Case 1 – Standard Case:
【1】Doorway Information
- Age/Gender: 26-year-old female
- Chief Complaint: Itchy red rash on arms and neck
- Vital Signs: T 36.8°C, HR 78, BP 112/70, RR 14, SpO₂ 98% RA
【2】Structured History
Opening:
“I’ve had flare-ups before, but this one’s really bothering me.”
Shoreline:
“I’ve had eczema since I was a kid, but this past week it’s gotten much worse—itchier and more widespread. I think the weather or something I ate might’ve triggered it.”
- Onset & Course: “It started about 5–6 days ago. First on my elbows, then it spread to my neck and arms. The itching is constant, especially at night.”
- Associated Symptoms: “No fever or pain. Just dryness, cracking, and oozing in some spots.”
- Mood / Function / Appetite / Sleep: “I’m exhausted—I haven’t been sleeping well because of the itch. I feel irritable and distracted during work.”
- Medical History / Medication:
- P: Atopic dermatitis since childhood
- A: None known
- M: OTC moisturizers, occasional topical hydrocortisone
- H/I/T/S: None
- FOSS:
- F: Mother has hay fever and asthma
- O: Irregular periods, otherwise normal
- S: Sexually active, monogamous
- S: Works at a café; frequent handwashing; no tobacco; drinks socially; under stress preparing for exams
- Concerns & Questions: “I’m worried this might leave scars… Should I go back on steroids? Is it something I’m doing wrong?”
【3】Physical Examination
- Positive Findings: Erythematous patches with lichenification on flexural surfaces (antecubital fossae, neck); excoriations; mild crusting
- Important Negative Findings: No systemic signs; no pustules, vesicles, or mucosal involvement
- HEENT: No conjunctivitis, oral mucosa normal
- Chest: Clear to auscultation
- Abdomen: Soft, non-tender
- Neuro: No deficits
【4】Differential Diagnosis (Top 3)
- Atopic Dermatitis (Most likely)
- Supporting: Atopy history, flexural location, lichenification
- Contradictory: None
- Contact Dermatitis
- Supporting: Exposure to detergents at work
- Contradictory: Chronic pattern, symmetric distribution
- Scabies
- Supporting: Severe itching at night
- Contradictory: No burrows, no web space/genital involvement
【5】Clinical Reflection
“She fits the classic triad: atopy, flexural rash, and chronic itch. I’ll need to educate her on triggers, moisturization, and when to use topical steroids properly. She seems motivated.”
【6】Clinical Tips
- “The itch that rashes” – itch often precedes visible changes
- Use emollients regularly even on clear skin
- Scratching fuels the cycle – treat inflammation and habit
- Be cautious with steroids on the face – risk of thinning
- Ask about work and emotional stressors
【7】Challenging Questions
Q: “Is this something I’ll have forever?”
A: “Atopic dermatitis tends to be chronic, but it can improve with age and good skincare. You may always have sensitive skin, but flare-ups can often be prevented or minimized. We’ll work together to find a plan that fits your lifestyle.”
Q: “Can I use stronger steroids to stop this faster?”
A: “Stronger steroids can help during flares, but they should be used carefully. Overuse can cause side effects like skin thinning, especially on the face. I’ll guide you on how to use them safely and effectively.”
【8】📝 SOAP Note
S: 26-year-old female with history of atopic dermatitis presents with a 6-day flare-up. Reports worsening pruritus, especially at night, with dry, erythematous patches on arms and neck. Denies systemic symptoms. Family history of atopy. O: T 36.8°C, HR 78, BP 112/70, RR 14, SpO₂ 98% PE: Lichenified eczematous patches on antecubital fossae and neck, excoriations with mild crusting. No vesicles, pustules, or systemic signs. A: # Atopic dermatitis flare # Chronic pruritus interfering with sleep # Occupational exposure to irritants ddx): Atopic dermatitis, contact dermatitis, scabies r/o): Psoriasis (distribution, no silvery scale), seborrheic dermatitis (location, scale type) → Flare likely triggered by irritant exposure and stress. No signs of secondary infection. Plan includes topical steroid, skin care education, and stress management. P: - Mid-potency topical corticosteroid (e.g., triamcinolone 0.1%) BID for 1 week - Emollient therapy: thick moisturizer multiple times daily - Avoid triggers (detergents, scratching, hot showers) - Follow-up in 1–2 weeks for response and taper guidance - Consider antihistamines at night if sleep remains poor
Case 2 – Challenging Case:
【1】Doorway Information
- Age/Gender: 42-year-old male
- Chief Complaint: Chronic itchy rash on elbows and scalp
- Vital Signs: T 36.5°C, HR 82, BP 130/78, RR 16, SpO₂ 99% RA
【2】Structured History
Opening:
“I thought it was just dry skin at first, but it’s not going away.”
Shoreline:
“Tell me more about that?”
“It started as a patch on my left elbow a few months ago. Then I noticed it on the right side too, and lately, the back of my scalp is super itchy and flaky. I’ve tried moisturizing, but it keeps coming back.”
- Onset & Course: “The first patch was maybe 3–4 months ago. It gets better and worse, but never really goes away. When I scratch, it flakes a lot.”
- Associated Symptoms: “It doesn’t hurt, but it itches like crazy. Sometimes it bleeds a bit when I scratch. No fever or joint pain.”
- Mood / Function / Appetite / Sleep: “It’s embarrassing—people at work think I have dandruff or something contagious. I avoid wearing dark clothes now.”
- Medical History / Medication:
- P: Seasonal allergies
- A: None
- M: OTC dandruff shampoo, moisturizer
- H/I/T/S: None
- PAM HITS FOSS:
- F: Father had “skin problems” in his 50s (unsure of diagnosis)
- O: No known issues
- S: Married, monogamous
- S: Office worker, no occupational exposures. Non-smoker, drinks socially. Under moderate work stress.
- Concerns & Questions: “Do I have some kind of fungus? Or eczema? I just want it to stop coming back.”
【3】Physical Examination
- Positive Findings: Well-demarcated erythematous plaques with silvery scales on bilateral extensor elbows; thick scaly patches at the posterior scalp with mild excoriation
- Important Negative Findings: No mucosal involvement; no nail pitting or onycholysis; no joint swelling or tenderness
- HEENT: Scalp thickly scaled, oral mucosa normal
- Chest: Clear to auscultation
- Abdomen: Normal, non-tender
- Neuro/MSK: Normal strength, ROM; no joint findings
【4】Differential Diagnosis (Top 3)
- Psoriasis vulgaris (Most likely)
- Supporting: Extensor plaques, silvery scale, chronic pattern, scalp involvement
- Contradictory: No nail findings (but not required)
- Seborrheic dermatitis
- Supporting: Scalp involvement, flaking
- Contradictory: Less defined borders, typically oily areas (nasolabial folds)
- Chronic eczema (atopic or irritant)
- Supporting: Chronic itch, dryness
- Contradictory: Flexural pattern lacking, no vesicles
【5】Clinical Reflection
“This isn’t just dry skin—these plaques and the scale pattern scream psoriasis. No joint involvement for now, but we need to monitor for psoriatic arthritis and consider referral if symptoms progress.”
【6】Clinical Tips
- Psoriasis prefers the \”outside\” (extensors); eczema favors the \”inside\” (flexors)
- Scalp psoriasis is often mistaken for dandruff but thicker and persistent
- Nail changes (pitting, onycholysis) support diagnosis
- Screen for psoriatic arthritis – 30% may develop joint disease
- Avoid abrupt steroid withdrawal – risk of rebound flare
【7】Challenging Questions
Q: “Is this contagious? I work in an office.”
A: “I understand your concern. Psoriasis is not contagious—it’s an immune condition, not an infection. You can safely interact with others. Let’s focus on managing your symptoms effectively.”
Q: “Do I need lifelong medication?”
A: “Psoriasis tends to be chronic, but many people manage it well with topical treatments and lifestyle adjustments. We’ll start with a safe and effective plan now, and adjust it depending on your response.”
【8】📝 SOAP Note
S: 42-year-old male with 3–4 month history of itchy, scaly rash on elbows and scalp. Initially thought to be dry skin, but no improvement with moisturizers. No systemic or joint symptoms. Concerned about contagiousness and chronicity. O: T 36.5°C, HR 82, BP 130/78, RR 16, SpO₂ 99% PE: Erythematous plaques with silvery scale on extensor elbows and posterior scalp. No joint findings or nail changes. A: # Suspected plaque psoriasis # No joint involvement at present # Significant psychosocial impact ddx): Psoriasis, seborrheic dermatitis, chronic eczema r/o): Tinea corporis (no central clearing), atopic dermatitis (no flexural pattern) → Presentation consistent with plaque psoriasis. Will begin topical management and monitor for joint symptoms or worsening skin lesions. P: - Topical corticosteroid (e.g., betamethasone dipropionate) for affected areas - Medicated shampoo for scalp (e.g., coal tar, salicylic acid) - Dermatology referral if no improvement in 4–6 weeks - Educate on chronic nature, triggers, and non-contagious nature - Monitor for arthritic symptoms (joint pain, morning stiffness)
Case 3 – Tricky Case:
【1】Doorway Information
- Age/Gender: 60-year-old female
- Chief Complaint: Progressive rash on hands and arms, muscle weakness
- Vital Signs: T 37.2°C, HR 86, BP 128/74, RR 18, SpO₂ 97% RA
【2】Structured History
Opening:
“My skin’s been changing—and now I can barely lift my arms.”
Shoreline:
“Tell me more about that?”
“It started with a reddish rash on the back of my hands about a month ago. Then I noticed more around my eyes and chest. Now I feel weak—especially when trying to comb my hair or lift things overhead.”
- Onset & Course: Rash began one month ago, weakness followed after 1–2 weeks, worsening gradually.
- Associated Symptoms: No fever, cough, or joint pain. Mild dyspnea on exertion.
- Mood / Function / Appetite / Sleep: Fatigued, decreased appetite, unintentional weight loss of a few kilos.
- Medical History / Medication:
- P: Hypertension
- A: NKDA
- M: Amlodipine
- H/I/T/S: Appendectomy in 20s; otherwise none
- FOSS:
- F: Father died of lung cancer at 65
- O: Menopause 10 years ago; two children
- S: Widowed, not currently sexually active
- S: Retired teacher; former smoker (20 pack-years); occasional alcohol
- Concerns & Questions: “Is this something serious? I looked online and now I’m worried it could be cancer…”
【3】Physical Examination
- Positive Findings: Gottron’s papules on MCP and PIP joints, heliotrope rash around eyelids, erythematous rash over upper chest (shawl sign), proximal upper limb weakness (shoulder abduction 3/5), mild exertional dyspnea
- Important Negative Findings: No joint swelling, no digital ulcers, no lymphadenopathy
- HEENT: Violaceous eyelids; normal oral mucosa
- Chest: Mildly reduced breath sounds at bases
- Abdomen: Soft, non-tender
- Neuro/MSK: Symmetric proximal muscle weakness; reflexes intact, no sensory deficit
【4】Differential Diagnosis (Top 3)
- Dermatomyositis (Most likely)
- Supporting: Heliotrope rash, Gottron’s papules, shawl sign, proximal weakness, weight loss
- Contradictory: None
- Polymyositis
- Supporting: Symmetric proximal weakness
- Contradictory: Lacks skin manifestations
- Paraneoplastic syndrome
- Supporting: Older age, weight loss, ex-smoker, dyspnea, FHx of lung cancer
- Contradictory: No known malignancy yet
【5】Clinical Reflection
“The rash pattern and weakness strongly suggest dermatomyositis—and her systemic symptoms raise red flags. Given her age and history, I need to investigate for an underlying malignancy.”
【6】Clinical Tips
- Muscle + Rash = Think Dermatomyositis
- Classic signs: Gottron’s papules, heliotrope rash, shawl sign
- Proximal symmetric weakness = myopathy
- Cancer screening is mandatory in adults with new-onset dermatomyositis
- Lab: CK, LDH, AST/ALT, ANA, myositis-specific antibodies (anti-Mi-2, TIF1-γ)
【7】Challenging Questions
Q: “Could this be cancer?”
A: “That’s an important question, and it’s something we need to consider. Dermatomyositis can sometimes be a clue that there’s something else going on inside the body. We’ll run the appropriate tests to find out and take it step by step together.”
Q: “Will I get my strength back?”
A: “With treatment, many people do improve. Early diagnosis and the right therapy can make a big difference. We’ll focus on both the skin and muscle symptoms, and monitor your progress closely.”
【8】📝 SOAP Note
S: 60-year-old woman presents with 1-month history of reddish rash on hands, now involving periorbital and upper chest areas, followed by progressive proximal muscle weakness. Reports fatigue, weight loss, and mild exertional dyspnea. Concerned about possible cancer. O: T 37.2°C, HR 86, BP 128/74, RR 18, SpO₂ 97% PE: Heliotrope rash, Gottron's papules, shawl sign, symmetric proximal muscle weakness (UE 3/5), mild decreased breath sounds bilaterally. No joint swelling or neuro deficits. A: # Suspected dermatomyositis # Paraneoplastic syndrome – rule out underlying malignancy # Unintentional weight loss and dyspnea ddx): Dermatomyositis, polymyositis, paraneoplastic dermatosis r/o): SLE (rash distribution atypical), myasthenia gravis (no ocular symptoms, no fluctuation) → Highly suspicious for dermatomyositis with possible neoplastic trigger. Needs full myositis workup and cancer screening. P: - Labs: CK, LDH, AST/ALT, ANA, anti-Mi-2, anti-TIF1γ - EMG and/or MRI of proximal muscles - Chest CT, age-appropriate cancer screening (mammography, colonoscopy, pelvic US) - Consider skin/muscle biopsy - Referral to rheumatology and dermatology - Start steroids after initial workup (prednisone ~1 mg/kg)
References
- UpToDate: Atopic dermatitis, Psoriasis, Dermatomyositis – Clinical features and management
- DermNet NZ. https://dermnetnz.org/
- Callen JP. Dermatomyositis. N Engl J Med. 2000;343(5):347–356.
- American Academy of Dermatology Guidelines on eczema and psoriasis
- National Psoriasis Foundation. https://www.psoriasis.org/
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