Pityriasis lichenoides in children: a long-term follow-up of eighty-nine cases

Narrowband ultraviolet B phototherapy for pityriasis lichenoides: A real-life experience

INTRODUCTION

Pityriasis lichenoides (PL) is a papulosquamous disease affecting both children and adults, for which narrowband-UVB (NB-UVB) phototherapy is regarded as a commonly used treatment option. The aim of this study was to investigate the efficacy of NB-UVB phototherapy in the management of PL and to compare response rates in pediatric and adult age groups.

MATERIALS AND METHODS

This observational, retrospective study included 20 PL patients (12 pityriasis lichenoides chronica; PLC, 8 pityriasis lichenoides et varioliformis acuta; PLEVA) who failed to respond to other treatment modalities. The data for this study were collected retrospectively from patient follow-up forms in the phototherapy unit.

RESULTS

A complete response (CR) was obtained in all pediatric patients with PL, while 53.8% of adult patients had achieved CR. The mean cumulative dose required to achieve the CR was higher in pediatric patients than adult patients with PL (p < .05). The CR was achieved in 6 (75%) of 8 PLEVA patients, while 8 (66.7%) of 12 PLC patients had reached to CR. The mean number of exposures for patients with PLC to achieve a CR was higher than patients with PLEVA (p < .05). Erythema was the most common adverse effect during phototherapy particularly in 5 (35.7%) of the patients with PL who had achieved CR.

CONCLUSIONS

NB-UVB is an effective and well-tolerated treatment option for PL especially in diffuse types. A higher response can be obtained in children with higher cumulative dose. Patients with PLC may require more exposures for CR than patients with PLEVA.

Hypopigmented lesions in pityriasis lichenoides chronica patients: Are they only post-inflammatory hypopigmentation?

BACKGROUND/OBJECTIVES

Pityriasis lichenoides chronica (PLC) lesions are reported to subside with post-inflammatory hypopigmentation (PIH); hence, the most widely perceived nature of hypopigmented macules in PLC is PIH. However, to the best of our knowledge, no studies describing histopathological findings in these lesions are reported in literature. The aim of this study is to evaluate the hypopigmented lesions encountered in PLC patients and to shed light on their histopathological features.

METHODS

A cross-sectional observational study included twenty-one patients with PLC recruited in a period of twelve months. Clinical characteristics of each patient were collected. A skin biopsy from hypopigmented lesions whenever present was taken and assessed with routine haematoxylin and eosin stain.

RESULTS

Seventeen patients (81%) were less than 13 years old. Most patients (85.7%) demonstrated diffuse distribution of lesions. Hypopigmented lesions were present on the face in 12 (57.14%) patients. Histopathologically, hypopigmented lesions showed features of post-inflammatory hypopigmentation in 19% of patients, residual PLC in 52.4% and active PLC 28.6% of patients.

CONCLUSION

Hypopigmented lesions in PLC were noted mainly in younger ages, histopathologically they may show features of active or residual disease, beyond post-inflammatory hypopigmentation. Consequently active treatment for patients presenting predominantly with hypopigmented lesions could be required to control the disease.

Pityriasis lichenoides: a clinical and pathological case series of 49 patients with an emphasis on follow-up

The classification of pityriasis lichenoides (PL) into pityriasis lichenoides et varioliformis acuta (PLEVA), PL chronica (PLC) or febrile ulceronecrotic Mucha-Habermann disease (FUMHD) mixes clinical and chronological features. In this retrospective monocentric study, we aimed to investigate the relevance of the classification in routine practice. We included 49 patients (25 women, median age 41 years). The lesions were papular in 76% of patients, necrotic in 12%, and mixed in 12%. We found three histological patterns: "classical" (65%), "lymphomatoid" (13%), and "mild" (22%). The "lymphomatoid" pattern was associated with necrotic presentation and the "mild' pattern with papular lesions (p=0.012). Among the 27 patients with follow-up, 18% had relapses and 44% a chronic form. One patient had mycosis fungoides. Neither clinical nor histological aspects were correlated with disease progression. Clinical and histological pictures reflect more the intensity of epidermal injury rather than disease course. "Pityriasis lichenoides" should be preferred to the classical PLEVA/PLC classification.

Pityriasis in dermatology: an updated review

Dermatology has a very distinctive lexicon. The term pityriasis refers to several dermatologic conditions which all feature scaling of the skin. According to the Merriam-Webster dictionary, the term pityriasis was first used in print in 1684. Although the diseases beginning with the name pityriasis are of diverse causation, they do represent important dermatologic diseases, with some common and others quite rare. It is important for dermatologists to be aware and updated on all pityriasis conditions in dermatology.

Oral erythromycin in pityriasis lichenoides chronica and pityriasis lichenoides et varioliformis acuta

Pityriasis lichenoides (PL) is an uncommon cutaneous disorder. Oral erythromycin is proposed to be effective in treating the disease. Here, we reported 16 pediatric patients with PL and systematically reviewed published literatures on erythromycin treatment response in pediatric PL patients, to observe the different treatment response to erythromycin in the pityriasis lichenoides chronica (PLC) and the pityriasis lichenoides et varioliformis acuta (PLEVA) groups. Sixteen patients, 8 with PLC and 8 with PLEVA, were treated with erythromycin. In the PLC group, 25% (n = 2) patients responded to erythromycin, while in the PLEVA group, 87.5% (n = 7) patients responded to erythromycin. The response rate was higher in the PLEVA group than the PLC group (P =.05). No side effect was reported in the 16 patients. A total of 34 children including 16 from our studies were included for further descriptive analysis, in which 12 had PLC and 22 had PLEVA. In the PLC group, 41.7% (n = 5) of patients responded to erythromycin while in the PLEVA group, 90.9 % (n = 20) of patients responded. The response rate was higher in the PLEVA group than the PLC group (P = .004). In conclusion, erythromycin is effective and safe in the treatment of children with PL, and erythromycin was more effective in patients with PLEVA than PLC.

Systematic review of the efficacies and adverse effects of treatments for pityriasis lichenoides

BACKGROUND

Pityriasis lichenoides (PL) is a papulosquamous dermatosis affecting both children and adults, for which no standard treatment currently exists.

OBJECTIVES

To characterize different treatment options and develop an evidence-based treatment algorithm for PL.

METHODS

A systematic search of published literature on PL treatments was performed on 23 December 2017 via the MEDLINE, Embase, CINAHL, CENTRAL, ClinicalTrials.gov and the EU Clinical Trials Register databases.

RESULTS

Of 1090 abstracts retrieved, 27 full-text articles with 502 participants were included for analysis. Seventeen of the full-text articles were retrospective cohort studies and two were randomized controlled studies. Treatment modalities included in these articles were phototherapy, antibiotics, methotrexate, pyrimethamine and trisulfapyrimidine, corticosteroids and conservative treatment. Of these treatments, phototherapy led to complete remission in the highest proportion of patients, and topical corticosteroids were found to have been trialled in the highest number of patients.

CONCLUSIONS

The current literature consists almost entirely of uncontrolled studies, and none provides compelling data to support an evidence-based approach to PL treatment. Pityriasis lichenoides chronica and pityriasis lichenoides et varioliformis acuta should be distinguished in response to treatment, and definitions of response to treatment must be standardized. Additional randomized control studies with longer follow-up will help better differentiate between treatment efficacies and adverse effects.

Relationship Between Pityriasis Lichenoides and Mycosis Fungoides: A Clinicopathological, Immunohistochemical, and Molecular Study

BACKGROUND

Several cases of pityriasis lichenoides (PL) have been reported to evolve into mycosis fungoides (MF).

OBJECTIVE

To elucidate clues to this progression.

METHODS

Fifty-eight patients with PL between 2000 and 2013 (follow-up: 3-16 years, average: 8.3).

RESULTS

A total of 3 (5.2%) of the 58 patients with PL developed MF after 3-11 years of prolonged clinical course. Papules and small plaques characterized PLs, and patches and larger plaques subsequent MFs. A total of 35 of 41 (85%) followed up non-MF associated patients with PL reported lasting complete remissions. Histopathologically, apoptotic keratinocytes disappeared mostly or completely in subsequent MFs. The presence of epidermotropism, folliculotropism, and epidermal lymphocytic nuclear atypia in PLs was not predictive of MF. CD8 cells were the dominant intraepidermal lymphocytes in the 3 PLs but remained so in only 1 subsequent MF. CD7 lymphocytes decreased substantially in 2 MFs, and lymphocytic nuclear atypia increased markedly in 1. T-cell receptor gene rearrangement studies demonstrated clonal populations in 1 of 2 studied PLs and in all 3 subsequent MFs.

CONCLUSIONS

A few PLs may evolve into MF. Prolonged clinical course, appearance of patches and larger plaques, markedly increased lymphocytic nuclear atypia, marked diminution of apoptotic keratinocytes and CD7 and CD8 lymphocytes, and clonal T-cell receptor gene rearrangement may serve as clues.

Pityriasis lichenoides: Long-term follow-up study

BACKGROUND/OBJECTIVES

Pityriasis lichenoides is an uncommon papulosquamous disorder of unknown etiology. The objective of this study was to review the clinical features and treatment responses of individuals with pityriasis lichenoides seen at a tertiary referral center.

METHODS

Seventy-five patients diagnosed with pityriasis lichenoides between 1997 and 2013 were reviewed, and 46 had long-term follow-up via telephone interviews.

RESULTS

Fifty (67%) patients were diagnosed with pityriasis lichenoides chronica, 22 (29%) with pityriasis lichenoides et varioliformis acuta, and 3 (4%) with mixed pityriasis lichenoides chronica and pityriasis lichenoides et varioliformis acuta features. Mean ± standard deviation age at onset was 12 ± 13 years (median 8 years). Disease duration was significantly shorter for patients with pityriasis lichenoides et varioliformis acuta (35 ± 35 months) than for those with pityriasis lichenoides chronica (at least 78 ± 48 months). At long-term follow-up, 23 of 28 (82%) patients with pityriasis lichenoides chronica and 3 of 16 (19%) with pityriasis lichenoides et varioliformis acuta had active disease. None progressed to lymphomatoid papulosis or cutaneous T-cell lymphoma. Ten of 23 active pityriasis lichenoides chronica cases had residual pigmentary change independent of race and lasted at least 35 ± 20 months. The most effective treatments were phototherapy (47% response rate), heliotherapy (33%), topical corticosteroids (27%), and antibiotics (25%).

CONCLUSION

Pityriasis lichenoides is a predominantly pediatric disorder. The time course of pityriasis lichenoides chronica is significantly longer than that of pityriasis lichenoides et varioliformis acuta. Pityriasis lichenoides chronica may persist with pigmentary alterations in the absence of other signs of active inflammation. Treatment response is often limited, particularly for patients with pityriasis lichenoides chronica.

Use of Phototherapy in Children

BACKGROUND

Phototherapy is a well-recognized treatment in adults and children. Previous articles have reported success in treating recalcitrant skin disorders such as atopic dermatitis (AD), psoriasis, pityriasis lichenoides chronica, and vitiligo in children.

METHODS

This was a retrospective review over an 18-month period from June 2012 to December 2013 of all children receiving phototherapy in a tertiary pediatric dermatology center.

RESULTS

Seventy-five patients 3 to 17 years of age (mean 10.6 years; 35 male, 40 female) were included. Forty-eight (64%) patients had AD and 21 (28%) had psoriasis. Seventy received narrowband ultraviolet B (NBUVB) treatment and five received hand and foot psoralen and ultraviolet A (PUVA) treatment. All patients with AD were treated with NBUVB and four (8.3%) were also treated with hand PUVA. After phototherapy, 76% had documented clear to almost clear skin. At the 12-month follow-up, 52% of the patients with AD remained clear. All 21 patients with psoriasis underwent NBUVB phototherapy. The clearance rate after phototherapy was 86%. At the 12-month follow-up, 43% of the patients with psoriasis remained clear.

CONCLUSION

Phototherapy can reduce disease burden in individuals with severe AD and psoriasis and should be considered as a second-line therapy if standard topical regimens are unsuccessful.

Phototherapy for Pityriasis Lichenoides in the Pediatric Population: A Review of the Published Literature

BACKGROUND

Pityriasis lichenoides (PL) is a dermatologic disorder that manifests in either the acute (pityriasis lichenoides et varioliformis acuta) or the chronic form (pityriasis lichenoides chronica, also known as parapsoriasis chronica). Traditional first-line therapy consists of corticosteroids or antibiotics; however, these treatments are often accompanied with multiple side effects and may be ineffective.

OBJECTIVE

The goal of this study was to review the use of phototherapy for treating PL in the pediatric population.

MATERIALS AND METHODS

We performed a systematic review of the literature in the National Library of Medicine's PubMed database and the SCOPUS database discussing phototherapy for treatment of PL in the pediatric population. The following search terms were used: 'pityriasis lichenoides', 'pityriasis lichenoides chronica', 'pityriasis lichenoides et varioliformis acuta', and 'febrile ulceronecrotic Mucha-Habermann disease'.

RESULTS

The systematic search and screening of articles resulted in 14 articles including a total of 64 patients with PL treated with phototherapy. Three different modalities were utilized, with five studies using broadband ultraviolet B (BB-UVB) radiation, nine studies utilizing narrowband UVB (NB-UVB), and two studies employing psoralen with ultraviolet A (PUVA) therapy. Overall, the use of BB-UVB had an initial clearance rate of 89.6 % with 23.1 % recurrence, whereas NB-UVB cleared 73 % of the lesions with no recurrence, and PUVA therapy initially cleared 83 % of the lesions with 60 % recurrence. The side-effect profiles were similar and revealed limited toxicity.

CONCLUSION

Phototherapy shows promising results and a favorable side-effect profile in the treatment of PL. Ultimately, large randomized controlled trials are needed to determine optimal treatments.

Phototherapy in children: Considerations and indications

Phototherapy can be a safe and effective treatment for various skin diseases in children. Special considerations governing the use of this treatment modality in pediatric populations include patient, family, and facility-based factors that are oriented around heightened concerns with regard to safety and tolerability of treatment. Although phototherapy has been found to be effective in a wide range of dermatologic conditions affecting pediatric populations, including psoriasis, atopic dermatitis, pityriasis lichenoides, cutaneous T-cell lymphoma, and vitiligo, there is need for additional research on other conditions in which phototherapy has shown promise.

Pityriasis lichenoides et varioliformis acuta after influenza vaccine

The etiology of pityriasis lichenoides is unknown. One of the accepted theories admits that PL is an inflammatory response to extrinsic antigens such as infectious agents, drugs and vaccines. In recent medical literature, only the MMR vaccine (Measles, Mumps and Rubella) was associated with the occurrence of this disease. We present a case of a male, 12 year old healthy patient who, five days after Infl uenza vaccination, developed erythematous papules on the trunk, abdomen and limbs, some with adherent crusts and associated systemic symptoms. This case report is notable for describing the first case of pityriasis lichenoides et varioliformis acuta associated with the vaccine against Influenza.

Pityriasis Lichenoides in Childhood: Review of Clinical Presentation and Treatment Options

Pityriasis lichenoides (PL) is a skin condition of unclear etiology that occurs not uncommonly in childhood. It is often classified into the acute form, pityriasis lichenoides et varioliformis acuta (PLEVA), and the chronic form, pityriasis lichenoides chronica (PLC). We performed a comprehensive review of the English-language literature using the PubMed database of all cases of childhood PL reported from 1962 to 2014 and summarized the epidemiology, clinical features, treatment options, and prognosis of this condition in children. The proposed etiologies are discussed, including its association with infectious agents, medications, and immunizations and evidence for PL as a lymphoproliferative disorder. We found an average age of PL onset of 6.5 years, with a slight (61%) male predominance. We also found that PLEVA and PLC tend to occur with equal frequency and that, in many cases, there is clinical and histopathologic overlap between the two phenotypes. When systemic therapy is indicated, we propose that oral erythromycin and narrowband ultraviolet B phototherapy should be first-line treatment options for children with PL since they have been shown to be effective and well tolerated. In most cases, PL follows a benign course with no greater risk of cutaneous T-cell lymphoma, although given the rare case reports of transformation, long-term follow-up of these patients is recommended.

Childhood pityriasis lichenoides and oral erythromycin

Pityriasis lichenoides (PL) is not uncommon in childhood, but current knowledge about the efficacy of oral erythromycin therapy for its treatment in children is limited. To investigate the role of oral erythromycin therapy in the treatment of PL in children, the records of 24 children with PL who had been started on oral erythromycin treatment at our institution between 2005 and 2008 were retrospectively reviewed. The study included 24 patients (14 male, 10 female) with a median age of 7 years (range 2-14) of whom 15 (62.5%) had PL chronica (PLC), six (25%) PL et varioliformis acuta (PLEVA), and three (2.5%) PLEVA-PLC overlap. History of upper respiratory tract infection was reported in 33% (n = 8) of the patients. History of drug intake and vaccination was noted in 20% (n = 5) and 20% (n = 5), respectively. The disease began during spring (30%, n = 7) or fall (30%, n = 7) in the majority of patients. The median duration of the disease was 11 months (range 1-48 months). Fifteen (68.2%) patients had more than 100 lesions. Distribution was diffuse in 82% (n = 18) of the cases and peripheral in the remainder (n = 6). Oral erythromycin was started at a dosage of 30 to 50 mg/kg per day in three to four divided dosages for 1 to 4 months. Good response was recorded in 64% and 73% of patients in the first and second months of therapy, respectively. Response rate rose to 83% in the third month. In those for whom follow-up data were available (n = 16), relapse was recorded in 12.5% (n = 3). Oral erythromycin may be an effective and well-tolerated treatment option for PL in children and should be continued for at least 3 months.

Phototherapy for pityriasis lichenoides: our experience

Pityriasis lichenoides is a benign disease that includes a continuous spectrum with two polar ends: pityriasis lichenoides et varioliformis acuta (PLEVA) and pityriasis lichenoides chronica (PLC). Although its benign and self-limited character, treatment is required, both for itch relief and for cosmetic issues. The present study is a retrospective analysis of 13 patients (11 PLC and 2 PLEVA) treated in our institution with psoralen plus ultraviolet A (PUVA) or ultraviolet A combined with ultraviolet B (UVA/UVB) during the period 1998-2011. In the PUVA group, complete response was achieved in five patients and partial response in two. Total cumulative UVA dose was 84.4 J/cm(2). One patient quit therapy without therapeutic response. In the UVA/UVB group, complete response was achieved in two patients and partial response in an equal number of patients. One patient did not reach a significant improvement. Total cumulative doses were: 26.1 J/cm(2) for UVA and 3.62 J/cm(2) for UVB. There were no acute side effects in either therapeutic group. In the present study, PUVA phototherapy was preferred for patients with more widespread or long-evolving disease, while UVA/UVB was selected for patients who presented more recent disease or contraindications for PUVA therapy. Regardless of the absence of clinical guidelines, both therapeutic options proved to be successful, ascertaining phototherapy as an effective and safe option for pityriasis lichenoides patients.

Assessment of the 'no eosinophils' rule: are eosinophils truly absent in pityriasis lichenoides, connective tissue disease, and graft-vs.-host disease?

Eosinophils are often present in the inflammatory infiltrate of an interface dermatitis, but the diagnostic specificity of eosinophils in interface dermatitis has not been formally evaluated. We retrospectively identified 97 examples of interface dermatitis with clinically confirmed diagnoses, including lupus erythematosus (LE), lichen planus, pityriasis lichenoides (PL), graft-vs.-host disease (GVHD), dermatomyositis (DM) and drug reaction. Diagnoses were clinically confirmed by at least two dermatologists. Slides were reviewed in a blinded fashion by at least two dermatopathologists. The average eosinophil count per 10 ×200 (×20 objective) fields was lowest for PL (0.2), DM (0.3), GVHD (0.4), and LE (0.5) [defined as Group 1] and was higher for lichen planus, drug reactions, erythema multiforme (major and minor) and viral exanthems [defined as Group 2]. Distinction between Group 1 and Group 2 was maximized using an eosinophil count cutoff of 1.1. In conclusion, eosinophils are usually rare to absent in PL, DM, most forms of LE and GVHD. While final interpretation requires a composite assessment of all features, our results suggest that the presence of even a single eosinophil within nine or ten ×20 fields argues against a diagnosis of PL, DM or LE.

Narrowband ultraviolet-B phototherapy in pityriasis lichenoides chronica

BACKGROUND

Current knowledge about the efficacy of narrowband UVB therapy for the treatment of pityriasis lichenoides is limited.

OBJECTIVE

The aim of this study was to investigate the efficacy of narrowband UVB therapy for the treatment of pityriasis lichenoides chronica (PLC).

METHODS

Data were retrospectively collected following a review of patient phototherapy and medical charts, and telephone interviews were performed for follow-up information.

RESULTS

The study included 25 patients (14 male, 11 female) with a mean age of 34 +/- 13 years. Diagnosis was confirmed by histopathological examination in 92% (n = 23) of the patients. The median duration of the disease was 24 months (range: 2-192 months). The median number of sessions until response was 25 (8 weeks) (range: 9-77 sessions), with a median cumulative dose of 15 J/cm(2) (range: 2-158 J/cm(2)). Complete response and partial response were achieved in 48% and 44% of the patients, respectively, while 8% of the patients achieved no response. In those patients for whom follow-up data were available (n = 17), 10 (58%) relapsed within a median of 9.5 months (range: 1-44 months).

CONCLUSIONS

Our results suggest that narrowband UVB is an effective and well-tolerated treatment option for PLC.

Phototherapy in childhood

BACKGROUND

Little data exist about the efficacy of phototherapy in childhood dermatoses.

OBJECTIVE

To report our experience with pediatric patients treated with phototherapy.

METHODS

The study included children <or=17 years of age, who were treated in our phototherapy unit between 1985 and 2005. Data were retrospectively collected.

RESULTS

The study included 113 patients (50 boys, 63 girls) with a median of age of 13 years (range: 3-17 yrs). Narrow-band ultraviolet-B (34.6%), and ultraviolet-B (33.1%) were the most common treatments administered to the patients. Indications for phototherapy were psoriasis in 53.5%, vitiligo in 20.5%, pityriasis lichenoides in 14.2%, alopecia areata in 7.9%. Response was achieved in 92.9% of the psoriasis patients treated with narrow-band ultraviolet-B, in 83.3% treated with psoralen plus ultraviolet-A, and in 93.3% with ultraviolet-B. All the pityriasis lichenoides chronica patients who received narrow-band ultraviolet-B responded to the treatment and seven of nine treated with ultraviolet-B had a response. Response was achieved in 57% of the vitiligo patients treated with psoralen plus ultraviolet-A and in 50% of vitiligo patients treated with narrow-band ultraviolet-B. Of the 10 alopecia areata patients, two responded to psoralen plus ultraviolet-A. Among all the patients, erythema was the most common adverse effect.

CONCLUSION

Phototherapy is a well-tolerated treatment for childhood dermatoses, and is especially efficacious in psoriasis and pityriasis lichenoides chronica patients.

Parapsoriasis: a complex issue

Parapsoriasis is a peculiar reaction pattern of the skin that appears to have a spectrum with small plaque parapsoriasis at one end and large plaque at the other. The spectrum between is bridged by pityriasis lichenoides, pityriasis lichenoides chronica, pityriasis lichenoides et varioliformis acuta, and lymphomatoid papulosis. The highlights of the clinical pattern of these diseases has been succinctly elucidated here to facilitate their recognition in day-to-day dermatologic practice. Their possible etiopathogenesis has been brought to focus in the light of changing concepts reported in the literature. Further, possible future implications demand a meticulous follow-up because, in a few cases, true neoplasms may ultimately develop. Treatment modalities are briefly discussed.

Pityriasis lichenoides: the differences between children and adults

BACKGROUND

Pityriasis lichenoides (PL) is a skin disease that affects both children and adults. Anecdotally, it is said to run a more benign course in children, with a frequent tendency to self-resolution. However, to our knowledge, there have been no published studies comparing PL in both age groups.

OBJECTIVE

To evaluate the clinicopathological features, overall efficacy of treatments and disease outcomes in children and adults diagnosed with PL.

METHODS

A retrospective review of records was undertaken on all patients diagnosed with PL at two regional centres during an 8-year period (from 1998 to 2006). For each individual, data were collected on age, sex, number of lesions, lesional morphology and distribution, symptoms, histopathological features, treatment modalities (and response), overall follow-up and length of remission.

RESULTS

We recorded 25 children (median age 8 years, range 2-18) and 32 adults (median age 40 years, range 20-65) with PL. All the children and adults had more than 20 scaly, papular lesions. Children had greater lesional body involvement than adults. Lesions on the legs and trunk were present in 23 children (92%) compared with 19 adults (59%) (P < 0.01) and facial involvement was observed more commonly in children (n = 10, 40%) compared with adults (n = 8, 25%). Dyspigmentation was significantly more common in children (n = 18, 72%) compared with adults (n = 6, 19%) (P < 0.001). Topical corticosteroids were used by 16 children (64%) and 18 adults (56%) but only half in each group found these effective. Eight children (32%) were treated with erythromycin, with only two (25%) clearing, and one of these subsequently relapsing. In contrast, four adults (13%) received antibiotics, with three (75%) clearing and none relapsing thereafter. Ultraviolet B phototherapy was used in eight children (32%), with seven (88%) completely or almost clearing, but four (57%) subsequently relapsed. Fourteen adults (44%) received phototherapy; 10 (71%) completely cleared and only two of these (20%) subsequently relapsed. Strikingly, after a median disease duration of 30 months, only five children (20%) went into complete remission compared with 25 adults (78%) (P < 0.001).

CONCLUSIONS

This is the first study to compare PL in children and adults. Our findings suggest that, compared with adults, PL in children is more likely to run an unremitting course, with greater lesional distribution, more dyspigmentation and a poorer response to conventional treatment modalities.

Pediatric pityriasis lichenoides and cutaneous T-cell lymphoma

PURPOSE OF REVIEW

The purpose of this review is to educate the reader about two cutaneous lymphoproliferative diseases in childhood: pityriasis lichenoides and cutaneous T-cell lymphoma. Pityriasis lichenoides has traditionally been divided into acute and chronic subtypes. The two forms of the disease, however, are best thought of as two ends of a benign lymphoproliferative spectrum. Cutaneous T-cell lymphoma is a rare but underrecognized cutaneous malignancy in children. Early stage disease and hypopigmented presentation are characteristic of pediatric cutaneous T-cell lymphoma. The optimal investigation and treatment plans are still controversial.

RECENT FINDINGS

This article will summarize recent articles on pityriasis lichenoides and pediatric cutaneous T-cell lymphoma, including recent findings from an international registry of pediatric cutaneous T-cell lymphoma.

SUMMARY

After reading this review, the reader should be able to recognize the clinical presentation of pityriasis lichenoides, to understand the overlap between its acute and chronic forms, and to recognize its relationship with cutaneous T-cell lymphoma. In addition, the reader will appreciate the challenges in diagnosing and treating pediatric cutaneous T-cell lymphoma.

[Localized pityriasis lichenoides]

Pitiryasis lichenoides is a papulosquamous disorder of unknown etiology frequently seen in the pediatric population. The lesions are usually widespread on the trunk and extremities, and only exceptional cases of localized forms have been reported. We report a 9-year-old patient with recurrent crops of pitiryasis lichenoides lesions exclusively involving the lower abdomen.

Pityriasis lichenoides in childhood: A retrospective review of 124 patients

BACKGROUND

Pityriasis lichenoides (PL) occurs in all age groups, although predominantly in younger individuals.

OBJECTIVE

We sought to study the clinical features of PL in children followed up at our institution.

METHODS

The records of 124 children who were given the diagnosis of PL at our institution between 1993 and 2003 were retrospectively reviewed.

RESULTS

PL chronica (PLC) was recorded in 37% of the cases, PL et varioliformis acuta (PLEVA) in 57.3%, and clinical features of both disorders were seen simultaneously in the remaining. The median age of onset was 60 months (range: 6-180 months), although the median age of onset of PLEVA (median: 60 months) was significantly younger than that of PLC (median: 72 months) (P = .03). The age distribution showed peaks at 2 to 3 years (24.8%) and 5 to 7 years (32%). A history of infection or drug intake preceded the skin manifestations in 30% and 11.2% of patients with PLC and PLEVA, respectively. The disease began most commonly during winter (35%) or fall (30%). The median duration was 20 months (range: 3-132 months) in patients with PLC and 18 months (range: 4-108 months) in patients with PLEVA. Involvement was diffuse in 74.2% of the patients, peripheral in 20.2%, and central in the remainder. The disease was recurrent in 77% of the patients (n = 80). Of the patients, 59% had pruritus, whereas 32% reported no symptoms; the remainder had fever, arthralgia, or both. Erythromycin estolate or ethylsuccinate was administered to 79.7% of the affected children; 66.6% of these showed at least a partial response.

LIMITATIONS

The analyzed data were collected retrospectively and biopsies were not performed in all patients.

CONCLUSIONS

PL is not an uncommon disease in childhood, with age peaks in the preschool and early school-age years. It is usually recurrent, and shows a seasonal variation with onset most often in the fall or winter. In childhood PL, erythromycin is an effective initial treatment choice.

Pityriasis lichenoides: pathophysiology, classification, and treatment

Pityriasis lichenoides (PL) is an uncommon, acquired spectrum of skin conditions that poses various challenges to patients as well as clinicians. It is a difficult and debatable disorder to diagnose, categorize, and treat. Besides these inherent obstacles, PL merits awareness because of its potential to progress to cutaneous lymphoma or an ulceronecrotic presentation, both of which carry a significant risk of mortality. The scope of PL presentations is delineated along a continuum of multiple variants including pityriasis lichenoides et varioliformis acuta (PLEVA), pityriasis lichenoides chronica (PLC), and febrile ulceronecrotic Mucha-Habermann disease (FUMHD). Classification of these presentations as separate subsets is debatable in view of their overlapping clinical, histopathologic, and etiologic features. PLEVA generally presents as an acute-to-subacute skin eruption of multiple, small, red papules that develops into polymorphic lesions and vacillates with periods of varying remissions as well as possible sequelae of hyper/hypopigmentation and varicella-like scars. PLC has a more gradual manifestation of very small red-to-brown flat maculopapules with mica-like scale; it also follows a relapsing course but with long periods of remission. FUMHD is an acute and severe generalized eruption of purpuric and ulceronecrotic plaques with associated systemic involvement and a mortality rate of up to 25%; hence, it should be approached as a dermatologic emergency.Histopathological evaluation of PL usually reveals dermal, wedge-shaped, lymphocytic infiltrate, epidermal spongiosis, parakeratosis, and variable necrosis of keratinocytes. PLC demonstrates more subtle histology whereas, at the other end of the spectrum, febrile ulceronecrotic FUMHD exhibits the most exaggerated histological features. The pathogenic mechanism behind PL is unclear although infectious or drug-related hypersensitivity reactions versus premycotic lymphoproliferative disorder are the mainstay theories. The foremost therapies for PLEVA and PLC are phototherapy, systemic antibacterials, and topical corticosteroids. Aggressive treatment with immunosuppressant and/or immunomodulating agents as well as intensive supportive care are recommended for FUMHD. We first describe a representative case of a 14-year-old boy with PLC who was successfully treated with narrow-band UVB. We then review the pathophysiology, classification, and treatment of PL.

Pityriasis lichenoides chronica: an association with autoimmune hepatitis?

Pityriasis lichenoides is an uncommon, benign skin disorder with two major variants: acute and chronic. Autoimmune hepatitis comprises heterogeneous forms of chronic hepatitis that are generally progressive and often fluctuating. Two major forms of this entity are recognized. Herein, we report the concurrence of pityriasis lichenoides chronica with type I autoimmune hepatitis in a child, which, to the best of our knowledge, has not been previously reported. Although it is hard to say whether an etiologic relationship or coincidental coexistence occurred between the two entities in our patient, some common mechanisms may be involved in both diseases.