Pruritus is a common symptom associated with many dermatoses, systemic abnormalities, and psychiatric / psychosomatic diseases. Additionally, pruritus is one of the most intractable symptoms due to its complex pathogenesis involving an increasing number of mediators and receptors, undefined neurophysiologic pathways, unclear cerebral processing, and psychophysiology interaction. Clinically, the first challenge of dermatologists is how to get general and interdisciplinary vision of pruritus and to preliminarily figure it out whether there might be underlying systemic or psychosocial disorders. The second challenge is to select efficient individual tailored anti-pruritic treatment, which includes targeted drugs and cognitive-behavioral therapy.

Filaggrin is very important in the terminal differentiation of the skin and the formation of cornified envelope in the stratum corneum. Several mutations in the filaggrin gene have been identified in the last decade, mostly from the European countries. Loss of function mutations in the filaggrin gene results in reduced production of filaggrin, depending on the type and site of mutation. Such mutations in the filaggrin gene have been shown to be the most significant genetic risk factor for development of atopic dermatitis and undoubtedly has a role in the pathogenesis of ichthyosis vulgaris. Though there is theoretical possibility of association with hand eczema and allergic contact dermatitis; in clinical studies, the strength of these associations was not significantly strong. In this review, we have discussed the structure and function of filaggrin, basic genetics, type of mutations in filaggrin gene, and association of such mutations with different dermatoses.

Topical corticosteroids and sunscreens are extensively used formulations, both as over-the-counter products and as prescription medicines. Topical corticosteroids are increasingly being recognized as causes of allergic contact dermatitis. Because of their anti-inflammatory property, contact allergy to these agents may be difficult to suspect and prove. With corticosteroid allergy, there are special issues in patch testing that need to be considered: Screening tests need to be done with budesonide and tixocortol pivalate, and delayed readings are essential to pick up all positive cases. Preventive advice needs to be tailored according to the structural and chemical peculiarities of a particular molecule. Sunscreen allergy is a significant part of cosmetic allergy; especially in cases of photoallergic reactions. Each passing decade is bringing forth new allergens in this class. In many countries, benzophenones have recently been replaced by octocrylene as the leading causes of contact dermatitis to sunscreens. This article provides a broad overview of corticosteroid and sunscreen allergy so that the readers are aware of these important emerging classes of allergens.

Parthenium dermatitis is an immuno-inflammatory disease caused by Parthenium hysterophorus and is the commonest cause of plant dermatitis in India. It is caused by airborne dry and friable plant particles including trichomes, and the most important allergens responsible for allergic contact dermatitis are sesquiterpene lactones. The combined type IV and type I hypersensitivity to parthenium has been recently postulated. In sensitized individuals, it can cause a spectrum of clinical patterns, such as classical airborne pattern, chronic actinic dermatitis-like presentation, mixed pattern dermatitis, exfoliative dermatitis, widespread dermatitis, and other rare patterns. There is definite trend towards change from airborne pattern to chronic actinic pattern in natural history of parthenium dermatitis. Contact sensitivity to parthenium is everlasting, and hence the disease runs a chronic course with exacerbation during summers. Patch testing with acetone or aqueous plant extract is the simplest way of confirming parthenium contact allergy. Management includes avoiding contact with allergen, managing dermatitis with topical corticosteroids/tacrolimus, and other immunosupressives like azathioprine. In future, we expect parthenium dermatitis to become less prevalent due to rapid urbanization and possible development of new biological methods to eradicate the parthenium. Genetic factors associated with susceptibility to parthenium dermatitis need to be studied.

Eczema, the commonest disorders afflicting the hands, is also the commonest occupational skin disease (OSD). In the dermatology outpatient departments, only the severe cases are diagnosed since patients rarely report with early hand dermatitis. Mild forms are picked up only during occupational screening. Hand eczema (HE) can evolve into a chronic condition with persistent disease even after avoiding contact with the incriminated allergen / irritant. The important risk factors for hand eczema are atopy (especially the presence of dermatitis), wet work, and contact allergy. The higher prevalence in women as compared to men in most studies is related to environmental factors and is mainly applicable to younger women in their twenties. Preventive measures play a very important role in therapy as they enable the affected individuals to retain their employment and livelihood. This article reviews established preventive and therapeutic options and newer drugs like alitretinoin in hand eczema with a mention on the etiology and morphology. Identifying the etiological factors is of paramount importance as avoiding or minimizing these factors play an important role in treatment.

Exposure to hair dyes has long been known as a significant risk factor for development of allergic contact dermatitis among the exposed population as these lead to severe eczema of face and upper trunk in the consumer and hand eczema in hair-dressers. Currently, para-phenylenediamine (PPD) is the main ingredient used in permanent hair color products in the market and is the most important allergen. Prevalence of PPD sensitization is high in patients with contact dermatitis across all continents, with hair dye use being the commonest cause. In order to decrease the burden of disease, use of alternative natural dyeing agents among consumers and use of barrier neoprene gloves among hairdressers should be encouraged apart from stringent legislation to reduce the amount of PPD reaching the consumer.

Contact urticaria, is characterized by an urticarial wheal-and-flare reaction at the site of contact by an allergen. Immunological contact urticaria, while less common than non-immunological contact urticaria, has more potentially serious consequences, and therefore, its recognition and treatment is important. Immunological contact urticaria is a type I hypersensitivity reaction. Potential complications include organ system involvement other than skin and even anaphylaxis and death. A vast majority of immunological contact urticaria is work-related. We will discuss the definition of immunological contact urticaria, the mechanism of the contact urticarial reaction, contact urticaria in the occupational setting, and the role of grains in contact urticaria. Testing and treatment are also briefly discussed.

Background: Following a drug eruption, patients and their doctors need to know which drugs can be safely administered for subsequent illnesses. Currently available laboratory tests are unable to answer this question in a clinically meaningful manner. Aims: To describe our use of oral provocation tests to provide a list of safe drugs to patients. Methods: We studied the records of 100 patients who underwent oral provocation testing in our department between 2003 and 2009. All patients were admitted to hospital and drugs were administered under supervision, one drug per day. A dermatologist evaluated all symptoms and signs that developed following drug intake. Results: Sixty nine women and 31 men underwent provocation testing. There were 96 reactions in 61 patients, of which 44 reactions in 34 patients were judged to be true reactions. All reactions could be controlled, with treatment or spontaneously. A list of safe drugs was provided to the patient along with written instructions to avoid any drug(s) that had produced a reaction. Conclusions: Oral provocation tests are safe and effective in providing patients with a list of drugs they can take safely. These tests should preferably be undertaken after admitting the patient to hospital.

Background: There is a need to develop an in vitro skin models which can be used as alternative system for research and testing pharmacological products in place of laboratory animals. Therefore to study the biology and pathophysiology of pigmentation and vitiligo, reliable in vitro skin pigmentation models are required. Aim: In this study, we used primary cultured melanocytes and keratinocytes to prepare the skin co-culture model in control and vitiligo patients. Methods: The skin grafts were taken from control and patients of vitiligo. In vitro co-culture was prepared after culturing primary melanocytes and keratinocytes. Co- cultures were treated with melanogenic stimulators and inhibitors and after that tyrosinase assay, MTT assay and melanin content assay were performed. Results: Melanocytes and keratinocytes were successfully cultured from control and vitiligo patients and after that co-culture models were prepared. After treatment of co-culture model with melanogenic stimulator we found that tyrosinase activity, cell proliferation and melanin content increased whereas after treatment with melanogenic inhibitor, tyrosinase activity, cell proliferation and melanin content decreased. We also found some differences in the control co-culture model and vitiligo co-culture model. Conclusion: We successfully constructed in vitro co-culture pigmentation model for control and vitiligo patients using primary cultured melanocytes and keratinocytes. The use of primary melanocytes and keratinocytes is more appropriate over the use of transformed cells. The only limitation of these models is that these can be used for screening small numbers of compounds.

Background: Ivermectin has opened a new era in the management of scabies as orally effective drug. However, topical route has been little explored for ivermectin. Aims: To compare the efficacy and safety of topical permethrin, oral ivermectin, and topical ivermectin in the treatment of uncomplicated scabies. Methods: This was an open-label, randomized, comparative, parallel clinical trial conducted in 315 patients, randomly allocated to 3 groups. First group received permethrin 5% cream as single application, second group received tablet ivermectin 200 mcg/kg as single dose, and third group received ivermectin 1% lotion as single application. All the patients received anti-histaminic for pruritus. The patients were followed up at intervals of 1, 2, 3, and 4 weeks. If there were no signs of cure, the same intervention was repeated at each follow up. Primary efficacy variable was clinical cure of lesions. Statistical analysis was done by chi square test and one way ANOVA test using SPSS version 12. Results: At the end of first week, cure rate was 74.8% in permethrin group, 30% in oral ivermectin group, and 69.3% in topical ivermectin group (P < 0.05). At the end of second week, cure rate was 99% in permethrin group, 63% in oral ivermectin group, and 100% in topical ivermectin group (P < 0.05). At the end of third week, 100% cure rate was observed in permethrin and topical ivermectin group while 99% in oral ivermectin group (P = 0.367). No serious adverse events were observed. Conclusions: Permethrin and topical ivermectin were equally effective against scabies while oral ivermectin was significantly less effective up to 2 weeks. Topical ivermectin can be used as an alternative to permethrin.

Background: The incidence of psoriatic alopecia in psoriatic patients is underwhelming, given the prevalence of psoriasis in the North American population. Recently, a 60-year-old Albanian female, lacking a significant medical history for psoriasis, presented to our clinic with a 1-year history of "dandruff" associated with itch, hair thinning, and histopathologic evidence consistent with prior reports of "psoriatic alopecia." Aims: The absence of preceding or concomitant psoriasis suggests that the patient's alopecia is an antecedent manifestation of psoriasis, thus prompting this retrospective study to ascertain better the relationship between alopecia and psoriasis. Methods: We performed a retrospective review of 33 scalp biopsies on 31 patients having histopathologic diagnosis of psoriasis belonging to 31 patients seen between 2007 and 2010. Results: Alopecia was a presenting feature in 48% of cases with definitive clinical and/or histopathologic diagnosis of psoriasis (scale crust with neutrophils, psoriasiform epidermal hyperplasia, and hypogranulosis). The most common follicular-related changes were infundibular dilatation (87%) followed by perifollicular fibrosis (77%), perifollicular lymphocytic inflammation (68%), thinning of the follicular infundibulum (55%), and fibrous tracts (28%). Of interest, sebaceous glands were absent in 60% and atrophic in 25% of cases. Conclusion: While a major limitation of this study is that it is a retrospective one, given that these changes are common to varying degrees in all lymphocytic scarring alopecias, we posit that psoriatic alopecia likely represents a secondary clinical change to a primary process and is not a unique histopathologic entity. A prospective study with a control group that includes lymphocytic scarring alopecias from non-psoriatic patients is required to support our findings.

Background: Onychomycosis is one of the most common nail disorders. Mycological examination by potassium hydroxide (KOH) mount and fungal culture is the most commonly used diagnostic method. However, it is associated with a low sensitivity. Aims: To evaluate the technique of subungual hyperkeratosis nail biopsy in diagnosing onychomycosis in HIV-infected and immunocompetent adults and compare it with mycological examination. Methods: 34 HIV-positive patients who presented clinically with onychomycosis were recruited in the study from the beginning. There was no screening done for patients with onychomycosis. This has been clarified in manuscript under the heading of methods. Results: All the fungal cultures yielded dermatophytes correlating with the biopsy findings. Only hyphal form of fungus was detected in KOH examination, indicating it was not a contaminant. Clinical types of onychomycosis are stated in discussion. Conclusions: PAS stain of subungual hyperkeratosis nail biopsy was the most sensitive in the diagnosis of onychomycosis in both HIV-infected and non-infected groups.

Peeling skin syndrome (PSS) is a rare recessively inherited ichthyosiform genodermatoses characterized by superficial skin peeling. This has 2 subtypes, acral (APSS; OMIM 609796) and generalized form (OMIM 270300). The later has been subdivided into type A (non-inflammatory) and type B (inflammatory). Eight cases of peeling skin syndrome in 4 families were recorded over a period of 5 years. They were diagnosed clinically and confirmed histopathologically. Disease onset ranged from birth to childhood age (mean 5.25 ± 4.528 years) and age at presentation ranged from 7-35 years (mean 23.25 ± 10.471 years). Males outnumbered females (M:F - 5:3). All had non-inflammatory generalized disease of type-A PSS variety, except one who had type-B PSS. Two Muslim families (1 ^st and 2 ^nd family, total 5 patients) came from nearby country Bangladesh, and the 2 Hindu families were Indian. Higher severity over acral areas in generalized type, possible autosomal dominant pattern of inheritance and improvement with age as found in this series were new manifestations and possibly unreported previously. The disease was found to be poorly responsive to oral retinoids. Prevalence of the disease may be higher than expected. Importance of mutational analysis was also highlighted.

Pemphigus is a potentially fatal autoimmune epidermal bullous disorder. Rituximab is a novel therapy for the treatment of refractory pemphigus. However, there is limited clinical data on safety and efficacy of rituximab in pediatric age group. Herein, we report an 11-year-old boy of childhood pemphigus vulgaris who failed to respond to dexamethasone pulse therapy and was subsequently treated with rituximab and achieved complete remission.

Background: Cutaneous adverse drug reactions (CADRs) may either be immunological or non-immunological. The precise mechanisms, however, are largely obscure. Other concomitant mechanisms may amplify and/or contribute to the severity and duration of a reaction. One such mechanism could be oxidative stress, a state of imbalance between reactive oxygen species, and their subsequent detoxification by antioxidants. Aims: (a) to assess the oxidative stress status in the blood of cutaneous drug reaction patients by assaying for reduced glutathione (GSH) and malondialdehyde (MDA) levels, (b) to determine the leukocyte migration inhibition (LMI) response in these patients in response to the suspected drug (s), and (c) to look for the association between oxidative stress parameters and LMI. Methods: Ethical committee approval was obtained for this study. Fresh venous blood samples were obtained from the patients of CADRs (group A) during the acute phase of reaction and healthy control subjects (group B). MDA levels, a measure of oxidative lipid damage, and reduced GSH levels, a measure of anti-oxidant capacity, were assayed in the blood samples of both groups using spectrophotometry. LMI response was measured by challenging the patients' peripheral blood mononuclear cells with the suspected drug to confirm immunological perturbation. Results: Totally 66 participants, 33 cases in group A and equal number of controls in group B, were studied. The mean MDA levels were found to be raised (P < 0.001), but GSH levels were significantly reduced in group A when compared with group B (P = <0.001). LMI response against drug(s) was performed in 33 cases (group A), out of which 25 cases showed a positive LMI response as follows: fixed drug eruption (10/25), SJS (5/25), urticaria (3/25), exfoliative dermatitis (2/25), morbilliform rash (2/25), erythroderma (1/25), vasculitis (1/25), and dapsone syndrome (1/25). The mean MDA levels were found to be significantly higher in the LMI positive CADRs (P < 0.001) when compared with LMI-negative ones, while no significant difference was seen for GSH (P = 0.100). Furthermore, there was a significant positive correlation between MDA levels and LMI response (r = 0.831, P < 0.001). On the other hand, a negative but statistically insignificant correlation was found between GSH and LMI response (r = -0.248, P = 0.271). Conclusion: CADR patients were found to be under oxidative stress based on MDA and GSH levels in the peripheral blood. There is a significant positive correlation of LMI response (against the causative drug) with MDA levels, which strongly associates oxidative stress with the immunopathogenesis in CADRs.