Overview

Herpetic whitlow is a painful viral infection that affects the fingers or, less commonly, the toes. It is caused by the herpes simplex virus (HSV), which is the same virus responsible for cold sores and genital herpes. Herpetic whitlow leads to the formation of painful blisters or sores on the affected digit, accompanied by redness, swelling, and tenderness. While it is not a life-threatening condition, it can cause significant discomfort and may recur in some individuals. Prompt diagnosis and appropriate care can help reduce symptoms and prevent transmission to others.

Causes

The primary cause of herpetic whitlow is infection with the herpes simplex virus (HSV). There are two types of HSV that can cause this condition:

• HSV-1: Commonly associated with oral herpes (cold sores) and is often transmitted through contact with infected saliva.
• HSV-2: Usually linked to genital herpes and transmitted through contact with infected genital secretions.

Herpetic whitlow typically occurs when broken skin on the fingers or hands comes into direct contact with the virus. It is especially common in healthcare workers, dental professionals, or individuals who have frequent contact with oral or genital secretions. It can also happen in children who suck their thumbs or bite their nails, transferring the virus from the mouth to the fingers.

Symptoms

Symptoms of herpetic whitlow usually appear within 2 to 20 days after exposure to the herpes virus. The main signs and symptoms include:

• Painful swelling: The affected finger or toe becomes swollen, red, and extremely tender to touch.
• Blisters: Groups of small, clear, fluid-filled blisters appear, often surrounded by red skin.
• Burning or tingling: Some people experience a burning or tingling sensation before blisters develop.
• Ulceration: Blisters may rupture, forming small open sores or ulcers that later crust over and heal.
• Fever and swollen lymph nodes: Some individuals may have mild fever and tender lymph nodes near the affected area.
• Recurrence: Like other herpes infections, herpetic whitlow can recur periodically, although episodes are often milder after the first infection.

Diagnosis

Diagnosing herpetic whitlow involves a combination of clinical examination and laboratory tests:

• Clinical examination: A healthcare provider will inspect the affected finger for characteristic blisters and symptoms.
• Patient history: Information about recent exposure to individuals with cold sores or genital herpes can aid diagnosis.
• Viral culture: A sample of fluid from the blister can be tested in a laboratory to confirm the presence of the herpes simplex virus.
• PCR testing: Polymerase chain reaction (PCR) tests can detect HSV DNA and are highly sensitive and accurate.
• Tzanck smear: A microscopic examination of cells from the blister, although less commonly used today.

Treatment

There is no cure for herpetic whitlow, but treatment focuses on relieving symptoms, shortening the duration of outbreaks, and preventing complications:

• Antiviral medications: Oral antivirals such as acyclovir, valacyclovir, or famciclovir can reduce the severity and duration of symptoms, especially when started early.
• Pain management: Over-the-counter pain relievers like acetaminophen or ibuprofen help reduce pain and swelling.
• Wound care: Keep the area clean, dry, and avoid rupturing the blisters to prevent secondary bacterial infections.
• Topical treatments: In some cases, topical antiviral creams may be recommended, although oral antivirals are more effective.
• Avoiding transmission: Cover the affected area, avoid close contact, and practice good hand hygiene to prevent spreading the virus to others or to other body parts.

Prognosis

The prognosis for herpetic whitlow is generally good. Symptoms typically resolve within 2 to 3 weeks without complications. While the first episode is usually the most painful and severe, recurrent episodes may be milder and less frequent.

Some individuals may experience occasional flare-ups triggered by factors such as stress, illness, or injury to the affected area. With proper care and the use of antiviral medications during outbreaks, most people with herpetic whitlow can manage the condition effectively and lead normal lives.

Early treatment reduces the risk of prolonged symptoms and minimizes the chance of spreading the virus to others.