Module 4: Case Studies

Question 1

ow would you describe the skin lesions of Mrs SJ?

Answer 1

Well-defined erythematous plaques with silvery-white scales on the arms and legs.

Question 2

What is the most likely diagnosis and why?

Answer 2

Irritant contact dermatitis

Exposure to irritants at work (factory chemicals, detergents, allergens)

Localized rash on exposed areas (arms and legs)

Associated itching and discomfort

Question 3

What is a possible differential diagnosis?

Answer 3

Psoriasis

Question 4

What features support psoriasis as a differential?

Answer 4

Chronic, well-demarcated plaques

Silvery-white scaling

Commonly affects extensor surfaces

Question 5

How should Mrs SJ be treated and why?

Answer 5

Discontinue Tetmosol soap if irritating

Medium-potency topical corticosteroid (e.g., hydrocortisone 1%, betamethasone) to reduce inflammation

Emollients / moisturizers to restore the skin barrier

Oral antihistamines (cetirizine, loratadine) for itch relief

Avoid triggers (work-related chemicals, latex gloves, friction)

Question 6

What should Mrs SJ know about prognosis?

Answer 6

Good prognosis if triggers are avoided and treatment is followed

Recurrent symptoms may occur with chronic exposure

Question 7

What are common aggravating factors?

Answer 7

Work-related chemical exposure

Harsh soaps or detergents

Scratching (risk of secondary infection)

Sweating and friction

Question 8

What advice should be given?

Answer 8

Identify and avoid irritants

Moisturize regularly

Seek follow-up if symptoms persist or worsen

Question 9

In Tinea Corporis (Ringworm), how would you describe the morphology of Mr JM’s rash and the key clinical findings?

Answer 9

Large, well-demarcated, erythematous, scaly plaques with a serpiginous border

Central clearing, suggesting an annular or ring-like pattern

Prominent scaling at the edges, typical of superficial fungal infections

Extremely pruritic (itchy), a key symptom

Location: Involves the hip, possibly extending to other areas

Question 10

What is the likely diagnosis for Mr JM and why?

Answer 10

Tinea Corporis (Ringworm)

Classic annular lesion with raised, scaly borders and central clearing

Persistent, worsening symptoms over 6 months despite corticosteroid use

Severe pruritus, common in dermatophyte infections

No response to fluocinolone (corticosteroids can worsen fungal infections)

Risk factors: Type 2 diabetes and possible immunosuppression

Question 11

What are possible causes and contributing factors for Tinea Corporis (Ringworm) in Mr JM?

Answer 11

Fungal infection: Dermatophytes such as Trichophyton rubrum or T. mentagrophytes

Diabetes mellitus: Impaired immunity and poor glycaemic control favors fungal growth

Prolonged topical corticosteroid use (fluocinolone): Can suppress inflammation but worsen fungal infection (Tinea incognito)

Obesity / excessive sweating: May contribute to fungal proliferation

Environmental exposure: Contaminated clothing, gym equipment, close contact with infected individuals or animals

Question 12

What tests could help diagnose Tinea Corporis (Ringworm) in Mr JM?

Answer 12

Fungal culture (Sabouraud’s agar): Identifies exact fungal species

Blood glucose / HbA1c: If diabetes control is uncertain, as poor control increases infection risk

Question 13

What information and advice would you give Mr JM about Tinea Corporis (Ringworm)?

Answer 13

Cause: Likely a fungal skin infection worsened by steroid use

Contagious: Avoid sharing towels, clothing, or bedding

Hygiene: Keep skin dry, wear loose cotton clothing, change clothes frequently

Diabetes management: Poorly controlled diabetes can worsen infections

Medication: Stop using fluocinolone (steroids), as they worsen fungal infections

Question 14

What is the first-line treatment for mild to moderate Tinea Corporis?

Answer 14

Topical antifungals

Clotrimazole 1% cream, applied twice daily for 2–4 weeks

Apply beyond visible lesions by ≥2 cm to prevent recurrence

Continue for at least 2 weeks after lesion resolution

Question 15

What systemic treatments are used for severe or refractory Tinea Corporis?

Answer 15

Oral Terbinafine: 250 mg daily for 2–4 weeks (first-line)

Oral Itraconazole: 100–200 mg daily for 1–2 weeks (alternative)

Fluconazole: 150–200 mg once weekly for 4 weeks

Monitor liver function if prolonged treatment is needed

Question 16

What adjunctive measures help prevent recurrence of Tinea Corporis?

Answer 16

Antifungal powders (e.g., clotrimazole powder) in socks and shoes

Disinfect personal items: clothing, bedding, towels

Improve diabetes control to reduce susceptibility

Question 17

In Irritant Contact Dermatitis (ICD), how would you describe the morphology of Ms AB’s lesions?

Answer 17

Blistering lesions on the hands

May include redness, swelling, and scaling

Acute onset, often painful or burning

Question 18

What is the likely diagnosis for Ms AB and why?

Answer 18

Irritant Contact Dermatitis (ICD)

Sudden onset of symptoms (acute reaction to irritant)

Previous similar episodes (repeated exposure)

Occupation as a cleaner (high exposure to detergents, chemicals, frequent handwashing)

Symptoms: Burning and itching (chemical irritation is more acute, whereas allergic contact dermatitis is usually delayed)

Question 19

What factors contribute to Irritant Contact Dermatitis (ICD) in Ms AB?

Answer 19

Frequent handwashing with soaps or aqueous cream

Exposure to cleaning chemicals and detergents

Occupational role with repeated exposure

Previous episodes, indicating cumulative irritation

Skin barrier disruption from dryness or friction

Question 20

How would you manage Irritant Contact Dermatitis (ICD) in Ms AB?

Answer 20

Avoid or minimize exposure to irritants (gloves, protective equipment)

Stop using aqueous cream if irritating, or use gentle soap substitutes

Topical corticosteroids (e.g., hydrocortisone 1%) for inflammation

Emollients / moisturizers to restore the skin barrier

Oral antihistamines for itching if needed

Educate about proper hand care and frequent moisturizing

Question 21

What advice should be given for Irritant Contact Dermatitis (ICD)?

Answer 21

Good prognosis if exposure to irritants is reduced and treatment followed

Avoid scratching to prevent secondary infection

Use protective gloves at work

Moisturize hands regularly

Seek follow-up if symptoms persist or worsen

Question 22

In Irritant Contact Dermatitis (ICD), how would you describe Ms AB’s lesions?

Answer 22

Blistering lesions on the hands

Redness, swelling, and scaling

Acute onset, painful or burning

Question 23

What is the most likely diagnosis for Ms AB and why?

Answer 23

Irritant Contact Dermatitis (ICD)

Sudden onset (acute reaction)

Recurrent episodes (repeated exposure)

Occupation as a cleaner (frequent exposure to detergents and chemicals)

Symptoms: burning and itching (typical of chemical irritation)

Question 24

What are possible causes of Irritant Contact Dermatitis (ICD) in Ms AB?

Answer 24

Harsh cleaning chemicals: detergents, disinfectants, bleach

Frequent handwashing: removes natural skin oils

Gloves: latex or powdered gloves if used improperly

Aqueous cream: contains sodium lauryl sulfate, may worsen irritation with prolonged use

Question 25

What further history could help confirm ICD?

Answer 25

Specific products used at work: cleaning agents, gloves, sanitizers Glove use: material, frequency, trapped moisture Symptom pattern: improvement on weekends/holidays suggests work-related exposure Personal or family history of atopic eczema or allergies Household exposures: detergents, dishwashing soap, childcare activities

Question 26

What advice should be given for Irritant Contact Dermatitis (ICD)?

Answer 26

Avoid irritants: non-irritating hand soap, avoid harsh cleaning products Proper glove use: non-latex, powder-free gloves with cotton liners Moisturize frequently: fragrance-free emollients (petroleum jelly, thick creams) Switch from aqueous cream to a soap-free, pH-balanced cleanser Occupational adjustments: alternative cleaning agents or protective measures

Question 27

How should ICD be treated, and why

Answer 27

Reduce inflammation and discomfort: - Medium to high potency topical corticosteroids (e.g., betamethasone 0.05%) short-term - Cold compresses to soothe burning - Oral antihistamines (cetirizine, loratadine) if itching disrupts sleep or daily activities Protect and restore skin barrier: - Thick emollients (Eucerin, Cetraben, Vaseline) applied regularly, especially after washing Prevent recurrence: - Identify and avoid workplace irritants - Wear gloves properly with cotton liners - Referral to occupational health if symptoms persist

Question 28

What is the diagnosis for Mrs SJ and why?

Answer 28

Shingles (Herpes Zoster) Localized, unilateral distribution following a dermatome Vesicular rash with severe burning or lancinating pain History of recent oral thrush and weight loss suggests possible immunosuppression

Question 29

In Shingles (Herpes Zoster), how would you describe the morphology of Mrs SJ’s lesions?

Answer 29

Dermatomal distribution (affects back and right flank, crosses midline rarely) Erythematous base with grouped vesicles Surrounding skin is inflamed Accompanied by lancinating pain

Question 30

What is the causative agent of Shingles (Herpes Zoster)?

Answer 30

Varicella-Zoster Virus (VZV)

Question 31

What further investigations would you request and why in Shingles (Herpes Zoster)?

Answer 31

HIV serology, CD4 count, viral load – to check for immunosuppression HbA1c – to assess for diabetes, which can contribute to immunosuppression

Question 32

How would you treat Shingles (Herpes Zoster) in Mrs SJ?

Answer 32

Acyclovir: ideally within 72 hours of eruption; can be started later in immunosuppressed patients Pain management / post-herpetic neuralgia prevention: - NSAIDs - Amitriptyline, carbamazepine, or gabapentin - Start amitriptyline early if pain is severe - Referral if eye involvement or extensive rash