Summary about Disease
Varicella Zoster Ophthalmicus (VZO) is a reactivation of the varicella-zoster virus (VZV), the same virus that causes chickenpox. After a person has chickenpox, the virus lies dormant in nerve cells. VZO occurs when the virus reactivates in the ophthalmic branch of the trigeminal nerve, which supplies sensation to the forehead, upper eyelid, and nose, and can affect the eye itself. It's characterized by a painful, blistering rash along the distribution of this nerve and can lead to serious complications affecting vision.
Symptoms
A tingling, burning, or itching sensation on the forehead, scalp, or around the eye, preceding the rash by days or weeks.
Headache, fever, and malaise.
A red, blistering rash that appears on the forehead, scalp, and potentially the nose and around the eye. The rash typically stops at the midline of the forehead.
Eye symptoms such as redness, pain, swelling, blurred vision, sensitivity to light (photophobia), and tearing.
Possible involvement of the eye itself, leading to conditions like conjunctivitis, keratitis (inflammation of the cornea), uveitis (inflammation inside the eye), and optic neuritis (inflammation of the optic nerve).
Causes
VZO is caused by the reactivation of the varicella-zoster virus (VZV). The virus remains dormant in the dorsal root ganglia after a person has had chickenpox. Reactivation can occur due to factors like:
Weakened immune system (due to age, illness, medications like immunosuppressants).
Stress.
Physical trauma.
Medicine Used
4. Medicine used
Antiviral medications: These are the mainstay of treatment and are most effective when started within 72 hours of rash onset. Common antivirals include:
Acyclovir
Valacyclovir
Famciclovir
Pain relief medications:
Over-the-counter pain relievers (e.g., acetaminophen, ibuprofen) for mild pain.
Prescription pain medications (e.g., opioids) for severe pain.
Topical agents such as capsaicin cream (after the rash has healed) for postherpetic neuralgia.
Corticosteroids: May be used in some cases to reduce inflammation, but their use is controversial.
Eye drops:
Artificial tears for dryness.
Steroid eye drops to reduce inflammation in the eye.
Antibiotic eye drops if there's a secondary bacterial infection.
Pupil dilating eye drops to help with pain from uveitis.
Is Communicable
VZO itself is not directly communicable in the sense that someone with VZO cannot give another person VZO. However, a person with VZO can transmit the varicella-zoster virus to someone who has never had chickenpox or the chickenpox vaccine. In this case, the person exposed to the virus would develop chickenpox, not shingles. The risk of transmission is highest when the rash is in the blister phase. Once the blisters have crusted over, the risk decreases significantly.
Precautions
Avoid contact: Keep the rash covered to prevent contact with others, especially pregnant women who have never had chickenpox or the chickenpox vaccine, infants, and people with weakened immune systems.
Handwashing: Wash hands frequently and thoroughly to prevent the spread of the virus.
Avoid sharing: Do not share towels, clothing, or other personal items with others.
Vaccination: Shingrix (recombinant zoster vaccine) is recommended for adults 50 years and older to prevent shingles and postherpetic neuralgia, even if they have had shingles before.
Hygiene: Keep the affected area clean and dry to prevent secondary bacterial infections.
How long does an outbreak last?
An outbreak of VZO typically lasts for 3 to 5 weeks. The timeline can vary from person to person.
How is it diagnosed?
Diagnosis is typically based on:
Clinical presentation: The characteristic rash along the distribution of the ophthalmic branch of the trigeminal nerve is usually diagnostic.
Patient history: A history of chickenpox is suggestive.
Eye exam: A thorough eye exam is essential to assess for ocular involvement.
Laboratory tests: In some cases, laboratory tests may be performed to confirm the diagnosis, such as:
Viral culture of fluid from the blisters.
Polymerase chain reaction (PCR) testing of blister fluid or swabs to detect VZV DNA.
Direct fluorescent antibody (DFA) testing of skin scrapings.
Timeline of Symptoms
9. Timeline of symptoms
Prodromal phase (1-7 days before rash): Tingling, burning, itching, headache, fever, malaise.
Acute phase (rash onset): Redness, blisters appear, pain intensifies. This phase lasts for 2-4 weeks.
Postherpetic Neuralgia (PHN): Chronic pain that can persist for months or years after the rash has healed. PHN is not always present.
Important Considerations
Ocular involvement is serious: Prompt ophthalmological evaluation is crucial to prevent vision loss.
Early treatment is key: Antiviral medications are most effective when started within 72 hours of rash onset.
Postherpetic neuralgia (PHN): PHN is a common complication and can be debilitating. Management may involve pain medications, nerve blocks, and topical treatments.
Vaccination: Vaccination with Shingrix can significantly reduce the risk of developing shingles and PHN.
Immunocompromised individuals: Individuals with weakened immune systems are at higher risk for severe complications and should be monitored closely.