Cutaneous abnormalities and metabolic disturbance of porphyrins in patients on maintenance haemodialysis

Pseudoporphyria: An Atypical Variant Resembling Toxic Epidermal Necrolysis

Background:

Pseudoporphyria has been attributed to both medication usage and chronic hemodialysis. Histologically, it is identical to porphyria cutanea tarda. It is most commonly seen as localized bullae on sun-exposed skin, often on the dorsum of the hands and fingers.

Objectives:

We describe a 31-year-old man with rapidly evolving bullae which became denuded, clinically suggestive of toxic epidermal necrolysis. Pseudoporphyria was proven histologically. However, our patient's eruption was not localized as small bullae but was widespread, with large bullae evolving into large, cutaneous, denuded erosions.

Conclusions:

We describe a previously unreported, generalized variant of pseudoporphyria that resembles toxic epidermal necrolysis. We provide a review of pseudoporphyria and compare our variant to toxic epidermal necrolysis and mimicking disorders.

Unusual palmoplantar blistering in the setting of hemodialysis: a case report and review of the dermatoses associated with hemodialysis

We describe a 70-year-old White female on maintenance high-flux hemodialysis for chronic renal insufficiency with an abrupt onset of asymptomatic palmoplantar blisters. The lesions were tense, noninflamed and 0.2-1.0 cm in dimension. Concomitant photo-distributed blistering of the dorsal hands and forearms was not present. A cutaneous biopsy demonstrated nonspecific histological and direct immunofluorescent findings. Serum indirect immunofluorescence and tissue cultures for bacteria, fungi and viruses were negative. Fecal porphyrins were normal but an elevated plasma uroporphyrin level of 17.0 microg/dL (normal: < 1.0 microg/dL) was observed. The duration of each hemodialysis treatment, which the patient had continued to receive three times per week, was changed from 2 to 2.5 h. Within 2 weeks no new blisters occurred. Within 6 weeks complete clinical and biochemical remission was noted. During this time course no topical steroid or antifungal therapy was employed nor was the patient's oral medication regimen altered.

[Porphyria cutanea tarda in a dialyzed female patient]

Dermatological disorders are a frequent finding in patients with renal insufficiency. Porphyria cutanea tarda, pseudoporphyria, phototoxicity or concurrent bullous diseases may cause the appearance of lesions with liquid content in patients in dialysis. We describe the case of a female patient in dialysis who developed bullous lesions. The clinical and laboratory findings were initially compatible with the suspicion of pseudoporphyria, but the finding of some frankly elevated levels of porphyrins in serum, urine and feces confirmed the diagnosis of porphyria cutanea tarda. Porphyria cutanea tarda and pseudoporphyria present with common clinical manifestations. However, the levels of porphyrins in plasma, urine and feces in pseudoporphyria are normal or slightly elevated.

Porphyrie cutanée tardive chez un hémodialysé ayant une hépatite virale C : efficacité du traitement par petites phlébotomies

INTRODUCTION

Porphyria cutanea tarda (PCT) is a disorder of heme biosynthesis resulting from deficiency in the enzyme uroporphyrinogen decarboxylase. In the sporadic form of PCT, there are many agents that trigger the clinical manifestations.

EXEGESIS

We report a case of PCT in an hemodialysed patient with hepatitis C virus infection (HVC). He was treated with small repeated phlebotomies of 50 ml every week with photoprotection, eviction of traumatismes and inducing drugs. A clinical remission was induced after five months of treatment.

CONCLUSION

A proper diagnosis of PCT in non uremic hemodialysed patients requires fractionation of serum and fecal porphyrin changes. Management of this patients is difficult. Small repeated phlebotomies (50-100 ml) could be an interesting therapy.

Porphyria cutanea tarda

Porphyria cutanea tarda (PCT) is a metabolic disorder of haem biosynthesis caused by decreased activity of uroporphyrinogen decarboxylase. Porphyria cutanea tarda is manifest by fragility, erosions, bullae, milia and scars on sun-exposed skin. Excess porphyrins in the skin interact with light of approximately 400 nm-wavelength radiant energy, forming reactive oxygen species. Porphyria cutanea tarda is categorized as familial, acquired or toxic. Factors that may induce clinical expression of PCT in susceptible individuals include alcohol, oestrogen, iron, polyhalogenated compounds and viral infections. Porphyria cutanea tarda is associated with an increased incidence of the haemochromatosis gene. Treatments for PCT include withdrawal of aggravating factors, phlebotomy and oral antimalarial medications.

Bullous dermatoses in end-stage renal failure: porphyria or pseudoporphyria?

Bullous dermatoses (BD) are well recognized in patients with end-stage renal disease (ESRD). It is important to distinguish pseudoporphyria (porphyrin accumulation due to decreased clearance) from true porphyrias, particularly those in which acute neurological attacks may occur. Investigation of the dialysis patient poses practical diagnostic difficulties because urinary porphyrin profiles are not available. We describe a patient on continuous ambulatory peritoneal dialysis (CAPD) with several recognized causative factors for porphyria cutanea tarda (PCT). The patient presented with a blistering photosensitive rash. We highlight the importance of investigating anuric patients with fractionation of both fecal and plasma porphyrins. Plasma porphyrins were grossly elevated (345 nmol/L; reference range, <13), whereas plasma porphyrins in a control group of CAPD patients without blistering rashes were only minimally elevated (mean, 23.9 nmol/L; SD, 11.0; n = 9). Fractionation of fecal porphyrins by high-performance liquid chromatography (HPLC) yielded a pattern typical of PCT. In addition to the contributory factors for PCT that were present, it is possible that porphyrin accumulation secondary to renal failure played a role in the expression of her disease. Patients with ESRD presenting with BD require careful evaluation, including fractionation of fecal porphyrins.