Biology Reference
In-Depth Information
higher scores in various neuropsychological tests have been recorded. These
findings suggest that anemia may be an important factor in the etiology of ure-
mic brain dysfunction.
Impaired sexual function is common in patients receiving dialysis. Women
may report anovulation, amenorrhea, and infertility,while men may experience
impotence, reduced libido, oligospermia, or gynecomastia. rHuEPO therapy
has been shown to improve libido, potency, and sexual performance in men [26,
27]. Return of regular menstruation and even pregnancy [28] have been report-
ed in women receiving dialysis and rHuEPO. These effects may be partly medi-
ated by changes in prolactin or testosterone concentrations since reductions in
the former and increases in the latter have been found after rHuEPO treatment.
Other diverse endocrine effects that have been reported in association with
rHuEPO include suppressive effects on the renin-angiotensin system, the pitu-
itary-adrenal axis, growth hormone, glucagon, gastrin, follicle-stimulating hor-
mone, and luteinizing hormone, while increases in plasma insulin, parathyroid
hormone, and atrial natriuretic peptide have been reported [29].
Erythropoietin also appears to have effects on the immune system and it has
even been suggested to be a physiologic regulator of immune function.
Concentrations of circulating cytotoxic antibodies progressively decline in
patients receiving rHuEPO therapy [30] and this effect is only partly due to the
avoidance of blood transfusion. Immunoglobulin production and proliferation
of B cells increase, and seroconversion response to hepatitis B vaccination is
enhanced [31]. Phagocytic function in neutrophils is increased [32]. Uremic
pruritus is lessened after commencement of rHuEPO therapy, possibly due to
a reduction in plasma histamine concentrations [33]. The nutritional status of
patients treated with rHuEPO has been shown to improve.
Adverse effects of rHuEPO
Most of the reported complications associated with rHuEPO therapy are
thought to be due not to the recombinant product
per se
but to the resultant
increase in hematocrit and blood viscosity (Tab. 3). Hypertension is the most
common and potentially most worrying adverse effect associated with
Table 3. Adverse effects of recombinant human erythropoietin (rHuEPO) therapy
Hypertension
•
Seizures/encephalopathy
•
ascular access thrombosis
•
Clotting of dialysis lines
•
Hyperkalemia
•
Myalgia/influenza-like symptoms
•
Skin irritation (epoetin alfa only)
•
Pure red cell aplasia (with anti-EPO antibodies)
•
