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1106 PART 10: The Surgical Patient

following any major surgery, including bacterial or candidal infections The spectrum of disease caused by CMV infection among transplant
involving the lungs, urinary tract, surgical wound, or indwelling catheters. recipients is variable. 147,148 CMV can cause direct infection, disseminated
Efforts should be made to remove all vascular-access catheters and disease as well as create a secondary immune phenomenon. Infection
drains as soon as possible. In addition, strategies to facilitate liberation can be asymptomatic or associated with an acute flu-like illness char-
from mechanical ventilation may lessen the risk for nosocomial infec- acterized by fever and myalgias. The virus can cause bone marrow sup-
tion. The high level of immunosuppression during the induction phase pression and consequently leukopenia and thrombocytopenia. Infection
contributes to the development of infections during this time period, of the allograft can cause organ-specific inflammation resulting in acute
but usually the state of immunosuppression has not been of sufficient hepatitis, pneumonitis, or myocarditis, depending on the organ that was
duration to allow many of the opportunistic infections that are prob- transplanted. Active CMV infection is also associated with the devel-
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lematic in subsequent months to develop. Occasionally infections opment of other opportunistic infections, likely due to CMV-mediated
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may be transmitted to the recipient via the allograft itself. The presence immune defects, and consequently it should be considered whenever
of bacteremia, fungemia, or active infection in a donor is generally an unusual infection (such as PJP or invasive aspergillosis) develops.
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considered a contraindication to organ donation given the associated Acute rejection has been associated with CMV infection. However,
high probability that infection will be transmitted to the host. Cultures the role of CMV infection in contributing to chronic rejection is likely
obtained at the time of implantation (eg, via bronchoscopic-guided much more important. It has been associated with the development of
lung lavage) may be used to guide treatment of the recipient. Typically bronchiolitis obliterans in lung transplant patients, the vanishing-bile-
most centers employ prophylactic antibiotic strategies to empirically duct syndrome in recipients of liver allografts, and in premature and
treat the microbes that may be potentially transplanted into the recipi- accelerated atherosclerosis of the coronary arteries following heart
ent. Parenteral, oral, topical, and/or inhaled medications are often used transplantation. Though posttransplant lymphoproliferative disease
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alone or in combination. is usually associated with EBV infection, active CMV infection has also
been implicated as a risk factor for its development. 150-152
Infections Occurring Between 1 and 6 Months Posttransplant: Allograft Two strategies have been proposed to prevent posttransplant CMV
rejection and opportunistic infections need to be considered as the cause and other herpetic infections: universal prophylaxis or preemptive
for febrile illness during this period posttransplant. The sustained immu- therapy. Universal prophylaxis refers to providing therapy to all patients
nosuppression used in the induction phase and early maintenance phase at risk for a defined period of time. In addition to reducing the risk of
leads to an increased risk of opportunistic infections. Infections due to CMV infection, it reduces the risk of other viral infections as well as
Pneumocystis jiroveci (PJP), Aspergillus spp, Listeria monocytogenes, and bacterial and fungal infections given the protection against the further
tuberculosis become important considerations. Most transplant pro- immunosuppressive impact that CMV infection could impose.
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grams routinely provide recipients with trimethoprim-sulfamethoxazole Preemptive therapy involves routine monitoring at predefined intervals
(TMP-SMX) to reduce the risk of PJP infection. Should a transplant to detect early evidence of infection and then initiate treatment before
patient develop PJP, the treatment of choice is intravenous TMP-SMX. symptoms can arise. Treatment of CMV infection generally consists of
Pentamidine can be used as an alternative, but it is associated with a intravenous ganciclovir in the immediate posttransplant period followed
greater incidence of toxicity and side effects, and is generally considered by oral valganciclovir, a highly bioavailable oral form of ganciclovir.
to be less effective therapy. In patients who have a positive purified pro- While both approaches have been shown to be effective, most centers
tein derivative tuberculosis skin test (>5 mm induration ) or who are provide universal prophylaxis for at least 3 to 6 months after transplan-
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at high-risk for reactivation of latent tuberculosis infection, prophylactic tation. Despite this, a large number of transplant patients develop CMV
therapy with isoniazid for 9 to 12 months should be considered. 144 infection within 1 year after transplant. A recent randomized, controlled
Following the first month, the recipient is at risk for infections due to trial in the lung transplant patient population demonstrated that extend-
several viruses that would normally be suppressed by an intact immune ing the CMV prophylaxis to 12 months from 3 months significantly
response. Particularly problematic are infections due to CMV, EBV, reduced CMV infection, disease, and disease severity without increased
other herpes viruses, hepatitis B and C viruses, and HIV. Screening for ganciclovir resistance or toxicity. Some experts tailor the duration to
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these viruses is usually performed in both the donor and the recipi- serostatus of the donor and recipient and continue CMV prophylaxis for
ent prior to the transplant procedure, and when feasible, prophylaxis 12 months in the setting of donor-positive and recipient-negative status,
therapy is routinely employed. However, lapses in prophylaxis or lack of and for 6 to 12 months in the setting of donor-negative and recipient-
effective prophylactic medications may have led to infection with one of positive status or donor- and recipient-positive status.
these viral pathogens. Evaluation of bronchoscopic samples from lung
transplants, tissue biopsy or evidence of viral burden in the blood stream Infections Occurring More Than 6 Months Posttransplant: Immunosuppressive
may help establish a diagnosis. therapy is often tapered by this stage; therefore, a decreased risk of infection
exists. However, severe infections occurring more than 6 months following
Infections due to Cytomegalovirus: The most common viral infection for the transplant procedure may necessitate ICU admission. Most commonly
all solid-organ transplant recipients is CMV infection. Once a person is these infections are similar to those experienced by the general community
infected by this herpes virus, they will be infected for life, though the and involve the respiratory tract. Other problems developing in this time
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virus generally remains in a latent or dormant phase. Recipients who frame include the progression of underlying infection with hepatitis B or
are seronegative for CMV that receive an allograft from a seropositive C, CMV, EBV, and human papillomavirus. There is also a continued risk
donor are at greatest risk of developing symptomatic illness, including for the opportunistic infections that develop after the first posttransplant
tissue-invasive disease from primary infection. Patients who are already month (discussed above) during this time period, and careful surveillance
seropositive for CMV prior to the procedure (indicating past exposure for their occurrence must be maintained.
and latent infection) are at risk for reactivation following the initia-
tion of immunosuppressive therapy. Superinfection by a new strain of Prophylaxis: A general overview of recommended routine prophylaxis
is outlined in Table 115-18. Detailed regimens are center specific and
CMV contracted from the allograft of a CMV-seropositive donor can
also occur. Strategies to prevent CMV infection are usually based on detailed choice of specific agents and duration may vary from center to
center. Center-specific resistance patterns would also have an impact on
the recipient’s relative risk of developing infection, with those who are
recipient-negative, donor-positive and recipient-positive, donor-negative choice of agents.
(in the case of lung transplantation) receiving the more intense regi- Lung Transplant–Specific Infectious Considerations: The incidence of
mens. The monitoring of CMV antigenemia or viral load using poly- infection in lung transplant patients is much higher than that reported
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merase chain reaction may be used to guide duration of prophylaxis and for recipients of other solid organs, presumably due to the exposure of
provide evidence of infection or emergence of a resistant strain. 146 the allograft to the external environment. 155,156 Many centers initiate

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