The Role of the Pathologist in Liver Transplantation
Effective management of solid organ transplantation recipients
requires a team of physicians, familiar with complications unique
to immunosuppressed allograft recipients. An anatomical pathologist
with a special interest in transplantation pathobiology can be
an invaluable member of such a team. He/she can significantly
contribute to almost every aspect of a large transplantation program,
including recipient selection, evaluation of donor organs and
post-transplant follow-up, as well as research into new therapeutic
approaches and the understanding of disease processes. In addition,
because of the specialization required, transplant centers tend
to be regionalized. Therefore, some of the follow-up care will
often occur at smaller facilities and pathologists not familiar
with post-transplant, will at times encounter biopsies from liver
allograft recipients. In some instances, complications that arise
are relatively straightforward and can be easily handled at a
non-transplant center. However, other complications are difficult
to recognize and therefore, require considerable experience.
In such cases, close contact with experts at the regional transplant
center can be helpful. This is made easier with the advent of
electronic communications, such as e-mail and the internet. This
site is but one example.
To effectively deal with transplantation pathology, it is desirable
that the pathologist has an adequate working knowledge of four
basic areas: 1) liver pathophysiology; 2) familiarity with
clinical management problems and terminology; 3) opportunistic
infections and immunodeficiency-associated malignancies and 4)
immunopathology. These help the pathologist to correctly diagnose
the histopathological changes seen on light microscopy and effectively
communicate this information to the clinical managment team.
In addition, transplantation pathology is more "medical"
or "inflammatory" pathology rather than tumor pathology,
which comprises a significant proportion of most surgical pathology
practices. Thus, one may be asked to render an "opinion"
rather than an absolute diagnosis. For example, a patient may
develop a post-transplant lymphoproliferative disorder(PTLD) because
of over-immunosuppression. Subsequently, the immunosuppressive
therapy may be substantially reduced or withdrawn. Rejection
of the allograft may then appear, and these changes may overlap
with those seen with Epstein-Barr virus(EBV) hepatitis. The pathologist
may be asked to render an opinion whether the rejection is "severe
enough" to require therapy today, or can the treatment be
delayed until all evidence of EBV reactivity or PTLD has resolved.
Willingness to answer a question like this, and participate in
the decision-making process, requires experience with similar
situations in the past, and an understanding that the pathologist
will at times, be proven wrong. These types of situations may
be unconfortable to some, because pathologists are often thought
of as the "final check point", where the "correct"
diagnosis is rendered.
Nevertheless, I have found this type of pathology practice to
be particularly rewarding. The feedback on the correctness of
diagnoses is very quick and One can significantly contribute to
an efficient and effective management of patients who have been
given a "second chance" at life, being rescued from
endstage organ disease.