Esikhumbeni, histamine, okuyinto esibangela ukulunywa isifuba, kwenzeka cishe kuphela mast cells. Kuvela amavili ngenxa yokuthi izitsha zesikhumba endaweni ethintekile yesikhumba ziqala ukuvuza. I-Histamine yenza amaseli wemithambo yegazi asuke komunye nomunye ngokubophezela ezakhiweni ezithile (i-histamine receptors) kumaseli wemithambo yegazi futhi ngaleyo ndlela akhombise amaseli emithambo yegazi ukuthi kufanele aqhelelane. Lokhu kuvumela uketshezi lwegazi namanye amangqamuzana egazi ukuba abaleke engaphakathi komkhumbi aye ezicutshini ezizungezile. Ngokungeziwe ku-histamine, imikhiqizo yamaseli amakhulu njenge i-leukotrienes noma ezinye izithunywa (okuthiwa ama-cytokines) zingakhuphula ukungena kwemithambo yegazi. Umphumela wezidakamizwa ezilwa nokulunywa ezimweni ze-urticaria ungachazwa ngeqiniso lokuthi le mithi ivimbela ikakhulukazi ukubopha kwe-histamine kuma-histamine receptors. Ngakho-ke le mithi ibizwa ngama-antihistamine. Iqiniso lokuthi ama-antihistamine awasizi ku wonke amacala e-urticaria kukhombisa ukuthi i-histamine akuyona ukuphela kwento enxenxa ukulunywa futhi isifuba edlala indima lapha.

Avulwa kanjani ama-mast cell ngokuhlobene nezinhlobo ezahlukahlukene ze-urticaria?

Lo mbuzo ungaphendulwa kalula maqondana ne-urticaria yokungezwani komzimba, uhlobo olungavamile lwe-urticaria engapheli. I-mast cell yiseli lokugcina lokungezwani komzimba futhi ibandakanyeka kukho konke ukungezwani komzimba okulamulwa yiprotheni immunoglobulin E (IgE) futhi ngaleyo ndlela ibhekele izimpawu ze ufuba, hay fever, noma eczema. Izindlwana zingadala ukwenziwa kwe-mast cell cell, okungukuthi, ukwenziwa kusebenze yi-IgE kanye ne-allergen (into engadala ukusabela okweqile). Esimweni esinjalo, izakhi zomzimba zingena emzimbeni kanye nokudla noma umoya ophefumulwayo (isib. Impova yesihlahla, impova yotshani, udoti wasendlini) bese kusebenza izingqamuzana zemasti, ezilayishwa ngama-antibody ahambisanayo e-IgE. Imvamisa, ukumuncwa kokudla okuphendula ngokweqile kungadala i-urticaria noma ngabe kukhona ukungezwani okunjalo.

Noma yimuphi umuntu angaba iguliswa ngokuhamba kwakhe noma impilo yakhe. Lokhu kwenzeka uma sikhuthazeka ngempova ethile efana ne-birch pollen ngemuva kokuxhumana nempova. Ukuzwela kubhekise ekukhiqizweni kwama-immunoglobulin (ama-anti-protein) alwa nento ethile, kusibonelo sethu ngokumelene ne-birch pollen. Uma sivuselelwa, imizimba yethu ikhiqiza ama-immunoglobulin ahlukahlukene anemisebenzi ehlukile. Uhlobo lwe-E immunoglobulins (ama-IgEs) olwakhiwe amaseli wokuvikela amasosha omzimba, ngokwesibonelo, abambeka kumasayithi alungiselelwe ngokukhethekile kuma-mast cell (ama-IgE receptors) lapho edlula emzimbeni womuntu. Manje, lapho imizimba yethu iphinda ihlangana ne-birch pollen, ama-IgE anamathela kuma-IgE receptors kumaseli wemasti abona impova ye-birch bese eyiqoqa. Iseli le-mast lapho i-IgE inamathele khona impova ye-birch linamathele liyasebenza futhi likhipha i-histamine yalo. Ukusabela okweqile kwenzeka. Le ndlela efundwe kahle kakhulu yokusebenza kwe-mast cell itholakala kuphela engxenyeni encane yazo zonke iziguli ze-urticaria.

Kaningi ukwakheka kwama-antibodies (imizimba yokuvikela amaprotheni) ngokumelene ne-IgE receptor noma i-IgE eboshelwe kuyo kubonakala sengathi inesibopho se-urticaria. Kuze kube ngamaphesenti angama-30 eziguli ezine-urticaria engapheli, ama-antibodies alwa nezinto zomzimba angatholakala. Ngamanye amagama, umzimba uyaziphendulela. Ngakho-ke, omunye ukhuluma ngama-autoantibodies futhi i-urticaria yokuzimela. Isivivinyo esilula sokuba khona kwe-urticaria ezenzakalelayo yimijovo yegazi laso lesiguli, noma ingxenye engamanzi yegazi, esikhunjeni sangaphambili. Ezigulini ezinamasosha omzimba alwa ne-IgE receptor noma i-IgE yazo, lokhu kubangela ukwakheka okukhulu kwamasondo.

Uhlelo lokuncoma luyinto ebalulekile kunethiwekhi yokuzivikela komzimba. Izibopho zayo eziyinhloko zibandakanya ukubhujiswa okuqondile kwamaseli nama-ejenti (njengamagciwane noma ama-parasites) kanye nokusebenza kwamasosha omzimba. Ukwenza kusebenze kohlelo lokugcwalisa, isb. Kumongo wokutheleleka ngamagciwane, kuholela ekukhishweni kwezinto ezinamandla ezenza i-mast-cell isebenze. Imvamisa, i-urticaria engalapheki ibangelwe ukutheleleka okungamahlalakhona (isb. Kwezono ze-paranasal, amalaka, i-mucosa yesisu, noma amazinyo): kuyaziwa ukuthi ukususwa kokugxila okungapheli kokutheleleka kungaholela ekuphulukisweni i-urticaria engapheli. Lokhu kubizwa i-urticaria ngenxa yokutheleleka.

Igama ukungabekezelelani urticaria isetshenziswa ezimweni lapho umzimba ungakwazi ukubekezelela into ethile. Ukungakhululeki kwenzeka ngenxa yokungabekezelelani ezintweni ezinjengemithi, izivimbelakuvunda, noma udayi ekudleni. Ukugwema isithako esidala, isb. Ngokusebenzisa indlela yokudla, kungaletha ukuphulukiswa.