Pityriasis Rosea

views updated May 23 2018

Pityriasis rosea

Definition

Pityriasis rosea is a skin disease of uncertain origin characterized by lesions bordered by collar-like areas that tend to

peel off in tiny scales. Pityriasis comes from the Greek word for bran, pityron, because the flakes of skin shed from the lesions resemble small pieces of wheat bran. Rosea comes from a Latin word that means "rose-colored" or "pink."

Description

Pityriasis rosea is a common benign skin disease, or exanthem, that was first described by a French physician named Camille Gibert in 1860. It is classified as a papulosquamous disorder, which means that its lesions are marked by small raised areas (papules) as well as scaly areas. Pityriasis rosea begins in 60%90% of patients with a pinkish-brown or salmon-colored herald patchsometimes called a mother patchon the chest, back, or neck. The herald patch is a small spot when it first appears, but enlarges over a period of several days to form a circular or oval-shaped area between 3/4-in and 2-1/2 in in diameter. The herald patch develops a scaly border known as a collarette, and is often misdiagnosed in its early stages as eczema or ringworm.

The herald patch is followed within 510 days by a series of similar but smaller oval-shaped patches that appear on the patient's chest, back, and legs, although the general eruption may appear as rapidly as a few hours after the herald patch or as long as three months later. The general rash lasts for about six weeks. The smaller patches range between 1/8 in and 1/2 in in diameter, and are sometimes described as resembling cigarette paper. Lesions on the trunk and abdomen are commonly distributed along the midline of the body in a pattern resembling the outline of a Christmas tree. The lesions of the general eruption are found most commonly on the chest, back, and upper arms, but are sometimes limited to such smaller areas of the body as the armpits, groin, palms of the hands, or feet. Between 9% and 16% of patients develop ulcers or plaques inside the mouth. It is relatively unusual, however, for patches to appear on the face. A small minority of patients may have the herald patch as the only sign of pityriasis rosea.

Pityriasis rosea is a common skin disorder, accounting for 3% of visits to dermatologists in the United States and Canada. The overall prevalence of the disease in the general North American population is thought to be about 0.13% in males and 0.14% in females. It is rare in infants and the elderly; most cases are diagnosed in persons between the ages of 10 and 35. Pityriasis rosea tends to cluster in families, which is one reason why some researchers have been investigating various viruses as possible causes; however, it is not known to spread by casual contact. The disease affects all races and ethnic groups equally.

Pityriasis rosea may occur at any time of year but is most common in temperate climates in the spring and fall.

Causes & symptoms

Causes

The cause of pityriasis rosea is debated as of early 2004. Various researchers have reported isolating a mycoplasma (a type of gram-negative bacterium), a picornavirus, and human herpesviruses 6 and 7 from skin samples of patients diagnosed with the disease, but these findings are not yet considered definitive. Certain medications, including diphtheria vaccines, barbiturates, gold, bismuth compounds, captopril (Capoten), metronidazole (Flagyl), isotretinoin (Accutane), clonidine (Catapres), omeprazole (Prilosec), penicillamine (Cuprimine or Depen), and terbinafine (Lamisil) have been reported to cause skin rashes that resemble the lesions of pityriasis rosea. High levels of emotional stress appear to increase the severity of the skin lesions in some patients.

Symptoms

The most common symptom associated with the lesions of pityriasis rosea is pruritus or itching , which affects about 75% of patients, with 25% reporting severe itching. Many patients find that athletic activity or hot weather makes the itching worse. In addition to pruritus, some patients have prodromal symptoms, which are warning symptoms that occur before the herald patch appears. Prodromal symptoms of pityriasis rosea may include fever , loss of appetite, nausea, headache , joint pains, and swelling of the lymph nodes. Lymph node swelling is more common among African Americans diagnosed with the disease than among Caucasian or Asian Americans.

Diagnosis

The diagnosis of pityriasis rosea is usually made through taking a patient historywith particular attention to prescription medicationsand a skin biopsy ordered by a dermatologist. Although there is no blood test for pityriasis rosea itself, most primary care physicians will order a rapid plasma reagin (RPR) or Venereal Disease Research Laboratory (VDRL) blood test to screen for syphilis . The reason for this precaution is that the lesions of pityriasis rosea resemble the skin rash associated with secondary syphilis. The skin biopsy is done to distinguish between pityriasis rosea and such other skin diseases as lichen planus, psoriasis , ringworm, Kaposi's sarcoma , and seborrheic dermatitis .

Treatment

Pityriasis rosea is a self-limiting disease, which means that it goes away on its own even without alternative or allopathic treatment. Both mainstream physicians and naturopaths, however, recommend adding a cup of oatmeal or baking soda to a tub of warm (not hot) water to minimize itching. In addition, patients whose lesions increase in size or number due to emotional stress may be helped by hydrotherapy, aromatherapy, meditation , or other therapies intended to reduce stress. Massage therapy , however, is contraindicated because the disease usually affects large areas of skin.

Homeopathic practitioners suggest the following remedies for pityriasis rosea, to be taken in 6C potency four times daily for 7 days:

  • Arsenicum. Recommended for patients whose rash is accompanied by anxiety , restlessness, and thirst.
  • Radium bromide. For patients whose lesions are fiery red in color, burning, and painful.
  • Natrum muriaticum. For patients whose lesions have a red appearance under thin white scales, or whose pruritus is made worse by warmth or exercise.

In addition, a homeopathic remedy known as Urtica urens is available in cream or ointment form for direct application to affected areas.

Allopathic treatment

Allopathic treatment of pityriasis rosea is directed toward symptom relief, as the cause of the disease is still uncertain. To relieve the itching, the doctor may prescribe calamine lotion, zinc oxide ointment, oral antihistamine medications, or topical ointments containing corticosteroids or a combination of phenol and 25% menthol. Some physicians prescribe creams containing pramoxine, a local anesthetic. Steroid medications taken by mouth are not recommended unless the pruritus is extremely severe; although these drugs relieve itching, they may also prolong the course of the disease or make the lesions worse.

Some patients are benefited by exposure to sunlight or by treatment with ultraviolet light; however, there is some risk that the skin lesions will develop hyperpigmentation (become darker than the surrounding skin) after ultraviolet treatment. Hyperpigmentation is most likely to occur in African American patients.

There is no need to keep children with pityriasis rosea from attending school, as the disease is not considered contagious.

Expected results

The prognosis for patients with pityriasis rosea is excellent. The disease does not cause long-term health problems, is not dangerous even during pregnancy , and usually clears completely in 68 weeks. A few patients have lesions that last as long as 34 months, but fewer than 3% of patients experience recurrences.

Prevention

As the cause of pityriasis rosea is still debated as of 2004, there are no known preventive measures.

Resources

BOOKS

"Pityriasis Rosea." Section 10, Chapter 117 in The Merck Manual of Diagnosis and Therapy, edited by Mark H. Beers, MD, and Robert Berkow, MD. Whitehouse Station, NJ: Merck Research Laboratories, 2002.

PERIODICALS

Allen, Robert A. MD, and Robert A. Schwartz, MD, MPH. "Pityriasis Rosea." eMedicine, 11 November 2002. <http://www.emedicine.com/derm/topic335.htm>.

Scott, L. A., and M. S. Stone. "Viral Exanthems." Dermatology Online Journal 9 (August 2003): 4.

Stulberg, J. L., and J. Wolfrey. "Pityriasis Rosea." American Family Physician 69 (January 1, 2004): 8791.

Watanabe, T., T. Kawamura, S. E. Jacob, et al. "Pityriasis Rosea Is Associated with Systemic Active Infection with Both Human Herpesvirus-7 and Human Herpesvirus-6." Journal of Investigative Dermatology 119 (October 2002): 793797.

ORGANIZATIONS

American Academy of Dermatology. P. O. Box 4014, Schaumburg, IL 60168-4014. (847) 330-0230. Fax: (847) 330-0050. <http://www.aad.org>.

OTHER

American Academy of Dermatology (AAD). Pityriasis Rosea. Schaumburg, IL: AAD, 2003.

Rebecca J. Frey, PhD

Pityriasis Rosea

views updated May 09 2018

Pityriasis Rosea

Definition

Pityriasis rosea is a mild, noncontagious skin disorder common among children and young adults, and characterized by a single round spot on the body, followed later by a rash of colored spots on the body and upper arms.

Description

Pityriasis rosea is most common in young adults, and appears up to 50% more often in women. Its cause is unknown; however, some scientists believe that the rash is an immune response to some type of infection in the body.

Causes and symptoms

Doctors do not think that pityriasis rosea is contagious, but the cause is unknown. Some experts suspect the rash, which is most common in spring and fall, may be triggered by a virus, but no infectious agent has ever been found.

It is not sexually transmitted, and does not appear to be contagious from one person to the next.

Sometimes, before the symptoms appear, people experience preliminary sensations including fever, malaise, sore throat, or headache. Symptoms begin with a single, large round spot called a "herald patch" on the body, followed days or weeks later by slightly raised, scaly-edged round or oval pink-copper colored spots on the trunk and upper arms. The spots, which have a wrinkled center and a sharp border, sometimes resemble a Christmas tree. They may be mild to severely itchy, and they can spread to other parts of the body.

Diagnosis

A physician can diagnose the condition with blood tests, skin scrapings, or a biopsy of the lesion.

Treatment

The rash usually clears up on its own, although a physician should rule out other conditions that may cause a similar rash (such as syphilis ).

Treatment includes external and internal medications for itching and inflammation. Mild inflammation and itching can be relieved with antihistamine drugs or calamine lotion, zinc oxide, or other mild lubricants or anti-itching creams. Gentle, soothing strokes should be used to apply the ointments, since vigorous rubbing may cause the lesions to spread. More severe itching and inflammation is treated with topical steroids. Moderate exposure to sun or ultraviolet light may help heal the lesions, but patients should avoid being sunburned.

Soap makes the rash more uncomfortable; patients should bathe or shower with plain lukewarm water, and apply a thin coating of bath oil to freshly-dried skin afterwards.

KEY TERMS

Antihistamines A group of drugs that block the effects of histamine, a chemical released during an allergic reaction.

Steroids A group of drugs that includes the corticosteroids, similar to hormones produced by the adrenal glands, and used to relieve inflammation and itching.

Prognosis

These spots, which may be itchy, last for 3-12 weeks. Symptoms rarely recur.

Resources

ORGANIZATIONS

American Academy of Dermatology. 930 N. Meacham Road, P.O. Box 4014, Schaumburg, IL 60168-4014. (847) 330-0230. Fax: (847) 330-0050. http://www.aad.org.

Pityriasis Rosea

views updated Jun 08 2018

Pityriasis rosea

Definition

Pityriasis rosea is a mild skin disorder common among children and young adults, manifesting initially as a single round spot on the body and followed later by a rash of colored spots on the body and upper arms.

Demographics

Pityriasis rosea is most common in young adults and appears up to 50 percent more often in women. The condition occurs most often in spring and fall and can occur in epidemics within dormitories, army barracks, or other locations where young people live in close proximity to each other.

Causes and symptoms

It is unclear whether pityriasis rosea is contagious. Although some experts suspect the rash may be triggered by a virus, no infectious agent had, as of 2004, been found. Some scientists believe that the rash is an immune response to some type of infection in the body.

Sometimes, before the symptoms appear, people experience preliminary symptoms, including fever , malaise, sore throat , or headache . Symptoms begin with a single, large round spot called a herald patch on the body, followed days or weeks later by slightly raised, scaly-edged round or oval pink-copper colored spots on the trunk and upper arms. The distribution of the spots, which have a wrinkled center and a sharp border, sometimes resemble a Christmas tree. They may be mild to severely itchy, and they can spread to other parts of the body.

Diagnosis

Although the diagnosis is usually obvious, if there is any confusion, other conditions (such as a fungal condition or syphilis) can be ruled out through examination of skin scrapings or blood tests.

Treatment

The rash usually clears up on its own, over the course of about 12 weeks. During that time, external and internal medications may be given for itching and inflammation. Mild inflammation and itching can be relieved with antihistamine drugs or calamine lotion, zinc oxide, or other mild lubricants or anti-itching creams. Gentle, soothing strokes should be used to apply the ointments, since vigorous rubbing may cause the lesions to spread. More severe itching and inflammation is treated with topical steroids. Moderate exposure to sun or ultraviolet light may help heal the lesions, but patients should avoid being sunburned.

Soap makes the rash more uncomfortable; patients should bathe or shower with plain lukewarm water and apply a thin coating of bath oil to freshly-dried skin afterwards.

Prognosis

These spots, which may be itchy, last for three to 12 weeks. Symptoms rarely recur.

Parental concerns

After the rash has cleared up, parents often notice that areas where there were spots may appear lighter (hypopigmented) or darker (hyperpigmented) in color than the surrounding skin. Hypopigmentation can be particularly obvious in darker skinned patients. These skin changes will resolve within weeks to months after the rash has cleared.

KEY TERMS

Antihistamine A drug used to treat allergic conditions that blocks the effects of histamine, a substance in the body that causes itching, vascular changes, and mucus secretion when released by cells.

Steroids Hormones, including aldosterone, cortisol, and androgens, that are derived from cholesterol and that share a four-ring structural characteristic.

Resources

BOOKS

"Disease of the Epidermis." In Nelson Textbook of Pediatrics. Edited by Richard E. Behrman et al. Philadelphia: Saunders, 2004.

"Psoriasis and Other Papulosquamous Diseases." In Clinical Dermatology, 4th ed. Edited by Thomas B. Habif. St. Louis, MO: Mosby, 2004.

ORGANIZATIONS

American Academy of Dermatology. 930 N. Meacham Road, PO Box 4014, Schaumburg, IL 601684014. Web site: <www.aad.org>.

Carol A. Turkington Rosalyn Carson-DeWitt, MD

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Pityriasis rosea

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