Rasheed Ahmad

Haemodialysis – Related Porphyria Cutanea Tarda and Treatment by Recombinant Human Erythropoietin

Haemodialysis-related porphyria cutanea tarda is a rare, but serious and mutilating skin condition, resulting from extremely high plasma porphyrin levels because of their inadequate clearance by haemodialysis. The treatment is very difficult as chloroquine is ineffective and venesection, the conventional treatment of this disease, is not always an option because of anaemia of end-stage renal disease. We report a case of haemodialysis-related porphyria cutanea tarda and her successful management by recombinant human erythropoietin treatment.

Resistance to recombinant human erythropoietin due to aluminium overload and its reversal by low dose desferrioxamine therapy.

Seventeen severely anaemic and transfusion-dependent haemodialysis patients with a haemoglobin less than 7 g/dl were treated with recombinant human erythropoietin (r-Hu-EPO). Aluminium toxicity was diagnosed by a positive desferrioxamine (DFO) test and bone biopsy. Seven out of eight patients without aluminium toxicity responded to r-Hu-EPO therapy. Similarly all patients with aluminium toxicity (n = 4) but pre-treated with standard dose of DFO prior to r-Hu-EPO therapy responded but none of the patients with untreated aluminium toxicity (n = 5) responded to r-Hu-EPO therapy. In order to achieve adequate response in these patients, r-Hu-EPO and DFO had to be given in combination. The dose of desferrioxamine used to reverse r-Hu-EPO resistance was less and also used for a short time. We therefore confirm r-Hu-EPO resistance owing to aluminium overload and report its successful and safe reversal with low dose DFO therapy.

Delayed recovery of renal function in patients with acute renal failure due to accelerated hypertension.

Five patients with acute renal failure due to accelerated hypertension required regular dialysis treatment for 2-12 months (mean 8.8), before recovering sufficient renal function for dialysis to be withdrawn. Two patients who had prior evidence of chronic renal impairment remained off dialysis for 20 and 27 months before decompensating again to require regular dialysis treatment. Two patients with no prior history of renal disease have remained independent of dialysis for 32 and 48 months. The fifth patient was lost to follow-up after a 7 month dialysis-free period. Delayed recovery of renal function following accelerated hypertension is a distinct possibility and should be considered in such patients before contemplating long term strategies such as renal transplantation.

Is there a rationale for rationing chronic dialysis? Two points need clarification.

Editor—I agree with Chandna et al that late referral is an important factor in the survival of patients receiving dialysis.1 I am unaware, however, of the source of their information that an NHS consensus statement recommends that nephrology referrals be made at a serum creatinine concentration >135 μmol/l in women and >180 μmol/l in men. The workload generated by this practice would be so enormous that British renal units under present conditions would be unable to cope. I am also concerned that of the authors’ 292 patients receiving dialysis, 26 (admittedly high risk) patients spent 44% of their lives in hospital. The costs of inpatient treatment for these high risk patients would be substantially higher than the average cost of £250 a day that the authors quote.

Profile of serum silicon in aluminium-overloaded patients on regular haemodialysis treatment

Serum concentrations of silicon and aluminium have been compared in patients with end-stage renal disease on haemodialysis treatment. Both serum silicon and aluminium were elevated in comparison with non-renal failure healthy controls and gave an overall significant but relatively weak positive correlation. The silicon concentrations observed however were not related to the duration of the disease or the number of years on dialysis. To investigate a possible chemical interrelationship between the two elements two groups of patients with or without aluminium overload, as determined by a low dose desferrioxamine (DFO) test, were studied. During the DFO test blood samples were taken pre-dialysis then 4, and 48 h after dialysis to establish the effect of dialysis on silicon and aluminium. Serum silicon fell immediately after dialysis whereas aluminium increased in all patients and particularly in the aluminium overload group. Thus, silicon is more freely diffusible than the aluminium–desferal complex and any chemical association between the two individual elements would appear to be relatively weak. However, serum silicon remained significantly higher both before and immediately after dialysis in the aluminium-overload group. The observations indicate that silicon and aluminium show some evidence of association in serum however the exact chemical nature, possibly as an aluminosilicate, needs further investigation.

Grand mal fitting in a patient on regular haemodialysis treatment and receiving desferrioxamine therapy.

Fitting due to aluminium toxicity has been previously reported in chronic dialysis patients with prolonged exposure to aluminium, resulting in excessive aluminium accumulation. However, we report a case of a patient who fitted whilst receiving Desferrioxamine therapy, following a fall with the consequent sudden release of aluminium from fractured ribs. This suggests that sudden increases in serum aluminium levels may carry neurological sequelae.