Derm Scalp, Head and Facial Skin Infections

Scalp

Androgenetic alopecia

• Treatment:
  • Minoxidil (topical) + oral finasteride
    • Best clinical evidence is for topical MINOXIDIL (2%-5%)
      
      • Prevents further progression
      • Leads to increase hair density & hair thickness
    • In male patients – can add oral finasteride 1mg – not indicated in patients with history of depression or sexual dysfunction
  • Hair Restoration Surgery
  • Hair transplant, scalp reduction surgery, or combo of both
  • Non surgical hair replacement – wigs, sprinkle hair, camouflage techniques, bonding
  • Low level lasers – PRP

Alopecia areata

• Etiology:
  • Black dot, exclamation mark hairs
  • pitting nails, sandpaper-like
• Treatment:
  • Intralesional corticosteroids (triamcinolone) usually self-limiting
    • No treatment option is appropriate for some patients, discuss risks vs benefits
    • Intralesional corticosteroid (triamcinolone acetonide or triamcinolone hexacetonide) injection is first-line therapy for adult patients with less than 50% scalp involvement.
    • Triamcinolone acetonide is used at concentrations from 2.5 to 10 mg/mL
  • Platelet-rich plasma (PRP)
  • Systemic corticosteroids
  • Topical minoxidil
  • Camouflage, wigs, and hairpieces

Lice (Pediculosis)

• 3 Types:
  • head lice (Pediculosis capitis)
    
    • found on the scalp, nape of the neck, and behind ears
    • MC children between 3 to 12
       
  • Body lice (pediculosis corporis)
    
    • start out on clothing or in beds, but move from those locations to people’s skin
      
    • recognized vector for transmission of typhus and trench fever, poor hygiene, and conditions of crowding
  • pubic lice (pthirus pubis)
    • (“crabs”) found on pubic hair and skin
      
    • associated with sexual transmission
• Presentation:
  • – itching
    
  • – irritability and difficulty sleeping
    
  • – excoriated lesions on scalp, ears, neck
• Transmission of Head Lice:
  • direct head to head contact with an infected person
    
  • indirect (fomite) transmission through combs, brushes
• Live Louse description:
  • 2-3 mm with 3 pairs of claw-like legs adapted for grasping hair (female a little bigger)
    
  • feeds 4 to 6 times/day
  • lice live: < 2 days
• Nits:
  • – shells containing eggs
    
  • – firmly attached to the hair shaft by a glue-like substance
    
  • – close to the scalp
    
  • – incubation period from laying eggs to hatching is 7-10 days
    
  • – often confused with dandruff
    
  • – feel like tiny knots on hair
  • nits live: up to 10 days
• Diagnosis:
  • direct visualization and identification of 1 live louse or nymph on the scalp
    
  • nits alone are not proof but they are easier to spot (can be inactive or treated disease)
• Treatment:
  • permethrin 1% rinse or cream +dispose of clothes = 1st line
    • – pyrethrins 0.3% (synergized with piperonyl butoxide)
      
    • – permethrin 1%
  • Benzyl Alcohol 5% – work through suffocation
  • Malathion 0.5%
    • Ovide – neurotoxin: inhibits cholinesterase in lice, causing respiratory paralysis and death
  • Ivermectin 0.5%
    • Sklice – neurotoxin: increases the permeability of cell membranes to chloride, resulting in hyperpolarization, paralysis, and death
  • Spinosad 0.9%
    • Natroba – neurotoxin: CNS excitation and involuntary muscle contractions produce paralysis and death
  • Lindane 1% 
    • neurotoxin: stimulates the nervous system of lice, causing seizures and death
       

Seborrheic Dermatitis

• Treatment:
  • shampoo with zinc/selenium alternated with ketoconazole shampoo

Telogen effluvium

• Def:
  • temporary hair loss due to the excessive shedding of resting or telogen hair after some shock to the system.
  • New hair continues to grow. 
  • Telogen hair is also known as club hair due to the shape of the root.
• Treatment:
  • *Iron (if deficient)

Tinea capitis

• Etiology:
  • fungal infection of the scalp
  • Most commonly seen in children ages 3-14
  • Generally more common among children of African descent.
  • Inflammatory, non-inflammatory, black dot and kerion
    
  • T. Tonsurans most common cause
• Transmission:
  • increased with decreased personal hygiene, overcrowding, and low socioeconomic status.

Head and Face

Actinic keratosis

• Etiology:
  • A strong indicator of chronic exposure to UV radiation.
  • Patients at high risk to develop nonmelanoma skin cancer.
  • Asymptomatic or tender (picking or burning sensation)
    
  • More easily “felt” than “seen”
    
  • May progress to invasive squamous cell carcinoma (SCC)
• Treatment:
  • For few scattered lesions:
    
    • •Cryotherapy with Liquid Nitrogen. Liq N2 is -195.8 C
    • •Surgical Therapy (physical destruction)
      
    • Less commonly used-deep chemical peels
  • For numerous lesions:
    
    • •Topical 5 Fluorouracil (5-FU), Aldara (imiquimod 5%), Zyclara (imiquimod 2.5%), Solaraze (diclofenac gel)
      
    • •PDT (photodynamic therapy with delta aminolevulinic acid)

Basal cell carcinoma

• Treatment:
  • Mohs surgery: excision with 1-2mm margins

Impetigo 

• Treatment:
  • +soaks and scrubbing +Topical bacitracin or mupirocin
• Multiple family member outbreak Treatment:
  • Oral ABX =cephalexin

Freckles/Lentigines

• Treatment:
  • Not needed but >>
    
  • 1. topical tretinoin
    
  • 2. tazarotene
    
  • 3. laser therapy
    
  • 4. cryotherapy

Keratoacanthoma (KA)

• Etiology:
  • Pseudo cancer, an isolated nodule that mimics SCC
    
• Diagnosis:
  • made by history and skin exam
    
  • Biopsy required for confirmation as the lesion is indistinguishable from SCC and CH
    
• Treatment:
  
  • Lesions may undergo spontaneous remission
    
  • Surgical excision is required to r/o skin cancer

Melanoma

Melasma/Chloasma

• Etiology:
  • sharp, well-defined Brownish pigmentation of the face during pregnancy;
    
  • hormone-induced
    
  • genetic
• Treatment:
  • Sun protection
    
  • *disappears after pregnancy

Oral candidiasis

• Etiology:
  • (pseudomembranous form, thrush)
    
  • Typical white palatal patches and plaques.
• Treatment:
  • First-line Clotrimazole 10-mg troches 5 times daily or miconazole 50-mg buccal tablets for 1 to 2 weeks
    
  • Alternative nystatin suspension 100,000 units/mL, 4 to 6 mL 4 times daily for 1 to 2 weeks
    
  • Refractory and resistant cases:
    • Moderate and severe cases may require fluconazole 100 to 200 mg oral daily for 1 to 2 weeks.
    • Itraconazole, posaconazole, voriconazole, and amphotericin B solutions and suspensions are alternatives for refractory or resistant disease.
  • For denture wearers, disinfection of dentures is an important adjunctive step to prevent reinfection

Perioral dermatitis

• Treatment:
  • **AVOID TOPICAL STEROIDS**
  • Give metronidazole gel 
  • +systemic ABX (cyclines)

Pseudofolliculitis barbae

• Def:
  • ingrown hairs or razor bump
    
  • males with coarse curly hair, pubic area
    
  • triggers immune cells

Seborrheic keratosis 

• Treatment:
  • -Liquid Nitrogen
  • -curettage 
  • -surgery

Squamous cell carcinoma

• Etiology:
  • Malignant tumor of keratinocytes arising in the epidermis, skin appendages, and other stratified squamous mucosae.
    
  • Often arise in pre-cancerous lesions
    
  • AK–> Bowen’s–> Squamous Cell Carcinoma
• Squamous cell carcinoma in situ:
  • Bowen’s disease
    
  • Lesions left untreated will progress to invasive squamous cell carcinoma
• Treatment:
  •  SCC in situ:
    • Topical Chemotherapy
      
      • 5-FU, Imiquimod cream
        
    • Cryosurgery
      
      • Highly effective. More aggressive freezing than for AK’s so scarring will usually result
        
    • Photodynamic Therapy (PDT)
      
      • Effective but cumbersome and painful
        
    • Surgical Excision
      
      • Offers the highest cure rate but has the highest chance of cosmetic disfigurement
  • SCC:
    • Surgical excision with primary closure- (grafts & flaps prn)
      
    • MOH’s indicated for dangerous sites ( same as for BCC)
      
    • Radiation if surgery contraindicated
      
    • Topical creams used in the treatment of superficial skin CA’s are not indicated in invasive cancers.

Tinea barbae

• Etiology:
  • Beard area of males most common area (more so than upper lip)
  • Formerly spread through contaminated razors at a barber
    
  • Transmission now- direct exposure to cattle horses and dogs
    
  • More common in ranchers and farmers
    
  • 2 main types: superficial and deep (kerion)
    
• Treatment:
  • Oral antifungal