Renal transplant offers the best therapy for end-stage renal disease but patients face many medical complications. These include side effects of immunosuppressive drugs, infections, surgical complications, and rejection. Emergency physicians must be aware of these risks and understand each patient's medical history, drug regimen, and the pathogens common at their institution. Fever is common and could indicate opportunistic infections, especially in the first six months post-transplant. Physicians should consider infections like CMV, as well as surgical issues, rejection, or drug toxicity when evaluating transplant patients. Close communication with transplant teams is important for management.
1. Renal transplant offers the best therapy for end-stage renal disease. However, these patients
can have many different medical complications. They range from side effects of potent
immunosuppressive drugs or from drug interactions, renal tract problems, respiratory
infections, fever, post-surgical complications, cardiovascular, gastrointestinal, neurologic,
endocrine and electrolyte imbalance. Emergency physicians need to be aware of the
complications and special factors associated with renal transplant patients.
In general, a single kidney is transplanted in the right or left lower quadrant of the abdomen.
Living donor transplants function immediately, while 30% of cadaver transplants undergo
delayed graft function due to prolonged cold ischemic preservation. The renal transplant
recipient will now require long term immunosuppression to prevent rejection. The current
regimen is based on a triple therapy approach that includes cyclosporine-microemulsion or
tacrolimus, mycophenolatemofetil or azathioprine and corticosteroids. Antilymphocyte
antibodies are also widely used with the triple therapy regimen. While the current
immunosuppressive regimens are more potent which leads to less rejection, there is a greater
incidence of medication-related problems.
Rejection is the only unique cause for renal failure in kidney transplant patients. Two common
causes of acute renal failure are acute cyclosporine or tacrolimus nephrotoxicity and acute
rejection. Elevated blood levels of cyclosporine or tacrolimus favor nephrotoxicity. Keep in
mind the best time to draws a drug level is 1-3 hours before a dose is scheduled making these
levels unreliable at times in the ED. Renal transplant recipients that present with fever and
allograft tenderness and increased creatinine make acute rejection the likely diagnosis. Urinary
tract infections occur in less than 10% of patients in the first post transplant year and are similar
to that in the general population. Therefore, the most common pathogen to cause urinary tract
infections in renal transplant recipients is E. coli. Remember, to avoid aminoglycosides, a
nephrotoxic agent, when treating urinary tract infections.
Pneumonia is the most common pulmonary issue in renal transplant recipients presenting to the
ED. Non-opportunistic infections occur in the first month post-transplant, followed by
opportunistic infections in the first year and community-acquired respiratory infections
afterward. Macrolides should be avoided in the treatment of pneumonia. The macrolides
inhibit the hepatic enzyme system that metabolizes the immunosuppressants.
Fever in renal transplant patients is a common problem. Immunosuppressed patients are
susceptible to opportunistic infections that can become fulminant, however, they are
uncommon in the first post-transplant month. The highest incidence of opportunistic infections
occurs between the second and sixth month post-transplant. Opportunistic infections vary
geographically, therefore, it is important that ED physicians understand what pathogens are
prevalent in renal transplant patients at their institution and provide appropriate treatment.
Cytomegalovirus (CMV) disease is an opportunistic infection common in renal transplant
patients and with no variation in geographic prevalence. A renal transplant patient presenting 2
months after kidney transplant with high fever, elevated liver function tests and leukopenia
2. likely has CMV disease. CMV is diagnosed with PCR and most commonly presents between one
to six months post transplant. Patients presenting with a fever in the first year after transplant
generally will require admission.
Surgical complications associated with the allograft include acute occlusion of the transplant
renal artery or vein, peritransplant hematoma, urinary leak, lymphocele, obstructive uropathy
and bleeding after renal allograft biopsy. A renal transplant recipient that presents in the first
week post transplant with acute renal failure and oligoanuria likely has acute occlusion of the
transplant renal artery. Peritransplant hematoma occurs as an early postoperative complication
or in perioperative anticoagulation. Patients present with severe pain over the allograft,
decrease in hemoglobin or hematocrit level and an increasing serum creatinine level. Urinary
leak presents in the first post-transplant month and is caused by disruption of the ureteric
anastomosis to the bladder. This leads to extravasation of urine and acute renal failure.
Lymphocele occurs within the first 3 months post-transplant and is caused by severage of the
lymphatics during the transplant operation and leading to a lymph leak. Large lymphoceles can
cause allograft pain, acute renal failure, urinary frequency, ipsilateral lower extremity edema,
iliac vein thrombosis or pulmonary embolism. Causes of obstructive uropathy include technical
problems with ureteric anastomosis or lymphocele which can be followed by stenosis of the
transplanted ureter. Ultrasound can be important to evaluate for fluid collections or
hydronephrosis which may require a nephrostomy tube. Finally, 3% of patients present with
gross hematuria after an allograft biopsy. Severe hematuria may require angiographic occlusion
and blood transfusions. All the allograft complications discussed will require surgical
exploration and interventions as needed.
The risk of cardiovascular disease is threefold to fivefold higher in renal transplant recipients
compared with the general population. If diltiazem, verapamil or amiodarone is used beware of
the immunosuppressive agents, cyclosporine, tacrolimus or sirolimus. The antiarrhythmic
agents inhibit the hepatic P-450 enzyme system, subsequently, elevating the
immunosuppressive levels. Hypertensive urgencies or emergencies can be treated with
parenteral or oral antihypertensives. Gastrointestinal disorders are common and their severity
may be blunted by immunosuppressants, therefore radiologic studies are required. Neurologic
complications can result from side effects of immunosuppressive drugs, opportunistic infections
or malignancy. Headaches in the renal transplant patient warrant a lumbar puncture and
imaging studies of the brain. Anemia, leukopenia and thrombocytopenia may be caused by
immunosuppressants, antibiotics, anti-virals or corticosteroids. Corticosteroids can also cause
osteoporosis, avascular necrosis or tendon rupture affecting the Achilles or quadriceps.
Osteoporosis tends to affect the feet for unclear reasons. Cyclosporine and tacrolimus cause
hyperkalemia and hypomagnesaemia. The above-mentioned immunosuppressants along with
corticosteroids can cause de novo diabetes in 5-20% of renal transplant recipients. Lastly the
3. combination of anemia, thrombocytopenia, and acute renal failure suggests hemolytic uremic
syndrome.
The renal transplant recipient is prone to a number of medical complications. It is important
that emergency physicians understand these medical complexities, including drug regimens and
drug interactions, and make sure to effectively communicate with the transplant physician.
References :-
Review by Jose Vega, MD ( Column Organized by Evan Schwarz, MD of Division of
Emergency Medicine of Washington University )