Icodextrin and skin rash: Unusual presentation.

We report a case of 50-year-old woman who was on continuous cyclic peritoneal dialysis (PD) with glucose exchanges. Her PD prescription was recently modified with an add-on last fill of icodextrin 7.5%. Four weeks later, she returned with generalized erythematous, itchy, maculopapular rash over the trunk and the back [Figures 1 and 2]. Laboratory results showed no signs of infection or inflammation. There was no other recent change in her diet and medications or a history of allergy or a skin disorder. Icodextrin was discontinued in view of chronology of this adverse reaction. In next 2 weeks, her rash disappeared. A similar presentation was seen in another woman who came with a similar presentation of rash, although seven weeks after icodextrin initiation and who also responded to stoppage of icodextrin. Furthermore, we found that both these patients had same lot number of icodextrin supplies. We, however, did not rechallenge our patients with icodextrin as it was neither ethically justified nor clinically indicated in absolute terms.

Figure 1

Photograph showing maculopapular rash over the trunk

Figure 2

Photograph showing maculopapular rash over the back

Icodextrin-based therapies have 10.1% incidence of rash compared with glucose regimes (4.6%, P value <0.003).[1] Our cases were unusual in two aspects. Rash were late-onset, whereas in most reports, rash occurred early within 3 weeks of icodextrin initiation.[1] Secondly, the rash generally involves palms and soles[1] which was spared in our cases.

The pathophysiology of cutaneous hypersensitivity to icodextrin is still unknown. It may be postulated that as icodextrin is constantly absorbed from lymphatics, it can induce immunosensitization. This maculopapular rash could be a distant manifestation of peritoneal immune process. Maltose, a metabolite of icodextrin, has a structural homology with dextran which is shown to cause nerve stimulation and pruritis in chronically exposed individuals.[2] The two polymers differ in their linkage of glucose molecules, α- 1,4 for icodextrin and α-1,6 for dextran. Dextran antibodies have been reported in PD patients.[3]

Though icodextrin is safe, it must be recognized as the possible cause of cutaneous hypersensitivity reactions. Nephrologists and dermatologists should be aware of this potential complication. A search for the icodextrin epitope causing this hypersensitivity should end the mystery.