i have a baby who turns blue

and no one can tell me why.
10ish days ago macie's hands and feet started to turn purple all the time. like a bright, obvious purple. weird, i thought. breathing normal. eating normal.
it kept happening. so to the pediatrician we went.
"that's weird. it shouldn't be happening"
duh.
she sent us to a pediatric rheumatologist.
cbc-normal (neutrophils a little low, per usual)
cpro-normal
ekg-normal
great, right?
well, yeah. except it's getting worse.
she has a rash. everywhere.
her hands and feet don't turn purple anymore.
they turn blue. like, really blue.
and so do her lips and around her mouth.
and they stay like that for half an hour or so.
and she's crabby. all.the.time.
she gets up at night. all.the.time. shrieking.
gah!