127agnosed. Without any reason to suspect
otherwise, doctors have to rely on what
they know. In many cases, like that of
Ethan and Austin, they know what the
problem is but fail to unearth genetic
evidence – vital for identifying at-risk
family members and formulating a
treatment plan. Frustrated by months
or years of disjointed medical testing,
a doctor may suggest patients apply
to the UDN in a final bid for answers.
The Duke team reviews applications
in a meeting every Tuesday. In order
to be eligible, a patient must have an
“objective finding” – a first clue or loose
thread for the team to begin unravelling.
“There is a perception that ‘undiag-
nosed’ also means ‘functional’, so the
two can be confused,” explains Shashi.
“So if you have symptoms like pain or
fatigue, yes you can be undiagnosed,
but that doesn’t mean you have a true
objective undiagnosed disease. These
symptoms could be due to pre-existing
functional diseases.”
A functional disease is one that
exhibits symptoms – nausea, say,
or light-headedness – and affects
functionality. Such symptoms are
common, and easy to diagnose as
caused by common illnesses. UDN
patients may have these symptoms, but
it’s the objective finding – the unusual
clue – that makes them suitable.
Once a patient is accepted, represen-
tatives from each of the UDN sites join
a call to share suggestions regarding
possible diagnoses or tests. This culture
of collaboration means specialists can
confer in real time, working together
to find a diagnosis. The network has
the resources to examine a patient’s
history in detail and formulate a working
hypothesis based on this data, leading
to a suite of tests tailored around the
specific condition, a large part of which
involves closely examining genetic data
for rare or unusual variants or changes.‘GENETIC
EVIDENCE
IS VITAL
FOR
AT-RISK
FAMILY
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