herpes zoster and phn (1)
TRANSCRIPT
![Page 1: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/1.jpg)
HERPES ZOSTER & P.H.N
Dr. Ravi Shankar Sharma DARADIA
![Page 2: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/2.jpg)
INTRODUCTION• Viral infection caused by the reactivation of the
varicella-zoster virus (VZV).
• Primary varicella infection - chicken pox.
• Neuronal destruction and inflammation pain interference with daily activities
• Does not cross midline
• Immunocompetent single dermatome affected
Immunocompromisedmultiple dermatomes/ visceral dissemination / cutaneous dissemination
![Page 3: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/3.jpg)
![Page 4: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/4.jpg)
![Page 5: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/5.jpg)
ETIOPATHOGENESIS
•Neurogenicinflammation•Haemorrhagic
necrosis•Neuronal loss
& scarring
Primary VZV infection ( chicken pox )
virus remains dormant in DRG & cranial N nuclei
CMI for VZV decreases with age
VIRAL REPLICATION in DRG
![Page 6: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/6.jpg)
Anti dromic conduction of virus to dermoepidermal junction via cutaneous nerves
•Demyelination•Increase in the electrical
activity of peripheral nociceptors
Inflammation and tissue necrosis leading to rash
PERIPHERAL NERVESSKIN
![Page 7: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/7.jpg)
Pathophysiology PHN
![Page 8: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/8.jpg)
PHASES
• Prodrome
• Rash
• Pain
![Page 9: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/9.jpg)
PRODROME
• Precedes the appearance of rash by 3 – 7 days
• Result of viral replication and inflammation
• Flu like symptoms malaise, fatigue, headache, fever, neck stiffness
• U/L dermatomal pain / altered sensation / pruritis
![Page 10: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/10.jpg)
RASH
Maculopapular rash
7 days
2 –
3 w
eeks
![Page 11: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/11.jpg)
PAIN
• It can precede or accompany the rash
• Burning / throbbing / stabbing / electric shock like pain which may be constant or intermitent
• Associated with hyperaesthesia and allodynia
• Interfere with sleep, physical and emotional functioning
![Page 12: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/12.jpg)
DERMATOMAL DISTRIBUTION
• Thoracic – upto 50%
• Cranial – 10 – 20 %
• Cervical -- 10 – 20 %
• Lumbar – 10 – 20 %
• Sacral – 2 – 8 %
• Generalised - < 1 %
![Page 13: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/13.jpg)
CLINICAL VARIANTS
• Herpes zoster ophthalmicus – ophthalmic division of trigeminal nerve
• Herpes zoster oticus – VII cranial nerve
• Zoster sine herpete – dermatomal pain without rash
![Page 14: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/14.jpg)
LAB DIAGNOSIS• VIRAL CULTURE: (1 to 2 weeks)
• DIRECT IMMUNOFLOUROSCENCE : ( 3 hours)
• VIRAL DNA TESTING(PCR): ( 1 day )
100 %sensitivity in old crusted lesions
• BIOPSY: reserved for difficult to diagnose cases.
- ballooning degeneration
- acantholysis of keratinocytes
- leukoclastocytic vasculitis
![Page 15: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/15.jpg)
DIFFERENTIAL DIAGNOSIS
• Coronary artery disease,
• Pleurodynia
• Costochondritis (Tietze’s syndrome)
• Pericarditis,
• Cholecystitis
• Acute abdominal diseases.
• Disc diseases.
• Nerve diseases and Myofascial pain.
![Page 16: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/16.jpg)
TREATMENT Objectives :
• Reduction of severity and duration of the pain.
• To limit viral replication.
• Recovery of epidermal defects and prevention of secondary infections.
• Reduction or prevention of PHN.
![Page 17: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/17.jpg)
TREATMENT – ACUTE HERPES ZOSTER
CONSERVATIVE MANAGEMENT
• Patient education
- avoid contact with individuals who are seronegative for VZV
- keep rash clean and free of adhesive dressings to prevent secondary infections
![Page 18: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/18.jpg)
ANTI VIRAL THERAPY:
- Inhibit viral DNA polymerase and hence its replication
- must be given to all herpes zoster patients
- beneficial when given within 72 hrs of onset of rash
Those who benefit even > 72 hrs :
- ophthalmic zoster
- immunocompromised
- neurological damage
![Page 19: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/19.jpg)
Benefits of antiviral therapy
• Inhibition of viral replication
• Reduce duration of viral shedding
• Hastens rash healing
• Decrease the degree of neural damage
• Decrease the severity and duration of acute pain
• Decrease duration of PHN
• Decrease incidence of PHN
![Page 20: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/20.jpg)
![Page 21: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/21.jpg)
CONSERVATIVE MANAGEMENT contd
• ANALGESICS:
- mild pain – NSAIDS / acetaminophen / weak opioids
- moderate pain – strong opioids ( effective in reducing pain )
• CO ANALGESICS: gabapentin , pregabalin , TCA’S may be used
![Page 22: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/22.jpg)
CONSERVATIVE MANAGEMENT contd• CORTICOSTEROIDS:
- reduce inflammatory features of acute zoster
- possibly prevent injury to affected neurons
- effective when used in combination with antivirals
- no effect on the healing of rash
- no effect on the occurrence of PHN
![Page 23: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/23.jpg)
INTERVENTIONS
• Single shot epidural with local anaesthetic + STEROID (level B evidence)
• Continuous epidural with LA
• Paravertebral blocks
• Sympathetic blocks
• SCS
![Page 24: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/24.jpg)
![Page 25: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/25.jpg)
PREVENTION
• VZV vaccination for children
• VZIG – for immunocompromised seronegativepatients who are exposed to chicken pox / herpes zoster
• Herpes zoster vaccination for adults
![Page 26: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/26.jpg)
POST HERPETIC NEURALGIA
![Page 27: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/27.jpg)
INTRODUCTION
• POST HERPETIC NEURALGIA : dermatomalpain persistent > 120 days after the onset of rash
• PHN risk factors:
- age > 50 yrs
- painful prodrome
- severe acute pain / rash
![Page 28: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/28.jpg)
PATHOPHYSIOLOGY
VIRAL REPLICATION NEURAL DAMAGE AND
INFLAMMATION (GANGLIONITIS)
SENSITIZATION
PERIPHERAL C FIBRES burning,
hyperalgesia, allodynia
CENTRAL involves NMDA R & Glutamate
R / EPHAPTIC conduction
DEAFFERENTIATION
Loss of large and small diameter fibers
Ectopic discharges
Collateral sproutings
![Page 29: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/29.jpg)
CLINICAL FEATURES• sharp shooting, electric shock like pain
- continuous burning / throbbing pain
• tactile allodynia ( most deblitating )
- hyperalgesia
• Musculoskeletal pain
• Sensory abnormalities :
- hypoaesthesia, altered temperature sensation, paraesthesia, dysaesthesia, chronic pruritis
![Page 30: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/30.jpg)
![Page 31: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/31.jpg)
DIAGNOSIS OF PHN
• h/o rash f/b dermatological pain
• h/o rash 12 months pain free dermatomalpain
• Lab diagnosis :
- quantitative sensory testing
- skin biopsy
- NCV
![Page 32: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/32.jpg)
TREATMENT
OBJECTIVES :
• To alleviate pain
• To Improve quality of life
![Page 33: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/33.jpg)
CONSERVATIVE MANAGEMENT
• ANTICONVULSANTS:
- Gabapentin : alpha 2 delta L type voltage gated Ca++ channel blocker
- start with 300mg / day (max dose upto 3600mg / day )
- Pregabalin : alpha 2 delta L type voltage gated Ca++ channel blocker
- start with 150 mg / day ( max upto 600 mg/day)
- better tolerated
![Page 34: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/34.jpg)
CONSERVATIVE MANAGEMENT contd
• ANTI DEPRESSANTS:
- TCA’s : amitryptyline / nortryptyline
• Provides moderate to excellent pain relief .
(used esp in those suffering with insomnia)
desipramine – less sedating
- SNRI’s : not FDA approved
duloxetine is still used
![Page 35: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/35.jpg)
CONSERVATIVE MANAGEMENT contd
• OPIOIDS: Tramadol & Oxycodone useful
CLINICAL RECOMMENDATIONS:• Use lowest effective dose• Initiate with short acting opioids
• Convert to long acting • Proactively combat nausea and constipation
![Page 36: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/36.jpg)
![Page 37: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/37.jpg)
INTERVENTIONAL MANAGEMENT• SYMPATHETIC NERVE BLOCKS :
- Good evidence- it reduces sympathetically mediated neuronalinflammation
• SPINAL CORD STIMULATION : good evidence
• POOR EVIDENCE :- Continuous epidural for one week- intercostal N block- transforaminal DRG- intra thecal opioids
• PRF leisoning• Narrow band UVB
![Page 38: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/38.jpg)
PREVENTION OF PHN
• Vaccination
• Anti viral therapy
• Pharmacotherapy – alleviate pain
• Sympathetic blocks
![Page 39: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/39.jpg)
PREVENTION OF PHN
• Vaccination
• Early antiviral therapy
• Early treatment of neuropathic pain
![Page 40: Herpes zoster and phn (1)](https://reader034.vdocuments.site/reader034/viewer/2022051404/5a66691b7f8b9a47688b60b5/html5/thumbnails/40.jpg)
Thank YOU