Prevalence of scratching during examination among patients with scabies and among patients with other pruritic dermatoses.

BACKGROUND: Scabies is a parasitic skin disease. Its clinical diagnosis may be challenging. METHODS: In a prospective observational study, we enrolled all consecutive patients ≥16 years of age with a presumptive diagnosis of scabies and all patients ≥16 years of age with a diffuse itchy dermatosis lasting for more than 1 week. We investigated whether patients with scabies were more prone to scratch themselves during the consultation than patients with other pruritic dermatoses. RESULTS: We observed that a significant proportion of patients (25/62, 40%) with scabies had to scratch while talking or being examined. This clinical sign was less frequently noticed in patients with pruritic dermatoses of other origins (26/196, 13%) (P < 0.001). CONCLUSIONS: The observation of a patient scratching himself during the consultation should prompt serious consideration of scabies. This easily observable clinical sign may be especially useful in low-resource settings, where scabies is known to be very prevalent.

Visible light photopatch testing of common photocontactants in female filipino adults with and without melasma: a cross-sectional study.

BACKGROUND: Although consistently associated with sun exposure, melasma is common among sun-shy Filipino women who generally prefer to have lighter skin, use skin lighteners, regularly practice sun avoidance, and are more exposed to indoor lights. OBJECTIVE: To determine presence/absence of photocontact dermatitis in melasma/no-melasma patients using photopatch testing (PhPT) with standard photocontactants and an indoor visible light (VL) source. DESIGN: Cross-sectional study: random population of 40 female patients aged 30-55 years, 20 with and 20 without melasma. The PhPT included 67 photocontactant allergens: 59 from Chemotechnique Diagnostics (24 fragrance, 22 North American photopatch, 13 plants) and 8 cosmetic allergens from Skin Sciences Laboratory Inc. (Pasig, Philippines) in sets of paired test patches. One of the pairs was irradiated with a 500-watt tungsten halogen lamp as the VL source; the other was the nonirradiated control. The standard protocols of the North American Contact Dermatitis Group (NACDG) was used to examine the nonirradiated control patches after 48 and 72 hours, the DAPT (German/ Austrian/ Swiss Photopatch Study Group) was used to examine the VL-irradiated patches, and both protocols were used to interpret relevance of the readings as to the presence or absence of contact dermatitis (CD) or photocontact dermatitis (PhCD). RESULTS: Fifty-five percent of patients in the melasma group (N = 11/20) had 29 positive (+) PhPT reactions to VL-irradiated allergens (11 fragrances, 11 North American, 7 plants). In the no-melasma group, none had (+) PhPT. This association is highly significant (P = 0.00 using 2-tailed Fischer's exact test), such that compared to a (-) PhPT, a (+) PhPT has 12.67 times more likelihood to develop melasma (P = 0.05: 1.402-114). All 29 (+) PhPT were decrescendo type, replaced by pigmentation observed up to 7 days suggesting phototoxic reactions, and all had (+) clinical relevance establishing phototoxic low-energy VL-PhCD. CONCLUSION: Melasma worsens with sun exposure, but this study shows that the low energy of artificial indoor VL is enough to react with photocontactants followed by a pigmentation response that may account for its clinical appearance as a mostly noninflammatory slowly evolving facial pigmentation.

[What's new in clinical dermatology]. / Quoi de neuf en dermatologie clinique?

This selection reviews several topics in the news: - in internal medicine, the cardiovascular and pulmonary risk factors in progressive systemic sclerosis (circulating lupus anticoagulant, smoking, NT-pro BNP marker); the relations between lupus erythematous and polymorphic light eruption, or Jessner-Kanof syndrome; the diagnostic score of autoinflammatory syndromes; and the dysmetabolism syndrome of psoriasis; - in infectious diseases, the return of epidemic typhus; the emergence of TIBOLA rickettsiosis; the development of methicillin-resistant Staphylococcus aureus strains in both the nosocomial and community settings; and finally news on herpes group viral infections.

The effect of solar-simulated radiation on the elicitation phase of contact hypersensitivity does not differ between controls and patients with polymorphic light eruption.

It has been suggested that polymorphic light eruption (PLE) is characterized by a failure of ultraviolet radiation (UVR)-induced immunosuppression, resulting in a type-IV hypersensitivity response to photoinduced antigens. We measured the effect of solar-simulated radiation (SSR) on the elicitation phase of contact hypersensitivity to 2,4-dinitrochlorobenzene (DNCB), in ten PLE patients and 11 controls. Subjects were given a sensitizing dose of DNCB, and 3 wk later were exposed to 0.75 and 2 minimum erythema doses (MED) of SSR on the upper inner arm. Immediately and 24 h later these sites, and a non-irradiated control site, were challenged with DNCB. The resulting increase in skin thickness was measured with high-frequency ultrasound. Overall, 2 MED caused 17%-20% suppression of elicitation responses (compared with 93% suppression of sensitization reported previously), but the effect of SSR varied greatly between subjects, with some subjects showing potentiated responses, which may be of relevance to false-positive reactions in photopatch testing. In a repeated measures general linear model, SSR overall caused significant suppression of responses (p<0.001); there was less suppression in older subjects (p=0.009) but there was no significant difference between PLE patients and age-matched normal controls. These results contrast with our previous finding of a resistance to UVR-induced suppression of sensitization to DNCB in PLE. This difference may reflect the greater importance of Langerhans cells in the sensitization phase, and is consistent with the hypothesis that PLE arises from impaired suppression of Langerhans cell activation or migration.

[Follicular mucinosis secondary to captopril-induced photoallergy]. / Mucinosis folicular secundaria a fotoalergia por captopril.

Captopril is an angiotensin-converting enzyme inhibitor which has been widely used as an antihypertensive agent and vasodilator. Although adverse skin effects occur in 10 % of patients prescribed this drug, there is little published data about photosensitivity. On the other hand, follicular mucinosis has been described in association with numerous processes, mainly lymphomas, lupus erythematosus and, less frequently, with photoinduced eruptions and drug reactions. We present the case of a female patient treated with captopril who developed an eruption in photoexposed areas. Histologically, the patient showed changes consistent with follicular mucinosis, with a positive captopril photopatch test and with resolution of the lesions after the antihypertensive agent was withdrawn.

[Gastric cancer associated with dermatomyositis accompanied by photoallergy].

A 62-year-old man was admitted to the hospital because of a 5-month history of edematous erythema and itching on the face, upper chest, and upper extremities. The symptoms developed immediately after bathing in the sea. Dermatomyositis associated with photoallergy was diagnosed by skin and muscle biopsy. A search for malignancy revealed Borrmann 3 gastric cancer, and subtotal gastrectomy was performed. He has done well for 3 years and 8 months after the operation, but there has been no remission in the symptoms of dermatomyositis. Dermatomyositis associated with photoallergy has a higher incidence of complications with malignant disease than ordinary dermatomyositis.

Dermatite solar felina associada a carcinoma epidermóide / Felinesolar dermatites associated to squamous cell carcinoma

A pele é um dos maiores sistemas do organismo animal, desempenhando importantes papéis e apresenta inúmeras alteraçöes que, frequentemente, levam os proprietários de animais domésticos a procurar os serviços veterinários. A dermatite solar felina é uma doença de natureza ambiental, que acomete gatos brancos ou aqueles que possuem áreas despigmentadas, principalmente nas orelhas e nariz. Esta doença, causada pela exposiçäo da pele despigmentada à radiaçäo ultravioleta, pode evoluir para carcinoma epidermóide nos casos de exposiçäo por período prolongado. A lesäo inicia-se com severo eritema da orelha, progredindo para descamaçäo cutânea e formaçäo de crostas marginais. O controle objetiva evitar o contato da pele despigmentada com a luz solar, principalmente nas horas mais quentes do dia. Para se atingir este objetivo, deve-se evitar que os animais entrem em contato com o sol, mantendo-os presos em horários estratégicos, utilizando filtros solares à base de creme ou ainda confeccionando tatuagens nas áreas despigmentadas. Após a instalaçäo do carcinoma epidermóide, diferentes métodos terapêuticos säo recomendados para o tratamento, dentre eles a cirurgia, com remoçäo total dos tecidos atingidos pela neoplasia, a radioterapia, a fotoquimioterapia, a hipertemia e a terapia com glicocorticóides.

Disease associations in polymorphous light eruption. A long-term follow-up study of 94 patients.

OBJECTIVES: To examine the long-term outcome of polymorphous light eruption (PLE) in a large patient population and to evaluate associated conditions, especially lupus erythematosus, during the course of the disease. DESIGN: A questionnaire-based follow-up study an average of 32 years after onset of PLE. The study was complemented by clinical examination of the patients with PLE similarly studied 16 years earlier or now reporting equal or worse PLE symptoms compared with the 1978-1979 follow-up or any symptoms suggesting an autoimmune disease. SETTING: A dermatologic clinic in a university hospital. PATIENTS: Ninety-four of the original cohort of 138 patients with PLE (87% of living patients) returned the questionnaire, and 46 (84%) of the 55 patients invited volunteered for clinical examination. INTERVENTION: None. MAIN OUTCOME MEASURES: Clinical characteristics of PLE and clinical laboratory findings referring to associated diseases, especially lupus erythematosus. RESULTS: Twenty-three (24%; 95% confidence interval [CI], 16%-34%) of the 94 patients were cured, 48 (51%; 95% CI, 41%-62%) experienced milder symptoms, and 23 (24%; 95% CI, 16%-34%) experienced equal or worse symptoms than in the 1978-1979 follow-up. At least 1 autoimmune disease was diagnosed at some point in 14 patients (15%; 95% CI, 12%-29%) (in 13 [18%] of the female patients) and lupus erythematosus specifically in 2 (2%; 95% CI, 0%-7%) (in 2 [3] of the female patients). The prevalence of a thyroid disease was 14% (13 patients) (95% CI, 8%-23%). CONCLUSION: Polymorphous light eruption is a long-standing slowly ameliorating disease with some tendency to development of autoimmune disease or thyroid disorder, especially in female patients, but the risk for lupus erythematosus is not increased.

Clinical manifestations of photosensitivity in patients with human immunodeficiency virus infection.

A number of light-induced pathologic changes in the skin of individuals with HIV infection have been reported in the dermatologic literature. The relationship between HIV and one of these more well-defined types of photosensitivity, PCT, while still uncertain seems definable and related to an infectious origin. The relationship of retrovirus infection and photosensitivities that are of idiopathic origin in HIV-infected individuals, as well as non-infected individuals, is much more conjectural. The association seems, however, to be more frequent than co-incidental, and the link probably resides in the realm of altered immune modulation. Since individuals with HIV frequently require phototherapy, such light-induced problems are likely to become more common. It is important that the dermatologist recognize these relationships.

Contact allergy to sunscreen chemicals in photosensitivity dermatitis/actinic reticuloid syndrome (PD/AR) and polymorphic light eruption (PLE).

From 1989-1991, 214 patients (45 PD/AR, 54 PLE, 115 controls) were patch tested to a sunscreen series containing 9 constituents. 16/214 (7.5%) patients reacted to one or more sunscreens, with allergy being significantly more common in PD/AR patients (10/45 versus 2/54 PLE and 4/115 contact dermatitis clinic controls). The benzophenone group of sunscreens (mexenone, oxybenzone) were the most frequent sensitizers, accounting for 8 of the 27 positive patch tests observed. Clinicians should consider contact allergy to sunscreens in PD/AR patients as an explanation for exposed-site dermatitis episodes.