A herpetic whitlow is a

lesion A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals. Types There is no designated classif ...

( whitlow), typically on a finger or thumb, caused by the

herpes simplex virus Herpes simplex virus 1 and 2 (HSV-1 and HSV-2), also known by their taxonomical names '' Human alphaherpesvirus 1'' and ''Human alphaherpesvirus 2'', are two members of the human ''Herpesviridae'' family, a set of viruses that produce viral in ...

(HSV). Occasionally infection occurs on the toes or on the nail cuticle. Herpes whitlow can be caused by infection by HSV-1 or HSV-2. HSV-1 whitlow is often contracted by health care workers that come in contact with the virus; it is most commonly contracted by dental workers and medical workers exposed to oral secretions. It is also often observed in

thumb-sucking Thumb sucking is a behavior found in humans, chimpanzees, captive ring-tailed lemurs, and other primates.Benjamin, Lorna S.: "The Beginning of Thumbsucking." ''Child Development'', Vol. 38, No. 4 (Dec., 1967), pp. 1065–1078. It usually involve ...

children with primary HSV-1 oral infection (

autoinoculation Autoinoculation is derived from the Latin root words "autos" and "inoculate" that mean "self implanting" or "self infection" or "implanting something from oneself". Autoinoculation can refer to both beneficial medical procedures (e.g. vaccination) a ...

) prior to

seroconversion In immunology, seroconversion is the development of specific antibodies in the blood serum as a result of infection or immunization, including vaccination. During infection or immunization, antigens enter the blood, and the immune system begins t ...

, and in adults aged 20 to 30 following contact with HSV-2-infected genitals.

Symptoms and signs

Symptoms of herpetic whitlow include swelling, reddening, and tenderness of the infected part. This may be accompanied by fever and swollen lymph nodes. Small, clear vesicles initially form individually, then merge and become cloudy, unlike in bacterial whitlow when there is pus. Associated pain often seems largely relative to the physical symptoms. The herpes whitlow lesion usually heals in two to three weeks. It may reside in axillary sensory ganglia to cause recurrent herpetic lesions on that arm or digits. Blistering can occur in severe cases.

Causes

In children the primary source of infection is the orofacial area, and it is commonly inferred that the

virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsk ...

(in this case commonly HSV-1) is transferred by the cutting, chewing or sucking of fingernail or thumbnail. In adults, it is more common for the primary source to be the

genital A sex organ (or reproductive organ) is any part of an animal or plant that is involved in sexual reproduction. The reproductive organs together constitute the reproductive system. In animals, the testis in the male, and the ovary in the female, a ...

region, with a corresponding preponderance of HSV-2. It is also seen in adult health care workers such as

dentist A dentist, also known as a dental surgeon, is a health care professional who specializes in dentistry (the diagnosis, prevention, management, and treatment of diseases and conditions of the oral cavity and other aspects of the craniofacial c ...

s because of increased exposure to the herpes virus. Contact sports are also a potential source of infection with herpetic whitlows.

Treatment

Although it is a self-limited illness, oral or intravenous

antiviral Antiviral drugs are a class of medication used for treating viral infections. Most antivirals target specific viruses, while a broad-spectrum antiviral is effective against a wide range of viruses. Unlike most antibiotics, antiviral drugs do n ...

treatments, particularly

acyclovir Aciclovir (ACV), also known as acyclovir, is an antiviral medication. It is primarily used for the treatment of herpes simplex virus infections, chickenpox, and shingles. Other uses include prevention of cytomegalovirus infections following t ...

, have been used in the management of immunocompromised or severely infected patients. It is usually given when the condition fails to improve on its own. Topical acyclovir has not been shown to be effective in management of herpetic whitlow. Famciclovir has been demonstrated to effectively treat and prevent recurrent episodes. Lancing or surgically debriding the

may make it worse by causing a

superinfection A superinfection is a second infection superimposed on an earlier one, especially by a different microbial agent of exogenous or endogenous origin, that is resistant to the treatment being used against the first infection. Examples of this in bact ...

encephalitis Encephalitis is inflammation of the brain. The severity can be variable with symptoms including reduction or alteration in consciousness, headache, fever, confusion, a stiff neck, and vomiting. Complications may include seizures, hallucinations ...

Prognosis

Even though the disease is self-limiting, as with many herpes infections, the virus lies dormant in the peripheral nervous system. The disease recurs in about 20-50% of people. The most severe infection is usually the first one, with recurrences subsequently getting milder. The lesions the disease makes will either dry out, or burst, followed by healing. If the infected area is not touched, scars usually do not occur. The immunocompromised may have a hard time recovering, and have more frequent recurrences.

Gallery

File:Herpetic Whitlow.jpg, Photo of a herpetic whitlow with swelling, erythema, and nonpurulent vesicle formation

References

External links

Herpetic Whitlow

Medscape Medscape is a website providing access to medical information for clinicians; the organization also provides continuing education for physicians and health professionals. It references medical journal articles, Continuing Medical Education (CM ...

* {{DEFAULTSORT:Herpetic Whitlow Herpes simplex virus–associated diseases Virus-related cutaneous conditions Viral diseases