Thalidomide: An option for the pediatric patient with actinic prurigo

Actinic prurigo (AP) is an immune-mediated photodermatosis that usually starts in childhood and is predominant among American indigenous and mestizo communities. In adults with AP, thalidomide is the treatment of choice; however, there is little information on its use in pediatric patients. We report the case of a 10-year-old girl with AP treated successfully with thalidomide.     

Diagnosis and treatment of actinic prurigo

Actinic prurigo (AP) is an idiopathic photodermatosis that affects mainly the mestizo population in Latin America. It has an early onset, a slight predominance in women, and affects the sun-exposed areas of the skin, causing erythematous papules and lichenified plaques secondary to intense and chronic pruritus. Lesions can be induced by both ultraviolet A (UVA) and ultraviolet B (UVB). An association with several human leukocyte antigen (HLA) alleles has been reported. AP is unique among all photodermatoses in its remarkable response to thalidomide. In the past the microscopic features of AP have been considered as nonspecific; however, the constant finding of dense lymphocytic inflammatory infiltrates and the immunogenetic features of AP support the existence of an immunologic mechanism in its pathogenesis.     

Efficacy of dupilumab in prurigo nodularis in elderly patient

Prurigo nodularis (PN) is a chronic disorder, affecting adults, with multiple nodules, typically on the limbs. The treatment is challenging, especially in elderly patients. An 85‐year‐old woman had developed in the last 3 years itch with nodular lesions and erythematous scaly patches and excoriations. The extension of the lesions was evaluated by body surface area (BSA) score and the patient's itch and disease‐related sleep disorders by a Numeric Rating Scale (NRS) from 0 to 10. The Dermatology Life Quality Index (DLQI) and blood chemistry were performed before and during the therapy. At the baseline, the BSA score was 56%. Itch and disease‐related sleep disorders were, respectively, NRS 10 and 5 and DLQI was 9. Total IgE count and lactate dehydrogenase were increased. After starting dupilumab, there was a rapid improvement, especially in pruritus. The patient reported the maximum peak of pruritus every day for 6 months. At this time, the itch almost disappeared and clinically only postinflammatory lesions appreciated, with normalization of the blood tests and without any side effects.     

What is actinic prurigo in Britain?

Actinic prurigo (AP) belongs to the group of idiopathic photodermatoses sharing a predilection for occurring more commonly in females, and there is much controversy as to whether it is only a more severe form of polymorphous light eruption (PMLE) or whether it is a distinct entity in its own right. The condition is characterised by intensely itchy papules, plaques and nodules, along with excoriations and scars usually starting before puberty, and predominantly involves the sun-exposed areas although it may also affect covered sites. Seasonal exacerbations at the beginning of spring with improvement in the fall are typical, although the lesions frequently do not clear completely in the winter. The disorder may run a chronic course and persist into adulthood, but often spontaneous resolution occurs in late adolescence. Diagnosis is predominantly based on the clinical features, cutaneous irradiation tests and histology often being normal or non-specific. HLA typing has also been performed in both PMLE and AP patients, showing a strong association between HLA-DR4, in particular with the DRB1*0407 subtype, and AP; no HLA association has been found in PMLE. This HLA association is likely to be of pathogenic significance and strongly suggests a critical role for MHC-restricted antigen presentation in the development of photosensitivity AP.     

A case of actinic prurigo in Thailand

Actinic prurigo is a separate entity from the polymorphous light eruption that affects American Indians. It has been reported mainly from North and South America, with only few reported cases from Britain or Asia. We report a case of actinic prurigo in a Thai girl who showed cheilitis and pruritic papules on exposed areas for three years. We were able to induce populovesicular lesions by three consecutive irradiations with 100 J/cm2 UVA and 2 minimal erythematous dose of UVB. However, three weeks after irradiation, a prurigo papule developed at the UVB irradiated site.     

Adult-onset actinic prurigo in Thailand

BACKGROUND: Actinic prurigo (AP) is one of the rare idiopathic photodermatosis. It is said to be a familial disease and is usually seen in certain specific geographical areas. The adult-onset type of AP is reported less frequently in the Asian population and has never been reported in Thailand. METHODS: The study population comprised 30 patients. Demographic data were collected. Photo-tests and photo provocation tests for UVA, UVB and visible light were carried out on non-exposed skin. The other investigations included antinuclear antibody, anti-HIV antibody and urine porphyrin level. Histopathology studies were also carried out. RESULTS: There were 18 males and 12 females. The mean age of onset was 36.86 years. The duration of disease was from 1 month to 20 years. Forearms (27 patients) were the most frequently affected site. Other screening tests showed negative results. Five patients had abnormal MED to UVA and one patient had abnormal MED to UVA as well as UVB. Photo provocation tests showed positive responses to both UVA and UVB in 12 cases (40%), a positive response to UVA in 11 cases (37%), a positive response to UVB alone in four cases (13.3%) and a normal response in three patients (10%). None of the patients had a positive response to visible light. Skin biopsies were performed on nodular lesions in 23 cases. Histopathology from these 23 cases showed hyperkeratosis ortho- or parakeratosis and acanthosis in 20 of the 23 cases. CONCLUSIONS: Adult-onset AP in our country may have different geographic and racial distribution from previous reports or may be the tropical variant as described by Tham et al. It may not be an uncommon disease in our country, if there is increased awareness of this disease. Only 16.6% of patients had reduced MED. Photo provocation tests were positive in 90% of cases. Most of the positive wavelengths were UVA or both UVA and UVB. Therefore, photo provocation tests should be performed in cases suspected of AP. The prognosis for AP is not good, despite combinations of treatment. The disorder may run a chronic course. This may be because of our sunny climate and the sun-exposed occupations of patients.     

Dupilumab for pediatric prurigo nodularis: A case report

Herein we report on a 9‐year‐old girl with recalcitrant prurigo nodularis unresponsive to multiple standard treatments. She was started on dupilumab therapy with rapid improvement in pruritus within 2 weeks and near complete regression of lesions at 3 months. Dupilumab should be considered as an off‐label treatment for refractory prurigo nodularis in children.     

A case of actinic prurigo showing hypersensitivity of skin fibroblasts to ultraviolet A (UVA)

We here report a patient with actinic prurigo. He had had erythematous papulovesicular eruptions on the sun-exposed sites from fall to early summer for 4 years. The lesions healed leaving atrophic scars. The histology showed epidermal necrosis and dermal dense perivascular lymphohistiocytic infiltration and edema. His minimal erythema doses to ultraviolet B (UVB) and UVA were normal and lowered, respectively. Skin lesions were produced by repeated irradiation with UVA plus UVB, but not with UVA alone. Then he was diagnosed as having actinic prurigo. Skin fibroblasts from the patient were hypersensitive to UVA. We believe that the hypersensitivity relates to the pathomechanisms of the photosensitivity in the case. UVA sensitivity of fibroblasts may be useful for differentiating actinic prurigo, hydroa vacciniforme, and other similar photosensitive disorders.     

Primary cutaneous B-cell lymphoma associated with actinic prurigo

We describe two patients with a diagnosis of actinic prurigo who subsequently developed cutaneous B-cell lymphoma. This is the first report, to our knowledge, of this association. We propose that chronic antigenic stimulation by ultraviolet radiation, in the context of actinic prurigo, may have been causal in the development of these unusual lymphomas.     

Patch testing in actinic prurigo

42 out of 93 Saskatchewan Indians (32 female (F) and 10 male (M] with actinic prurigo were patch tested to standard series allergens between 1983 and 1987. Positive reactions were most frequently seen with nickel (3F:2M) and colophony. All 3 positive patch tests to colophony were in males. The same patients were also patch tested to extracts of 21 Saskatchewan plants and 3 Hollister-Stier plant extracts. Only 1 male and 2 females had positive patch tests. None of these 3 had rashes on the eyelids, behind the ears or under the chin. We conclude that plant contact dermatitis is unlikely to be mistaken for actinic prurigo in Saskatchewan.     

Disseminated superficial actinic porokeratosis with both typical and prurigo nodularis-like lesions

We report a 50-year-old Korean patient who developed a disseminated superficial actinic porokeratosis (DSAP) with two types of lesions. One was a typical DSAP lesion clinically and histopathologically. The other was clinically similar to prurigo nodularis, but histologic examination showed the findings of porokeratosis such as cornoid lamellae and loss of the granular layer in addition to those of chronic lichenified dermatitis, so it could be described as prurigo nodularis-like porokeratosis. The nodular lesions seemed to develop on preexisting typical lesions of DSAP mainly during the summer by the aggravation of pruritic symptoms and scratching associated with sun exposure. Although we could not find any published reports describing lesions like those of our case, we think that such prurigo nodularis-like porokeratosis can develop in patients with DSAP in some situations involving pruritus and scratching.     

Association of HLA subtype DRB10407 in Colombian patients with actinic prurigo

BACKGROUND: Human leukocyte antigen (HLA) DRB1*0407 had been associated with actinic prurigo in different populations. This class II HLA-DR subtype had not been studied in Colombia. OBJECTIVE: The objective of this study was to establish whether there was an association of actinic prurigo with HLA DR in a Colombian population. MATERIALS AND METHODS: Forty patients with a clinical diagnosis of actinic prurigo and 40 healthy subjects, paired by age, sex and birthplace, were studied. HLA typing for HLA DRB1 and DRB1*04, if necessary, was performed by the PCR-SSP method using blood samples. RESULTS: A high frequency of HLA DRB1*0407 was found in the patients (97.5% vs. 30%; P<0.00001). The allelic frequency of HLA DRB1*0407 was 63.8% in the case group, and 14.5% in the controls (P<0.00001). In the control group, there was a higher frequency of the alleles DRB1*01 (14.5% vs. 1.25%; P=0.0027) and DRB1*13 (23.7% vs. 2.5%; P=0.00013). LIMITATIONS: The small number of controls does not allow us to drive conclusions about other HLA alleles. CONCLUSIONS: HLA subtype DRB1*0407, found in actinic prurigo patients in studies conducted in England, Scotland, Ireland and Mexico, was also associated in Colombian patients. This finding, concordant in patients from different ethnic groups, could be helpful in the diagnosis of this disease and probably important in its pathogenesis. DRB1*01 and DRB1*13 alleles were more frequent in controls than in patients; we do not know whether they play any role in the resistance to the disease.     

Chronic actinic dermatitis treated with mycophenolate mofetil

Chronic actinic dermatitis (CAD) is a persistent photodermatosis that usually affects elderly men. We report two male patients, aged 55 years (patient A) and 49 years (patient B), who presented with an eczematous eruption on sun-exposed skin. Phototesting revealed a markedly reduced 24-h minimal erythema dose (MED). Both patients had refractory disease and developed significant side-effects to conventional therapies, including topical steroids, prednisolone, psoralen with ultraviolet A, azathioprine and ciclosporin. They had each received at least 6 years of treatment prior to commencing mycophenolate mofetil (MMF). Each noted a significant improvement in symptoms within 6 weeks and subsequent clearing of the eczematous lesions. Patient A still requires continuous treatment with MMF 500 mg twice daily to prevent relapses. Patient B maintains remission by using MMF 1 g twice daily only during the spring and summer months. Both patients have tolerated the treatment well with no abnormalities in blood cell counts or liver biochemistry. Since commencing MMF, their quality of life has significantly improved. These observations suggests that MMF should be considered as an alternative treatment to conventional therapies for refractory CAD.     

A case of severe actinic prurigo successfully treated with thalidomide

Actinic prurigo is an uncommon and usually persistent idiopathic photodermatosis with typical human leukocyte antigen (HLA) associations (HLA-DR4, particularly subtypes DRB1*0407 and DRB1*0401). Although its mechanism of action is not clearly understood, thalidomide has been shown to be particularly efficacious in treating actinic prurigo, among other conditions. A 31-year-old Australian woman who had suffered actinic prurigo for most of her life was treated with two courses of thalidomide (50-100 mg nocte) over consecutive summers. Remission was observed after cessation of the second course of thalidomide and had continued 4 years later. Abnormalities in the cutaneous response to ultraviolet radiation at the time of diagnosis, detected by monochromator phototesting, reverted to normal following treatment.     

Effectiveness of dupilumab in pediatric patients with a nummular phenotype of atopic dermatitis

The nummular phenotype of atopic dermatitis is clinically characterized by pruritic, coin-shaped plaques that are frequently recalcitrant to treatment. In this study, a retrospective chart review was conducted to evaluate the effectiveness and safety of dupilumab in children with nummular lesions of dermatitis. Twelve out of 14 patients demonstrated significant clinical improvement at a median time of 2.5 months (interquartile range, 1–4) after dupilumab initiation. A single case of paradoxical psoriasiform eruption was the only side effect reported in our cohort.     

Dupilumab for prurigo nodularis: Case series and review of the literature

Dupilumab is a recombinant complete human monoclonal antibody modulating the signaling of interleukin‐4 and interleukin‐13 pathways and has been approved for the treatment of moderate/severe atopic dermatitis. Here, we present three cases of prurigo nodularis treated off‐label with dupilumab, and a review of the existing literature. All patients in this study had longstanding severe disease and had tried multiple treatment modalities. They were treated with dupilumab at an initial dose of 600 mg subcutaneously, followed by 300 mg every 2 weeks. Systematic literature searches were performed to identify literature describing the evaluation of the effect of treatment with dupilumab in prurigo nodularis. The physician's assessment of the patients revealed a good or excellent response to the treatment with dupilumab. Patients were evaluated after treatment for 4 and 7 months. Treatment was generally well‐tolerated; one in three patients reported dry eyes. Four studies with a total of 11 patients (range: 1–4) were identified by the literature search. Complete response was noted in all 11 patients. Treatment with dupilumab appears to be safe and well‐tolerated with clinical benefit in recalcitrant prurigo nodularis. Larger randomized and controlled trials using validated outcome measures are needed before dupilumab could be applied in clinical settings.     

The spontaneous resolution of photosensitivity and contact allergy in a patient with chronic actinic dermatitis

Chronic actinic dermatitis (CAD) is an uncommon photodermatosis in which patients typically exhibit photosensitivity together with contact allergy. Improvement of the photosensitivity over time is well recognized in a proportion of patients but the concurrent resolution of contact allergy is rare. We report on a 46-year-old female with longstanding CAD who demonstrated resolution of both of these features.