I-Phenylketonuria yisifo esivezwa yi-phenylalanine.

I-Phenylalanine iyi-amino acid ebalulekile enendima ebalulekile ohlelweni lwezinzwa ngokushukumisa indlala yegilo. Le i-amino acid ayenziwa umzimba ngakho-ke kufanele ihlinzekwe by ukudla. Ngempela, i-phenylalanine ingesinye sezakhi zokudla konke okunothile kumaprotheni wemvelaphi yezilwane nemifino: inyama, inhlanzi, iqanda, isoya, ubisi, ushizi, njll.

Yisifo esingajwayelekile sofuzo nesofuzo esithinta amantombazane nabafana, ngaphandle kokubheka okuthile.

Uma lesi sifo singatholakali kusenesikhathi ukwelashwa okusheshayo, ukuqongelela kwalesi sakhi kungenzeka emzimbeni futhi ikakhulukazi ohlelweni lwezinzwa. I-phenylalanine eningi kakhulu ebuchosheni obusakhulayo inobuthi.

I-phenylalanine eyeqile emzimbeni ikhishwa ngohlelo lwe-renal ngakho-ke itholakala kumchamo wesiguli, ngendlela yama-phenylketones. (2)

EFrance, ukuhlolwa kokuhlolwa kwe-phenylalanine kuhlelekile ngesikhathi sokuzalwa: Ukuhlolwa kweGuthrie.

Ukwanda (isibalo sabantu abanalesi sifo emphakathini ngesikhathi esithile), kuncike ezweni elithintekayo futhi kungahluka phakathi kuka-1/25 no-000/1.

EFrance, ukwanda kwe-phenylketonuria yi-1 / 17. (000)

Lesi sifo silashwa ngokudla okungenawo amaprotheni amaningi ukunciphisa izinga le-phenylalanine emzimbeni wesiguli futhi kunciphise ukulimala kobuchopho.

Ukwelashwa kwasekuqaleni kwalesi sifo kuvame ukuthuthukisa ukuvela kwezimpawu.

Ngaphezu kwalokho, ukwelashwa sekwedlule isikhathi okuholela ekuqongeleleni kwalemolekyuli ebuchosheni kunemiphumela ethile: (3)

- ubunzima bokufunda;

- ukuphazamiseka kokuziphatha;

- izithuthwane;

- eczema.

Izinhlobo ezintathu zalesi sifo zikhonjisiwe ngemuva kokuhlolwa kwegazi lapho kuzalwa: (2)

- I-phenylketonuria ejwayelekile: ene-phenylalaninemia (izinga le-phenylalanine egazini) elingaphezu kuka-20 mg / dl (noma 1 μmol / l);

- i-atypical phenylketonuria: ngezinga eliphakathi kuka-10 no-20 mg / dl (noma 600-1 µmol / l);

- I-hyperphenylalaninemia ehlala njalo (HMP) lapho i-phenylalaninemia ingaphansi kuka-10 mg / dl (noma i-600 μmol / l). Leli fomu lesifo alibi kakhulu futhi lidinga ukuqashwa okulula ukuze kugwenywe noma yikuphi ukwenyuka.

Ukuhlolwa okuhlelekile ngesikhathi sokuzalwa kwenza ukuthi, ezimweni eziningi, kunciphise ukubonakala kwezimpawu zesifo.

Ukwelashwa kwalesi sifo kusekelwe ekudleni okuphansi kwamaprotheni nokuqapha i-phenylalaninemia futhi kusiza ukuvimbela ukuqoqwa kwe-phenylalanine emzimbeni ikakhulukazi ebuchosheni. (2)

Uma kwenzeka ukuthi ukuxilongwa kwe-neonatal kungenziwanga, izimpawu ze-phenylketonuria zivela ngokushesha ngemva kokuzalwa futhi zingase zibe nzima kakhulu kuye ngokuthi uhlobo lwesifo lunjani.

Lezi zimpawu zibonakala nge:

- ukubambezeleka kokukhula kwengqondo kwengane;

- ukubambezeleka kokukhula;

- i-microcephaly (usayizi omncane kakhulu wogebhezi);

- ukudlikizela nokuthuthumela;

- eczema;

- ukuhlanza;

- ukuphazamiseka kokuziphatha (ukungasebenzi kahle);

- iziyaluyalu motor.

Endabeni ye-hyperphenylalaninemia, ukuguquka kwezakhi zofuzo okufaka i-co-factor yokuguqula i-phenylalanine ibe yi-tyrosine (i-co-factor BHA) kungenzeka. Lokhu kuphazamiseka ekukhiqizeni i-tyrosine kuholela ku:

- isikhumba esifanele;

- izinwele ezifanele.

I-Phenylalanine isifo sofuzo esitholakala ngofuzo. Umphumela wefa le-autosomal recessive. Le ndlela yokudlulisela ithinta i-autosome (i-chromosome engeyona ezocansi) kanye nokubuyela emuva kuholela esidingweni sokuthi isihloko sibe namakhophi amabili e-allele eguquliwe ukuze kuthuthukiswe i-phenotype enesifo. (4)

Imvelaphi yalesi sifo ukuguqulwa kohlobo lwe-PAH (12q22-q24.2). Le khodi yofuzo ye-enzyme evumela i-hydrolysis (ukubhujiswa kwento ngamanzi): i-phenylalanine hydroxylase.

Ngakho-ke isakhi esiguqukile siphumela ekwehliseni umsebenzi we-phenylalanine hydroxylase ngakho-ke i-phenylalanine evela ekudleni ayicutshungulwa kahle ngumzimba. Izinga lale-amino acid egazini lesihloko esithintekile liyanyuka. Ngemuva kokukhuphuka kwaleli nani le-phenylalanine emzimbeni, ukugcinwa kwalo kuzokwenzeka ezithweni ezihlukene kanye / noma ezicutshini, ikakhulukazi ebuchosheni. (4)

Ezinye izinguquko ziye zaboniswa ebuhlotsheni nalesi sifo. Lokhu kungukuguqulwa ezingeni lezakhi zofuzo ezifaka ikhodi ye-BHA (co-factor yokuguqulwa kwe-phenylalanine ibe yi-tyrosine) futhi ikakhulukazi ikhathalela uhlobo lwe-hyperphenylalaninemia. (1)

Izici ezinobungozi ezihambisana nalesi sifo ziyizakhi zofuzo. Eqinisweni, ukudluliswa kwalesi sifo kwenzeka ngokudluliswa ngokweqile kwe-autosomal. Kuphakathi kokuthi ukutholakala kwama-alleles amabili okushintshelwe isakhi sofuzo kumele kube khona kumuntu ukuze athuthukise lesi sifo.

Ngalo mqondo, umzali ngamunye womuntu ogulayo kufanele abe nekhophi yesakhi sofuzo esiguqukile. Ngoba kuyifomu eguquguqukayo, abazali abanekhophi eyodwa vo yesakhi esiguqukile abakhombisi izimpawu zesifo. Noma kunjalo, ziyadingeka, kuze kufike ku-50% lilinye, ukuze ngamunye adlulisele isakhi sofuzo esitshintshile enzalweni. Uma ubaba nomama wengane ngamunye ehambisa isakhi sofuzo esiguqukile, ngakho-ke isihloko sizoba nama-alleles amabili aguqukile bese sithuthukisa i-phenotype enesifo. (4)

Ukuxilongwa kwe-phenylketonuria kwenziwa ikakhulukazi ngohlelo lokuhlola ukuzalwa: ukuhlolwa okuhlelekile kwezinsana. Lokhu ukuhlolwa kweGuthrie.

 Lokhu kuhlolwa kubhekwa njengokuhle uma izinga le-phenylalanine egazini likhulu kune-3 mg / dl (noma i-180 µmol / l). Ngokwesimo se-phenylalaninemia eyeqile, ukuhlolwa kwegazi kwesibili kwenziwa esikhungweni esikhethekile ukuqinisekisa noma cha ubukhona be-phenylketonuria. Uma izinga le-phenylalanine liselikhulu kune-3 mg / dl ngesikhathi somthamo wesibili futhi asikho esinye isifo esingahle sitholakale, kutholakala ukuxilongwa. (2)

Ukutholakala kwalesi sifo kufanele kuhlukaniswe nokuntuleka kwe-BH4. Ngempela, lokhu okugcina kuyisici se-hyperphenylalaninemia futhi kudinga ukuqapha okulula kuphela. Ngenkathi ukutholakala kobukhona be-phenylketonuria esihlokweni kudinga ukwelashwa okukhethekile kanye nokudla okuphansi kwamaprotheni. (1)

Ukwelashwa okuyinhloko kwe-phenylketonuria ngakho-ke kungukudla okuphansi kwe-phenylalanine, okusho ukunciphisa ukuncipha kokudla kwamaprotheni. Lokhu kudla kwamaprotheni okuphansi kufanele kusetshenziswe ngokushesha lapho kwenziwa ukuhlolwa kwezinsana. Kumele ilandelwe impilo yonke futhi ingaqina kakhulu ngokuya ngesihloko nangendlela yesifo. (2)

Ngaphezu kwalokhu kudla okuphelelwe yi-phenylalanine, i-sapropterin dihydrochloride ingabekelwa isiguli ukuze ukudla kwaso kungabi namandla, noma nokuthi ukudla okudlayo kuhlale kuyinto ejwayelekile. (2)

Ngaphezu kwalokho, izithako zokudla ezicebile ngama-amino acid (ngaphandle kwe-phenylalanine), amavithamini namaminerali kunganconywa ukuze kubuyiselwe ukungalingani kulokhu kungena ngenxa yalokhu kudla. (3)

Ukusetshenziswa kwe-aspartame (i-sweetener yokwenziwa esetshenziswa emikhiqizweni eminingi efana neziphuzo zasezimbonini, amalungiselelo okudla, njll.) kufanele kugwenywe ngokuphelele kubantu abane-phenylketonuria. Eqinisweni, uma isingenile, i-aspartame iguqulwa emzimbeni ibe yi-phenylalanine. Ngalo mqondo, kwandisa ubungozi bokunqwabelana kwaleli molecule emzimbeni kanye nezingozi zokuba nobuthi kumuntu ogulayo. I-Aspartame nayo ikhona emithini eminingi, ukunakwa okukhethekile ezigulini kuyadingeka lapho uthatha izidakamizwa ezithile.

Mayelana nokuvikela, njengoba ukudluliswa kwalesi sifo kungofuzo, imindeni ethintekile yilesi sifo ingathola usizo nezeluleko zofuzo.

Isibikezelo siyahlukahluka kuye ngesiguli nangendlela yesifo.