Dermatology 2 Flashcards
Herpes: Two viruses
Herpes simplex virus
Herpes zoster virus
Herpes Simplex: Manifestations
Non-genital HSV infection (of the oral mucosa, the lips and of the skin)
Genital HSV infection (of the genitals, and the perianal area)
Herpes Zoster: Manifestations
Chickenpox
Shingles
Herpes: Characteristics
Either disease (HSV or HZV) can reactivate, and the severity of illness is dependent on the immune system of the host, that is, the weaker the immune system, the more severe the disease and the more extensive the lesions
Herpes Simplex: S/Sx
Causes a vesicular rash, (ulcerations on mucus membranes) which is painful
Herpes Simplex: Characteristics
Contagious by contact, and nearly all adults show some antibody activity whether or not they have ever had an outbreak
Prevention of transmission is helpful, active lesions are contagious
Herpes Simplex: Tx
- Uncomplicated outbreaks: valacyclovir 1000mg PO tid x 7 days
- Severe outbreaks: acyclovir 5-10mg/kg IV q8hrs
Chicken pox (Varicella zoster): Characteristics
- Chicken pox is much more common in children and now a vaccine is available, making it less frequently encountered
- Typically, epidemics have coincided with seasonal influenza, and is spread by airborne aerosol
- Older the Pt the more severe
Chicken pox (Varicella zoster): Time course
Incubates over 14 days, then a prodrome of aches/pains, fevers, headache, then the rash appears 2-3 days after
Chicken pox (Varicella zoster): Lesions
- The rash is characterized by multiple erythematous papules and vesicles on erythematous, edematous bases, so-called “dewdrops on a rose petal” or varying size
- Lesions also appear on the mucosa of the respiratory, GI and GU tracts causing symptoms as well
Chicken pox (Varicella zoster): Prognosis
- Can occasionally progress to an encephalitis or pneumonia, either one can be quite serious and is occasionally fatal
Chicken pox (Varicella zoster): Dx
Can be diagnosed clinically, by Tzanck smear, or by antibody screen
Chicken pox (Varicella zoster): Tx
No specific treatment is indicated for uncomplicated cases, but with complicated cases (nearly all adult cases):
- Valacyclovir 1000mg PO tid x 10 days, or Acyclovir 5-10mg/kg IV q8hrs
- Zoster immune globulin (ZIG)
Shingles: Characteristics
- Shingles is due to a reactivation of varicella zoster virus (VZV) within a person’s body
- The reactivation can be caused by a decrease in immune function or is sometimes idiopathic
- Any patient with a reactivation of VZV in any form, is contagious to those who are not immune to it (i.e. it will produce chicken pox, not shingles)
Shingles: Time course
Generally, there is a 2-4 day period of pain the area before the rash appears
Shingles: Lesions
The rash is erythematous vesicles that erupt along a dermatome, and then become confluent
Shingles:
- Valacyclovir 1000mg PO tid x 10 days
- If in CN V (Ramsay-Hunt syndrome), steroids are needed (can cause Bell’s Palsy)
- If affecting the cornea, usually ophthalmological consultation is needed, plus the above
- In severe immunocompromise, it can become disseminated, which requires:
- Acyclovir 10mg/kg IV q8hrs and very close monitoring while in the hospital for other opportunistic infection
Indication of disseminated zoster
Sign of HIV, cancer, or other serious illness
Terry’s nails: characteristics
Loss of the lunula
Proximal 2/3 of the nailbed is hypo pigmented
Distal 1/3 of the nailbed is hyperpigmented
Terry’s nails: Seen in
CHF, cirrhosis, hypoalbuminemia
Blue nails: Seen in
Chronic use of antimalaria drugs, minocycline
Hemachromatosis
Wilson’s Dz
Yellow nail syndrome: Seen in
Pleural effusions, lymphoedema
Bronchiectasis in 40% of Pts
*It involves all the nails
Splinter hemorrhages: characteristics
Brown or red streaks along the nailbed
Splinter hemorrhages: Seen in
Trauma to the nail
microemboli as seen in endocarditis
Beau’s lines: characteristics
Horridontal depressions across the nail plate
Transient arrest of nail growth
Beau’s lines: seen in
Pts on chemotherapy
Koilonychia: characteristics
aka “spoon nails”
Caused by softening and thinning of the nail plate
Koilonychia: seen in
Iron deficiency anemia (long term anemia)
Raynaud’s Dz
hemachromatosis
inherited autosomal dominance disorder
Clubbing: characteristics
Angle btw the nail fold and the nail plate exceeds 180 degrees
Tissue btw nial and the underlying bone has a spongy quality
Clubbing: seen in
chronic hyposia or inherited condition
Brown nails: characteristics
brown line seen in the nail plate
Brown nails: seen in
Addison's Dz Hemachromatosis Gold Thx Chronic arsenic poisoning (exterminator, lab tech) Melanotic nevus Malignant melanoma
Onychomycosis: characteristics
Fungal infection
Tx: topical Tx, PO terbinafine if topical Tx fails
Paronychia: characteristics
Proximal nail fold infection
Painful, swollen, erythematous and warm just adjacent to the nail
Sometimes 2/2 cuticles cut
