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Background Phytophotodermatitis (PPD) is a cutaneous phototoxic inflammatory eruption resulting from contact with light-sensitizing botanical substances and long-wave ultraviolet (UV-A 320-380 nm) radiation. The eruption usually begins approximately 24 hours after exposure and peaks at 48-72 hours. [1] Phytophotodermatitis typically manifests as a burning erythema that may subsequently blister. Postinflammatory hyperpigmentation lasting weeks to months may ensue. In some patients, the preceding inflammatory reaction may be mild and go unrecognized by the patient. In this case, the patient presents with only pigmentary changes. Also see Berloque Dermatitis and Drug-Induced Photosensitivity . Pathophysiology Cutaneous inflammation produced by plants can be separated into 4 groups based on their specific mechanism of action: urticarial dermatitis, irritant contact dermatitis , allergic contact dermatitis , and phototoxic dermatitis. Phytophotodermatitis is a phototoxic reaction entirely independent of the immune system; that is, phytophotodermatitis can occur in any individual, and prior sensitization or an intact immune system is not required. The ingredients needed to produce phytophotodermatitis include temporal exposure to both a photosensitizing substance, such as psoralens, and ultraviolet radiation. Furocoumarins are photosensitizing chemical components produced by certain plants and consist of psoralens, 5- methoxypsoralens, 8-methoxypsoralens, angelicin, bergaptol, and xanthotal. The natural sunlight emission spectrum reaching the earth ranges from approximately 270-5000 nm. This electromagnetic radiation consists of photons with a reciprocal relationship between the wavelength and the energy of the photons. Only light that is absorbed into the skin can cause a photochemical reaction. Within the light spectra, UV-A (320-380 nm) is responsible for the vast majority of photoreactions resulting in phytophotodermatitis. The wavelengths of ultraviolet light that most efficiently produce phytophotodermatitis lie within the UV-A range and have peak activity at 335 nm. When a photon with the appropriate wavelength strikes a furocoumarin, the energy is absorbed, raising this chemical to a triple excited state from the ground state. Upon return to the ground state, energy is released in the form of heat, fluorescence, and/or phosphorescence, and a photoproduct may form. Two distinct photochemical reactions have been described in phytophotodermatitis, which occur independently from each other. A type I reaction occurs in the absence of oxygen, whereas a type II reaction occurs in the presence of oxygen. These photochemical reactions damage cell membranes and DNA and result in DNA interstrand cross-linking between the psoralen furan ring and the thymines or the cytosines of DNA. This results in activation of arachidonic acid metabolic pathways and in cell death

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BackgroundPhytophotodermatitis (PPD) is a cutaneous phototoxic inflammatory eruption resulting from contact with light-sensitizing botanical substances and long-wave ultraviolet (UV-A 320-380 nm) radiation. The eruption usually begins approximately 24 hours after exposure and peaks at 48-72 hours.[1]

Phytophotodermatitis typically manifests as a burning erythema that may subsequently blister. Postinflammatory hyperpigmentation lasting weeks to months may ensue. In some patients, the preceding inflammatory reaction may be mild and go unrecognized by the patient. In this case, the patient presents with only pigmentary changes.

Also see Berloque Dermatitis and Drug-Induced Photosensitivity.

PathophysiologyCutaneous inflammation produced by plants can be separated into 4 groups based on their specific mechanism of action: urticarial dermatitis, irritant contact dermatitis, allergic contact dermatitis, and phototoxic dermatitis.

Phytophotodermatitis is a phototoxic reaction entirely independent of the immune system; that is, phytophotodermatitis can occur in any individual, and prior sensitization or an intact immune system is not required. The ingredients needed to produce phytophotodermatitis include temporal exposure to both a photosensitizing substance, such as psoralens, and ultraviolet radiation. Furocoumarins are photosensitizing chemical components produced by certain plants and consist of psoralens, 5-methoxypsoralens, 8-methoxypsoralens, angelicin, bergaptol, and xanthotal.

The natural sunlight emission spectrum reaching the earth ranges from approximately 270-5000 nm. This electromagnetic radiation consists of photons with a reciprocal relationship between the wavelength and the energy of the photons. Only light that is absorbed into the skin can cause a photochemical reaction. Within the light spectra, UV-A (320-380 nm) is responsible for the vast majority of photoreactions resulting in phytophotodermatitis.

The wavelengths of ultraviolet light that most efficiently produce phytophotodermatitis lie within the UV-A range and have peak activity at 335 nm. When a photon with the appropriate wavelength strikes a furocoumarin, the energy is absorbed, raising this chemical to a triple excited state from the ground state. Upon return to the ground state, energy is released in the form of heat, fluorescence, and/or phosphorescence, and a photoproduct may form.

Two distinct photochemical reactions have been described in phytophotodermatitis, which occur independently from each other. A type I reaction occurs in the absence of oxygen, whereas a type II reaction occurs in the presence of oxygen. These photochemical reactions damage cell membranes and DNA and result in DNA interstrand cross-linking between the psoralen furan ring and the thymines or the cytosines of DNA. This results in activation of arachidonic acid metabolic pathways and in cell death (sunburn cells and apoptotic keratinocytes). Clinically, erythema, blistering, epidermal necrosis, and eventual epidermal desquamation occur. See the image below.

Close-up view of vesicular linear streaks with morphology suggestive of scattered foci of epidermal necrosis.A postinflammatory pigment alteration may follow the acute phase of this phototoxic reaction. This alteration occurs primarily by 2 mechanisms. First, melanin, which is normally found in the epidermis, "falls" into the dermis and is ingested by melanophages. Secondly, an increased number of functional melanocytes and melanosomes are distributed in the epidermis following phytophotodermatitis and also account for the hyperpigmentation. This hyperpigmentation may serve as a protective mechanism against further UV injury. Clinically, this corresponds with irregular hyperpigmentation (or

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occasionally hypopigmentation resulting in dyschromia) seen as the end stage of the phototoxic reaction.

EpidemiologyFrequency

United StatesThe frequency of phytophotodermatitis in the general population has not been well established.

InternationalThe overall incidence of phytophotodermatitis is unknown, but it undoubtedly varies according to the population studied and is based on the risk of exposure to psoralen compounds. Because furocoumarins are found in a wide range of wild and domestic plants, a variety of patient groups may become exposed.

Mortality/Morbidity

Most commonly, phytophotodermatitis is a localized cutaneous phenomenon resulting initially in a burning sensation, which may be followed acutely by erythema and blistering. Eventually, the affected sites may desquamate and develop permanent hyperpigmentation or hypopigmentation. However, scarring is rare.

Race

Any race may be affected, but phytophotodermatitis is most easily recognized in fair-skinned patients.

Sex

Both sexes may be affected.

Age

Any age may be affected, but note that phytophotodermatitis occurring on a child may be mistaken for child abuse. Classic examples include a handprint pattern on a child after exposure to a parent cooking with lime juice or a linear drip pattern on a child's hands and arms after eating real juice ice pops.

Physical

The primary skin lesion of phytophotodermatitis may range from delayed erythema (24-48 h) to frank blisters. The skin lesions are limited to the areas in contact with furocoumarin and with sunlight exposure. The primary lesion is often not seen by the physician because of the transient nature of the reaction. Rather, the patient presents with late skin changes that become apparent after 72 hours.

Late skin lesions

Bizarre inflammatory patterns and linear streaks of hyperpigmentation are key clues to diagnosing phytophotodermatitis. These patterns often result from brushing against a plant's stems or leaves while outdoors or from the liquid spread of lime juice over the hand or down the forearm. A handprint pattern from lime juice contact is not uncommon. See the

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images below. A 37-year-old white woman presented to the clinic complaining of a rash on the medial part of her right thigh and left arm that was acquired after clearing some weeds in her yard. A phototoxic combination of sunlight and a psoralen-containing plant produced this bizarre linear vesicular eruption.

Closer clinical view of bizarre angulated vesicular streaks, which occurred after contact with a plant and ultraviolet light exposure.

A 26-year-old female airline flight attendant exposed to lime while serving drinks en route to the Caribbean. During the Caribbean layover, she had significant sun exposure. The combination of lime juice and sun exposure led to a drip-pattern blister formation on the dorsal forearm consistent with phytophotodermatitis. This picture clearly delineates the potential severity of phytophotodermatitis with extensive blister formation.

Furthermore, a buckshot spray over exposed surfaces is commonly seen in association with the use of string trimmers (weed-whackers) when unwanted weeds possessing furocoumarins are cleared from a field or a yard.

Skin distribution: Phytophotodermatitis is most commonly found on skin sites exposed to plants and sunlight; these include such areas as the arms and the legs, but it may occur anywhere.

Skin color: Skin color varies depending on the patient's underlying skin tone and the degree of the reaction. However, as previously stated, the acute phase of phytophotodermatitis manifests as erythema, and the end stage manifests as postinflammatory

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hyperpigmentation, as shown below. The 2-month follow-up picture of a patient with a drip-pattern blister formation on the dorsal forearm demonstrates the potential postinflammatory pigmentation changes and scarring that may occur with severe blistering of phytophotodermatitis.

Background Phytophotodermatitis (PPD) is a cutaneous phototoxic inflammatory eruption resulting from

contact with light-sensitizing botanical substances and long-wave ultraviolet (UV-A 320-380 nm) radiation. The eruption usually begins approximately 24 hours after exposure and peaks at 48-72 hours.[1]

Phytophotodermatitis typically manifests as a burning erythema that may subsequently blister. Postinflammatory hyperpigmentation lasting weeks to months may ensue. In some patients, the preceding inflammatory reaction may be mild and go unrecognized by the patient. In this case, the patient presents with only pigmentary changes.

Also see Berloque Dermatitis and Drug-Induced Photosensitivity. Pathophysiology Cutaneous inflammation produced by plants can be separated into 4 groups based on their

specific mechanism of action: urticarial dermatitis, irritant contact dermatitis, allergic contact dermatitis, and phototoxic dermatitis.

Phytophotodermatitis is a phototoxic reaction entirely independent of the immune system; that is, phytophotodermatitis can occur in any individual, and prior sensitization or an intact immune system is not required. The ingredients needed to produce phytophotodermatitis include temporal exposure to both a photosensitizing substance, such as psoralens, and ultraviolet radiation. Furocoumarins are photosensitizing chemical components produced by certain plants and consist of psoralens, 5-methoxypsoralens, 8-methoxypsoralens, angelicin, bergaptol, and xanthotal.

The natural sunlight emission spectrum reaching the earth ranges from approximately 270-5000 nm. This electromagnetic radiation consists of photons with a reciprocal relationship between the wavelength and the energy of the photons. Only light that is absorbed into the skin can cause a photochemical reaction. Within the light spectra, UV-A (320-380 nm) is responsible for the vast majority of photoreactions resulting in phytophotodermatitis.

The wavelengths of ultraviolet light that most efficiently produce phytophotodermatitis lie within the UV-A range and have peak activity at 335 nm. When a photon with the appropriate wavelength strikes a furocoumarin, the energy is absorbed, raising this chemical to a triple excited state from the ground state. Upon return to the ground state, energy is

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released in the form of heat, fluorescence, and/or phosphorescence, and a photoproduct may form.

Two distinct photochemical reactions have been described in phytophotodermatitis, which occur independently from each other. A type I reaction occurs in the absence of oxygen, whereas a type II reaction occurs in the presence of oxygen. These photochemical reactions damage cell membranes and DNA and result in DNA interstrand cross-linking between the psoralen furan ring and the thymines or the cytosines of DNA. This results in activation of arachidonic acid metabolic pathways and in cell death (sunburn cells and apoptotic keratinocytes). Clinically, erythema, blistering, epidermal necrosis, and eventual epidermal desquamation occur. See the image below.

Close-up view of vesicular linear streaks with morphology suggestive of scattered foci of epidermal necrosis.

A postinflammatory pigment alteration may follow the acute phase of this phototoxic reaction. This alteration occurs primarily by 2 mechanisms. First, melanin, which is normally found in the epidermis, "falls" into the dermis and is ingested by melanophages. Secondly, an increased number of functional melanocytes and melanosomes are distributed in the epidermis following phytophotodermatitis and also account for the hyperpigmentation. This hyperpigmentation may serve as a protective mechanism against further UV injury. Clinically, this corresponds with irregular hyperpigmentation (or occasionally hypopigmentation resulting in dyschromia) seen as the end stage of the phototoxic reaction.

Epidemiology Frequency United States The frequency of phytophotodermatitis in the general population has not been well

established. International The overall incidence of phytophotodermatitis is unknown, but it undoubtedly varies

according to the population studied and is based on the risk of exposure to psoralen compounds. Because furocoumarins are found in a wide range of wild and domestic plants, a variety of patient groups may become exposed.

Mortality/Morbidity Most commonly, phytophotodermatitis is a localized cutaneous phenomenon resulting

initially in a burning sensation, which may be followed acutely by erythema and blistering. Eventually, the affected sites may desquamate and develop permanent hyperpigmentation or hypopigmentation. However, scarring is rare.

Race Any race may be affected, but phytophotodermatitis is most easily recognized in fair-skinned

patients. Sex

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Both sexes may be affected. Age Any age may be affected, but note that phytophotodermatitis occurring on a child may be

mistaken for child abuse. Classic examples include a handprint pattern on a child after exposure to a parent cooking with lime juice or a linear drip pattern on a child's hands and arms after eating real juice ice pops.

Photocontact dermatitisA toxic or allergic reaction may occur when certain chemicals are applied to the skin and subsequently exposed to the sun. This is called photocontact dermatitis.

What causes photocontact dermatitis?

Photocontact dermatitis most often arises from interaction between UV radiation and one or more of the products listed below:

Some sunscreens, e.g. oxybenzone or cinnamates and others

Coal tar products

Fragrances , e.g. musk

Insecticides  and disinfectantsThese products contain drugs or chemicals that are photosensitising agents (see drug-induced photosensitivity).The reaction can be phototoxic and/or photoallergic.

Phototoxic reactions result from direct damage to tissue caused by light activation of the

photosensitising agent

Photoallergic reactions are a cell mediated immune response in which the antigen is the

light-activated photosensitising agent.

Phytophotodermatitis

Another cause of photocontact dermatitis is from the interaction of UV radiation and photosensitising compounds found in various plants. This type of dermatitis is called phytophotodermatitis. The most common plant family to cause phytophotodermatitis is the Umbellliferae family. Other plant families that cause phytophotodermatitis are Rutaceae, Moraceae and Leguninosa. The main photosensitising substances found in these plants are called furocoumarins and consist of psoralens and 5-methoxypsoralens, 8-methoxypsoralens, angelicin, bergaptol and xanthotal.

Plant family Plant/vegetable/fruit with furocoumarins

Umbelliferae Parsnip

Celery

Parsley

Cow parsnip/hogweed

Giant hogweed

Rutaceae Bergamot lime  (Citrus bergamia)

Citron  (Citrus medica)

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Zabon (Citrus maxima)

Moraceae Fig

Leguminosa Beans

What are the clinical features of photocontact dermatitis?

The clinical features of photocontact dermatitis vary according to the photosensitising agent involved and the type of reaction it causes in the skin.

A phototoxic reaction generally appears similar to a bad sunburn.

A photoallergic reaction generally presents as an eczema (also called dermatitis) confined

to the areas in contact with the responsible chemical and exposed to the sun.

Photocontact dermatitis

 

Sunscreen

 

Creasote

Phytophotodermatitis is a result of a phototoxic reaction and has characteristic clinical features. These include:

Blisters and brown streaks occurring from touching certain plants followed by sun

exposure. These patterns result from brushing against a plant's stems or leaves when

outdoors or from lime juice squeezed over the hand or down the forearm.

Blisters or swellings may occur minutes to hours after exposure to the plant and light, but

more usually erupt about 24 hours after exposure, peaking at 48-72 hours.

Skin lesions may leave behind dark marking on the skin (postinflammatory

hyperpigmentation).

Phytophotocontact dermatitis

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What is the treatment for photocontact dermatitis?

The main goal of treatment is to identify the photosensitising agent and if possible to avoid touching it. Photodermatitis is a self-limited problem that resolves spontaneously once the offending agent is removed or avoided.

If avoiding the offending agent is not practical, then affected individuals should follow sun protection strategies, including wearing sun protective clothing and using sunscreen.If allergic to a sunscreen agent, choose one without the responsible chemical or select a low irritant formula that relies on physical methods of reflecting sunlight.

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Modul Kulit Kelamin _ Dermatitis Kontak

Trigger : Seorang laki-laki, petani umur 30 tahun datang dengan keluhan gatal pada kedua punggung kaki kiri dan kanan sejak 1 bulan yang lalu. Pada pemeriksaan terlihat bentuk lesi seperti sandal jepit depan dengan efloresensi polimorfik berupa papula, plak eritem, plak hiperpigmentasi, pustula, erosi ekskoriasi, likenifikasi. Diagnosis mengarah pada Dermatitis Kontak Alergi (DKA).

Learning Objective :

1. Definisi, gejala dermatitis.

2. Semua hal mengenai Dermatitis Kontak (Dermatitis Kontak Alergi/DKA dan Dermatitis Kontak Iritan/DKI)

3. Diagnosis dan diagnosis banding Dermatitis Kontak.

4. Uji tempel (Patch test)

5. Penatalaksanaan dan pencegahan Dermatitis Kontak.

6. Prognosis Dermatitis Kontak.

Add 1. Definisi dan Gejala Dermatitis

Dermatitis adalah peradangan kulit (epidermis dan dermis) sebagai respons terhadap pengaruh faktor eksogen dan endogen, menimbulkan kelainan klinis berupa efloresensi polimorfik (eritema, edema, papul, vesika, skuama, likenifikasi) dan keluhan gatal. Tanda polimorfik tidak selalu timbul bersamaan, bahkan mungkin hanya beberapa (oligomorfik). Dermatitis cenderung residif dan menjadi kronis. Sinonim dermatitis adalah ekzem.

Penyebab dermatitis dapat berasal dari luar (eksogen) misalnya bahan kimia (detergen, asam, basa, oli, semen), fisik (sinar matahari, suhu), mikroorganisme (bakteri, jamur) dan dapat pula dari dalam (endogen) misalnya dermatitis atopik.

Add 2. Dermatitis Kontak (Dermatitis Kontak Alergi dan Dermatitis Kontak Iritan)

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Dermatitis kontak adalah dermatitis yang disebabkan oleh bahan/substansi yang menempel pada kulit. Dermatitis kontak merupakan perdangan kulit yang disertai dengan adanya spongiosis/edema interseluler pada epidermis karena kulit berinteraksi dengan bahan-bahan kimia yang berkontak atau terpajan pada kulit.

Dermatitis kontak ini dikenal 2 macam yaitu Dermatitis Kontak Alergi dan Dermatitis Kontak Iritan. Kedua dapat bersifat akut maupun kronis.

Dermatitis Kontak Alergi (DKA) terjadi pada seseorang yang telah mengalami sensitisasi terhadap suatu alergen, sedangkan Dermatitis Kontak Iritan (DKI) merupakan reaksi peradangan kulit nonimunologik, jadi kerusakan kulit terjadi langsung tanpa didahului proses sensitisasi.

* Dermatitis Kontak Alergi/DKA

Jumlah penderita DKA lebih sedikit jika dibandingkan dengan DKI, karena DKA (Dermatitis Kontak Alergi) hanya mengenai orang yang keadaan kulitnya sangat peka/hipersensitif.

Etiologi/ penyebab DKA (Dermatitis Kontak Alergi) adalah bahan kimia sederhana dengan berat molekul umumnya rendah, merupakan alergen yang belum diproses disebut Hapten, bersifat lipofilik, sangat reaktif, dapat menembus stratum korneum sehingga mencapai sel epidermis di bawahnya (sel hidup).

Berbagai faktor berpengaruh dalam timbulnya DKA adalah : potensi sensitisasi alergen, dosis per unit area, luas daerah yang terkena, lama pajanan, oklusi, suhu dan kelembapan lingkungan, vehikulum serta pH. Selain itu juga faktor individu misalnya keadaan kulit pada lokasi kontak (keadaan atratum korneum, ketebalan epidermis), status imunologik misalnya sedang menderita sakit, terpajan sinar matahari.

Patogenesis Dermatitis Kontak Alergi (DKA) :

Dermatitis Kontak Alergi (DKA) termasuk reaksi tipe IV yang merupakan hipersensitivitas tipe lambat. Patogenesisnya melalui 2 fase yaitu induksi (fase sensitisasi) dan fase elisitasi.

Fase induksi (fase sensitisasi) : terjadi saat kontak pertama alergen dengan kulit sampai limfosit mengenal dan memberi respons, yang memerlukan 2-3 minggu. Pada fase induksi/fase sensitisasi ini, hapten (protein tidak lengkap masuk ke dalam kulit dan berikatan dengan protein karier membentuk antigen yang lengkap. Antigen ini ditangkap dan diproses lebih dahulu oleh makrofag dan sel langerhans. Kemudian memacu reaksilimfosit T yang belum tersensitisasi di kulit sehingga sensitisasi terjadi pada limfosit T. Melalui saluran limfe, limfosit tersebut bermigrasi ke darah parakortikal kelenjar getah bening regional untuk berdifferensiasi dan berproliferasi membentuk sel T efektor yang tersensitisasi secara spesifik dan sel memori. Kemudian sel-sel tersebut masuk ke dalam sirkulasi, sebagian kembali ke kulit dan sistem limfoid, tersebar di seluruh tubuh, menyebabkan keadaan sensitisasi yang sama di seluruh kulit tubuh.

Fase elisitasi terjadi saat pajanan ulang dengan alergen yang sama sampai timbul gejala klinis. Pada fase elisitasi, terjadi kontak ulang dengan hapten yang sama. Sel efektor yang telah tersensitisasi mengeluarkan limfokin yang mampu menarik berbagai sel radang sehingga terjadi gejala klinis.

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Adapun gejala klinisnya yaitu penderita umumnya mengeluh gatal. Kelainan kulit bergantung pada keparahan dermatitis dan lokalisasinya. Pada dermatitis kontak yang akut gejalanya ditandai dengan bercak eritematosa yang berbatas jelas kemudian diikuti edema, papulovesikel, vesikel atau bula. Vesikel atau bula dapat pecah menimbulkan erosi dan eksudasi (basah). DKA akut di tempat tertentu, misalnya kelopak mata, penis, skrotum, eritema dan edema lebih dominan daripada vesikel. Pada dermatitis kontak yang kronis terlihat kulit kering, berskuama, papul, likenifikasi dan mungkin juga fisur, batasnya tidak jelas. DKA dapat meluas ke tempat lain, misalnya dengan cara autosensitisasi. Skalp, telapak tangan dan kaki relatif resisten terhadap DKA.

Berbagai lokasi terjadinya DKA : tangan, lengan, wajah, telinga, leher, badan, genitalia, paha dan tungkai bawah.

*Dermatitis Kontak Iritan (DKI)

Dermatitis Kontak Iritan (DKI) dapat diderita oleh semua orang dari berbagai golongan umur, ras dan jenis kelamin. Jumlah penderita DKI diperkirakan cukup banyak, terutama yang berhubungan dengan pekerjaan, namun angkanya secara tepat sulit diketahui.

Penyebab munculnya dermatitis jenis iritan ini adalah bahan yang bersifat iritan, misalnya bahan pelarut, deterjen, minyak pelumas, asam, alkali dan serbuk kayu. Kelainan kulit yang terjadi selain ditentukan oleh ukuran milekul, daya larut, konsentrasi, dan vehikulum, juga dipengaruhi oleh faktor lain misalnya lama kontak, kekerapan terkena dermatitis kontak, adanya oklusi menyebabkan kulit permeabel, demikian pula gesekan dan trauma fisis. Suhu dan kelembapan lingkungan juga ikut berperan. Faktor individu juga ikut berpengaruh pada DKI, misalnya perbedaan ketebalan kulit di berbagai tempat menyebabkan perbedaan permeabilitas; usia misalnya anak di bwah 8 tahun dan usia lanjut lebih mudah teriritasi; ras (kulit hitam lebih tahan daripada kulit putih; jenis kelamin (DKI lebih banyak terjadi pada wanita); penyakit kulit yang pernah atau sedang di alami misalnya dermatitis atopik.

Patogenesis : Kelaianan kulit timbul akibat kerusakan sel yang disebabkan oleh bahan iritan melalui kerja kimiawi dan fisis. Bahan iritan merusak lapisan tanduk, terjadi denaturasi keratin,

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menyingkirkan lemak lapisan tanduk dan mengubah daya ikat air kulit. Kebanyakan bahan iritan (toksin) merusak membran lemak (lipid membrane) keratinosit, tetapi sebagian dapat menembus membran sel dan merusak lisososm, mitokondria atau komponen inti. Kerusakan membran mengaktifkan fosfolipase dan melepaskan asam arakhidonat (AA), diasilgliserida (DAG), platelet activating faktor = PAF, dan Inositida (IP3). Keratinosit juga membuat molekul permukaan HLA-DR dan adhesi intrasel-I (ICAM-I). Pada kontak dengan iritan , keratinosit juga melepaskan TNF alfa yang merupakan suatu sitokin proinflamasi yang dapat mengaktivasi sel-T, makrofag dan granulosit, menginduksi ekspresi molekul adesi sel dan pelepasan sitokin.

Rentetan kejadian tersebut menimbulkan gejala peradangan klasik di tempat terjadinya kontak di kulit berupa eritema, edema, panas, nyeri bila iritan kuat.

Gejala klinis berupa kelaian kulit yang terjadi beragam, tergantung pada sifat iritan. Iritan kuat memberi gejala akut, sedang iritan lemah memberi gejala kronis. Selain itu juga karena faktor individu misalnya ras, usia, lokasi atopi, penyakit kulit lainnya. Faktor llingkungan misanya suhu, kelembapan udara dan oklusi juga mempengaruhi terjadinya dermatitis kontak iritan.

Klasifikasi DKI berdasarkan penyebab dan pengaruh yaitu : DKI akut, lambat akut/acute delayed ICD, reaksi iritan, kumulatif, traumateratif, eksikasi ekzematik, pustular dan akneformis, noneritematosa dan subjektif.

Perbedaan Dermatitis Kontak Alergi (DKA) dan Dermatitis Kontak Iritan (DKI)

Dermatitis Kontak Iritan :

- Penyebab : iritan primer

- Permulaan : pada kontak pertama

- Penderita : semua orang bisa terkena

- Lesi : batas lebih jelas, eritema jelas, monomorf

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- Uji tempel : sesudah di tempel 24 jam, bila iritan diangkat, reaksi akan berhenti.

- Dermatitis Kontak Alergi (DKA) :

- Penyebab : alergen kontak S. sensitizer

- Permulaan : pada kontak ulang

- Penderita : hanya orang yang alergi

- Lesi : batas tidak begitu jelas, eritema tidak ada, polimorf

- Uji tempel : Bila sudah 24 jam, bahan alergen diangkat, reaksi menetap,meluas dan akhirnya akan berhenti juga.

Add 3. Diagnosis dan diagnosis banding Dermatitis Kontak

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* Diagnosis dan diagnosis banding DKA

Diagnosis didasarkan atas hasil anamnesis yang cermat dan pemeriksaan klinis yang teliti. Pertanyaan mengenai kontaktan yang dicurigai didasarkan kelainan kulit yang ditemukan. Misalnya ditemukan ada kelainan kulit berukuran numular disekitar pusatberupa hiperpigmentasi, likenifikasi dengan papul dan erosi. maka perlu ditanyakan apakah pasien memakai kancing celana atau kepala ikat pinggang yang terbuat dari logam. Data dari anamnesis juga harus meliputi riwayat pekerjaan, hobi, obat topikal yang pernah digunakan, obat sistemik, kosmetika, bahan-bahan yang menimbulkan alergi, riwayat atopi baik dari yang bersangkutan maupun keluarganya.

Pada kasus di atas, perlu ditanyakan apakah ada alergi menggunakan sendal jepit, bahan sendal jepit yang digunakan apakah dari karet atau logam. Ditanyakan apakah ada riwayat alergi sebelumnya, apakah ada keluarga menderita sakit yang sama karena alergi. Perlu diperhatikan juga pekerjaan pasien sebagai petani yang selalu kontak dengan tanah yang basah atau kontak dengan bahan-bahan kimia dari desinfektan untuk pembasmi hama dan pajanan yang terlalu lama di bawah sinar matahri. Perlu ditanyakan juga apakah pernah menderita sakit yang sama sebelumnya dan pernahmengkonsumsi obat-obat apa saja.

Pemeriksaan fisik penting, karena dengan melihat lokasi dan pola kelainan kulit sering dapat diketahui kemungkinan penyebabnya. Misalnya lesinya di kaki, maka dapat dipastikan penyebanya karena sendal/sepatu. Pemeriksaan hendaknya di tempat yang terang pada seluruh kulit untuk melihat kemungkinan kelaianan kulit lain karena sebab-sebab endogen.

Diagnosis bandingnya yaitu : Dermatitis Kontak Iritan (DKI), dermatitis atopik, dermatitis numularis, dermatitis seboroik atau psoriasis.

* Diagnosis dan diagnosis banding DKI

Diagnosis DKI didasarkan anamnesis yang cermat dan pengamatan gambaran klinis. DKI akut lebih mudah diketahui karena munculnya lebih cepat sehingga penderita pada umumnya masih ingat apa yang menjadi penyebabnya. Sebaliknya, DKI kronis timbulnya lambat serta mempunyai variasi gambaran klinis yang luas, sehingga adakalanya sulit dibedakan dengan dermatitis kontak alergi. Untuk itu diperlukan uji tempel dengan bahan yang dicurigai.

Diagnosa bandingnya : DKA (Dermatitis Kontak Alergi)

Add 4. Uji Tempel (Patch test)

Tempat untuk melakukan uji tempel biasanya di punggung. Untuk melakukan uji tempel diperlukan antigen, biasanya antigen standar buatan pabrik misalnya Finn Chamber System Kit dan T.R.U.E Test.

Bahan yang secara rutin dan dibiarkan menempel di kulit, misalnya kosmetik, pelembab, bila dipakai untuk uji tempel, dapat langsung digunakan apa adanya. Bila menggunakan bahanyang secara rutin dipakai dengan air untuk membilasnya, misalnya sampo, pasta gigi, maka harus diencerkan terlebih dahulu. Bahan yang tidak larut dalam air diencerkan atau dilarutkan dalam vaselin atau minyak mineral. Produk yang diketahui bersifat iritan, misalnya deterjen, hanya boleh diuji bila diduga karena penyebab alergi. Apabila pakaian, sepatu, sendal,atau sarung tangan yang dicurigai penyebab alergi, maka uji tempel dilakukan dengan potongan kecil bahan tersebut yang direndam dalam air

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garam yang tidak dibubuhi bahan pengawet/air. Lalu ditempelkan di kulit dengan memakai Finn chamber, dibiarkan sekurang-kurangnya 48 jam. Yang perlu diingat bahwa hasilpositif dengan alergen bukan standar perlu kontrol (5-10 orang), untuk menyingkirkan kemungkinan iritasi.

Hal yang harus diperhatikan dalam uji tempel adalah :

- Dermatitis harus sudah tenang (sembuh). Bila masih dalam keadaan akut atau berat maka dapat terjadi reaksi "angry back" atau "excited skin", reaksi positif palsu, dapat juga menyebabkan penyakit yang sedang dideritanya makin memburuk.

- Tes dilakukan sekurang-kurangnya satu minggu setelah pemakaian kortikosteroid sistemik dihentikan, sebab dapat menghasilkan reaksi negatif palsu. Sedangkan antihistamin sistemik tidak mempengaruhi hasil tes kecuali karena diduga urtikaria kontak.

- Uji tempel dibuka setelah 2 hari, kemuadian dibaca; pembacaan kedua dilakukan pada hari ke-3 sampai ke-7 setelah aplikasi.

- Penderita dilarang melakukan aktivitas yang menyebabkan uji tempel menjadi longgar, karena memberikan hasil negatif palsu. Penderita juga dilarang mandi sekurang-kurangnya dalam 48 jam, dan menjaga agar punggung selalu kering, setelah dibuka uji tempelnya sampai pembacaan terakhir selesai.

- Uji tempel dengan bahan standar jangan dilakukan terhadap penderita yang mempunyai riwayat urtikaria dadakan, karena dapat menimbulkan urtikaria generalisata bahkan reaksi anafilaksis.

Setelah dibiarkan menempel selama 48 jam, uji tempel dilepas. Pembacaan pertama dilakukan 15-30 menit setelah dilepas, agar efek tekanan bahan yang diuji telah menghilang atau minimal. Hasilnya dicatat seperti berikut :

1 = reaksi lemah (nonvesikuler) : eritema, infiltrat, papul (+)

2 = reaksi kuat : edema atau vesikel (++)

3 = reaksi sangat kuat (ekstrim) : bula atau ulkus (+++)

4 = meragukan : hanya makula eritematosa (?)

5 = iritasi : seperti terbakar, pustul atau purpura (IR)

6 = reaksi negatif (-)

7 = excited skin

8 = tidak dites (NT = Not Tested)

Pembacaan kedua perlu dilakukan sampai satu minggu setelah aplikasi, biasanya 72 atau 96 jam setelah aplikasi. Pembacaan kedua ini penting untuk membantu membedakan antara respon alergik atau iritasi, dan juga mengidentifikasi lebih banyak lagi respon positif alergen.

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Add 5. Penatalaksanaan dan pencegahan dermatitis kontak

* Penatalaksanaan dan pencegahan DKA

- Upaya pencegahan terulangnya kontak kembali dengan alergen penyebab dan menekan kulit yang timbul.

- Kortikosteroid dapat diberikan dalam jangka pendek untuk mengatasi peradanagn pada DKA akut yang ditandai dengan eritema, edema, vesikel, bula, eksudatif (madidans), misalnya mengkonsumsi prednison 30 mg/hari. Sedangkan kelainan kulinya cukup dikompres dengan larutan garam faal atau larutan air salisil 1: 1000.

Untuk DKA ringan atau DKA akut yang telah mereda (setelah mendapat pengobatan kortikosteroid sistemik), cukup diberikan kortikosteroid atau makrolaktam (tacrolimus) secara topikal.

* Penatalaksanaan dan pencegahan DKI

- Menghindari pajanan bahan iritan, baik yang bersifat mekanik, fisis maupun kimiawi serta menyingkirkan faktor yang memperberat. Bila dapat dilaksanakan dengan sempurna, dan tidak terjadi komplikasi, maka DKI akan sembuh sendiri, cukup dengan pelembab untuk memperbaiki kulit yang kering.

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- Apabila diperlukan, untuk mengatasi peradangan dapat diberikan kortikosteroid topikal seperti hidrokortison atau untuk kelainan yang kronis dapat diawali dengan kortikosteroid yang lebih kuat.

- Pemakaian alat pelindung diri yang adekuat, diperlukan bagi mereka yang bekerja dengan bahan iritan.

Add. 6 Prognosis Dermatitis Kontak

* Prognosis DKA

Prognosis DKA umumnya baik, sejauh bahan kontaknya dapat disingkirkan. Prognosis kurang baik dan menjadi kronis bila terjadi bersamaan dengan dermatitis oleh faktor endogen (dermatits atopik, dermatitis numularis, atau psoriasis), terpajan oleh alergen yang tidak mungin dihindari, misalnya berhubungan dengan pekerjaan tertenyu atau yang terdapat di lingkungan penderita.

Pada kasus dijelaskan bahwa pasien bekerja sebagai seorang petani, jadi selalu terpajan dengan sinar matahari dan zat kimia pada insektisida.

* Prognosis DKI

Bila bahan iritan penyebab dermatitis tersebut tidak dapat disingkirkan dengan sempurna, maka prognosisnya kurang baik. Keadaan ini sering terjadi pada DKI kronis yang penyebabnya multifaktor, juga pada penderita atopi.