Symptoms
After the initial clinical manifestation in the form of chickenpox, the virus remains in a latent stage in the dorsal root ganglia for life. Reactivation of the virus occurs particularly in the presence of weakened immune defenses. Vesicles with cloudy contents form in the area supplied by the infected nerve, e.g. on the trunk or face, and crust over as the disease progresses. The vesicles are infectious as long as they are not crusted and can cause chickenpox in children. They regress after 2-3 weeks. After healing, severe nerve pain may occur (called postherpetic neuralgia, postzoster neuralgia). The pain can last for months to years. Immunosuppressed and elderly persons represent the main patient group. However, shingles is also observed in young and healthy individuals (!)
Causes
Endogenous reactivation of varicella zoster virus (human herpesvirus 3, a DNA virus of the herpesvirus family), which causes chickenpox in childhood.
Transmission
Droplet or smear infection, such as contact with vesicle contents containing the virus. Patients with shingles can infect children with chickenpox.
Complications
Complications increase with age, and neurologic complications are particularly common:
- Paralysis of the face
- Meningoencephalitis
- Inflammation of the bone marrow
- Guillain-Barré syndrome (inflammation of the spinal nerve roots and peripheral nerves).
- Postherpetic neuralgia (pain of the nerves that persists even after the skin reaction has healed).
- If the trigeminal nerve is involved: zoster ophthalmicus (can cause blindness and facial paralysis) or zoster oticus (can cause hearing and balance disorders and facial paralysis)
- In immunocompromised individuals: generalized infection leading to death in 40% of cases.
- Other complications: severe pain, scarring, pneumonia, hepatitis.
Risk factors
- Age over 50 years
- Weakened immune system
- HIV infection
Risk factors for the development of postherpetic neuralgia:
- Age over 50 years
- Severe pain when the skin lesions appear
- Occurrence of prodromal symptoms
Diagnosis
Diagnosis is made by the physician on the basis of the clinical picture of the disease or by antibody detection.
Differential diagnosis
- Other viral skin infections such as herpes simplex, coxsackie virus.
- Erysipelas
- Impetigo
- Eczema herpeticum
Drug treatment
Antiviralia / nucleoside analogues are directly effective against the viruses. Antiviral therapy causes faster regression and healing of the rash, as well as pain relief. It is the most efficient treatment if initiated within 72 h of the onset of symptoms. The effect of early therapy with antiviralia on the course and prevention of postherpetic neuralgia is controversial.
Substances against neuropathic pain:
- NSAIDs and acetaminophen are often ineffective but may provide relief for some patients.
- Topical therapy: capsaicin cream, local anesthetics, e.g., lidocaine.
- Opioids: fentanyl
- Antidepressants: amitriptyline
- Tramadol or tapentadol
- Antiepileptic drugs: Pregabalin, gabapentin, carbamazepine.
Because shingles particularly affects the elderly, it should be noted that carbamazepine can cause dizziness as an adverse effect, increasing the risk of serious falls.
- White shaking mixture
Tannins are astringent, anti-inflammatory and antimicrobial:
- E.g. Tannosynt
Disinfectant:
Prevention
- Vaccines are available.
- Postexposure prophylaxis with varicella-zoster immunoglobulin.