Integumentary Function

Full Answer Section

• Stress: Psychological stress (emotional, physical) is a significant and common trigger for many individuals with psoriasis. The neuro-immune axis plays a role, with stress hormones influencing immune cell function.
• Skin Injury (Koebner Phenomenon): Trauma to the skin, such as cuts, scrapes, burns, insect bites, vaccinations, or even aggressive scratching, can lead to new psoriatic lesions developing at the site of injury.
• Medications: Certain drugs can induce or worsen psoriasis. Common culprits include:
  • Beta-blockers (used for hypertension, heart conditions)
  • Lithium (for bipolar disorder)
  • Antimalarials (e.g., chloroquine, hydroxychloroquine)
  • NSAIDs (Nonsteroidal Anti-inflammatory Drugs)
  • Oral corticosteroids (especially withdrawal of systemic corticosteroids, which can trigger pustular or erythrodermic psoriasis)
  • Interferons
  • TNF-alpha inhibitors (paradoxically, can induce paradoxical psoriasis in some patients).
• Alcohol Consumption: Heavy alcohol intake can exacerbate psoriasis, particularly in men, and can interfere with the effectiveness of some treatments.
• Smoking: Tobacco use is a known risk factor for developing psoriasis and can worsen disease severity.
• Weather Changes: Cold, dry weather typically worsens psoriasis, while warm, sunny weather often improves it (due to UV exposure).
• Hormonal Changes: Puberty, pregnancy, and menopause can influence psoriasis severity, though the effect is variable among individuals.
• Obesity: Is associated with increased severity of psoriasis and can make treatment more challenging.

Different Clinical Types of Psoriasis:

Psoriasis manifests in several distinct clinical forms:

1. Plaque Psoriasis (Psoriasis Vulgaris):

   • Most Common: Accounts for about 80-90% of cases.
   • Characteristics: Symmetrically distributed, well-demarcated, erythematous (red) plaques covered with silvery-white scales. Lesions can vary in size.
   • Common Locations: Extensor surfaces (elbows, knees), scalp, lower back, and nails. Itching is common. K.B.'s initial diagnosis and current generalized outbreak align with this type.

2. Guttate Psoriasis:

   • Characteristics: Numerous small (0.5-1.5 cm diameter), "drop-like," salmon-pink lesions, often covered with fine scales.
   • Common Locations: Trunk and proximal extremities.
   • Trigger: Often appears suddenly, 2-3 weeks after a streptococcal (strep throat) infection, especially in children and young adults.

3. Inverse Psoriasis (Flexural Psoriasis):

   • Characteristics: Smooth, red, shiny lesions without typical scaling. The skin folds protect the scales from flaking off.
   • Common Locations: Skin folds (intertriginous areas) such as armpits, groin, under breasts, and in the navel.
   • Complications: Prone to irritation from sweating and friction, and secondary fungal or bacterial infections. K.B.'s groin involvement suggests this could be part of her generalized flare.

4. Pustular Psoriasis:

   • Characteristics: Appears as white pustules (blisters filled with non-infectious pus) surrounded by red skin. Not contagious.
   • Subtypes:
     • Generalized Pustular Psoriasis (GPP) / Von Zumbusch Psoriasis: A rare, severe, and potentially life-threatening form with widespread pustules, fever, chills, fatigue, and rapid progression. Requires immediate medical attention. Often triggered by withdrawal of systemic corticosteroids.
     • Localized Pustular Psoriasis: Confined to specific areas, such as palms and soles (palmoplantar pustulosis).

5. Erythrodermic Psoriasis:

   • Rarest and Most Severe: Affects nearly the entire body surface (>90%), causing widespread redness, severe scaling, itching, pain, and swelling.
   • Complications: Can disrupt the body's temperature regulation, fluid balance, and barrier function, leading to hypothermia, dehydration, and increased risk of infection. It is a medical emergency.

6. Psoriatic Arthritis:

   • Associated Condition: Not a skin type, but a chronic inflammatory arthritis that affects about 30% of individuals with psoriasis.
   • Characteristics: Can affect any joint, including fingers, toes, spine, and large joints. Symptoms include joint pain, stiffness, swelling, fatigue, and nail changes.

2. Treatment Approaches for Psoriasis and K.B.'s Relapse

There are several types of treatments for psoriasis, chosen based on severity, type, location, patient preferences, and comorbidities.

Types of Treatments:

1. Topical Therapies:

   • Corticosteroids: (e.g., clobetasol, halobetasol, betamethasone) – Anti-inflammatory and antiproliferative. Available in various strengths (low to super-high potency). K.B. initially responded well to high-potency topical corticosteroids.
   • Vitamin D Analogues: (e.g., calcipotriene, calcitriol) – Slow down skin cell growth. Can be used alone or in combination with corticosteroids.
   • Calcineurin Inhibitors: (e.g., tacrolimus, pimecrolimus) – Immunomodulators, useful for sensitive areas like face, folds, and groin due to lower risk of skin atrophy compared to steroids. Relevant for K.B.'s groin involvement.
   • Retinoids: (e.g., tazarotene) – Vitamin A derivatives, normalize skin cell growth.
   • Coal Tar: Reduces inflammation and scaling.
   • Anthralin: Reduces inflammation and normalizes cell growth, but can stain skin/clothing.
   • Salicylic Acid: Keratolytic, helps remove scales, often used with other topicals.

2. Phototherapy:

   • UVB (Narrowband UVB - NBUVB; Broad-band UVB - BBUVB): Controlled exposure to specific wavelengths of ultraviolet B light. Slows down skin cell growth and reduces inflammation. Effective for moderate to severe plaque psoriasis.
   • PUVA (Psoralen plus UVA): Patient takes psoralen (a photosensitizing drug) followed by exposure to ultraviolet A light. More potent but has higher risks (skin aging, cataracts, skin cancer).

Sample Answer

K.B.'s Psoriasis Case Study

1. Most Common Triggers for Psoriasis and Different Clinical Types

Most Common Triggers for Psoriasis:

Psoriasis is a chronic autoimmune skin condition characterized by an accelerated turnover of skin cells. While its exact cause is complex and involves genetic predisposition, various environmental and internal factors can trigger its onset or exacerbate existing lesions (flare-ups). The most common triggers include:

• Infections:
  • Streptococcal infections: Especially Group A Streptococcus (strep throat), are a well-known trigger for guttate psoriasis, particularly in children and young adults.
  • Other infections like upper respiratory tract infections, HIV, or Staphylococcus aureus can also trigger flares.