Dear Anne Robb,
This baby is definately in trouble and if mom continues this course there is
potential for irreversable damage ( remember the Wall Street Journal article!
).
The true diagnosis of FTT has a formula of dropping a certain % in standard
deviations and I am sorry I don't have that here at home.
It sounds like mom has lost her milk supply and I would recommend her pumping
to help bring it back up but this baby needs calories sooner than that. Is
there a milk bank near by?  Better yet does she know someone who is currently
lactating and to work out something with them untill mom's milk supply is
better.
Ways to supplement this baby can varry from this group and what mom is
willing to do.  These include: a SNS, finger feeding, or cup feeding.  I
would gently but persistently keep in contact with her.  Maybe contact a
pediatrician you know and run this case by them and then let this mom hear
thier recommendations.
Now for the pediatricians that are her currrent clinicians --- ARE THEY
IGNORANT?
I can see how they may not be concerned with the lack of stools ( even though
this is a definate red flag ) but not to know what uric crystals are and not
be concerned!
I once called a pedi's office concerned with a potential dehydration and
persistently got them to recognize the importance of close monitoring and to
hear my care plan.
Keep us posted and good luck.
Ann Perry RN IBCLC