In Herpes-Zoster keratitis, all of the following occurs except:
Ans. c. Sclerokeratitis (Ref: Kansk is 7/ep 187-91; Yanoff 3/ep. 222-24)Herpes Zoster ophthalmicus commonly causes acute epithelial keratitis [i.e. punctuate epithelial keratitis (in 50%) and pseudo dendritic keratitis (50%)}, nummular (anterior stromal) keratitis (40%) disciform (deep stromal) keratitis or endothelitis (34%) and serpiginous ulceration (7%). However, sclera-keratitis (limbal vascular keratitis) is least common ( !%).Herpes Zooster Opthalmicus (HZO)* It is caused by varicella zoster virus0 (DNA virus)* After an infection with chicken pox in childhood or youth the virus lies dormant in Gasserian ganglion of trigeminal nerve to appear later, particularly in elderly people with depressed cellular immunity e.g. cancer, leukaemia, AIDS, lymphoma and immunosuppressed organ transplant recipients etc.Herpes Zooster Opthatmicus (HZO)Clinical features* Hutchinson sign: In herpes zoster opthalmicus. Involvement of the tip of nose supplied by external nasal nerve (a terminal branch of nasociliary nerve), signifies increase risk of ocular involvement (uveitis).* Lesions are strictly limited to the one side of midline.* Bilateral lesions can occur in the immunocompromisedClinical PresentationGeneral featuresCutaneous lesionsOcular lesionsNeurological complications* Onset of illness is sudden with fever, malaise* Severe neuralgic pain along the course of the affected nerve* Appear in the area of involved nerve after 3-4 days of onset of disease.* Affected areas becomes red and edematous followed by vesicle formation.* Can cause small permanent pitted scars.* Active eruptive stage lasts for 3 weeks.* Anaesthesia dolorosa: Anaesthesia of the affected skin with associated post herpetic neuralgia* Conjunctivitis: One of the MC complication* Episcleritis and scleritis* Keratitis:- Punctate epithelial keratitis0(fine or coarse)- Microdendritic epithelial ulcers- Nummular keratitis0- Disciform keratitis- Neuroparalytic ulcerations- Exposure keratitis* Iridocyclitis0* Secondary glucoma0* Anterior segment necrosis and pthisis bulbi* Motor nerve palsies especially 3rd, 4th, 6th and 7th* Optic neuritis* EncephalitisTreatment:* Oral acyclovir (no later than 4 days after the onset of rash)* In scleritis, sclerosing keratitis or iritis, dexamethasone 0.1% along with antiviral is used topically* Systemic steroids are used in progressive proptosis with total occulomotor nerve palsy and optic neuritis.* Oxyphenbutazone (NSAIDs) are sometimes useful in severe scleritis not responding to steroids.
Pseudodendritic keratitis
Anterior stromal invasion
Sclerokeratitis
Endotheelitis
Inflammations of the Cornea