A PAINFUL, VESICULAR inflammation of the tip of the finger or toe, herpetic whitlow is caused by herpes simplex virus (HSV) type 1 or 2. The condition develops when oral secretions or mucous membranes infected with HSV come in contact with a cutaneous break, such as an abrasion or torn cuticle. Health care workers, especially nurses and respiratory and anesthesiology staff, are particularly susceptible because of their hands-on contact with patients who may be infected.
How infection develops
After an incubation period of 2 to 14 days, the patient may experience prodromal symptoms, such as fever and malaise. Common initial symptoms of infection include tingling pain or tenderness in the affected digit, followed by throbbing pain, swelling, and redness. Vesicles, which form over the next week, contain fluid that may be clear, bloody, or cloudy. While these vesicles are present, herpetic whitlow is extremely contagious.
About 2 weeks after vesicles first appear, a crust forms over them. This signals the end of viral shedding.
If untreated, the infection usually resolves in 3 to 4 weeks. Treatment with antiviral medication may speed healing and reduce viral shedding, but some patients never regain full sensitivity or range of motion in the digit.
Herpetic whitlow vesicles are susceptible to secondary bacterial infections. Signs and symptoms of a secondary infection include fever, chills, red streaks the length of the arm, lymphadenopathy, and fatigue.
After healing, from 20s% to 50% of patients experience recurrences, which may be triggered by trauma, febrile illness, disease, or other physiologic changes. The recurrence usually is milder and clears up faster than the original infection.
The health care provider will base her diagnosis on signs and symptoms and confirm it with lab testing. Options include isolating the virus from a sample of vesicular fluid, a Tzanck test (a stain histology test), and serum immunoglobulin antibody testing for HSV IgM (to detect acute HSV) and IgG (to detect a history of HSV).
Healing and prevention
To treat herpetic whitlow, the health care provider will order an oral, topical, or I.V. antiviral medication, such as acyclovir, famciclovir, or valacyclovir. These medications accelerate healing, reduce viral shedding and pain, and may help prevent a recurrence. She'll also prescribe treatment for secondary infection, if indicated. Incision and drainage of vesicles isn't indicated because this may spread the infection.
For comfort, lesions should be bandaged (but not tightly). Teach the patient to change soiled or damp bandages promptly.
To protect yourself from infection, follow standard precautions. Wear gloves and take other standard contact precautions whenever you may have contact with a patient's body fluids, blisters, lesions, or mucous membranes or with any item that's touched a patient's mucous membranes or body fluids.
Practice good hand hygiene when you remove your gloves. If you're using an alcohol-based hand rub, remember that the antiseptic must remain in contact with all skin surfaces for 15 seconds to kill viruses and other pathogens—a quick rub isn't good enough. Keep your skin moisturized to prevent cracked skin, which provides an opening for pathogens.
If you develop herpetic whitlow, follow your facility's policy and procedure to prevent disease transmission. The Centers for Disease Control and Prevention recommends restricting health care providers from contact with patients or patient environments until lesions heal.
Barbara Wyand Walker is an infection control/employee health nurse at Greenbrier Valley Medical Center in Ronceverte, W.Va.
SELECTED WEB SITES
American Social Health Association http://www.ashastd.org
eMedicine, herpetic whitlow http://www.emedicine.com/emerg/topic754.htm
Centers for Disease Control and Prevention http://www.cdc.gov
Last accessed on June 2, 2004.
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