adults

Mode of Transmission for Molluscum Contagiosum (MC)

Skin-to-skin contact, fomites (less common)- Sexually transmitted

Clinical Picture of Molluscum Contagiosum (MC)

Firm, umbilicated, pearly papules, waxy surface. MC: skin folds; lateral trunk, thighs, buttocks, genital region.

Pathology of Molluscum Contagiosum (MC)

Large intracytoplasmic inclusion bodies in keratinocytes, fin size toward skin surface: Molluscum bodies

MC Treatment Options

Curettage, Electrocautery, Needle transfixion

Molluscum Dermatitis Treatment

Topical CST ipruritus & autoinoculation from scratching

Main symptom of Herpes Simplex

Burning Sensation

Main symptom of Chicken Pox

Itching

Main symptom of Herpes Zoster

Pain

Viral infections are located mostly here

Epidermis

All viral infections transmitted via…

Skin-to-skin contact except VZV via air droplets

At delivery with a pregnant patient with genital warts perform this

Caesarean delivery

Genital Wart Treatments

Cryo, Chemical Treatment

Most common cancer from HPV virus

Cervical Cancer and Anal

Off label use in Molluscum Contagiousum

Imiquimod

A group of inherited skin conditions

Genodermatoses

H&E of Ichthyosis

Compact orthokeratosis and granular layer