CLT Skin Conditions & Pathology for Light Therapy 2 — Questions and Answers
Question 1: What is post-inflammatory hyperpigmentation (PIH) and which clients are most at risk?
- Excess melanin deposited after skin inflammation, most common in Fitzpatrick Types IV–VI (Correct answer)
- Redness that persists after UV sunburn, most common in fair-skinned individuals
- Temporary skin lightening after aggressive exfoliation treatments
- Scarring caused by laser treatments on all skin types equally
Correct answer: Excess melanin deposited after skin inflammation, most common in Fitzpatrick Types IV–VI
PIH occurs when inflammation triggers melanocytes to overproduce melanin, and darker skin types are most susceptible due to more reactive pigment-producing cells.
Question 2: A CLT notices a client has a lesion with irregular borders, multiple colors, and a diameter greater than 6mm on their back. What is the most appropriate action?
- Refer the client to a dermatologist immediately before proceeding with any treatment (Correct answer)
- Document the lesion and treat the surrounding area only
- Photograph the lesion and monitor it over subsequent sessions
- Apply red light therapy directly to the lesion to promote cellular repair
Correct answer: Refer the client to a dermatologist immediately before proceeding with any treatment
The ABCDE criteria (Asymmetry, Border, Color, Diameter, Evolving) describe features of potential melanoma, requiring urgent dermatology referral before any light therapy.
Question 3: What is the Koebner phenomenon and why is it important for CLT practice?
- New skin lesions appearing at sites of trauma or injury, relevant when treating psoriasis or vitiligo clients (Correct answer)
- Skin darkening that occurs after sun exposure in previously treated areas
- Spontaneous remission of a skin condition without treatment
- Increased sensitivity to light that develops after initial phototherapy sessions
Correct answer: New skin lesions appearing at sites of trauma or injury, relevant when treating psoriasis or vitiligo clients
The Koebner phenomenon means that trauma—including from treatment equipment contact—can trigger new lesions in clients with psoriasis, vitiligo, or lichen planus.
Question 4: Which inflammatory skin condition is characterized by intense itching, dry skin, and a chronic relapsing course, and may be managed with narrowband UVB light therapy?
- Atopic dermatitis (eczema) (Correct answer)
- Seborrheic dermatitis
- Contact dermatitis
- Tinea corporis
Correct answer: Atopic dermatitis (eczema)
Atopic dermatitis is a chronic inflammatory condition with a strong genetic and immune component, and narrowband UVB phototherapy is an effective second-line therapy for moderate-to-severe cases.
Question 5: Why is it important for a CLT to know whether a client has a history of herpes simplex virus (HSV) before light therapy?
- Certain light therapies can trigger HSV reactivation (cold sores or genital herpes outbreaks) (Correct answer)
- HSV is a contraindication for all forms of light therapy permanently
- HSV history changes the Fitzpatrick skin type classification
- Light therapy cures HSV and should be promoted as a treatment option
Correct answer: Certain light therapies can trigger HSV reactivation (cold sores or genital herpes outbreaks)
UV and laser light exposure can trigger HSV reactivation in latent carriers, so prophylactic antiviral medication may be needed before certain light therapy procedures.
Question 6: What characterizes melasma and which light therapy approach requires extra caution when treating clients with this condition?
- Symmetrical facial hyperpigmentation triggered by hormones/UV; aggressive laser or IPL can worsen it (Correct answer)
- Superficial fungal infection requiring targeted antifungal phototherapy
- Vascular lesion best treated with high-intensity pulsed light without restrictions
- Bacterial overgrowth of the skin treated safely with high-fluence blue light
Correct answer: Symmetrical facial hyperpigmentation triggered by hormones/UV; aggressive laser or IPL can worsen it
Melasma is hormonally driven pigmentation that can be significantly worsened by heat and light, requiring low-energy, carefully controlled treatments.
CLT Skin Conditions & Pathology for Light Therapy 2
What is post-inflammatory hyperpigmentation (PIH) and which clients are most at risk?