Author:
            AaronHexdall
            MyungBae
            
Description
- Viral disease characterized by recurrent painful vesicular lesions of mucocutaneous areas
- Lips, genitalia, rectum, hand s, and  eyes most commonly involved
- Infection is characterized by 2 phases:- Primary, virus established in a nerve ganglion
- Secondary, recurrence of disease at the same site
 
- Incubation period is ∼4 d from exposure
- Viral shedding occurs from 7-10 d (up to 23 d) in primary infection and  3-4 d in recurrent infections
- Neonatal infections can occur in utero, intrapartum (most common), or postnatal- Occur in 1/3,500 births per year in the U.S.
 
- Human-to-human transmission
- HSV-1 - one of the most common viral causes of encephalitis in the U.S.- Untreated infection with mortality rate >70%
 
- HSV-1 usually from childhood through nonsexual contact
- HSV-2 almost always sexually transmitted
- 60-90% of population is infected with herpes simplex type 1 (HSV-1) or type 2 (HSV-2)
- More common in blacks than whites in ages <40 yr
- Females affected more than males
Etiology
- HSV-1 or HSV-2 are DNA viruses of the Herpesviridae family
- Viral transmission may occur via respiratory droplets, contact with mucosa or abraded skin with infected secretions: saliva, vesicle fluid, semen, cervical fluid:- Recurrent mucosal shedding of HSV may transmit the virus
- Rate of recurrence varies with virus type and  anatomic site
 
- Both viruses infect oral or genital mucosa:- Most common for HSV-1 to cause oral infections and  HSV-2 to cause genital infections
 
- Herpes Simplex Encephalitis: Access via olfactory or the trigeminal nerve:- Prefers medial and  inferior temporal lobes
 
Signs and  Symptoms
- Many primary infections go unrecognized and  can only be detected by an elevated IgG Ab titer
- Clinically, infection presents with grouped 1-2-mm vesicles on an erythematous base
- Vesicles may be filled with clear or cloudy fluid or may appear as frank pustules
Orofacial infection:
- Primary infection:- Gingivostomatitis or pharyngitis:- Ulcerative exanthem involving gingival and  mucous membranes
- Fever, malaise, irritability, headache, myalgias, cervical adenopathy
- Primary infection symptoms typically last 2-4 wk unless secondarily infected and  heal without scarring
- Inability to eat owing to pain is a risk for dehydration
 
 
- Recurrent infection (recrudescence):- Usually involves lips, specifically the vermillion border (herpes labialis)
- Commonly incited by sunlight, heat, stress, trauma (chapping, abrasions), or immunosuppression
- Prodrome of itching, tingling, throbbing, or burning followed by erythema, papule/vesicle, ulcer, crust, and  healing
- Transmission can occur in the absence of recognizable lesions
- Fewer constitutional symptoms
- Many individuals have a rise in Ab titer and  never experience recurrence
- HSV-1 oral infections recur more often than genital HSV-1 infections
- HSV-2 genital infections recur 6 times more frequently than HSV-1 genital infections
 
Skin infection:
- History of exposure to HSV-1 or HSV-2
- Abrupt onset of fever, edema, erythema, and  localized tenderness
- Herpetic whitlow:- HSV-2 more common than HSV-1
- Infection of pulp and  lateral aspect of finger with single or multiple vesicles
- May occur from autoinoculation with primary oral or genital infection or from direct inoculation from occupational exposure
- Can last 3-4 wk
- Recurrence possible
- In young children, it is associated with HSV-1 inoculation through thumb sucking during gingivostomatitis
 
- Traumatic herpes:- Can occur following cosmetic procedures of face, surgical and  dental interventions, sun exposure, or burns
 
- Herpes gladiatorum:- Mucocutaneous infection of athletes involving chest, face, and  hand s transmitted through traumatized skin (often wrestlers)
 
- Eczema herpeticum:- Association between atopic dermatitis and  HSV infection
- HSV-1 more common than HSV-2
- Occurs in children and  young adults with atopic dermatitis
- Secondary staphylococcal infection commonly occurs
- Higher risk if on steroids or infected with HIV
- Varicelliform eruption with spread to surrounding skin
- Fever, headache, and  fatigue
 
- HSV-associated erythema multiforme:- Usually presents on palms and  soles
- Lasts 2-3 wk
 
Eye:
- Most common cause of corneal blindness
- Caused by extension of facial lesions or direct inoculation
- Acute onset of pain and  photophobia
- Periauricular adenopathy, blurry vision, chemosis, and  conjunctivitis
- May be unilateral or bilateral
- Dendritic lesions of cornea noted on fluorescein exam
- Different from herpes varicella zoster as dermatome not involved
- Hutchinson sign:- Vesicles on tip of nose may indicate ocular disease
- Involvement of nasociliary nerve
 
CNS/encephalitis:
- Most common cause of severe sporadic encephalitis in the western world
- Usually from HSV-1 reactivation disease
- Hallmark symptoms: acute onset of fever and  neurologic symptoms:
- Meningitis in females with HSV 2 infection:- Benign course compared to encephalitis
- Some may develop recurrent lymphocytic meningitis (Mollaret syndrome)
 
History
May or may not have known history of exposure to HSV-1 or HSV-2
Physical Exam
Vesiculoulcerative lesions in orofacial or genital area
| Pediatric Considerations | 
| Up to 60-80% of babies who develop neonatal HSV are born to mothers without history of genital herpesVesicular skin lesions may or may not be present on initial examPrimary genital disease of the mother increases risk of transmitting virus to fetusMost primary infections occur during childhood; symptomatic in only 5-10% of childrenOrofacial disease is most likely to present as gingivostomatitis in children younger than 5 yr of ageWhitlow may be caused by thumb-sucking children with oral herpes
 | 
 
Essential Workup
- Herpes encephalitis:- Lumbar puncture if herpes encephalitis is considered
 
- Herpes ophthalmicus:- Fluorescein exam if ocular herpes is a concern
 
Diagnostic Tests & Interpretation
- Orofacial:- Presumptive diagnosis made by history and  exam
- If definitive diagnosis is necessary (e.g., systemic disease, child abuse):- Viral culture or polymerase chain reaction (PCR) testing of swabs from vesicles
- Collection from unroofed vesicles is preferred
 
- PCR is the most accurate and  reliable method for detecting the virus:- Fluorescent antibody detection of antigen; serum antibody studies
- Scrapings for Tzanck smear or Papanicolaou stain
- Skin biopsy if hyperkeratotic or lichenoid lesions
 
 
- Eye:- Dendritic corneal lesions by fluorescein exam
- Swab of affected area for viral culture or fluorescent antibody detection
 
- CNS/encephalitis:- Lumbar puncture with CSF pleocytosis and  negative bacterial antigens
- CSF PCR - testing modality of choice
- MRI/CT (abnormalities in temporal lobe may be visualized)
- EEG diagnostic if spike and  waves in temporal region - (typical intermittent, high-amplitude slow waves localized to the temporal lobe)
 
Lab
- Lesion scrapings can be sent for culture or PCR testing
- Tzanck smear demonstrating multinucleated giant cells, atypical keratinocytes, and  large nuclei
- Serum testing has limited ED use
- ELISA testing may demonstrate HSV antibodies, determining past exposure only
- Requires 2 wk to >3 mo to detect seroconversion
Differential Diagnosis
- Orofacial and  skin:- Bacterial pharyngitis
- Mycoplasma pneumoniae pharyngitis
- Stevens-Johnson syndrome
- Herpes zoster
- Varicella
- Pemphigus
- Contact or chemical dermatitis
- Impetigo
- Syphilis
 
- Eye:- Conjunctivitis: Viral, bacterial, or allergic
- Herpes zoster ophthalmicus
- Scleritis/episcleritis
- Angle-closure glaucoma
- Corneal abrasion
 
- Neuro:- Acute disseminated encephalomyelitis
- HIV encephalitis
- Complex partial seizure
- Subarachnoid hemorrhage
- Bacterial meningitis
- Migraine
- Neurosyphilis
- Paraneoplastic encephalitis
- Epilepsy
 
Prehospital
- Maintain universal precautions
- Pain control
Initial Stabilization/Therapy
Protect airway in comatose or obtunded patients with suspected CNS disease
ED Treatment/Procedures
- Orofacial/gingivostomatitis:- Primary disease in healthy children is generally not treated
- Primary disease in normal host with mild disease requires only supportive treatment with hydration and  analgesia
- Severe disease or immunocompromised patients: IV or oral acyclovir, valacyclovir, or famciclovir
- Oral acyclovir is first-line medication
- Valacyclovir, famciclovir: similar efficacy, but require fewer doses per day
- If recurrent disease, oral antivirals are most helpful if started with prodrome or at first sign of lesion:- Reduces lesions and  symptoms by 1-2 d
 
- Consider prophylaxis in patients with more than 6 episodes per year; history of herpes-associated erythema multiforme or herpes gladiatorum; upcoming intense sun exposure or stress; perioral/intraoral surgery; cosmetic facial procedures:- Prophylaxis reduces frequency and  severity of herpes labialis and  may help decrease asymptomatic shedding, leading to decreased transmission
- Does not cure or terminate the disease
- When prophylaxis is stopped, most patients have recurrences
 
 
- Skin (other than orofacial or genital):- May be treated with oral acyclovir
- Antibiotics if secondary bacterial infection
- Do not incise and  drain: May lead to spread of infection
 
- Eye:- Oral acyclovir and  topical antiviral therapy with trifluridine or vidarabine
- Vidarabine ointment for children
- Do not treat with steroids: May cause increased viral replication
- Ophthalmology consult
 
| Pregnancy Prophylaxis | 
| 60% of pregnant women are seropositive for HSV-120% of pregnant women are seropositive for HSV-2Maternal primary infection at time of delivery leads to 60% risk of neonatal herpesIf history of genital herpes, initiate antiviral therapy from 36 wk until deliveryElective cesarean if active lesions
 | 
 
Medication
- Acyclovir:- Orofacial and  skin: 400 mg PO t.i.d for 7-10 d or 5-10 mg/kg IV q8h for 7-14 d
- Pediatric mucocutaneous primary infection: 40-80 mg/kg PO in 3-4 div doses for 5-10 d; max dose 1 g/d
- Eyes for suppression therapy: 400 mg PO b.i.d
- Encephalitis: 30 mg/kg/24 h IV div q8h for 14-21 d
 
- Famciclovir:- Primary orofacial: 250 mg PO t.i.d for 7-10 d (immunocompetent), 500 mg PO b.i.d for 7-10 d (immunocompromised)
 
- Trifluridine:- Adults and  peds older than 6 yr: 1 drop of 1% ophthalmic ointment to eye q2h while awake (max 9 drops per day) until ulcer re-epithelialized
- Additional 7 d of one drop q4h while awake for a min daily dosage of 5 drops recommended
- Consult ophthalmology if no improvement after 7 d of therapy or re-epithelialization does not occur for 14 d
 
- Valacyclovir:- Adults primary mucocutaneous: 1,000 mg PO b.i.d for 7 d
- Adult recurrent mucocutaneous (nongenital): 500 mg PO b.i.d for 3 d
 
- Vidarabine:- Adults or peds older than 2 yr: Topical 0.5 in ribbon of 3% ophthalmic ointment to eye 5 times per day at 3-h intervals
 
- Recurrent mucocutaneous herpes:- Acyclovir: 400 mg PO t.i.d for 5 d
- Famciclovir: 1,000 mg PO b.i.d for 1 d
- Valacyclovir: 500 mg PO b.i.d for 3 d
 
- Long-term prophylaxis:- Acyclovir: 400 mg PO b.i.d
- Valacyclovir: 500 mg PO daily
- Famciclovir: 250 mg PO b.i.d
 
| ALERT | 
| Antiviral dosing may need adjustment for renal failureTopical antivirals are available but have not been shown to reduce the length of symptoms or decrease recurrence
 | 
 
Disposition
Admission Criteria
- Encephalitis, disseminated disease, dehydration
- Severe local or disseminated disease in immunocompromised host
- Neonatal HSV
- ICU vs. ward based on toxicity and  need for airway support
- Ophthalmology consult vs. admission for ocular involvement
Discharge Criteria
Uncomplicated local disease
Issues for Referral
- Suppressive treatment options
- Herpes infection during pregnancy
Follow-up Recommendations
Skin/genital infection:
- Follow-up with the patient's primary doctor to discuss risks and  benefits of suppressive therapy
- CernikC, GallinaK, BrodellRT. The treatment of herpes simplex infections: An evidence based review . Arch Intern Med. 2008;168:1137-1144.
- GrovesMJ. Genital herpes: A review . Am Fam Physician. 2016;93:928-934.
- MellHK. Management of oral and  genital herpes in the emergency department . Emerg Med Clin North Am. 2008;26:457-473.
- Sand ersJE, GarciaSE. Pediatric herpes simplex virus infection: An evidence-based approach to treatment . Pediatric Emergency Medicine Practice. http://www.ebmedicine.net/topics.php?paction=showTopic&topic_id=390. Published January 2014.
- WHO Guidelines for the Treatment of Genital Herpes Simplex Virus. Geneva: World Health Organization; 2016.
See Also (Topic, Algorithm, Electronic Media Element)