Viral infections Objectives: 1- Describe the clinical features and treatment of herpes simplex, chicken pox and viral warts 2- differentiate genital herpes from other causes of genital ulcers. 3- describe the clinical features and lines of treatment of pox virus infections. 4- describe the clinical features of measles and rubella

Herpes simplex Cause: herpes virus hominis, DNA virus. HSV I: mostly oral, transmitted by saliva HSV II: mostly genital transmitted by sex Virus entry primary infection latent infection recurrent attacks

Clinical features *Primary type I: usually asymptomatic, children. Symptomatic gingivostomatitis-vesicles and erosions- 2 weeks keratitis whitlow *Primary type II: genital vesicles and painful erosions

Recurrent attacks (type I): Herpes labilais or cold sore: Recurrent vesicles pustules erosions in the lips and near skin Ppt. factors: sunlight, menstruation, viral and bacterial infections. recurrent attack usually last 1 week.

Recurrent type II: *Recurrent genital ulcers affecting the penis, vulva, vagina, anus. *type II recur more frequent than type I * It is a common STD *represent a bad stigma with guilt feeling because of its persistence for many years.

complications Meningitis Encephalitis Disseminated inf. Secondary impetigo Corneal ulceration

Treatment Primary: Mild cases: rest, symptomatic, acyclovir 200mg 5 times daily for 10 days. Disseminated inf. In immunocompromised : intravenous acyclovir 5-10mg/ kg 8 hourly recurrent attacks: suppressive therapy Acyclovir 400mg twice daily Acyclovir not eradicate the HSV from the ganglia, but decrease the recurrence

Varicella V-Z virus. Transmission: direct contact and respiratory Prodromal symptoms: flu like Pink papules vesicles pustules crusted erosions Centripetal distribution Treatment: symptomatic, acyclovir for adults, severe cases and immunocompromised

Herpes zoster Caused by reactivation of V-Z virus acquired from previous chicken pox inf. V-Z virus latent in the cranial or dorsal root ganglia, its reactivation herpes zoster at the dermatome of corresponding nerve Usually its risk increase with age and low immunity

Clinical features Unilateral dermatomal pain for 3-5 days vesicles ulcerations. Last 2-6 weeks according to the age Sites of involvement: thoracic, cervical, trigeminal, lumbosacral

Complications Secondary bact. Inf. Corneal ulceration in ophthalmic zoster Motor nerve involvement Post herpetic neuralgia

Treatment Mild cases: rest, symptomatic Severe cases, ophthalmic zoster, low immunity acyclovir within 2-3 days analgesics, antidepressants

Viral warts Cause: HPV, more than 60 subtypes Transmission: direct contact and sex. Usually affects young people Immune deficiency extensive warts Type 16 and 18 cause cervical ca.

Clinical features Common warts ( verruca vulgaris): single or multiple papules with rough surface. Usually affect the hands, but can appear anywhere. Plantar warts: rough slightly raised papules. Plane warts: slightly raised skin colored- grey- pink smooth papules. Face and hands

Anogenital warts (condylomata acuminata) Affects skin and m.m. of the genital area. Papillomatous or cauliflower lesions D.Dx: Condylomata lata: flat papules, other features of secondary syphilis.

Treatment Local therapy: * Keratolytics: 12-20% salicylic acid * caustic agents: TCA for genital warts * cytotoxics: 5-FU for plane warts. podophylline for genital warts * Surgical: curretage, electrocautery, cryotherapy * immunomodulators: imiquimod for plane and genital warts * Retinoic acid: for plane warts

Systemic therapy For extensive warts Zinc sulfate, BCG vaccine, retinoids

Pox virus infections Molluscum contagiosum * Pox virus, transmitted by direct contact and sex * Clinical features: I.P. 2-6 weeks Shiny white or pink papule with central punctum in some cases. * usually disease of children, especially affects the face. * In adults involvement of the genital area indicates STD.

treatment Squeezing, curretage, cryotherapy, cautery, phenol puncture, retinoic acid

Orf

orf Caused by parapox v. Transmitted from sheep. I.P. 1 week Firm papule pustular nodule Clear in about 6 weeks spontaneously. No treatment required.

Measles Paramyxovirus, droplet transmission. I.P. 10 days Catarrhal stage:2 days of fever, running nose, red eyes, then photophobia and koplik’s spots Days 3-4 maculopapular rash covering the body in 3 days Days 6-7 days fever and rash subside fever and rash.

complications Pneumonia, keratitis, otitis media, encephalitis, weight loss Treatment Symptomatic, antibiotics for secondary bact. Inf.

Rubella (German measles) Caused by toga virus, droplet inf. I.P. 18 days. Less severe than measles, trivial in children, more severe in adults. Prodromal symptoms with suboccipital LAP Fine maculopapular rash covering the body in one day and disappear in the 3 rd day.

AIDS Caused by HIV, which target the CD4 T cells Skin manifestations of AIDS *Tumors: kaposi sarcoma, extensive with systemic involvement * dermatitis: seborrheic derm. * infections: opportunistic inf. ex candidiasis, severe HSV and HZV.

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Summary Primary herpetic gingivostomatitis…. Children Recurrent orolabial herpes… children and adults. Recurrent genital herpes ….guilt feeling. Varicella: polymorphic rash, centripetal H. zoster: severity is age dependent. viral warts: verrucous surface, usu. Self limited

Measles: toxic, maculopapular rash and fever Rubella: milder than measles Molluscum contagiosum: Easily treated. Orf: sheep. باجة