Monday, April 12, 2010
Varicella
4:43 AM | 
Diposkan oleh
Hermanto
Varicella or chickenpox is an acute disease caused by varicella-zoster virus (VZV) and characterized by generalized vesicular rash.
The incubation period is usually about 7- 14 days and this disease is known to be spread by direct contact. Airborne spread has also been demonstrated especially in hospitals.
Varicella is more common than other childhood diseases during the early months of life. After the first 2 weeks of life, the disease is generally mild. Maternal antibody transferred across the placenta may not be as effective in protecting infants against this disease as antibodies against other viruses.
Varicella is characterized by a generalized eruption that is centripetal in distribution with erythematous macules, papules, vesicles, and scabbed lesions. The vesicles are superficial, with varying amounts of erythema at their bases.
During the early phase of the eruption, lesions are found on the face, scalp, and trunk. Often, lesions can be detected in the scalp before their appearance on the skin by running the fingers through the hair. Later, new lesions appear on the extremities. By this time, the earlier lesions have dried and crusted. Excoriations are common, attesting to the pruritic nature of the lesions.
Mucous membranes of the conjunctiva and oropharynx are more frequently involved in adults than in children. New lesions continue to appear over a 3- or 4-day period, after which the rate of their appearance decelerates markedly.
Most children have a mild illness with few systemic complaints and an average maximal temperature of about 38.3° C. It is more common for adults to have considerable malaise, muscle ache, arthralgia, and headache. These may precede the first skin lesions by 24 to 48 hours.
The most common complication of Varicella is bacterial infections of the skin. The major complications of varicella in adults are encephalitis and pneumonia.
Infection produces a diffuse interstitial type of pneumonia with hypoxia resulting from poor diffusion of gases. Diffuse calcification of the lung parenchyma may be found years after recovery.
Encephalitis in childhood is most commonly manifested by a cerebellitis, which usually occurs at the end of the first week or during the second week after the onset of rash. This complication is almost always self-limited.
To help diagnose, serologic confirmation of the diagnosis can be made using a variety of techniques. The enzyme-linked immunosorbent assay (ELISA) and the latex agglutination assay are the most generally available. The laboratory director should be consulted regarding appropriate time of collection of specimens as well as interpretation of data.
Major therapeutic objectives are the prevention of superinfection and relief of pruritus. To relief pruritus can be accomplished frequently by application of calamine lotion. It is advisable to trim and file nails to reduce the damage from scratching. Bacterial superinfection can best be prevented by encouraging daily bathing with an antibacterial soap.Relief of systemic symptoms may require additional medication such as acetaminophen, although this may increase pruritus.
Antiviral that usually used for adolescent and adults is acyclovir (800 mg per oral five times daily for 5-7 days).
