Vesicular Rash Presented by: Dr.Fatimah Al Dubisi Pediatric infectious Diseases Consultant Heah Infection Control Division

Definition of vesicle

Herpes simplex Virus: Herpesvirus Family. Double-stranded DNA genome. Types of HSV: 1- HSV type 1(HSV-1): Causes recurrent oral infections. 2- HSV type 2 (HSV-2): Causes recurrent genital infections.

Mode of Transmission: Direct contact between mucocutaneous surfaces. HSV 1, from contact with contaminated oral Secretions. HSV 2, most commonly results from anogenital contact.

Pathogenesis:

Begins at a cutaneous portal of entry such as the oral cavity, genital mucosa, ocular conjunctiva, or breaks in keratinized epithelia. Virus replicates locally, herpetic vesicles and ulcers. Virus also enters nerve endings and spreads beyond the portal of entry to sensory ganglia. The progeny virions are sent via back to the periphery, where they are released from nerve endings and replicate further in skin or mucosal surfaces.

Pathogenesis: Cont.. All infected individuals harbor latent infection and experience recurrent infections, which may be symptomatic or may go unrecognized. It is periodically contagious.

- Primary infection - Latent Phase - Secondary infection ( reactivation )

Primary infection: Occurs in individuals who have not been infected previously with either HSV-1 or HSV-2 Reactivation ( recurrence): Occurs in individuals previously infected with 1 type of HSV (e.g., HSV-1) Latent Phase: In active phase of the virus, no replication ( no clinical symptom )

Clinical manifestation: Herptic jenjeovostomatitis

Clinical manifestation: 1-Acute Oropharyngeal Infections (Herpetic jenjeovostomatitis) Common in children 6 months to 5 years Sudden onset, painful vesicles appears in the mouth. Drooling, refusal to eat or drink, and fever of up to °C. Tender submandibular, submaxillary, and cervical lymphadenopathy is common. Resolves in 7-14 days. In older children and adolescents the initial HSV oral infection may manifest as pharyngitis and tonsillitis.

Clinical manifestation: Herpes Labialis:

Clinical manifestation: 2- Herpes Labialis: Most common manifestation of recurrent HSV-1 infections. Fever, blisters, or cold sores, The most common site: lip, sometime the nose, chin, cheek, or oral mucosa. Burning, tingling, itching, or pain 3-6 hr before the development of the lesion Complete healing without scarring occurs within 6-10 days.

Clinical manifestation: 2- Cutaneous Infections: Herpes whitlow

Clinical manifestation: 2- Cutaneous Infections: Result of skin trauma with development of some abrasions and exposure to infectious secretions. Pain, burning, itching, or tingling often precedes the eruption. Multiple discrete lesions and involves a larger surface Healing without scarring in 6-10 days. Regional LAP may occur but systemic symptoms seldom do.

Clinical manifestation: 2- Cutaneous Infections: Cont.. Herpes whitlow is a term generally applied to HSV infection of fingers or toes Unlike other recurrent herpes infections, recurrent herpetic whitlows are often as painful as the primary infection Cutaneous HSV infections can be severe or life threatening in patients with disorders of the skin such as eczema (eczema herpeticum), pemphigus, burns.

Clinical manifestation: Ocular Infections ( Herpetic Keratitis)

Clinical manifestation: 3- Ocular Infections May involve the conjunctiva, cornea, or retina. May be primary or recurrent. Conjunctivitis or keratoconjunctivitis Usually unilateral often associated with blepharitis and tender preauricular lymphadenopathy. ( Herpetic Keratitis): corneal ulcer is rare, described as appearing dendritic, but can lead to serious complication; scarring, and corneal perforation.

Clinical manifestation: Central Nervous System Infections

Clinical manifestation : Extensive herpes in immune compromised

Perinatal ( neonatal )Infections:

Perinatal Infections: Neonatal herpes is an uncommon but potentially fatal infection. Transmission occurs during delivery, although it is well documented even with cesarean delivery with intact fetal membranes. Portals of entry are the conjunctiva, mucosal epithelium of the nose and mouth, and breaks or abrasions in the skin that occur with scalp electrode use or forceps delivery

Diagnosis: Mainly clinical. Required in some condition like life threatening, genital infections. Samples; Blood, vesicular fluid, CSF, eye swab. can be done by: HSV PCR HSV serology ( IgG and IgM) HSV Ag detection by Direct Fluorescent test ( DFA) Viral Culture; done only in special lab.

Management : Supportive management ( Fluid, pain medication) Acyclovaire, to be started as erealy as possible ( within 24 – 48 hours). Duration of the acyclovaire depends on the site of infection

Varicella-Zoster Virus Infections:

Varecilla- Zoster Virus ( VZV): Herpesvirus Family Double-stranded DNA genomes Infection can be primary, latent, and recurrent infections.

Transmission:

Primary infection (varicella, Chicken Box) ) VZV is transmitted in oropharyngeal secretions and in the fluid of skin lesions either by airborne spread or through direct contact. Inoculation of the virus onto the mucosa of the upper respiratory tract and tonsillar lymphoid tissue. Incubation period is 10- to 21-day

Primary infection: ( Chicken Box) Acute febrile rash illness, Variable severity but is usually self limited. Prodromal symptoms may be present, particularly in older children and adults, fever, malaise, anorexia, headache, and mild abdominal pain may, hours before the rash appears. systemic symptoms usually resolve within 2-4 days after the onset of the rash

Varicella rash:

Clinical manifestations: Cont.. Lesions appear first on the scalp, face, or trunk. The initial exanthem consists of intensely pruritic erythematous macules that evolve through the papular stage to form clear, fluid filled vesicles. The distribution of the rash is predominantly central or centripetal, Crops of vesicles ( Vesicles at different stage of development) appear over 3-7 days. Corneal involvement and serious ocular disease are rare.

Clinical manifestations: Cont.. Secondary household andin older children, more lesions usually occur, and new crops of lesions may continue to develop for a longer time. The exanthema may be much more extensive in children with skin disorders Varicella is a more serious disease in young infants, adults, and immunocompromised.

Complication: Staphylococcal and streptococcal superinfection. Otitis media, pneumonia. Transverse myelitis, cerebellar ataxia, encephalitis. bleeding disorders. May disseminate in immunocompromised patients.

Reactivation: Herpes zoster( shingle)

Due to the reactivation of latent VZV. Vesicular rash usually is dermatomal in distribution. Vesicular lesions clustered within 1 or, less commonly, 2 adjacent dermatomes Uncommon in childhood (very rare in healthy children <10 yr of age), milder than disease and is less frequently associated with postherpetic neuralgia. Begins with burning pain followed by clusters of skin lesions in adults

Complication: Infrequently associated with localized pain, Transverse myelitis Transient paralysis is a rare complication. Immunocompromised patients may also experience disseminated cutaneous disease, visceral dissemination with pneumonia, hepatitis, encephalitis, and disseminated intravascular coagulopathy

Diagnosis: Laboratory evaluation has not been considered necessary for the diagnosis or management of healthy children with varicellaor herpes zoster. Diagnosis is mainly clinical The following tests are done in some condition: Direct fluorescence assay (DFA) of cells from cutaneous lesions VZV PCR Tzanck smear: multinucleated giant cells will be seen under microscope. Varecilla serology : IgG and IgM

Treatment of Varicella: Supportive management( fluid, calamine lotion, fever and itching medicine) Acyclovir therapy is not recommended routinely in otherwise healthy child. It is recommended in: Pregnant women Individuals >13 yr of age. Patient with chronic cutaneous or pulmonary disorders. Individuals receiving corticosteroid therapy. Individuals receiving long-term salicylate therapy. Possibly secondary cases among household contacts. Should be initiated as early as possible, preferably within 24 hr of onset of rash.

Herpes Zoster: Treatment of uncomplicated herpes zoster may not always be necessary. Indicated in immunocompromised children. Supportive management ( rest, fluid and pain management ),