User Tools

Site Tools


herpes_zoster

Herpes zoster

Shingles, also known as herpes zoster, is a viral disease characterized by a painful skin rash with blisters in a localized area.

Typically the rash occurs in a single, wide stripe either on the left or right of the body or face.

Two to four days before the rash occurs there may be tingling or local pain in the area.

Otherwise there are typically few symptoms.

The rash usually heals within two to four weeks; however, some people develop ongoing nerve pain which can last for months or years, a condition called postherpetic neuralgia.

In those with poor immune function the rash may occur widely.

If the rash involves the eye, vision loss may occur.

Shingles is due to a reactivation of varicella zoster virus (VZV) within a person's body.

The disease chickenpox is caused by the initial infection with VZV.

Once chickenpox has resolved, the virus may remain inactive in nerve cells.

When it reactivates, it travels from the nerve body to the endings in the skin, producing blisters.

Risk factors for reactivation include old age, poor immune function, and having had chickenpox before 18 months of age.

How the virus remains in the body or subsequently re-activates is not well understood.

Exposure to the virus in the blisters can cause chickenpox in someone who has not had it before, but will not trigger shingles.

Diagnosis is typically based on a person's signs and symptoms.

Varicella zoster virus is not the same as herpes simplex virus; however, they belong to the same family of viruses.

Results suggest that psoriasis is associated with an increased risk of herpes zoster (HZ), which involves differences in sex and age. Although systemic therapy may have a major role in the risk of HZ, the intrinsic factors of psoriasis cannot be excluded 1).

see Ramsay Hunt syndrome.

Treatment

Oral antiherpetic drugs: Also effective (they shorten the duration of pain), and also reduce the incidence of PHN. They may cause thrombotic thrombocytopenic purpura/hemolytic uremic syndro- me (TTP/HUS) when used in severely immunocompromised patients at high doses. These drugs include:

Acyclovir (Zovirax®): poorly absorbed from the GI tract (15–30% bioavailability). ℞ 800 mg PO q 4 hrs 5 times/d × 7 d.

Valacyclovir (Valtrex®)33 is a prodrug of acyclovir and is more completely absorbed and should be equally as effective with fewer daily doses. ℞ 1,000 mg PO TID starting within 72 hrs of onset of the rash × 7 days. Famciclovir (Famvir®): ℞ 500 mg PO TID × 7 d.

1)
Tsai SY, Chen HJ, Lio CF, Ho HP, Kuo CF, Jia X, Chen C, Chen YT, Chou YT, Yang TY, Sun FJ, Shi L. Increased risk of herpes zoster in patients with psoriasis: A population-based retrospective cohort study. PLoS One. 2017 Aug 22;12(8):e0179447. doi: 10.1371/journal.pone.0179447. eCollection 2017. PubMed PMID: 28829784.
herpes_zoster.txt · Last modified: 2019/10/28 16:26 by administrador