Sinnamon_edit.qxp 8/2/08 10:12 Page 31
Anaemia Management
Anaemia Following Renal Transplantation
a report by
Kim Sinnamon
Consultant Nephrologist, Colchester General Hospital
Although the majority of renal allografts work well following exogenous erythropoietin. This was consistent with the findings of
transplantation, they do not function optimally, which would entail the Winkelmayer and colleagues, who noted that only 41.6% of their
glomerular filtration rate (GFR) being consistently lower than the transplant population with an HCT <30% received an erythropoiesis-
physiological gender-matched normal range for a person with a single stimulating agent.
11
In the TRESAM study,
7
just 17.8% of those with
kidney. Renal transplant recipients are therefore vulnerable to the same severe anaemia (males Hb <11g/dl, females Hb <10g/dl) were receiving
haematological and biochemical abnormalities associated with a erythropoietin therapy.
reduced GFR as are other patients with chronic renal impairment. Until
recently, anaemia following renal transplantation was an under- Risk Factors
recognised issue as the focus was placed primarily on the prevention of Anaemia following renal transplantation is multifactorial in aetiology. In
rejection and the attainment of good graft function. With advances in the early post-transplant period (first six months), peri-operative blood
transplant management such as the advent of newer immuno- loss, bone marrow suppression from medications or viruses and rejection
suppressive regimens, graft and patient survival rates continue to episodes are likely to play a role. In the longer term, immunosuppressants
improve. As the most common cause of allograft loss is recipient death, and chronic renal impairment may be causative.
predominately due to cardiovascular disease,
1
the need to address
cardiovascular risk factors in these patients is receiving more attention Graft Function
from the transplant community. Anaemia following renal One of the main influences on the development of PTA is the degree of
transplantation is a significant risk factor for left ventricular hypertrophy
2
renal dysfunction. The TRESAM study
7
demonstrated a strong
and de novo congestive heart failure,
3
and is associated with inferior association between Hb and graft function: in patients with a serum
patient survival and a higher proportion of cardiovascular deaths.
4
Thus, creatinine level >2mg/l (>176mmol/l), 60% were anaemic compared
recognition and adequate management of post-transplantation anaemia with 29% of those with a serum creatinine level <2mg/l (p<0.01).
(PTA) is an important issue. Winkelmayer and co-workers
11
studied 374 renal transplant recipients
and found that kidney function was independently associated with
Prevalence anaemia (defined as HCT <33%). Compared with patients with a serum
Due to heterogeneity in the definition of PTA used in the literature, it is creatinine level of <1.5mg/dl (<132mmol/l), those whose creatinine was
difficult to make valid comparisons between studies; this contributes to 1.5–2mg/dl (132–176mmol/l), 2–3mg/dl (176–264mmol/l) and >3mg/dl
the variation between results. The reported prevalence of PTA is (>264mmol/l) had an HCT value that was lower by approximately
approximately 20–40%.
5–13
One of the largest studies in this area is the 1.47, 2.75 and 7.25%, respectively. Yorgin and colleagues
6
noted
Transplant European Study on Anemia Management (TRESAM) survey.
7
that anaemic patients were more likely to have a creatinine clearance
Data on 4,263 patients (62% males) from 72 centres in 16 countries who of <50ml/min/1.73m
2
than non-anaemic patients: 51 and 15%,
had received renal transplants six months to five years earlier were respectively. Similar associations between anaemia and graft function
collected retrospectively. The mean age of the recipients was 45.5 years have been noted in other studies.
10,12,14,15
at transplantation; chronic glomerulonephritis was the most common
aetiology of end-stage renal disease. Anaemia was defined as However, anaemia is not invariably associated with poor renal function,
haemoglobin (Hb) levels ≤13g/dl for males and ≤12g/dl for females. At implying that other factors are influential. In the study by Yorgin and
enrolment, 38.6% of patients were anaemic. co-workers
6
there were anaemic patients with a creatinine clearance
>75ml/min/1.73m
2
, as well as those who did not have anaemia but had
A similar prevalence of PTA has been reported elsewhere. Yorgin and poor renal function. An Australian study by Chadban and colleagues
16
colleagues conducted a retrospective analysis of 128 renal transplant
recipients who were transplanted at a single centre.
6
Data were collected
Kim Sinnamon is a Consultant Nephrologist at Colchester
at zero, one, two, three, four and five years following engraftment.
General Hospital. She is a member of the Royal College of
Anaemia was defined as a haematocrit (HCT) <33 volume percentage. By
Physicians and is certified in nephrology. Dr Sinnamon
five years after transplantation, 26% of the patients were anaemic. Mix
studied medicine at Queens University Belfast and graduated
in 2000, before undertaking specialist registrar training in
and co-workers defined anaemia as an HCT <36% and found that 76% Northern Ireland, which she completed in August 2007. She
of their patients at the time of transplantation, 21% one year later and
is working towards a Masters degree in medical education
for the healthcare professions.
36% after four years were anaemic.
10
Despite laboratory evidence of
significant anaemia (HCT <30%), only 36% had iron studies performed,
E: kimsinnamon@msn.com
46% had received iron supplementation and 40% had received
© TOUCH BRIEFINGS 2007 31