Skin infections and dermatologic meds

Derm items sort infection, drug emergency, and teaching-heavy acne or steroid care. Pressure injuries and wound staging live elsewhere; here the exam wants cellulitis versus abscess, SJS/TEN as a burn-level crisis, isotretinoin pregnancy rules, and smart topical steroid use.

Cellulitis versus abscess

Cellulitis is spreading infection of dermis and subcutaneous tissue, usually bacterial entry through a break in skin. The border is warm, erythematous, and tender; fever and malaise mean systemic involvement. Marking the edge with a pen shows whether antibiotics are winning. Elevate the limb to reduce edema, give ordered antibiotics, and watch for deeper infection — rapid spread, crepitus, severe pain out of proportion, or toxic look pushes toward necrotizing infection pathways, not another day of watchful waiting.

An abscess is a walled-off pocket of pus. It feels fluctuant (gives under pressure) and is often more localized than cellulitis, though both can coexist (cellulitis with an abscess underneath). Antibiotics penetrate poorly into avascular pus, so incision and drainage is frequently required. On exams, choosing “antibiotics only” for a clearly fluctuant, pointing lesion is the distractor; choosing I&D talk for flat, non-fluctuant cellulitis without a collection is the opposite error. Warm compresses may help bring an early furuncle to a head when ordered; do not squeeze — that forces bacteria into deeper tissue and veins.

• Culture and blood work follow facility protocol when systemic signs appear.
• Diabetes and immunocompromise raise depth and speed of spread — lower your threshold to escalate.
• Tetanus status matters with traumatic portals of entry.

SJS and TEN: stop the drug, burn-like care

Stevens–Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) sit on a spectrum of severe cutaneous adverse reactions. A medication — classic exam culprits include certain anticonvulsants, allopurinol, and sulfa antibiotics — triggers widespread keratinocyte death. A flu-like prodrome precedes painful erythema, blistering, and sheet-like detachment; mucosal surfaces (oral, ocular, genital) are involved early. Nikolsky-type fragility may appear. This is not a mild drug rash you “push through.”

First move: stop the suspected drug and escalate. Support looks like burn care because barrier loss drives fluid, temperature, and infection risk — airway watch if face/mouth involved, fluid resuscitation as ordered, sterile handling, reverse isolation or infection precautions per protocol, eye lubrication and ophthalmology involvement, pain control, and wound care without aggressive debridement freelancing. Do not restart the culprit. Document the drug allergy permanently. Related severe drug reactions and infection isolation patterns also connect to broader antimicrobial teaching, but the bedside priority here is stop–support–specialty.

1. Stop suspected drug immediately; list it as allergy.
2. Airway, fluids, skin barrier, eyes — burn-team thinking.
3. No challenge doses on the exam stem.

Acne therapy and isotretinoin

Mild acne teaching starts with gentle cleansing, non-comedogenic products, and ordered topicals (retinoids, benzoyl peroxide, antibiotics). Systemic antibiotics appear for inflammatory disease; remind clients that improvement takes weeks, not overnight. The high-stakes drug is oral isotretinoin for severe nodular acne. It shrinks sebaceous activity and is powerfully teratogenic — fetal exposure causes severe birth defects. Enrollment in a risk program (iPledge or equivalent as tested) means documented contraception counseling, monthly requirements as protocol states, and negative pregnancy tests per rules before refills.

Teach dryness of lips and skin, nosebleeds, and photosensitivity as expected effects — lip balm and moisturizer are nursing teaching, not failure of therapy. Night vision changes and mood or depression questions should be reported. Do not share medication. Blood donation is deferred during and for a period after therapy as commonly taught, because a pregnant recipient could be harmed. Triglyceride and liver monitoring appear as ordered labs — nursing role is adherence and reporting, not inventing dose changes.

Topical anti-inflammatory agents

Topical corticosteroids reduce local inflammation in eczema and dermatitis by genomic anti-inflammatory effects in skin cells. Potency ranges from hydrocortisone-class mild agents to very high-potency drugs used for thick plaques. Thin skin — face, eyelids, genitals, intertriginous folds, and pediatric skin — absorbs more and atrophies faster. High-potency steroid on the face for weeks is a classic wrong answer; use the lowest effective potency for the shortest time, and follow ordered step-down.

Apply a thin film to affected skin only; more cream does not mean faster cure and does raise adverse effects. Occlusion (wraps, tight plastic) dramatically increases absorption — only when prescribed. Steroids can mask or worsen cutaneous infection; if the lesion looks more pustular or the client spikes fever, reassess. Systemic steroids for severe flares connect to endocrine teaching in Oral antidiabetics and corticosteroids; keep this section focused on topical technique and site caution.

• Face and folds: mild potency unless a specialist order says otherwise.
• Fingertip unit teaching helps families avoid over-application.
• Report skin thinning, striae, or nonhealing areas under chronic steroid use.

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