How is non-fluctuant paronychia managed?
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Manage non-fluctuant paronychia with warm soaks multiple times daily, elevation, and topical mupirocin; oral antibiotics usually not necessary.
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How is non-fluctuant paronychia managed?
Manage non-fluctuant paronychia with warm soaks multiple times daily, elevation, and topical mupirocin; oral antibiotics usually not necessary.
What key counseling point is important about recurrence for HPV genital warts after treatment?
Genital warts often recur even after treatment, so counsel patients about the possibility of recurrence and discuss HPV vaccination for prevention.
Which topical medication is specifically contraindicated for skin folds in fungal infections?
Clotrimazole/betamethasone combinations (steroid-antifungal creams) should NEVER be prescribed for skin folds (e.g., tinea cruris) due to risk of worsening infection.
Name an office procedure used for refractory cutaneous warts.
Options include cryotherapy (liquid nitrogen), paring with a #15 blade, and cantharidin application; refractory cases may need injections (Candida albicans) or other measures.
What is a kerion and what complication can it cause?
A kerion is a severe inflammatory form of tinea capitis with systemic symptoms; it can cause scarring alopecia if not properly treated.
Name systemic conditions that can cause hair loss (alopecia).
Systemic causes include SLE, secondary syphilis, hyper/hypothyroidism, and iron deficiency anemia.
What treatments are used for alopecia areata?
Treat with topical steroids, intralesional steroid injections, and oral JAK inhibitors (e.g., ritlecitinib, baricitinib).
Why is ophthalmic shingles considered urgent?
Ophthalmic shingles can infect the eye and cause blindness, so urgent ophthalmologic evaluation is required upon diagnosis.
List first-line treatment options for androgenetic alopecia.
Treatments include topical Minoxidil 5% (OTC), Finasteride 1 mg PO daily, oral Minoxidil (1.25–5 mg PO), and Spironolactone for female pattern hair loss.
What are the key clinical features of alopecia areata?
Alopecia areata presents with sudden, well-defined, smooth, non-scarring round/oval patches of hair loss and "exclamation hairs" (short hairs ~2–3 mm).
Define paronychia and common causative organisms.
Paronychia is infection of the lateral (or proximal) nail fold; most commonly caused by Staphylococcus aureus and Streptococcus species.
How is fluctuant paronychia treated?
Fluctuant paronychia requires incision and drainage (I&D) (can be done without a digital block), followed by elevation, warm soaks, immobilization, and topical antibiotics; PO antibiotics if systemic signs or immunocompromised.
What is a felon?
A felon is a subcutaneous pyogenic infection of the pulp space of the distal finger or thumb, usually after minor trauma.
Which organism is most commonly responsible for a felon?
Staphylococcus aureus (including MRSA) is the most common causative organism for a felon.
List key signs/symptoms and complications to watch for with a felon.
Features include a red, tense, markedly painful distal pulp space. Complications: spread to flexor tendon sheath, interphalangeal joints, or periosteum → osteomyelitis.
Describe the treatment steps for a felon.
Treat with digital block anesthesia, then I&D via a longitudinal/lateral approach with an #11 blade to drain exudate and break septae; do not pack; give adjunctive antibiotics only for systemic signs or immunocompromise.
What simple procedures are used for partial nail avulsion?
Partial nail avulsion techniques include lifting the nail edge from the bed with a Freer elevator and separating the nail with a scalpel, then grasping and removing the nail with fine-tipped scissors.
What clinical features help distinguish verruca (wart) from other lesions?
Warts are round, flesh-colored, hyperkeratotic lesions that may have thrombosed capillaries (black dots), disrupt skin lines, and vary by morphology (flat, mosaic, filiform).
How long is the incubation period for cutaneous warts (HPV)?
The incubation period for HPV causing cutaneous warts is typically 2–6 months.
Who is most at risk for cutaneous warts?
Warts are most common in children and young adults, and in occupations handling meat/poultry/fish; risk increased with atopic dermatitis or decreased cell-mediated immunity.
List common treatments for cutaneous warts.
Treatments: paring with a #15 blade, salicylic acid, liquid nitrogen (cryotherapy), cantharidin, and Candida albicans injections. Many regress spontaneously (≈65% over 2 years).
What HPV types cause condyloma acuminatum and what do lesions look like?
Condyloma acuminatum (genital warts) is caused mainly by HPV types 6 and 11 and appears as gray or flesh-colored, pedunculated, moist papules that can be multiple and variable in size.
How is condyloma acuminatum diagnosed and confirmed?
Diagnosis is clinical; confirmation of HPV infection can be by colposcopy, PAP, or PCR.
Describe treatment options and prevention for genital warts.
Treatment focuses on symptomatic/cosmetic relief: imiquimod 5% cream, podofilox 0.5%, cryotherapy, or laser for refractory cases. HPV vaccine can prevent infection. Recurrence is common.
What virus causes Molluscum contagiosum and how does it present?
Molluscum contagiosum is caused by a poxvirus and presents as flesh-colored, dome-shaped papules with central umbilication, often multiple and very contagious.
Where are molluscum lesions commonly found and what populations are at risk?
Lesions occur on face, trunk, extremities, lips/tongue, and genitals (can be an STD); common in children, swimmers, and wrestlers.
What are treatment options for molluscum contagiosum?
Options: benign neglect (self-limited 1–2 years), liquid nitrogen, cantharidin, curettage, imiquimod, and silver nitrate.
How is Hand‑Foot‑Mouth disease transmitted and who is most affected?
Transmitted via fecal-oral, respiratory droplets, and fomites; most common in children <10 years, but adults can be infected with more severe/atypical disease.
What are typical clinical features and course of Hand‑Foot‑Mouth disease?
Features: fever, painful oral ulcers (herpangina), sore throat, and papulovesicular rash on hands/feet ("American football" shaped on palms/soles). Incubation 3–6 days; resolves in 7–10 days.
How is Hand‑Foot‑Mouth disease managed?
Management is supportive: hydration and pain control (acetaminophen/ibuprofen). No approved antivirals; PCR for severe/outbreak cases.
Describe the classic lesion appearance of herpes simplex.
HSV lesions are described as "dew drop on a rose petal"—grouped vesicles on an erythematous base that can become erosions and crusts.
Differentiate typical anatomical presentations of HSV-1 and HSV-2.
HSV-1 typically causes oral herpes (cold sores) but can cause genital disease; HSV-2 is most commonly the cause of genital herpes with painful vesicular or ulcerative lesions.
How is HSV diagnosed and what are initial/long-term antiviral treatments?
Diagnosis by lesion swab for NAAT; serology for exposure. Initial treatment: Valacyclovir 1 g BID or Acyclovir 400 mg TID x 7 days. Suppressive therapy: Valacyclovir 1 g QD or Acyclovir 400 mg BID.
Give population prevalence data for HSV-1 and HSV-2 (2024 data mentioned).
HSV-1 seroprevalence: ~38% in children, ~64% in adults. HSV-2 overall prevalence is ~11% and has been declining since the 1980s.
What triggers reactivation of varicella‑zoster virus (shingles) and how does it present?
Reactivation often triggered by immunosuppression or advanced age; presents as unilateral, painful vesicular rash in a single dermatome with possible prodromal localized pain.
What is the recommended antiviral therapy for shingles and timing?
Valacyclovir 1 g TID x 7 days, ideally started within 72 hours of rash onset.
List major complications of varicella‑zoster infection.
Complications include postherpetic neuralgia, ophthalmic shingles (risk of blindness), Ramsay Hunt syndrome, and encephalitis/meningitis.
Who should receive the Shingrix vaccine and what is its effectiveness?
Adults >50 years (and immunocompromised) should receive 2 doses 2–6 months apart; Shingrix is >90% effective in preventing shingles and postherpetic neuralgia.
What fungus commonly causes onychomycosis (toenail fungus) and what are its signs?
Onychomycosis is commonly caused by Tinea rubrum; signs include yellow, thick, brittle nails, especially in toenails.
How is onychomycosis diagnosed in clinic?
Diagnose clinically and confirm with KOH 10% preparation of nail scrapings to look for hyphae under microscopy.
Compare oral antifungal treatment durations for fingernail vs toenail onychomycosis.
Fingernails: griseofulvin or terbinafine x 6 weeks. Toenails: terbinafine x 12 weeks. Topicals usually less effective and treatment often takes months.
What are common signs and distribution of tinea pedis (athlete's foot)?
Tinea pedis presents with itching, odor, vesicles/erosions/scaling, typically on the soles (moccasin distribution) and between toes.
How is tinea pedis diagnosed and treated?
Diagnosis: clinical ± microscopic exam of scraping for hyphae. Treatment: topical antifungals (miconazole, clotrimazole, terbinafine cream) and keep feet dry.
What areas are affected by tinea corporis and how does it present?
Tinea corporis affects non-hairy skin (face, arms, legs, trunk) and presents as itchy, well-defined circular patches with scaly borders ("ringworm").
What topical treatments are effective for tinea corporis and which medication is ineffective?
Effective topical antifungals include miconazole and ketoconazole; nystatin is NOT effective for dermatophytes.
Describe tinea capitis epidemiology and key signs.
Tinea capitis is a scalp/hair shaft fungal infection most common in toddlers and school-age children; signs include round scaly patches with broken hairs, black dots, and possible tender areas; severe kerion can cause scarring alopecia.
What is the treatment of choice for tinea capitis?
Oral antifungals are most effective: terbinafine, itraconazole, or fluconazole.
What is tinea cruris and who is predisposed?
Tinea cruris ("jock itch") is a fungal infection of the groin, common in obese patients, athletes, wearers of tight clothing, and in hot/humid climates.
What are the treatment recommendations and contraindications for tinea cruris?
Treat with loose clothing, topical antifungals, and barrier creams; never prescribe clotrimazole/betamethasone for skin folds. Use oral antifungals for extensive/resistant cases.
What causes tinea versicolor and why is it more noticeable in summer?
Tinea versicolor is due to overgrowth of Malassezia furfur; lesions are more noticeable in summer because affected areas do not tan and contrast with surrounding tanned skin.
Describe the appearance and common locations of tinea versicolor.
Presents as multiple oval patchy lesions with fine scale, either hypopigmented or hyperpigmented, typically on the back, neck, chest, and shoulders.
What topical and systemic treatments are used for tinea versicolor?
Topical antifungals include miconazole and ketoconazole (nystatin ineffective). Widespread disease is treated with oral fluconazole; recurrence is common.
Which fungal infections commonly require oral antifungals rather than topicals?
Tinea capitis and extensive onychomycosis (toenail) often require oral antifungals; tinea capitis responds best to oral therapy.
Which dermatologic conditions are commonly self-limited and may be managed conservatively?
Molluscum contagiosum (often resolves in 1–2 years) and many cutaneous warts (≈65% spontaneously regress over 2 years) can be managed with benign neglect in select cases.
What diagnostic test is useful for fungal skin/nail scrapings and what does it detect?
A KOH 10% preparation of scrapings reveals branching hyphae, which supports a dermatophyte/fungal infection diagnosis.
When are oral antibiotics indicated for paronychia or felon?
Oral antibiotics are indicated when there are systemic signs of infection (fever, tachycardia, leukocytosis), immunocompromise, or failure to respond to drainage/initial care.
What lesion distribution distinguishes shingles from disseminated disease?
Shingles typically affects a single unilateral dermatome; disseminated disease (multiple dermatomes or crossing midline) suggests immunosuppression.
Which antifungal is commonly used topically for tinea pedis and tinea versicolor?
Topical agents such as miconazole and ketoconazole are used for tinea pedis and tinea versicolor; terbinafine cream is also effective for tinea pedis.
For herpes simplex, what testing helps confirm active infection versus past exposure?
Lesion swab for NAAT (nucleic acid amplification test) confirms active infection; serology indicates past exposure.
Which dermatologic infections discussed are commonly sexually transmitted or can present on genitals?
Condyloma acuminatum (HPV) and molluscum contagiosum can be sexually transmitted and present on the genital mucosa.
What is the classic palm/sole lesion shape described in Hand‑Foot‑Mouth disease?
Lesions on palms/soles are described as "American football" shaped papulovesicles.
Which antifungal is first-line oral therapy for toenail fungus and typical duration?
Terbinafine is first-line for toenail onychomycosis, usually given for 12 weeks.
When should antiviral therapy for shingles be started for best effect?
Start antiviral therapy within 72 hours of rash onset for best efficacy in reducing viral replication and complications.
Which wart treatment uses an oil derived from blister beetles?
Cantharidin is an odorless, colorless vesicant oil secreted by blister beetles used to treat warts.
What are thrombosed capillaries and which lesion are they associated with?
Thrombosed capillaries are small black dots seen within cutaneous warts (verruca) representing thrombosed blood vessels.
Why are topical treatments often ineffective for onychomycosis?
Toenail onychomycosis resides under a thick nail plate in a moist environment, making topicals penetrate poorly, so oral therapy is often required and treatment is prolonged.
What public health prevention is available for HPV-related disease?
HPV vaccination can prevent infections that cause condyloma acuminatum and other HPV-related diseases.
How does trichotillomania differ clinically from alopecia areata?
Trichotillomania shows irregular patches with short, broken hairs (never totally bald), often unilateral reflecting hand dominance, and is an impulse control/psych disorder.
What factors predispose someone to paronychia?
Predisposing factors include nail biting, manicure trauma, and small foreign bodies in the nail fold.
What is the most common form of alopecia and what influences it?
Androgenetic (male-pattern) alopecia is the most common form; genetics play a strong role and early changes occur at the widow's peak and vertex.
