I-Diamond-Blackfan Anemia

Isifo se-Diamond-Blackfan anemia sithinta ngokuyinhloko umnkantsha. Ukungalungi kahle komzimba okuthinta izingxenye eziningi zomzimba kuvamile kubantu abanalesi sifo.

Injongo eyinhloko yomnkantsha iwukwenza amangqamuzana egazi amasha. Ukungasebenzi kahle komnkantsha ku- Diamond-Blackfan anemia, okuholela ekuntulekeni kwamangqamuzana abomvu egazi ukuze anikeze umoya-mpilo ezicutshini zomzimba. I-anemia (ukuntuleka kwamangqamuzana abomvu egazi) ngokuvamile ibonakala phakathi nonyaka wokuqala wokuphila. Ukukhathala, ubuthakathaka, nokubukeka okuphaphathekile ngendlela engavamile konke kuyizimpawu ze-anemia (pallor).

Iziguli ezine-anemia ye-Diamond-Blackfan zisengozini enkulu yokuba nenani lemiphumela ebalulekile ngenxa yomnkantsha wazo onephutha. Banengozi ephezulu kune-avareji yokuthuthukiswa i-myelodysplastic syndrome (MDS), isimo lapho amangqamuzana egazi angavuthiwe angakhuli ngendlela evamile. Umuntu one-anemia ye-Diamond-Blackfan kungenzeka ukuthi abe nomdlavuza womnkantsha obizwa ngokuthi i-acute myeloid leukemia (AML), uhlobo lomdlavuza wamathambo olwaziwa nge-osteosarcoma, kanye neminye imidlavuza.

Ukungajwayelekile ngokomzimba kuthinta cishe uhhafu wabantu abane-anemia ye-Diamond-Blackfan. Bangase babe nekhanda elincane (microcephaly) kanye nezinwele ezimfushane zangaphambili, kanye nezici zobuso ezihlukile ezifana namehlo abanzi (hypertelorism), amajwabu amehlo alengayo (ptosis), ibhuloho elibanzi, eliyisicaba lekhala, elincane, isethi ephansi. izindlebe, nomhlathi omncane ongezansi (micrognathia). Abantu abathintekile bangase futhi babe nolwanga oludabuke (imbobo ophahleni lomlomo) olunodebe olungaphezulu noma olungenalo (udebe oluvulekile). Bangase babe nentamo emfishane, enolwelwesi, amahlombe amancane naphakeme kunokuvamile, kanye nezinto ezingaqondakali ezandleni zabo, okuvame kakhulu okuyizithupha ezikhubazekile noma ezingekho. Ingxenye yesithathu yalabo abathintekayo banciphise ukukhula, okubangele ukuphakama okufushane.

Ezinye izimpawu ze- Diamond-Blackfan anemia zihlanganisa ukufiphala kwelensi yamehlo (i-cataract), ukwanda komfutho wamehlo (i-glaucoma), namehlo angaboni ngaso linye (strabismus). Ukukhubazeka kwezinso, ukukhubazeka kwesakhiwo senhliziyo, futhi, kwabesilisa, ukuvuleka kombhobho ongaphansi kwesitho sangasese sowesilisa kuyizimpawu ezingaba khona (hypospadias).

Ngisho nangaphakathi komndeni ofanayo, izinga le-Diamond-Blackfan anemia lingahluka. Abantu abane-anemia “engeyona eye-classical” ye-Diamond-Blackfan bayanda kakhulu. Izimpawu zalolu hlobo lwesifo zivame ukuba mnene. Abanye abantu abathintekile, ngokwesibonelo, baba ne-anemia emaphakathi kamuva ebuntwaneni noma eminyakeni yobudala, kuyilapho abanye benezinye zezimpawu ezingokomzimba kodwa kungabikho ukungahambi kahle komnkantsha.

Izimbangela ze-Diamond-Blackfan anemia

Ukuguqulwa kofuzo lwe-RPL5, RPL11, RPL35A, RPS10, RPS17, RPS19, RPS24, kanye ne-RPS26, phakathi kokunye, kungabangela i-Diamond-Blackfan anemia. Lezi kanye nezinye ikhodi yofuzo lwe-Diamond-Blackfan anemia yamaprotheni e-ribosomal, ayizingxenye zezinhlaka zamaselula ezaziwa ngokuthi ama-ribosomes. Ama-Ribosomes adala amaprotheni ngokucubungula imiyalelo yofuzo yeseli.

Ama-subunits amakhulu namancane e-ribosome ngayinye akhiwe izingxenye ezimbili (ama-subunits). Izakhi zofuzo ze-RPL5, RPL11, kanye ne-RPL35A zikhiqiza amaprotheni e-ribosomal atholakala ku-subunit enkulu. Izinhlobo zofuzo ze-RPS10, RPS17, RPS19, RPS24, kanye ne-RPS26 zikhiqiza amaprotheni atholakala kuyunithi encane.

Ukwakheka nokuqina kwe-ribosome kusizwa amanye amaprotheni e-ribosomal. Abanye basiza endimeni eyinhloko ye-ribosome ye-protein synthesis. Amanye amaprotheni e-ribosomal angase futhi adlale ezinye izindima kuseli, njengokubamba iqhaza ezindleleni zokubonisa amakhemikhali, ukulawula ukuhlukana kwamaseli, nokulawula ukuzibhubhisa kwamangqamuzana, ngokocwaningo (i-apoptosis).

Ukuguqulwa kofuzo kwe-RPS19 kubonakala cishe engxenyeni yesine yalabo abane-anemia ye-Diamond-Blackfan. Ukuguqulwa kofuzo kwe-RPL5, RPL11, RPL35A, RPS10, RPS17, RPS24, noma RPS26 kuthinta amaphesenti engeziwe angama-25 kuya kwangu-35 abantu abanalesi simo. Ukungasebenzi kahle kwe-ribosome kucatshangwa ukuthi kubangelwa ukuguquka kwezakhi zofuzo kunoma iyiphi yalezi zakhi. I-anemia kucatshangwa ukuthi ibangelwa ukuntuleka kwama-ribosomes asebenzayo, okubangela ukuzibhubhisa kwamangqamuzana akha igazi emnkantsheni wamathambo. Ezinye izinkinga zezempilo ezihlobene ne-Diamond-Blackfan anemia ingase ibangelwe ukulawulwa kokuhlukaniswa kwamaseli okungavamile noma ukucupha kwe-apoptosis engafanele. Ososayensi bazama ukuthola ukuthi kungani ukuphazamiseka kwegazi nokuphazamiseka kwezempilo kwehluka kangaka kumuntu nomuntu.

Izigameko ezisele ze-Diamond-Blackfan anemia zibangelwa ukuguqulwa kwezakhi zofuzo ezihlukahlukene, ezinye zazo ezingakatholakali. Nakuba izimo eziningi ze- Diamond-Blackfan anemia zibangelwa ukuguquka kwezakhi zofuzo ezinikeza imiyalelo yamaprotheni e-ribosomal, ukuguqulwa kwezakhi zofuzo ezithinta amaprotheni asebenzisana namaprotheni e-ribosomal noma ukudlala ezinye izindima ezinqubweni zokwakhiwa kwegazi kuye kwabonakala kubantu abambalwa abanalesi sifo.

Ukuxilongwa kwe-Diamond Blackfan anemia

Isilinganiso seminyaka yokwethula i-anemia yizinyanga ezimbili kanti isilinganiso seminyaka yokuxilongwa nge-DBA yizinyanga ezi-3-4. Okunye ukuhlola okusiza ekuxilongeni i-DBA yilezi:

• isibalo segazi esiphelele (CBC)
  • amanani enombolo yamaseli abomvu egazi, amaseli amhlophe egazi, namaplatelet kusampula yegazi.
• i-reticulocyte count (i-retic)
  • Inani lamangqamuzana egazi abomvu angavuthiwe noma amancane; inikezwa njengephesenti.
• ivolumu ye-corpuscular (MCV)
  • I-MCV isilinganiso sosayizi wamaseli abomvu egazi futhi itholakala njengengxenye ye-CBC. I-MCV inyuselwa iminyaka yobudala ezigulini ezine-DBA.
• I-erythrocyte adenosine deaminase (eADA) izinga lomsebenzi
  • Amazinga e-eADA aphakeme akhona cishe ku-80-85% weziguli ezine-DBA.
• ukuhlolwa kofuzo
  • Ukuhlolwa kofuzo kungakhomba uguquko cishe ku-80-85% weziguli ezine-DBA.

Ukwelashwa kwe-Diamond-Blackfan anemia

Izinkomba nezimpawu zabanye abantu zincane kangangokuthi akudingekile ukuba belashwe. Kungase kuhilele okulandelayo kulabo abadinga ukwelashwa: [3] \sCorticosteroids: Ezinganeni ezineminyaka engaphezu konyaka owodwa, imithi ye-corticosteroid iyelulekwa; lokhu kwelashwa kungathuthukisa inani legazi elibomvu cishe kuma-80% eziguli ezine-anemia ye-Diamond-Blackfan ekuqaleni. I-Prednisone iphathwa ngomlomo kanye ngosuku, ekuseni, ngethamo lika-2 mg/kg/ngosuku. Uma kungekho ngcono okubonakala ngemva kwenyanga, i-corticosteroids iyancishiswa futhi imisiwe.
Ukumpontshelwa igazi kusetshenziswa kanye ne-corticosteroids noma kubantu abangaphenduli kuma-corticosteroids.

Ukufakelwa komnkantsha wamathambo: Iwukuphela kokwelashwa kwe-anemia okwelaphayo; Nokho, iziguli kufanele ziqashwe ngoba zisengozini ephakeme yomdlavuza wegazi kanye nomdlavuza. Lapho osemncane oneminyaka engaphansi kweminyaka eyishumi ubudala etshalwa kabusha ngengane yakubo ehambisana ne-HLA, imiphumela iba ngcono.

Iziyaluyalu ezihlobene

Izifo ezilandelayo zinezimpawu ezifana ne-DBA. Ukuze uthole ukuxilongwa okuhlukile, ukuqhathanisa kungase kube nolwazi.

I-anemia ye-aplastic ichazwa ngokuhluleka komnkantsha wamathambo. I-anemia ye-aplastic ibonakala ngokucindezelwa okuphelele noma i-aplasia yomnkantsha. Ukugula kungase kukhule ngenxa yezizathu ezingaziwa, noma ngenxa yokutheleleka noma ukusabela okunobuthi emisebeni, imithi, noma amakhemikhali. Lesi sifo singabangelwa isimila ku-thymus ezimweni ezingavamile. Umnkantsha we-Hypoplastic kanye ne-aplastic yizinhlobo ezimbili zomnkantsha. I-Hypoplasia yenzeka lapho umnkantsha wonakele noma usebenza kancane, futhi i-aplasia yenzeka lapho umnkantsha uyeka ukukhiqiza amangqamuzana egazi amasha.

Esinye isimo esingavamile sokungasebenzi komnkantsha wezofuzo i-Fanconi anemia. Ukukhubazeka kokuzalwa njengokungajwayelekile kwamathambo, usayizi wekhanda elincane, izitho zangasese ezincane, nombala wesikhumba ongajwayelekile kuyayiveza. Izibalo eziphansi zegazi elimhlophe zingaholela ezifweni ezihlanganisa inyumoniya kanye ne-meningitis, kanye nezibalo eziphansi zeplatelet, ezingabangela ukopha okungavamile. Lezi ziguli zisengozini enkulu yokuthola i-leukemia nezinye izifo eziyingozi.

(Sebenzisa imishwana yosesho ethi “aplastic” kanye “Fanconi” kusizindalwazi se-Rare Disease ukuze ufunde kabanzi ngalezi zimo.)