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Dermatology Dr. Hussein A. Al -Sultany
201 9-20 20
Viral S kin I nfections

H erpesviruses

H erpesviruses belong to Herpesviridae which is a large family of DNA viruses .
There are eig ht distinct viruses in this family known to cause disease s in humans (human
herpes viruses (HHV)), include :

Virus t ype

Diseases
HHV -1 (HSV -1) Herpes Labialis.
HHV -2 (HSV -2) Herpes G enitalis.
HHV -3 (VZV) Chickenpox and Herpes Zoster (HZ) .
HHV -4 (EBV) Infectious M ono nucleosis .
HHV -5 (CMV) Infectious M ononucleosis -like syndrome.
HHV -6 Roseola Infantum .
HHV -7 Pityria sis Rosea .
HHV -8 Kaposi's Sarcoma .

Herpes S implex V irus (HSV) :

It has been separated into two types :
Type 1: are usually orofacial (herpes labialis ).
Type 2: are usually genital (herpes genitalis ).
The virus usually spread by direct contact.
Herpes viruses are not curable , a fter the episode of the primary infection, the virus may
become latent, possibly within nerve ganglia, but stil l capable of giving rise to recurrent
bouts of vesication ( recurrences or recrudescence s).
1- Primary infection :
A - Herpes labialis : the most common recognizable manifestation in children is an acute
gingivostomatitis , accompanied by malaise, headache, fever and cervical
lymphoadenopathy . Vesicles, soon turning into small ulcers, can be seen scattered over
the lips and mucous membranes. The illness lasts about 2 weeks.
B- Herpes genitalis : usually transmitted sexually, cause multiple and painful genital or
perianal vesicles which rapidly ulcerate.
2- Recurrent (recrudescent) infection :
The lesions usually recur at the same place.
A - H erpes labialis : usually on the lips and the vermilion border .
B- H erpes genitalis : usually on t he genital ia .

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Trigge ring factors:

A - H erpes labialis : fever, URTI (cold sores), ultraviolet radiation, menstruation , or stress.
B- H erpes genitalis : physical stress, emotional stress, steroids, menstruation,
imunossupression, and friction from sexual activity or tight clothe s
Clinical features: tingling, burning or even pain is followed within a few hours by the
development of erythema and clusters of tense vesicles (grouping arrangement ).
Crust ation occurs within 24 –48 h and the whole episode lasts about 2 weeks .
● Vesicles in recurrent infections differ from those in primary infections by : (1) smaller
size . (2) fewer number . (3) closer grouping . (4) the usual absence of constitutional
symptoms or lymphadenopathy, unless there is secondary bacterial infection.
Complications :
1- Herpes encephalitis or meningitis.
2- Disseminated herpes simplex.
3- Eczema herpeticum: widespread infections , usually occur in atopic dermatitis .
4- Secondary bacterial infection.
5- Recurrent dendritic ulcers leading to corneal scarring.
6- Erythema multiforme.
Treatment:
Topical:
A cyclovir cream or penciclovir cream, applied frequently , started as early as possible for
few days.
Topical antiseptic, sunscreens, lubricating creams may also be required.
Systemic:
Acyclovir is an antiviral drug that a cts as a specific inhibitor of herpesvirus DNA
polymerase . Famciclovir and valaciclovir can be used .
1- Primary infection:
acyclovir tablets 200 mg five times daily for 7 -10 days.
2- Recurrent infection:
A - Episodic treatment : if less than 6 recurrences p er year .
A cyclovir tablets 400 mg three times daily for 5 days.
B- Suppressive therapy : if more than 6 recurrences per year.
A cyclovir tablets 400 mg twice daily , for prolonged periods (6 months).
3- Sever disease or immunocompromised patient :
IV a cyclo vir 5-10 mg /kg three times daily for 7 -10 days .

V aricella -Z oster V irus (VZV):

Varicella (Chickenpox) :
It is the primary infection of VZV, i t is a highly contagious viral infections, transmission
occur via airborne droplets or contact with the vesicular fluid. Patients are contagious 2
day s before and 5 day s after onset of rash. The IP averages 2 weeks.
Presentation and course :
Prodromal symptoms (fever, chills, malaise, headache, and anorexia ) are followed by the
development of papules , which turn rapid ly into clear vesicles , which may become
pustul es , over the next few days the lesions crust and then clear, sometimes leaving
depressed scars.

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Lesions appear in crops , so l esions of different stages are present at the same time . The
lesions a re often i tchy, and are most profuse on the trunk (centripetal ). The v esicles may
also develop in the mucous membranes (especialy of the mouth).
An attack of chickenpox usually confers lifelong immunity.
Complications
1- Secondary bacterial infection .
2- Primary v aricella pneumonia (mostly in adult patients) .
3- Bacterial pneumonia, otitis media, and suppurative meningitis .
4- Haemorrhagic or lethal chickenpox in the immunocompromised.
5- Scarring.
Treatment :
1- Symptomatic relief : antipruritic lotions (e.g. cal amine), antipyretics (except aspirin),
and antihistamines.
2- Antibiotics: indicated for secondary bacterial infections.
3- Systemic a ntiviral (acyclovir 20 mg /kg , 5 times daily for 7 days ), indicated for :
A - Severe attacks .
B- Immunocompromised .
C - Patients 13 years of age or old er (more sever & more complicated disease ).
● Varicella vaccine (Varivax, Varilrix) is a live (attenuated) virus administered to protect
against chickenpox. It was recommended in 2006 as a part of the routine immunization
schedule in the US, not all countries provide the vaccine due to its cost.
Herpes Z oster (HZ) (Shingles ):
HZ is caused by VZV . An attack is a result of the reactivation of virus that has remained
dormant in a sensory root ganglion since an earlier episode of chickenpox .
The incidence of shingles is highest in old age, and in some conditions in which weaken
normal defense mechanisms.
Patients with zoster can transmit the virus to others in whom it may cause chickenpox
(if there is no previous attack).
Presentation and course :
Attacks usually start with a burning pain, soo n followed by erythema and grouped
vesicles (grouping arrangement ), scattered over a dermatome (dermatomal distribution );
commonly the thoracic segments or the ophthalmic division of the trigeminal nerve .
It may affect more than one adjacent derm atome.
The clear vesicles quickly become purulent, and over a few days burst and crust.
H emorrhagic or necrotic lesions may indicate an underlying immuno deficiency state.
● HZ is characteristically unilateral , and usually occurs once in life .
● Second episode, or bilateral infection of HZ is very unusual .
● Occasionally, before the rash has appeared, the initial pain is misdiagnosed as acute
appendicitis , renal colic , or m yocardial infarction (according to its site) .
Complications :
1- Post herpetic neuralgia : the most common complication, which is a p ersistent neuralgic
pain after the skin lesions have disappeared . Its risk increase with age and severity .
2- Dissimination: may occur in immunocompromised patients , devided into :
a- Cutaneous (more than 20 vesicles outside the affected dermatome).
b- V isceral (lung, liver, and brain involvement).
3- Motor nerve involvement, which has led to muscular paralysis .

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4- Secondary bac terial infection.

5- N ecrosis and scarring.
6- H Z ophthalmicus (HZ of the ophthalmic division of the trigeminal nerve ): can lead to
corneal ulcers and scarring.
7- Ramsay -Hunt’s syndrom : involvement of the geniculate ganglion, can lead to facial
nerve par alysis and auditory symptoms.
Treatment :
1- Systemic antiviral therapy: acyclovir 800 mg five times daily for 5-7 days, should be
given in the early stages of the disease (within the first 3 days ).
Indication s: (a) old patient (more than 50 years) . (b) very painful or sever case .
(c) immunosuppressed patient . (d) dissimination. (e) m otor nerve involvement .
(f) H Z ophthalmicus. (g) Ramsay -Hunt’s syndrom.
Topical antiviral agents is not effective in HZ .
2- Supportive ther apy: rest, analgesics and antipruritic lotions as calamine.
3- Antibiotic therapy: for s econdary bacterial infection.
4- Treatment of post -herpetic neuralgia: gabapentin, carbamazepine, amitriptyline, or
topical capsaicin cream.

Human Papilloma V irus (HP V )

HPV is a DNA virus , with m ore than 100 recogniz able sero types .
HPV infect the skin causing wart s, which transmitted by direct contact.
Types of wart s:
Many types of wart have been identified, varying in shape and site affected, as well as the
sero type of human papillomavirus , these include:
1- Common wart (Verruca vulgaris): aised with rough surface, most common on hands .
2- Flat wart (Verruca plana ): a small, smooth , flatte ned, skin -coloured or light brown .
Lesions are multiple, painless and mostly on a face of children .
3- Genital wart (Condyloma acuminat a): papillomatous cauliflower -like lesions, with a
moist macerated surface on the genitalia.
4- Filiform or D igitate wart : a thread - or finger -like wart, most commo n on the face.
5- Plantar wart : these have a rough surface, which protrudes slightly from the skin.
6- Periungual wart : warts that occurs around the nails.
7- Mosaic wart : a group of tightly clustered warts, commonly on the soles .
Course :
● Warts commonly occur in children and young adults, but they may appear at any age.
● Their course is highly variable; most resolve spontaneously in months, and others may
last years or a lifetime . Such spontaneous resolution, sometimes heralded by a pun ctate
blackening (black dots) caused by capillary thrombosis.
● Mosaic warts are slow to resolve and often resist all treatments.
● Warts persist and spread in immunocompromised patients ( especially with
lymphoreticular disease).
● Warts may spread by au toinoculation, scratching (ko ebner phenomenon) .
Complications :
1- Pain: some plantar warts are very painful.
2- Secondary bacterial infection.

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3- Malignant change: generally it is rare , but may occur in the following conditions:

A - Certain genital strai ns (16&18), predispose to cervical or penile ca rcinoma (SCC) .
B- In immunocompromised patients (as renal transplantation ),especially on exposed areas.
C- Epidermodysplasia verruciformis : a rare inherited disorder , in which there is a
impairment of cell -me diated immunity with universal wart infection .
Treatment of wart s:
1-Topical : caustic material (salicylic acid , lactic acid, or TCA) , imiquimode,
podophylline , or 5-Flourouracil .
2- Intralesional : 2% zinc sulphate , or interferon alfa.
3- Physical : curett age &/or electrodesication , cryotherapy , CO2 laser , or e xcision .
4- Systemic : oral zinc sulphate , cimetidine , retinoids , interferon , or BCG vaccination .
5- O thers , include:
A - A ntiviral therapy: recently cidofovir (Vestide) treatment is promising , it can be used
systemically (IV) or topically , or by intralesional injection , it is very expensive.
B- Treatment by suggestion : Many myths and some studies claiming that warts can be
effectively treated by suggestion .
Vaccination: prophylactic vaccination to prev ent (not treat) genital wart (6,11,16&18) .
Two types available: (1) Cervarix . ( 2) Gardasil .
Pox v irus
The poxviruses are double -stranded DNA viruses . They are the largest animal viruses and
can be seen with light microscopy . It have 3 main genuses : orthopox causing smallpox
which is eradicated since 1978, molluscipox causing MC, and parapox causing orf.
Molluscum Contagiosum (MC) :
Presentation and course :
The incubation period ranges from 2 to 6 weeks. Individual lesions are shiny , pearly or
pink in color , smooth surface, firm, dome shaped papule, averaging 3 -5 mm. A central
punctum, which may contain a cheesy core, gives the lesions their characteristic
umbilicated look. The most commonly involved sites are the face and the genital areas.
Multiple lesions are common , and o ften several members of one family are affected. They
may spread by autoinoculation, scratching (ko ebner phenomenon) , or touching a
contaminated fomites . Untreated lesions usually clear in 6 –9 months.
Treatment
● Treatment option s: curettage, cauterization, cryosurgery, cantharidin, imiquimod,
tretinoin, chemical solutions (phenol, lactic acid, TCA, or KOH), or CO2 laser.
● The antiviral agent cidofovir has recently been shown to effectively resolve molluscum
lesions (used eithe r intravenously or topically).
Orf :
Presentation and course :
The incubation period is 5 to 6 days. Lesions are pustular nodules with a violaceous or
erythematous surround. It can be transmitted to those handling infected animals (especially
the animal's head) . The condition clears up spontaneously in about a month.
Treatment : A topical antibiotic helps to prevent secondary infection; otherwise no active
therapy is needed .


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