An update on pityriasis rosea and other similar childhood exanthems John C. Browning Pediatrics and Dermatology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA Correspondence to John C. Browning, MD, FAAP, Assistant Professor, Pediatrics and Dermatology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, MSC 7808, San Antonio, TX 78229, USA Tel: +1 210 562 5344; e-mail: [email protected] Current Opinion in Pediatrics 2009, 21:481–485 Purpose of review Pityriasis rosea is a common skin condition seen in children and adults. Whereas pityriasis rosea is a benign condition, it is important to distinguish it from other childhood exanthems. Recent findings Pityriasis rosea can present in a variety of manners. Most often a herald patch precedes the generalized eruption, although this is not always the case. Pityriasis rosea may lead to undesirable outcomes when affecting pregnant women. Guttate psoriasis, secondary syphilis, cutaneous lupus erythematosus, capillaritis, pityriasis versicolor, nummular eczema, and cutaneous T-cell lymphoma are important to consider in the differential diagnosis of pityriasis rosea. Summary Pityriasis rosea is self-limiting, usually lasting 1–3 months. Treatment may be considered in certain cases, although there is a paucity of medical studies supporting any definitive treatment. However, treatment may be warranted for other conditions that mimic pityriasis rosea. Keywords childhood exanthems, erythromycin, pityriasis rosea, syphilis Curr Opin Pediatr 21:481–485 ß 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins 1040-8703 Introduction Pityriasis rosea is a common rash seen in children and adults. It was first described in 1798 by British physician Robert Willan (1757–1812) under the name roseola annulata . In 1860, the French doctor Camille Melchior Gilbert named the exanthema pityriasis rosea . Since then we have done much to describe the rash of pityriasis rosea but much still remains to be discovered regarding its cause and treatment. Pityriasis rosea derives its name from pityriasis, meaning bran-like, and rosea, meaning pink. In other words, pityriasis rosea is an intelligent-sounding way of saying pink, scaly rash. There are other ‘pityriasis rashes’ such as pityriasis lichenoides, pityriasis alba, pityriasis rubra pilaris, and pityriasis versicolor. Interestingly, other than pityriasis lichenoides, these exanthems are not part of the same family as pityriasis rosea but simply share scaliness as a unifying feature. It was common in the early days of dermatology to name rashes according to their appearance rather than their underlying cause. Epidemiology One study found patients most commonly affected with pityriasis rosea to be between the ages of 10 and 35 years , although it has also been reported in infants , 1040-8703 ß 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins younger children , and the elderly . Pityriasis rosea occurs worldwide and often occurs in the spring and fall. There is no racial or sex predilection. Clinical appearance Classically, pityriasis rosea begins as an erythematous, scaly patch on the trunk known as a herald patch. It is called a ‘herald’ patch because it is heralding the coming of numerous smaller macules and patches. The herald patch is usually several centimeters in size, compared with the typical 1-cm lesions in generalized pityriasis rosea (Fig. 1). The herald patch is often mistaken for tinea corporis, although a simple KOH examination can be done to exclude this diagnosis. Occasionally certain patients will not develop a herald patch prior to the generalized rash, or they may not remember having a herald patch. This may be because the herald patch is asymptomatic and, when located on the back or flank, may not be noticed by the patient. One study found that only 17% of patients develop the herald patch . Although this number is probably low, as it reflects patients with atypical pityriasis rosea seen in a dermatology clinic rather than a primary care clinic, it is helpful to remember that the presence of a herald patch by history is not necessary in making a diagnosis of pityriasis rosea. Days to weeks later, numerous smaller scaly patches DOI:10.1097/MOP.0b013e32832db96e Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 482 Dermatology Figure 1 Numerous erythematous scaly macules on the back following the skin cleavage lines Figure 2 African–American child with inverse pityriasis rosea involving the peri-axillary skin Pityriasis rosea can be mistaken for other exanthems, most commonly pityriasis lichenoides, guttate psoriasis, secondary syphilis, cutaneous lupus, capillaritis, pityriasis versicolor, and nummular eczema. Rarely, cutaneous T-cell lymphoma may be mistaken for pityriasis rosea. These exanthems will be further discussed later in this article. Cause develop on the trunk along the lines of skin cleavage. This has often been described as a Christmas tree pattern because skin-cleavage lines run diagonally on the back . Because of this diagonal pattern, the lesions of pityriasis rosea often have a spindled or football shape to them. The individual patches have a light pink color with slight scale. They are not bright red, as would be seen in a drug eruption, or thick and lichenified, as would be expected with nummular eczema. Pityriasis rosea lasts on average 6–8 weeks, although longer and shorter courses have been reported. In some individuals, pityriasis rosea affects the face and extremities more than the trunk and is referred to as inverse pityriasis rosea (Fig. 2). Pityriasis rosea in patients with darker skin often follows an inverse pattern and may involve the scalp and face, leaving residual pigmentary changes in a majority . Pityriasis rosea may rarely present as a vesicular eruption  or similar to erythema multiforme. . Pityriasis rosea has also been known to involve the oral mucosa , although this is quite rare. There have been reports of purpuric pityriasis rosea [12,13] and unilateral pityriasis rosea . Pityriasis rosea is often mildly pruritic, although in some cases it may be highly pruritic or asymptomatic . The cause of pityriasis rosea is unknown but it has been hypothesized to be due to an infectious agent because of ‘outbreaks’ of pityriasis rosea among certain groups. There has been increasing evidence implicating HHV6 and HHV-7 as causative agents of pityriasis rosea [15,16–18]. There are also many drugs that can cause a pityriasis rosea-like reaction. Some of these include bismuth, captopril, barbiturates, gold, metronidazole, and others. Recently, adalimumab, a monoclonal antibody to tumor necrosis alpha that is used in the treatment of psoriasis and other inflammatory conditions, was reported to induce pityriasis rosea . A recent study has shown that pityriasis rosea during pregnancy can be very dangerous . It may foreshadow premature delivery and even fetal demise. Out of 38 pregnant women with pityriasis rosea, nine had a premature delivery and five miscarried. The greatest risk to the fetus occurred when pityriasis rosea developed in the first 15 weeks of gestation. In one patient in the study who was analyzed in detail, HHV-6 DNA was detected in plasma, skin, peripheral blood mononuclear cells, as well as placental and embryonic tissue. This is important to note so that pregnant women may be appropriately referred to high-risk maternal fetal medicine specialists if they develop pityriasis rosea. Because of difficulties in distinguishing pityriasis rosea from secondary syphilis, Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Update on pityriasis rosea and other similar childhood exanthems Browning 483 pregnant women with pityriasis rosea should have serologic testing for syphilis . Diagnosis Diagnosing pityriasis rosea is nearly always made by history and physical exam alone. In certain atypical cases, a skin biopsy performed by a dermatologist may prove useful in differentiating pityriasis rosea from other exanthems. Histologically, acanthosis with mild psoriasiform hyperplasia and overlying focal parakeratosis may be seen . Treatment Treatment for pityriasis rosea is not necessary since the rash eventually resolves in 1–3 months. Pityriasis rosea is a benign disease, with the exception of potential risks during pregnancy as discussed earlier. However, in certain cases patients may request treatment due to pruritus or cosmetic concerns. One of the most important parts of treatment is to inform the patient and family of the usual 1–3-month course of the rash, its benign and noncontagious nature, and the fact that it is not a reason to be excluded from school or other activities. There has been some evidence that acyclovir may be useful . However, despite its effectiveness against herpes simplex virus, several studies have shown acyclovir to be ineffective against HHV-6 and HHV-7 and instead have shown ganciclovir and foscarnet to be effective antiviral agents [24,25]. This is logical, as HHV-7 lacks the thymidine kinase gene and acyclovir is thymidine kinase-dependent. Interestingly, there has also been one case report of pityriasis rosea occurring during acyclovir therapy . There are no studies investigating the use of foscarnet or ganciclovir in treating pityriasis rosea. In the past there has been support for erythromycin as a treatment for pityriasis rosea . It has been hypothesized that the anti-inflammatory component of erythromycin, rather than the antibiotic effect, is helpful in reducing the inflammation in pityriasis rosea. Recently, however, another study found erythromycin not to be useful in pityriasis rosea . A separate study did not show any benefit in using azithromycin . In response to these studies, a letter to the editor recently commented on unpublished data using clarithromycin in treating pityriasis rosea . Specifically, the author states that 50 out of 52 patients with pityriasis rosea showed improvement during the first week of clarithromycin therapy. The author plans to submit the results of the study in the near future. There has been support in using narrow-band UVB phototherapy [31,32] as well as natural sunlight. Ultraviolet light works by suppressing the cutaneous immune system. Topical steroids offer limited benefit but may be helpful when pruritus is present . Systemic steroids have not been shown to be effective, and the risk of systemic steroids precludes their use in this benign condition. Antihistamines may be of benefit when pruritus is present. Differential diagnosis As mentioned earlier, other exanthems may be mistaken for pityriasis rosea. Pityriasis lichenoides chronica (PLC) has a similar distribution and morphology to pityriasis rosea but does not resolve within the same time period. It can be thought of as ‘pityriasis rosea that does not go away’. PLC can often last for months or years before full resolution. Unlike pityriasis rosea, PLC does not begin with a herald patch, although it tends to primarily involve the trunk (Fig. 3). Histologically, PLC can be differentiated from pityriasis rosea by biopsy, when needed. PLC is characterized histologically by a superficial lymphocytic infiltrate, occasional degenerate keratinocytes, and occasional extravasated erythrocytes . Narrowband UVB phototherapy has been shown to be useful in treating PLC. The acute form of pityriasis lichenoides known as pityriasis lichenoides et varioliformis acuta (PLEVA) lasts for a shorter duration than PLC. PLEVA is characterized by erythematous papules with overlying crusting; it should not be confused with pityriasis rosea. Guttate psoriasis is a form of psoriasis often seen in children following streptococcal illness. It is characterized by round and ovoid scaly, erythematous macules on the trunk. Guttate means ‘drop-like’ because the macules Figure 3 Pityriasis lichenoides chronica Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 484 Dermatology have the appearance of being ‘dropped’ onto the trunk. It can be differentiated from pityriasis rosea by history (lack of a herald patch) and by exam, as the psoriasis macules have thicker scale. The scale can be lifted up to reveal underlying bleeding dermal capillaries, known as Auspitz sign. A recent study found that treating patients with guttate psoriasis with oral penicillin or erythromycin did not result in significant improvement . Streptococcal infection can be a trigger that induces or unmasks an underlying predisposition for psoriasis in certain genetically susceptible children. A study of 277 Chinese children with psoriasis found that nearly 30% had guttate psoriasis . So, although it is not the most common form of psoriasis in children, it remains important in the differential diagnosis of pityriasis rosea. Secondary syphilis is characterized by scaly patches on the trunk similar in appearance to pityriasis rosea. However, syphilis affects the palms and soles and does not begin with a herald patch, distinguishing it from pityriasis rosea. Secondary syphilis can be distinguished histologically by the presence of numerous plasma cells in the skin. A rapid plasma reagin (RPR) and treponemal antibody test are also useful in difficult-to-distinguish cases. The treponemal antibody test is important due to the prozone phenomenon, a false-negative RPR resulting from overwhelming antibody titers [37,38]. This is an especially important diagnosis to consider in adolescent patients who may be engaging in sexual activity. When secondary syphilis is seen in young children, sexual abuse should be highly suspected. Cutaneous lupus may occur with or without systemic lupus erythematosus. One subtype of cutaneous lupus – subacute cutaneous lupus erythematosus (SCLE) – has a similar appearance to pityriasis rosea. It is specifically characterized by erythematous scaly plaques in a photodistribution on the face, neck, and shoulders. Anti-SS-A/ Ro and anti-SS-B/La autoantibodies have been strongly associated with SCLE . SCLE can be distinguished from pityriasis rosea primarily because of its photodistribution. It does not tend to affect covered areas such as the lower chest and back as would be expected with pityriasis rosea. The two diseases can also be easily distinguished by biopsy. Histology of SCLE shows basal vacuolar change, epidermal atrophy, and occasional Civatte bodies . with a ‘cayenne pepper’ appearance on the extremities. Eczematoid-like purpura of Doucas and Kapetanakis is similar to Schamberg’s disease but has overlying scale and pruritus. A skin biopsy can easily distinguish between pityriasis rosea and capillaritis. Pityriasis versicolor, or tinea versicolor as it is also called, is caused by the yeast Malasezia furfur. It is characterized by hypopigmented or hyperpigmented macules with fine scale on the upper chest, back, shoulders, neck, and face. Pityriasis versicolor is more common during the summer months and in tropical climates, as heat and humidity facilitate overgrowth of the yeast. Remission can be easily obtained with treatment using topical or oral antifungal agents, although recurrence is common. Besides its response to treatment, pityriasis versicolor can be distinguished from pityriasis rosea by its distribution (upper trunk, neck, and face), color (hyperpigmented or hypopigmented rather than erythematous), and the presence of finer scale than in pityriasis rosea. The presence of yeast in the stratum corneum can easily be demonstrated on biopsy of pityriasis versicolor. Nummular eczema may be mistaken for pityriasis rosea because of the ‘coin-shaped’ or nummular lesions which are similar in appearance to the lesions of pityriasis rosea. Nummular eczema, however, primarily involves the extremities, whereas classic pityriasis rosea involves the trunk. Nummular eczema is characterized by pruritus and should rapidly improve with topical steroids and emollients. A biopsy will easily demonstrate spongiosis in the epidermis in nummular eczema but not in pityriasis rosea. Cutaneous T-cell lymphoma, or mycosis fungoides as it is also known, initially starts off as a patch stage which can be mistaken for pityriasis rosea. Like pityriasis rosea, cutaneous T-cell lymphoma can be mildly pruritic and is resistant to topical steroids. It is characterized by numerous scaly patches on the trunk and extremities. Biopsy may be helpful, but not always. Often multiple biopsies are required before a diagnosis of cutaneous Tcell lymphoma is made. Cutaneous T-cell lymphoma is far more common in adults than in children but should still be considered in certain pediatric cases . Conclusion Capillaritis is an idiopathic condition in which inflammation of the capillary vessels can lead to leakage of red blood cells into the skin. Clinically this is characterized by nonblanching erythematous patches. There are two subtypes in particular that can be mistaken for pityriasis rosea: Schamberg’s disease and eczematoid-like purpura of Doucas and Kapetanakis. Schamberg’s disease is characterized by nonblanching erythematous patches More studies are needed to understand pityriasis rosea and its cause. Clinical trials are also needed to determine the best treatment for pityriasis rosea. Any study will need to take place over several years or from multiple locations in order to gather enough patients with pityriasis rosea. For now, the best course of action is enthusiastic and repeated reassurance of the patient and family, as well as active nonintervention. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Update on pityriasis rosea and other similar childhood exanthems Browning 485 References and recommended reading Papers of particular interest, published within the annual period of review, have been highlighted as: of special interest of outstanding interest Additional references related to this topic can also be found in the Current World Literature section in this issue (p. 556). 20 Drago F, Broccolo F, Zaccaria E, et al. Pregnancy outcome in patients with pityriasis rosea. J Am Acad Dermatol 2008; 58 (5 Suppl 1):S78–S83. Very important article because it looks at pregnant women with pityriasis rosea and the effects of the illness on the birth outcome. 21 Chuh AA, Lee A, Chan PK. Pityriasis rosea in pregnancy: specific diagnostic implications and management considerations. Aust N Z J Obstet Gynaecol 2005; 45:252–253. 22 Weedon D. The psoriasiform reaction pattern. In: Weedon D, editor. Skin pathology, 2nd ed. London: Churchill Livingstone; 2002. p. 88. 1 Percival GH. Pityriasis rosea. Br J Dermatol Syph 1932; 44:241–253. 2 Gilbert CM. Traite pratique des maladies de la peau et de la syphilis. 3rd ed. Paris: H. Plon; 1860. p. 402. 3 Truhan AP. Pityriasis rosea. Am Fam Physician 1984; 139:489–493. 4 Hendricks AA, Lohr JA. Pityriasis rosea in infancy. Arch Dermatol 1979; 115:896–897. 5 Repiso T, González-Castro U, Luelmo J, et al. Atypical pityriasis rosea in a 2-year-old. Pediatr Dermatol 1995; 12:63–65. 6 Tay YK, Goh CL. One-year review of pityriasis rosea at the National Skin Centre, Singapore. Ann Acad Med Singapore 1999; 28:829–831. 7 Gonzalez LM, Allen R, Janniger CK, Schwartz RA. Pityriasis rosea: an important papulosquamous disorder. Int J Dermatol 2005; 44:757 – 764. 8 Amer A, Fischer H, Li X. The natural history of pityriasis rosea in black American children: how correct is the ‘classic’ description? Arch Pediatr Adolesc Med 2007; 161:503–506. 28 Rasi A, Tajziehchi L, Savabi-Nasab S. Oral erythromycin is ineffective in the treatment of pityriasis rosea. J Drugs Dermatol 2008; 7:35–38. Important because it challenges a long-standing belief that erythromycin is beneficial for patients with pityriasis rosea. 9 Balci DD, Hakverdi S. Vesicular pityriasis rosea: an atypical presentation. Dermatol Online J 2008; 14:6. 29 Amer A, Fischer H. Azithromycin does not cure pityriasis rosea. Pediatrics 2006; 117:1702–1705. 10 Friedman SJ. Pityriasis rosea with erythema multiforme-like lesions. J Am Acad Dermatol 1987; 17:135–136. 30 Bukhari IA. Oral erythromycin is ineffective in the treatment of pityriasis rosea. J Drugs Dermatol 2008; 7:625. 11 Vidimos AT, Camisa C. Tongue and cheek: oral lesions in pityriasis rosea. Cutis 1992; 50:276–280. 31 Arndt KA, Paul BS, Stern RS, Parrish JA. Treatment of pityriasis rosea with UV radiation. Arch Dermatol 1983; 119:381–382. 12 Chuh A, Zawar V, Lee A. Atypical presentations of pityriasis rosea: case presentations. J Eur Acad Dermatol Venereol 2005; 19:120– 126. 32 Leenutaphong V, Jiamton S. UVB phototherapy for pityriasis rosea: a bilateral comparison study. J Am Acad Dermatol 1995; 33:996–999. 13 Sezer E, Saracoglu ZN, Urer SM, et al. Purpuric pityriasis rosea. Int J Dermatol 2003; 42:138–140. 14 Brar BK, Pall A, Gupta RR. Pityriasis rosea unilateralis. Indian J Dermatol Venereol Leprol 2003; 69:42–43. 15 Canpolat Kirac B, Adisen E, Bozdayi G, et al. The role of human herpes virus 6, human herpes virus 7, Epstein-Barr virus and cytomegalovirus in the aetiology of pityriasis rosea. J Eur Acad Dermatol Venereol 2008. [Epub ahead of print] Important because of the role of viruses in pityriasis rosea. 16 Drago F, Ranieri E, Malaguti F, et al. Human herpes virus 7 in pityriasis rosea. Lancet 1997; 349:1367–1368. 17 Watanabe T, Kawamura T, Jacob SE, et al. Pityriasis rosea is associated with systemic active infection with both human herpesvirus-7 and human herpesvirus-6. J Invest Dermatol 2002; 119:793–797. 18 Broccolo F, Drago F, Careddu AM, et al. Additional evidence that pityriasis rosea is associated with reactivation of human herpesvirus-6 and -7. J Invest Dermatol 2005; 124:1234–1240. 19 Rajpara SN, Ormerod AD, Gallaway L. Adalimumab-induced pityriasis rosea. J Eur Acad Dermatol Venereol 2007; 21:1294–1296. 23 Drago F, Vecchio F, Rebora A. Use of high-dose acyclovir in pityriasis rosea. J Am Acad Dermatol 2006; 54:82–85. 24 Zhang Y, Schols D, De Clercq E. Selective activity of various antiviral compounds against HHV-7 infection. Antiviral Res 1999; 43:23–35. 25 De Clercq E, Naesens L, De Bolle L, et al. Antiviral agents active against human herpesviruses HHV-6, HHV-7 and HHV-8 [review]. Rev Med Virol 2001; 11:381–395. 26 Mavarkar L. Pityriasis rosea occurring during acyclovir therapy. Indian J Dermatol Venereol Leprol 2007; 73:200–201. 27 Sharma PK, Yadav TP, Gautam RK, et al. Erythromycin in pityriasis rosea: a double-blind, placebo-controlled clinical trial. J Am Acad Dermatol 2000; 42 (2 Pt 1):241–244. 33 Stulberg DL, Wolfrey J. Pityriasis rosea [review]. Am Fam Physician 2004; 69:87–91. 34 Weedon D. The vasculopathic reaction pattern. In: Weedon D, editor. Skin pathology, 2nd ed. London: Churchill Livingstone; 2002. p. 247. 35 Dogan B, Karabudak O, Harmanyeri Y. Antistreptococcal treatment of guttate psoriasis: a controlled study. Int J Dermatol 2008; 47:950–952. 36 Fan X, Xiao FL, Yang S, et al. Childhood psoriasis: a study of 277 patients from China. J Eur Acad Dermatol Venereol 2007; 21:762–765. 37 Smith G, Holman RP. The prozone phenomenon with syphilis and HIV-1 coinfection. South Med J 2004; 97:327–328. 38 Battistella M, Le Cleach L, Lacert A, Perrin P. Extensive nodular secondary syphilis with prozone phenomenon. Arch Dermatol 2008; 144:1078–1079. 39 Stavropoulos PG, Goules AV, Avgerinou G, Katsambas AD. Pathogenesis of subacute cutaneous lupus erythematosus [review]. J Eur Acad Dermatol Venereol 2008; 22:1281–1289. 40 Weedon D. The lichenoid reaction pattern (‘interface dermatitis’). In: Weedon D, editor. Skin pathology, 2nd ed. London: Churchill Livingstone; 2002. p. 50. 41 Tsianakas A, Kienast AK, Hoeger PH. Infantile-onset cutaneous T-cell lymphoma [review]. Br J Dermatol 2008; 159:1338 – 1341. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
© Copyright 2019