Doc­tors can now reach foe­tuses in womb

Mother and child are the first pa­tients in an ex­per­i­ment that pushes the lim­its of foetal ther­apy, com­bin­ing blood trans­fu­sions and bone mar­row trans­plants while the child is still in the womb

The East African - - FRONT PAGE - By DENISE GRADY New York Times News Ser­vice

Vi≥uses like tha­lassemia majo≥ can kill ba­bies befo≥e they a≥e bo≥n

In the three months be­fore she was even born, Elianna Con­stantino re­ceived five blood trans­fu­sions and a bone-mar­row trans­plant. All were given with a nee­dle passed through her mother’s ab­domen and uterus, into the vein in her um­bil­i­cal cord.

Elianna, born Fe­bru­ary 1 with a ro­bust cry and a cap of gleam­ing black hair, has a ge­netic dis­ease that usu­ally kills a foe­tus be­fore birth. The con­di­tion, al­pha tha­lassemia ma­jor, leaves red blood cells un­able to carry oxy­gen around the body, caus­ing se­vere anaemia, heart fail­ure and brain dam­age.

The trans­fu­sions in the womb kept her alive, but only treated her ill­ness. The bone-mar­row trans­plant has the po­ten­tial to cure it. Whether it will suc­ceed is still too soon to tell.

Elianna and her mother, Nichelle Obar, were the first pa­tients in an ex­per­i­ment that pushes the lim­its of foetal ther­apy, a field al­ready known for its dar­ing.

If the treat­ment works, it could open the door to us­ing bone-mar­row trans­plants be­fore birth to cure not just Elianna’s blood dis­ease but also sickle cell anaemia, haemophilia and other hered­i­tary dis­or­ders, some so se­vere that the pre­na­tal di­ag­no­sis may lead par­ents to end the preg­nancy.

Bone mar­row is con­sid­ered a po­ten­tial cure be­cause it teems with stem cells, which can create re­place­ments for cells that are miss­ing or de­fec­tive as a re­sult of ge­netic flaws.

“This line of work moves the field of foetal surgery, which cur­rently con­sists of big op­er­a­tions for anatomic dis­or­ders, in a new di­rec­tion of molec­u­lar and cel­lu­lar ther­a­pies given non­in­va­sively,” said Dr Tippi Macken­zie, a pe­di­atric and foetal sur­geon who is lead­ing the study at the UCSF Be­nioff Chil­dren’s Hos­pi­tal San Fran­cisco, part of the Uni­ver­sity of Cal­i­for­nia, San Fran­cisco.

Obar, 40, and her hus­band, Chris Con­stantino, 37, are healthy but learned dur­ing her first preg­nancy that they are tha­lassemia car­ri­ers. There are sev­eral forms of the dis­ease, and world­wide about 100,000 chil­dren a year are born with se­vere cases. Mil­lions of peo­ple are car­ri­ers, most com­monly those from

Asia, the Mediter­ranean, Africa or the Mid­dle East.

Car­ri­ers are gen­er­ally healthy, but when two have chil­dren to­gether, the chil­dren are at risk for the dis­ease. Obar’s an­ces­try is Filipino and Puerto Ri­can; her hus­band’s is Filipino. They live in Ki­lauea, on the Hawai­ian is­land of Kauai.

Their first child, Gabriel, now 3, is healthy. But each child they con­ceive has a one-in-four chance of be­ing af­fected, and dur­ing Obar’s se­cond preg­nancy, her doc­tors were on the look­out for the dis­ease.

They found it. An ul­tra­sound at 18 weeks showed that Elianna’s heart was twice the size it should have been, and fluid was ac­cu­mu­lat­ing around her lungs and other or­gans. Blood flow through her brain was ab­nor­mally rapid, a sign of se­vere ane­mia.

Ev­ery­thing pointed to­ward al­pha tha­lassemia ma­jor — the worst form of the dis­ease. Obar’s doc­tor and ge­netic coun­sel­lor warned her and her hus­band that their daugh­ter might not sur­vive.

“Her heart was work­ing so hard,” Obar said, with tears in her eyes.

By this point in preg­nancy, the se­cond trimester, an af­fected foe­tus has lit­tle or no work­ing haemoglobin, the mol­e­cule that car­ries oxy­gen to cells all over the body. Tis­sues are suf­fo­cat­ing, and the heart strug­gles to com­pen­sate.

Some med­i­cal ref­er­ences de­scribe the ill­ness as “in­com­pat­i­ble with life,” and most foe­tuses die in the womb from heart fail­ure. The preg­nancy may end in mis­car­riage, and par­ents may not know why. Many do not know they are car­ri­ers.

Some­times, as the foe­tus weak­ens, a phe­nom­e­non called mir­ror syn­drome oc­curs: The mother also be­comes ill, with se­vere high blood pres­sure and other prob­lems that can kill her un­less the preg­nancy is ended.

In­fants with un­treated al­pha tha­lassemia ma­jor who some­how sur­vive un­til birth al­most al­ways have se­vere brain dam­age from lack of oxy­gen.

Trans­fu­sions into the um­bil­i­cal cord dur­ing preg­nancy can save the foe­tus and may pre­vent brain dam­age. The child will then re­quire trans­fu­sions ev­ery three or

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