The subject of the book by Kevin Tracey is fascinating: severe sepsis
and septic shock are seldom mentioned yet the death rates of these
conditions are staggering: 30-70% and 20-35% respectively. Sepsis is
the second leading cause of death in non-coronary intensive care unit
patients.

Tracey starts the book's story with a case of an infant burn victim
who suffers first from septic shock then from severe sepsis. The
struggles of this patient became the motivation for author's later
research and the refrain of this book.

It is interesting to read how modern-day doctors with all the
sophisticated life-support machinery feel impotent in the face of this
deadly condition.

Tracey then advances the theory, that he participated in developing,
of TNF and HMGB1 cytockines (molecules used for cell signaling) and
activation of white blood cells (macrophages). The uncontrolled
release of TNF leads to body-wide activation of macrophages which
change the viscosity of the blood, clog the capillaries and lead to
organ failure and death. Tracey posits that one of the functions of
the vagus nerve is to control the immune system response and to
contain it in a particular area through neutralizing HMGB1 in places
where it is not needed.  Severe sepsis is the failure of this limiting
function. The latter is apparently still a theory, at least it did not
make to the wikipeida pages. This failure is similar to causes for
autoimmune diseases such as arthritis, lupus. The implication is that
operation of the vagus nerve is influenced by the person's mood,
health, rest, etc. This would explain the mood-related flareups of
auto-immune diseases. Having to rest to fight infection and so on. 

It feels like the medical science is on the verge of a major
breakthrough in understanding of the operation of the immune system
and, hopefully, in effectively treating deadly conditions that the
doctors for ages were powerless to stop.


Tracey keeps the medical jargon to the minimum, talks with ease about
complex phenomena. The book is easy to read. He does occasionally
slip into research-grant proposal writing style. Oh, well.