Etiopathogenesis of atopic dermatitis--an overview

Atopic eczema/dermatitis syndrome is a term that covers different subtypes of atopic dermatitis. The "intrinsic" type of atopic dermatitis is non-IgE-associated, and the "extrinsic" type is IgE-associated atopic eczema/dermatitis syndrome. In the etiopathogenesis of atopic dermatitis there are well known interactions among genetic, environmental, skin barrier, immune factors, and stress. Genetic factors determine the expression of atopic dermatitis as pure or mixed with concomitant respiratory or intestinal allergy, depending on genetic susceptibility. Immunologic abnormalities of type I and type IV reactions have been described in patients with atopic dermatitis. Immunologic triggers are aeroallergens, food allergens, microbial products, autoallergens and contact allergens. Immune reactions determine many features of atopic dermatitis. These immune reactions also include cell mediated or delayed hypersensitivity. The currently accepted model proposes a predominant Th2 cytokine milieu in the initiating stages of acute atopic dermatitis lesions, and a mixed Th1 and Th2 pattern in chronic lesions. A two-phase model includes Th2 initiation with attraction of macrophages and eosinophils, which in turn produce interleukin 12 that is the activator of Th1 type response. Atopic dermatitis skin contains an increased number of IgE-bearing Langerhans cells which bind allergens via the high-affinity IgE receptor (FcepsilonRI). Langerhans cells play an important role in cutaneous allergen presentation to Th2 cells via major histocompatibility molecules. Eosinophilia and IgE production are influenced by type 2 cytokines. Degranulation of eosinophils occurs in the dermis with the release of toxic proteins such as major basic protein and could account for much of the inflammation. Mast cells are increased in number and produce mediators other than histamine that induce pruritus and may have an effect on interferon gamma expression. Mast cells produce a number of proinflammatory cytokines. There is an elevated production of prostaglandin E2 by peripheral monocytes. Prostaglandin E2 has at least two potential roles in the initiation of atopic dermatitis. Firstly, it reduces interferon-gamma production by T helper cells, thereby favoring the initial, dominant Th2 immune response; and secondly, it directly enhances IgE production by B lymphocytes with an increased secretion of interleukin 4, interleukin 5 and interleukin 13. Many lesions of atopic dermatitis result from scratching, thus it is tempting to speculate that immune perturbations in genetically predisposed individuals provoke the release of local pruritogens and keratinocyte-derived cytokines, which then further exacerbate the previously described immune response.

[Identification of Langerhans cells in dermatology]

This paper describes our own findings on the role of Langerhans' cells in dermatology and discusses literature data on their detection in seven different dermatoses. The skin is an integral part of immune system. During the past 30 years, increasing evidence has been accumulated that the skin contains cellular elements which are needed for the initiation and expression of immune response. Langerhans' cells (LCs) are dendritic cells originating in the bone marrow. They reside mainly within stratified squamous epithelia and constitute approximately 2-4% of epithelial cells. LCs are epidermal antigen presenting cells which play a crucial role in allergic contact hypersensitivity, viral diseases, graft versus host disease and elimination of neo-plastic cell clones. They express antigens conjugated with major histocompatibility complex (MHC) class II positive molecules on their surfaces for presentation to T-helper lymphocytes. LCs cannot be identified in routinely prepared histologic testing but can be visualised at the light microscope level by histochemical and immunologic techniques. Appropriate methods for the detection of Langerhans' cells in dermatology (also shown by our own experience) are histoenzymatic methods of adenosintriphosphatase (ATP-ase), acid phosphatase (AP), alpha-naphthylacetatesterase (ANAE and peroxidase-antiperoxidase immunohistochemistry method with polyclonal S-100 protein antibody (PAP). LCs are the only cells in normal skin with ATP-ase activity. Histoenzymatic methods used in patients with atopic dermatitis, vitiligo, mycosis fungoides, Behcet's disease, lichen ruber planus, psoriasis vulgaris, irritant dermatitis and allergic contact dermatitis demonstrated LSs in epidermis and dermis. ANAE and AP showed concordance and were suitable histochemical markers for LC distribution and macrophages in the dermis in mycosis fungoides, atopic dermatitis, psoriasis vulgaris, irritant chronic dermatitis and Bechet's disease. Our experience of the human skin showed a strong activity of calcium-activated adenosine triphosphatase in LCs. LCs in the guinea pig skin can be demonstrated by Mg++ and Ca++ activated adenosine triphosphatase, but a stronger activity of Ca++ activated adenosine triphosphatase in LCs after irritation. Ca++ ATP-ase as an indicator of energy-dependent pump is the reflection of intracellular calcium level, which is a significant factor for regulating the growth and metabolism of the cells. LCs are found as target cells during the efferent phase of contact allergic reaction. Immunohistochemical methods, define the role of LCs in dermatology more precisely and allow complete immunologic recognition within the epidermis.

Retrospective survey of patch testing at department of dermatology and venerology, zagreb university hospital center in zagreb, croatia

Epicutaneous (patch) test is a standard test to confirm contact allergy. During a six-year period (1998-2003), contact allergic dermatitis was diagnosed in 4132 (65%) of 6341 patients using standard patch test with a Croatian series of allergens according to the International Contact Dermatitis Research Group (ICDRG). The most common clinical diagnoses related to contact allergy (male; female) were contact allergic dermatitis (65.4%; 72.2%); atopic dermatitis (15.9%; 11.7%); contact irritant dermatitis (7.0%; 6.6%) and nummular eczematoid dermatitis (4.2%; 2.4%). According to occupation, positive patch test reaction was most commonly observed in workers, whereas 65% of patients showed positive reactions to one or more substances. There was an increased frequency of positive patch test reactions to potassium dichromate, nickel sulfate, thimerosal and neomycine sulfate, along with a significant decrease in the frequency of positive patch test reactions to cobalt chloride, carba mix, wood tars, detergents, parabens mixture, urushiol and rubber mixture. We strongly recommend keeping up-to-date with the epidemiology of contact allergy in Croatia.

Erythromelalgia

Erythromelalgia is a rare poorly understood clinical condition characterized by intense burning pain, pronounced erythema, and increased skin temperature. Although there are many classifications of the disease, it can basically be divided into primary, which begins spontaneously at any age, and secondary, which is associated with myeloproliferative disorders-related thrombocythemia, polycythemia, collagen-vascular diseases, diabetes mellitus, peripheral neuropathy, autoimmune and infectious diseases, and use of certain medicaments. A wide variety of etiological conditions can cause erythromelalgia, all having a single common pathogenetic mechanism - microvascular arteriovenous shunting. The disease is characterized by severe pain associated with redness and hotness in extremities. The diagnosis is based on the medical history and clinical findings. The most useful oral medications for erythromelalgia seem to be aspirin, propranolol, clonazepam, cyproheptadine, drugs inhibiting serotonin re-uptake (venlafaxine and sertraline), tricyclic antidepressants (amitriptyline, imipramine), anticonvulsants (gabapentin), calcium antagonists (nifedipine, diltiazem), and prostaglandins (micoprostol). Erythromelalgia is usually chronic, sometimes progressive, and disabling disease, which can greatly affect the quality of life. Some patients have stable disease and get better, or even experience full resolution of the disease, with time. This review article presents the etiological basis, diagnostics, and therapy of erythromelalgia.

Nevus comedonicus--case report and review of therapeutical approach

Nevus comedonicus is uncommon abnormality of pilosebaceous unit, clinically characterized as confluent clusters of dilated follicular orifices plugged with pigmented keratinous material that resembles open comedones. It is suggested that nevus comedonicus is an uncommon variant of adnexal hamartoma, which clinically appears as linear group of open comedones. Since Kofmann's description of nevus comedonicus in 1895, there have been reports of this rare cutaneous disorder associated with developmental anomalies. We present a case of a 19-year-old woman with numerous 1-3 mm size darkly pigmented, keratic plugs clustered in linear unilateral patches on left abdominal part. Our treatment consisted of the avoidance of the formulations containing nickel sulfate and carba mixture, daily local application of tretinoin 0.1% gel and corticosteroid ointment (momethasone furoate). After 4 weeks of local therapy cosmetic result was evident. The slight resolution of keratin plugs could also be seen. Two months after the treatment, there were no visible skin exacerbations.

Etiopathogenesis, classification, and current trends in treatment of rosacea

Rosacea is a common chronic dermatosis characterized by varying degrees of flushing, erythema, telangiectasia, edema, papules, pustules, ocular lesions, and phymas. Etiology and pathogenesis of rosacea are still unknown. Many possible causes have been described as inducing the disease or contributing to its manifestation, such as genetic predisposition, abnormal vascular reactivity, changes in vascular mediating mechanisms, Helicobacter pylori infection, Demodex folliculorum infestation, seborrhea, sunlight, hypertension, and psychogenic factors. However, none of these factors has been proved. Rosacea shows a wide spectrum of clinical presentations, which vary over time and with age. Successful management of rosacea requires careful patient evaluation and individualized therapy with appropriate variations and modifications, as the severity of the disorder fluctuates. In mild cases of rosacea, patients are instructed to avoid sun, to apply sun-protective creams, and to avoid facial irritants and other triggers that provoke symptoms. At later stage, drug therapy is often necessary. The disease commonly requires long-term treatment with topical or oral medicaments. Surgical correction may be required for rhinophyma and telangiectasia. We reviewed the current literature on the aspects of the pathogenesis, diagnostic criteria, and treatment options for rosacea.

[Diagnostic approach in vesicular and bullous dermatoses]

Vesicular and bullous dermatoses are etiopathologically different dermatoses, whose basic manifestations are vesicles or bullae. There are hereditary and acquired vesicular and bullous dermatoses. The diagnosis is based on the anamnesis, dermatologic status and laboratory findings, which are presented in detail. The aim of this paper is to show a diagnostic algorithm for vesicular and bullous diseases of the skin and mucous membranes. Correct diagnosis is the precondition an adequate treatment in patients as well as for a better prognosis.

Pemphigus vulgaris: a review of treatment over a 19-year period

BACKGROUND

Pemphigus vulgaris is an autoimmune blistering disease of the skin and mucous membranes with a high mortality if left untreated.

OBJECTIVE

We present a retrospective analysis of 159 patients with pemphigus vulgaris and pemphigus vegetans who were admitted to the Department of Dermatology and Venereology, Zagreb University Hospital Center (Zagreb, Croatia) from 1980 to 1998.

RESULTS

Female to male ratio was approximately 2:1. The mean age was 53 years. During the war years in Croatia (1991-95) we noticed a low incidence of pemphigus vulgaris, and from 1996 to 1998 the incidence almost doubled. Diagnosis was based on histopathology [showing typical pemphigus vulgaris changes in 156 (98%) patients], indirect immunofluorescence [positive in 122 (77%) patients], direct immunofluorescence [positive in 141 (89%) patients], and blister smear cytology (Tzanck test) [positive in 115 (72%) patients]. High dosages of prednisone (100-150 mg) were given to 129 patients, which was combined with azathioprine. Patients with refractory pemphigus vulgaris were treated with intramuscular gold (14 patients) and plasmapheresis (five patients). All patients were treated with local ointments. The prolonged use of high doses of corticosteroids and immunosuppressants caused several complications, in particular, steroid diabetes (37 patients), skin infections (26 patients), arterial hypertension (23 patients), cardiorespiratory diseases (22 patients), sepsis (nine patients), etc. During the hospital treatment, 14 patients died, 10 during 1980-89 and only four during the 1990-98 period. The main causes of death were cardiorespiratory failure (six patients) and sepsis (five patients).

CONCLUSIONS

Although pemphigus vulgaris is still a life-threatening disease, today it can be successfully treated with a combination of immunosuppressive agents. Early diagnosis and treatment of pemphigus vulgaris allow a better prognosis with lower mortality rates.

Tacrolimus ointment: a new therapy for atopic dermatitis--review of the literature

Atopic dermatitis is a chronic inflammatory skin disease characterized by severe pruritus, typical morphology and distribution of skin lesions, and personal and family history of atopy. The management of atopic dermatitis is directed at preventing the inflammation, itch, and secondary lesions. Therapy relies on general management measures, anti-inflammatory agents, antiprurites, antibiotics, and immunosuppressants. Treatment options for patients with severe or longstanding disease, extensive body surface area involvement of facial lesions are limited. Tacrolimus ointment is the first in the class of topical immunomodulators that has been formulated for the treatment of atopic dermatitis in children (2 to 15 years of age) and adult patients. The mechanism of action of tacrolimus in atopic dermatitis seems to involve T-cells, Langerhans cells, mast cells and basophiles. Experimental evidence suggests that tacrolimus inhibits T-lymphocytes activation by binding to an intracellular protein, FKBP-12. This binding phenomenon inhibits the ability of calcineurin to activate the promotor region of the gene for IL-2, IL-3, IL-4, IL-5, interferon gamma, tumor necrosis factor alpha, and granulocyte macrophage colony-stimulating factor, all of which participate in the early immune response and play a role in the pathogenesis of atopic dermatitis. Tacrolimus ointment is not atrophogenic, and is associated with minimal systemic absorption. There were no consistent changes in any laboratory variable during topical tacrolimus therapy. The most common adverse events associated with its use were transient skin burning and pruritus at the site of application. Tacrolimus ointment is safe and efficacious therapy for the treatment of pediatric and adult patients with atopic dermatitis on all skin regions including the face, neck and intertriginous areas. An overview is given of tacrolimus in atopic dermatitis.

Loop excision of the transformation zone (LETZ) as an outpatient method of management for women with cervical intraepithelial neoplasia: our experience

Between March 1996 and July 1998, 90 patients were treated with diathermy loop excision (LETZ) for cytologically, colposcopically and histologically verified cervical intraepithelial neoplasias (CIN), at the outpatient clinic. In average, the patients were 30.22 years of age, and 61.1% of them were nulliparas. In 80 surgical samples (88.9%), the exocervical and endocervical margins were histologically free of disease. From the total of 65 patients with CIN III diagnosis, 58 (89.2%) had free margins samples. In the post-operative period the patients had a changed vaginal discharge for 16 days. A slight feeling of pain in the abdomen lasted for 2.5 days on the average, and most patients did not take analgetics. Moderate postoperative hemorrhage from the excision site occurred in 5 (5.5%) patients, and was outpatiently treated with electrocoagulation, with no need for blood replacement. In 65 patients (90.3%), the cytological control results were normal. During the follow-up period, 9 patients became pregnant, which resulted in 6 terminal deliveries so far; 2 pregnant women are about to deliver, and one is in the first trimester of pregnancy. Cerclage cervicis has not been performed on any of the patients. LETZ is a safe and simple procedure which can be done at outpatient clinics, it is relatively easily mastered, it is short, quite bearable for patients if done only under local analgesia, the equipment costs are acceptable, and the treatment can be used both diagnostically and therapeutically, since an adequate surgical sample is obtained for histological assessment. Cytological and colposcopical check ups are imperative in the postoperative period.