Pseudoporphyria

Clinical Characteristics and Inciting Agents for Pseudoporphyria: The Mayo Clinic Experience, 1996-2020

GENERAL PURPOSE

To raise awareness regarding the clinical presentations of patients with pseudoporphyria.

TARGET AUDIENCE

This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and registered nurses with an interest in skin and wound care.

LEARNING OBJECTIVES/OUTCOMES

After participating in this educational activity, the participant will:1. Describe the clinical presentation of pseudoporphyria.2. Identify the differential diagnoses of blistering lesions on hands and feet.3. Outline the management options for patients with porphyria.

Practical recommendations for biochemical and genetic diagnosis of the porphyrias

The porphyrias are a group of rare inborn errors of metabolism associated with various clinical presentations and long-term complications, making them relevant differential diagnoses to consider for many clinical specialities, especially hepatologists, gastroenterologists and dermatologists. To diagnose a patient with porphyria requires appropriate biochemical investigations, as clinical features alone are not specific enough. Furthermore, it is important to be aware that abnormalities of porphyrin accumulation and excretion occur in many other disorders that are collectively far more common than the porphyrias. In this review, we provide an overview of porphyria-related tests with their strengths and limitations, give recommendations on requesting and diagnostic approaches in non-expert and expert laboratories for different clinical scenarios and discuss the role of genetic testing in the porphyrias. To diagnose porphyria in a currently symptomatic patient requires analysis of biochemical markers to demonstrate typical patterns of haem precursors in urine, faeces and blood. The use of genomic sequencing in diagnostic pathways for porphyrias requires careful consideration, and the demonstration of increased porphyrin-related markers is necessary prior to genomic testing in symptomatic patients. In the acute porphyrias, genomic testing is presently a useful adjunct for genetic counselling of asymptomatic family members and the most common cutaneous porphyria, porphyria cutanea tarda, is usually a sporadic, non-hereditary disease. Getting a correct and timely porphyria diagnosis is essential for delivering appropriate care and ensuring best patient outcome.

Drug-Induced Pseudoporphyria: A Case Report

Pseudoporphyria is an uncommon dermatosis resembling porphyria cutanea tarda (PCT). The exclusion of true porphyria, especially PCT, is critically essential for diagnosing pseudoporphyria. It has an unknown underlying pathophysiology with a normal or near-normal porphyrin profile. Pseudoporphyria has been associated with chronic renal failure and hemodialysis, medications, and tanning beds. In drug-induced pseudoporphyria cases, eliminating the suspected photosensitizing drug improves the disease typically within weeks to months (on average eight weeks). In genetically predisposed individuals, phototoxic metabolites may trigger the development of skin fragility, bullae, milia, and scarring on the dorsum of the hands and other sun-exposed areas. Wearing a broad-spectrum sunscreen and maintaining strict ultraviolet protection is essential in cases of pseudoporphyria. We report the case of a 20-year-old male who presented to us with complaints of photosensitivity and multiple erosions with irregular scars over photo-exposed areas involving the dorsum of the hands and face predominantly. The patient was evaluated further to determine the underlying cause. A wood's lamp examination of the urine was done, which did not show fluorescence. Based on clinical and laboratory findings, the diagnosis of pseudoporphyria was made, and the patient was started on the oral antimalarial agent hydroxychloroquine sulfate with strict sun protection.

Dermatological Manifestations in Patients With Chronic Kidney Disease: A Review

Chronic kidney disease (CKD) is a progressive disease and has multiple clinical manifestations; when CKD reaches the end stage, at least one cutaneous manifestation appears due to some increased toxin levels or a constant proinflammatory state. Nonspecific manifestations include pruritus, xerosis, pigmentation disorders, acquired ichthyosis, purpuric spots, and nail disorders. Some specific manifestations are bullous dermatoses, acquired perforating dermatoses (APD), eruptive xanthoma, access site infections, calcifying disorders, and nephrogenic systemic fibrosis (NSF). All these cutaneous changes negatively impact patients; early recognition and diagnosis of these dermatoses will make a difference in their quality of treatment. Exploring a patient's skin is fundamental to suspect some diseases and increased toxin levels; pruritus occurs when uremic toxins are raised, and nail disorders are associated with hypoalbuminemia. This review provides the clinician with information on the clinical manifestations that occur in CKD, including epidemiology, pathophysiology, clinical manifestations, diagnosis, histopathology, treatment, and life impact of the dermatoses in CKD.

The role of eosinophils in the differential diagnosis of inflammatory skin diseases

Eosinophils are known to be present in inflammatory skin diseases, but their diagnostic utility is not well established. Upon review of the published status of lesional eosinophils, several categories were identified. 1) Lesional eosinophils highly characteristic such that, in their absence, the pathologist may question the diagnosis. These include arthropod bite reactions and scabies, urticarial dermatitis, and other eosinophilic dermatoses. 2) Lesional eosinophils rare or absent, such that, in their presence, the pathologist may question the diagnosis. These include pityriasis lichenoides, graft versus host disease, and connective tissue disorders. 3) Lesional eosinophils variable and, while in some cases expected, are not required for diagnosis. These include drug reactions, atopic dermatitis and allergic contact dermatitis. 4) Lesional eosinophils variable and not expected but may be seen to a limited extent. These include lichen planus and psoriasis.

Plasma porphyrins among end stage renal disease patients and cutaneous symptoms- is there still an association?

Introduction

Several abnormalities of porphyrin metabolism leading to Porphyria Cutanea Tarda (PCT) have been described in early studies of End Stage Renal Disease (ESRD) patients, with a reported prevalence of 5-18%. We aimed to evaluate porphyrin levels and correlation to skin manifestations in modern dialysis era.

Methods

The study cohort included adult hemodialysis patients from a single center tertiary medical center. All patients underwent a full skin examination, completed the Dermatology Life Quality Index questioner, and provided a blood sample for porphyrin levels assessment.

Results

A total of 94 adult hemodialysis patients were recruited to the study. No clinical PCT was diagnosed. Porphyrin levels did not correlate with any clinical or dialysis quality parameters.

Conclusions

In modern hemodialysis era, possibly due to improved porphyrins' metabolism and dialysis removal, PCT is much less prevalent among hemodialysis patients than previously reported in the past.

Renal Transplantation Could Reverse Dialysis-Associated Porphyria

Pseudoporphyria (PP) is a relatively infrequent, photodistributed bullous dermatosis that clinically, histopathologically, and immunologically resembles porphyria cutanea tarda (PCT), but is not accompanied by porphyrin abnormalities in the serum, urine, or stool. It was initially described in patients with renal failure on dialysis as 'bullous dermatosis of hemodialysis.' Pseudoporphyria has been seen in patients with end-stage renal disease on hemodialysis. No treatment has proved efficacious in the management of pseudoporphyria. However, N-acetylcysteine has been anecdotally reported to be effective in the management of hemodialysis-related pseudoporphyria and other porphyric diseases. Our patient had developed multiple skin lesions all over the body when hemodialysis started. The lesions were erythematous with fluid-filled vesicles, and bullae with cutaneous fragility that were evaluated and diagnosed as pseudoporphyria. The patient was treated with available all medication in the literature but was not relieved. However, all skin lesions completely healed within 22 days post renal transplantation. Renal transplantation proved to be the cure for dialysis-induced pseudoporphyria resistant to conventional drug therapy.

Drug-Induced Photosensitivity: Clinical Types of Phototoxicity and Photoallergy and Pathogenetic Mechanisms

Drug-induced photosensitivity (DIP) is a common cutaneous adverse drug reaction, resulting from the interaction of ultraviolet radiations, mostly ultraviolet A, with drugs. DIP includes phototoxicity and photoallergy. A phototoxic reaction is obtained when topical and systemic drugs or their metabolites absorb light inducing a direct cellular damage, while a photoallergic reaction takes place when the interaction between drugs and ultraviolet radiations causes an immune cutaneous response. Clinically, phototoxicity is immediate and appears as an exaggerated sunburn, whereas photoallergy is a delayed eczematous reaction. DIP may show several clinical subtypes. In this mini-review we report the pathogenetic mechanisms and causative drugs of DIP. We offer a detailed description of DIP clinical features in its classical and unusual subtypes, such as hyperpigmentation/dyschromia, pseudoporphyria, photo-onycolysis, eruptive teleangiectasia, pellagra-like reaction, lichenoid reaction, photodistributed erythema multiforme and subacute/chronic cutaneous lupus erythematosus. We described how physicians may early recognize and manage DIP, including diagnostic tests to rule out similar conditions. We made suggestions on how to improve sun exposure behaviors of patients at risk of DIP by means of an aware use of sunscreens, protective clothing and recent technologic tools. We highlighted the lack of sun safety programs addressed to patients at risk of DIP, who need a formal education about their condition.

Drug-Induced Photosensitivity-From Light and Chemistry to Biological Reactions and Clinical Symptoms

Photosensitivity is one of the most common cutaneous adverse drug reactions. There are two types of drug-induced photosensitivity: photoallergy and phototoxicity. Currently, the number of photosensitization cases is constantly increasing due to excessive exposure to sunlight, the aesthetic value of a tan, and the increasing number of photosensitizing substances in food, dietary supplements, and pharmaceutical and cosmetic products. The risk of photosensitivity reactions relates to several hundred externally and systemically administered drugs, including nonsteroidal anti-inflammatory, cardiovascular, psychotropic, antimicrobial, antihyperlipidemic, and antineoplastic drugs. Photosensitivity reactions often lead to hospitalization, additional treatment, medical management, decrease in patient's comfort, and the limitations of drug usage. Mechanisms of drug-induced photosensitivity are complex and are observed at a cellular, molecular, and biochemical level. Photoexcitation and photoconversion of drugs trigger multidirectional biological reactions, including oxidative stress, inflammation, and changes in melanin synthesis. These effects contribute to the appearance of the following symptoms: erythema, swelling, blisters, exudation, peeling, burning, itching, and hyperpigmentation of the skin. This article reviews in detail the chemical and biological basis of drug-induced photosensitivity. The following factors are considered: the chemical properties, the influence of individual ranges of sunlight, the presence of melanin biopolymers, and the defense mechanisms of particular types of tested cells.

PLASMA VORICONAZOLE CONCENTRATIONS FOLLOWING SINGLE- AND MULTIPLE-DOSE SUBCUTANEOUS INJECTIONS IN WESTERN POND TURTLES (ACTINEMYS MARMORATA)

A recently characterized fungal pathogen, Emydomyces testavorans, has been associated with ulcerative shell disease and significant morbidity in Western pond turtles. Voriconazole is a second-generation triazole antifungal medication that prevents fungal growth through disruption of ergosterol synthesis, causing abnormalities in the fungal cell membrane. Preliminary reports of minimum inhibitory concentrations (MIC) indicate that voriconazole is effective in vitro against E. testavorans. Ultraperformance liquid chromatography was used to measure voriconazole plasma concentrations in blood samples from healthy Western pond turtles after administration of a single SC injection of 10 mg/kg and after multiple doses (10 mg/kg SC q48h for seven doses). The data were analyzed using a naïve pooled approach. Mean (SE) observed time to maximum concentration was 2 (0.18) h for a single dose and 50 (2.2) h for multiple doses; the multiple-dose trial observed mean (SE) maximum concentration was 12.4 (2.2) µg/ml, and observed mean (SE) trough concentration was 1.7 (0.7) µg/ml. Multifocal skin sloughing following the single-dose trial was observed in one turtle and there was a significant increase in polychromatophilic cells amongst the study turtles after the multiple-dose voriconazole trial. No other adverse effects were observed. When voriconazole was administered at 10 mg/kg SC q48h, observed trough plasma concentrations were consistently higher than reported E. testavorans MIC concentrations. Further study is needed to determine the clinical safety and in vivo efficacy of this dose in Western pond turtles.

Kidney transplantation improves the clinical outcomes of Acute Intermittent Porphyria

BACKGROUND

Acute Intermittent Porphyria (AIP) is a rare inherited autosomal dominant disorder of heme biosynthesis. Porphyria-associated kidney disease occurs in more than 50% of the patients with AIP, and end stage renal disease (ESRD) can be a devastating complication for AIP patients. The outcomes of AIP patients after kidney transplantation are poorly known.

METHODS

We examined the outcomes of 11 individuals with AIP, identified as kidney transplant recipients in the French Porphyria Center Registry.

RESULTS

AIP had been diagnosed on average 19 years before the diagnosis of ESRD except for one patient in whom the diagnosis of AIP had been made 5 years after the initiation of dialysis. Median follow-up after transplantation was 9 years. A patient died 2 months after transplantation from a cardiac arrest and a patient who received a donation after cardiac death experienced a primary non-function. No rejection episode and no noticeable adverse event occurred after transplantation. Serum creatinine was on average 117 μmol/l, and proteinuria <0.5 g/l in all patients at last follow up. All usually prescribed drugs after transplantation are authorized except for trimethoprim/sulfamethoxazole. Critically, acute porphyria attacks almost disappeared after kidney transplantation, and skin lesions resolved in all patients.

CONCLUSION

Kidney transplantation is the treatment of choice for AIP patients with ESRD and dramatically reduces the disease activity.

An unusual bullous eruption: olanzapine induced pseudoporphyria

A 27-year-old man with a background of schizophrenia presented during the summer months with a 2-day history of a blistering eruption predominantly affecting his hands, forearms and face. He had not knowingly been exposed to any chemicals or toxins and was otherwise well. Clinical examination revealed multiple, large, tense blisters affecting the sun-exposed sites. Histology subsequently demonstrated subepidermal blisters with minimal inflammation and negative immunofluorescence. Porphyrin biochemistry including faecal, urinary and serum samples were unremarkable and thus a diagnosis of pseudoporphyria was reached. There were no obvious triggers, however, olanzapine (an atypical antipsychotic) had been commenced 2 months previously and was deemed to be the most likely cause. This is the first report of pseudoporphyria being associated with an atypical antipsychotic and highlights the importance of eliciting an accurate drug history by specifically enquiring about any recent medication changes that could account for the clinical presentation.

Sporadic Porphyria Cutanea Tarda as the Initial Manifestation of Hereditary Hemochromatosis

Porphyria cutanea tarda (PCT) is a skin disorder characterized by abnormal heme synthesis. We present a 45-year-old man with intermittent skin lesions recurring annually for years. Skin biopsy and measurement of serum heme precursors confirmed a diagnosis of PCT. He had persistently elevated alanine and aspartate transferase. He was referred to hematology and had genetic testing with iron studies which also revealed hereditary hemochromatosis (HH). Therapeutic phlebotomy was initiated, which led to resolution of iron overload and skin lesions. We highlight the associated conditions of PCT and HH, their common therapy of phlebotomy, and initial manifestations of HH.

[The cutaneous porphyrias]

The porphyrias are a group of metabolic disorders resulting from an innate abnormality in haem biosynthesis, and the clinical settings of which vary according to the genetic enzyme abnormality in question. These are genetic disorders with autosomal dominant or recessive inheritance of varying penetrance, and whose clinical expression differs according to the preferential location of haem precursors. Different classifications have been proposed according to genetic inheritance, the enzyme anomaly at issue, and clinical expression. The clinical classification distinguishes between acute porphyria (acute intermittent porphyria, porphyria variegata, hereditary coproporphyria), bullous cutaneous porphyrias (porphyria cutanea tarda, porphyria variegata and hereditary coproporphyria), painful photosensitive acute cutaneous porphyrias (erythropoietic protoporphyria and X-linked dominant protoporphyria), and rare recessive porphyrias (congenital erythropoietic porphyria, Doss porphyria, hepatoerythropoietic porphyria and harderoporphyria). Treatment depends on the clinical expression of the disorder.

Furosemide-induced pseudoporphyria in a patient with chronic kidney disease: case report

Introduction:

Pseudoporphyria is a rare photodermatosis with characteristics similar to those of porphyria cutanea tarda, without, however, presenting abnormalities in porphyrin metabolism. Its etiology is related to chronic kidney disease, ultraviolet radiation and certain medications. The aim of the present study is to describe a case of furosemide-related pseudoporphyria in a patient with chronic kidney disease.

Case description:

A 76-year-old male patient with stage 4 chronic kidney disease and in continuous use of furosemide presented ulcerated lesions with peripheral erythema and central hematic crust in the legs. On a skin infection suspicion, treatment with quinolone and neomycin sulfate was initiated, without improvement. A biopsy of the lesion was performed, with histopathological examination demonstrating findings compatible with porphyria, although the patient did not present high porphyrin levels. The diagnosis of furosemide-induced pseudoporphyria was then established, with medication suspension, and there was a significant improvement of the lesions.

Discussion:

There are few cases of pseudoporphyria described, but it is believed that this condition is underdiagnosed, especially in patients with chronic kidney disease. Both clinical and histopathological findings closely resemble porphyria, differentiating it from normal levels of porphyrin in plasma, urine, or feces.

Conclusions:

Although the lesions are mostly benign, they may increase the morbidity and mortality of these patients, so a proper diagnosis and early treatment are extremely important.

Porphyria and kidney diseases

The kidneys, after the bone marrow and liver, are third in terms of the amounts of haem synthesized daily. Haem is incorporated into haemoproteins that are critical to renal physiology. In turn, disturbances in haem metabolism interfere with renal physiology and are tightly interrelated with kidney diseases. Acute intermittent porphyria causes kidney injury, whereas medical situations associated with end-stage renal disease, such as porphyrin accumulation, iron overload and hepatitis C, participate in the inhibition of uroporphyrinogen decarboxylase and predispose the individual to porphyria cutanea tarda. Even if some of these interactions have been known for a long time, the clinical situations associated with these interrelations have strikingly evolved over time with the advent of new therapeutic strategies for dialysis therapy and a better understanding of the pathophysiological mechanisms of porphyria-associated kidney disease. Physicians should be aware of these interactions. The aim of this review is to summarize the complex interactions between kidney physiology and pathology in the settings of porphyria and to emphasize their often-underestimated importance.

Porphyria cutanea tarda: an intriguing genetic disease and marker

Porphyrias are a group of intriguing genetic diseases of the heme pathway, of which porphyria cutanea tarda (PCT) is the most common. Resulting from a defect in enzymes in the porphyria pathway, PCT has been linked to several conditions. Recent studies have demonstrated a change in thinking regarding the human immunodeficiency virus (HIV) and development of PCT. The exacerbation of PCT with contraction of HIV is now believed to result from coinfection from the hepatitis C virus (HCV). Blistering of sun-exposed skin, a classic presenting sign of PCT, is not exclusive to the condition. Cutaneous findings must also trigger physicians to consider additional types of porphyrias, such as variegate porphyria. The diagnosis of pseudoporphyria, which does not result from enzymatic absence, must be considered in patients with photosensitivity and cutaneous bullae. Recent health food trends, such as chlorophyll, have been linked to pseudoporphyria. PCT is a serious condition in which accurate diagnosis is necessary for appropriate management.

Best practice guidelines on first-line laboratory testing for porphyria

The porphyrias are disorders of haem biosynthesis which present with acute neurovisceral attacks or disorders of sun-exposed skin. Acute attacks occur mainly in adults and comprise severe abdominal pain, nausea, vomiting, autonomic disturbance, central nervous system involvement and peripheral motor neuropathy. Cutaneous porphyrias can be acute or chronic presenting at various ages. Timely diagnosis depends on clinical suspicion leading to referral of appropriate samples for screening by reliable biochemical methods. All samples should be protected from light.

Investigation for an acute attack:

• Porphobilinogen (PBG) quantitation in a random urine sample collected during symptoms. Urine concentration must be assessed by measuring creatinine, and a repeat requested if urine creatinine <2 mmol/L.

• Urgent porphobilinogen testing should be available within 24 h of sample receipt at the local laboratory. Urine porphyrin excretion (TUP) should subsequently be measured on this urine.

• Urine porphobilinogen should be measured using a validated quantitative ion-exchange resin-based method or LC-MS.

• Increased urine porphobilinogen excretion requires confirmatory testing and clinical advice from the National Acute Porphyria Service.

• Identification of individual acute porphyrias requires analysis of urine, plasma and faecal porphyrins.

Investigation for cutaneous porphyria:

• An EDTA blood sample for plasma porphyrin fluorescence emission spectroscopy and random urine sample for TUP.

• Whole blood for porphyrin analysis is essential to identify protoporphyria.

• Faeces need only be collected, if first-line tests are positive or if clinical symptoms persist.

Investigation for latent porphyria or family history:

• Contact a specialist porphyria laboratory for advice. Clinical, family details are usually required.

Adverse Medication Reactions

Cutaneous adverse drug reactions (ADRs) are among the most frequent adverse reactions in patients receiving drug therapy. They have a broad spectrum of clinical manifestations, are caused by various drugs, and result from different pathophysiological mechanisms. Hence, their diagnosis and management is challenging.

Severe cutaneous ADRs comprise a group of diseases with major morbidity and mortality, reaching 30 % mortality rate in cases of Toxic Epidermal Necrolysis.

This chapter covers the terminology, epidemiology, pathogenesis and classification of cutaneous ADR, describes the severe cutaneous ADRs and the clinical and laboratory approach to the patient with cutaneous ADR and presents the translation of laboratory-based discoveries on the genetic predisposition and pathogenesis of cutaneous ADRs to clinical management guidelines.

Nonsteroidal Antiinflammatory Drug-Induced Pseudoporphyria: A Case Series

Background:

Pseudoporphyria is a diagnosis that is used when porphyria-like clinical lesions arise in the setting of normal porphyrin levels. This condition was first described in the 1960s and was initially related to the use of certain antibiotic drugs. In 1985, pseudoporphyria was first attributed to the use of nonsteroidal antiinflammatory drugs (NSAIDs). Subsequently, a host of NSAIDs and other drugs have been found to elicit the same clinical entity. The exact mechanism by which certain drugs create clinical lesions resembling porphyria cutanea tarda or erythropoietic protoporphyria is still unknown. A phototoxic mechanism is hypothesized.

Objective:

We describe six patients diagnosed with pseudoporphyria and detail the diagnostic tests leading to the eventual diagnosis.

Results:

The patients ranged in age from 27 to 59 years and had a female:male predominance of 2:1. The offending NSAID was DayPro (oxaprozin) for three of the patients, Relafen (nabumetone) for two of the patients, and Aleve (naproxen) for one patient. For each patient, histology and immunofluorescence was either consistent with the diagnosis of porphyria cutanea tarda or nonspecific, while serum, stool, and urine porphyrins did not support that diagnosis. Withdrawal of the offending agent provided relief from the clinical symptoms for each patient. None of our patients were rechallenged with the putative offending drug. However, prolonged avoidance has provided a sustained remission from symptoms in all six patients.

Conclusions:

Pseudoporphyria is a relatively rarely reported condition. Clinical suspicion with appropriate laboratory and histopathologic findings help to make this diagnosis, and exclude true porphyrias. Rechallenge with the offending drug to produce symptom relapse has been proposed to be helpful in confirming this diagnosis of exclusion. Since all 6 patients with drug-induced pseudoporphyria experienced resolution of their symptoms after discontinuing the offending agent, we propose that this clinical correlation alone is sufficient to confirm this diagnosis. Our observation of six new cases of NSAID-induced pseudoporphyria over a two-year interval suggests that this is not a rare entity.

Drug-induced photosensitivity: Photoallergic and phototoxic reactions

Drug-induced photosensitivity refers to the development of cutaneous disease due to the interaction between a given chemical agent and sunlight. Photosensitivity reactions can be classified as phototoxic or photoallergic. Sometimes, there is an overlap between these two patterns, making their distinction particularly difficult for the clinician. We review the drugs that have been implicated as photosensitizers, the involved mechanism, and their clinical presentations. The main topical agents that cause contact photosensitivity are the nonsteroidal antiinflammatory drugs, whereas the main systemic drugs inducing photosensitivity are antimicrobials, nonsteroidal antiinflammatory agents, and cardiovascular drugs. Drug-induced photosensitivity remains a common clinical problem and is often underdiagnosed.

Drug induced pseudoporphyria in CKD: A case report

Pseudoporphyria (PP) is used to describe a photodistributed bullous disorder with clinical and histologic features of porphyria cutanea tarda (PCT) but without accompanying biochemical porphyrin abnormalities. Medications, excessive sun and ultraviolet radiation exposure, have all been reported to develop PP. We report a case of PP in a 49-year-old man with CKD stage 3a, caused due to torsemide intake. This is probably the first reported case of PP developing in a dialysis naive patient CKD due to torsemide intake from India.

Cutaneous abnormalities in patients with end stage renal failure on chronic hemodialysis. A study of 458 patients

BACKGROUND

Cutaneous manifestations occurring in patients with end stage renal failure on hemodialysis are polymorphic and diverse.

OBJECTIVE

The aim of our study was to assess the prevalence and characteristics of different cutaneous manifestations in patients on hemodialysis.

PATIENTS AND METHODS

We led a transverse investigation of all patients on hemodialysis in 12 haemodialysis centres of Sfax (Tunisia). We examined 458 patients (254 men and 204 women). The hemodialysis history ranged from 6 months to 24 years. A total of 394/458 (86%) patients had cutaneous abnormalities. These included pruritus (56.6% of patients), paleness (60.7%), xerosis (52.8%), hyperpigmentation or hypopigmentation (38.4%), venous dilation near the fistula (22.2%), eczema in the fistula area (14.8%), half-and-half nails (13.5%), onychodystrophy (6.1%), subungual hemorrhage (4.5%), leukonychia (4.5%), stomatitis (5.6%), xerostomia (3.2%), gingivitis (2.4%), uremic breath (2.1%), and skin calcificatins (0.4%). Nephrogenic fibrosing dermopathy was not detected in any of our patients.

CONCLUSIONS

Pruritus, paleness, dry skin as well as hyperpigmentation and hypopigmentation are the most frequent skin abnormalities observed in hemodialysis patients. The early recognition of some cutaneous conditions associated with end stage renal failure and hemodialysis may allow early therapeutic intervention and decrease morbidity.

Imatinib mesylate-induced pseudoporphyria in two children

Imatinib mesylate was the first of several tyrosine kinase inhibitors approved for use in the treatment of a number of human cancers. Adverse cutaneous reactions to imatinib are common. Pseudoporphyria has been infrequently reported in adults undergoing imatinib therapy for chronic myeloid leukemia. We present two children with pseudoporphyria induced by imatinib therapy for hematologic malignancies. In view of the burgeoning use of imatinib in children, physicians should be aware that pseudoporphyria may develop as a consequence of imatinib therapy.

Pseudoporphyria following self-medication with chlorophyll

Two cases of pseudoporphyria are described in which the clinical features of porphyria cutanea tarda occurred in the absence of abnormalities in porphyrin metabolism. Both patients presented with skin fragility and bullae on the dorsal aspect of the hands. The patients consumed a commercial liquid chlorophyll drink in which we detected fluorescent compounds with characteristics typical of previously described chlorophyll derived photosensitisers.

Cutaneous porphyrias part I: epidemiology, pathogenesis, presentation, diagnosis, and histopathology

The porphyrias are a group of disorders characterized by defects in the heme biosynthesis pathway. Many present with skin findings including photosensitivity, bullae, hypertrichosis, and scarring. Systemic symptoms may include abdominal pain, neuropsychiatric changes, anemia, and liver disease. With advances in DNA analysis, researchers are discovering the underlying genetic causes of the porphyrias, enabling family members to be tested for genetic mutations. Here we present a comprehensive review of porphyria focusing on those with cutaneous manifestations. In Part I, we have included the epidemiology, pathogenesis, presentation, diagnosis, and histopathology. Treatment and management options will be discussed in Part II.

Pseudoporphyria Associated with Nonhemodialyzed Renal Insufficiency, Successfully Treated with Oral N-Acetylcysteine

Pseudoporphyria (PP) is a relatively rare, photodistributed bullous dermatosis that resembles porphyria cutanea tarda (PCT), but it is not accompanied by porphyrin abnormalities in the serum, urine, or stool. It was initially described in renal failure patients on dialysis. Thereafter, it has been associated with several aetiological factors. We report a case of PP in a 67-year-old woman with mild renal failure, successfully treated with N-acetylcysteine. This is the second reported case of PP developing in nondialyzed chronic renal failure. Such cases support the view that renal impairment itself may play a more important aetiological role in developing PP than it was originally considered.

Cutaneous manifestations in end-stage renal disease

The prevalence of chronic kidney disease has increased over the last years. The effects of this disease are complex and may lead to dysfunction of multiple organs, including the skin, with most patients presenting with at least one dermatologic alteration. Sometimes these symptoms can be the first clear sign of kidney disease. This article discusses the skin manifestations related to severe renal impairment or end-stage renal disease (ESRD), which are divided into nonspecific and specific, and reviews the clinical features, etiopathogenesis and therapeutic options for these dermatoses. Early recognition and treatment reduce morbidity and improve these patients' quality of life.

Pseudoporfiria induzida pela diálise tratada com N-acetilcisteína oral

Pseudoporfiria é dermatose bolhosa rara, semelhante clínica e histopatologicamente à porfiria cutânea tardia. Acomete, principalmente, pacientes renais crônicos em diálise peritoneal ou hemodiálise. Medicamentos também podem ser envolvidos na etiologia. O diagnóstico e o manejo desta entidade é um desafio para os dermatologistas. Os autores demonstram um caso de pseudoporfiria, relacionada à diálise, com evolução favorável após o uso de N-acetilcisteína oral.

Bullous skin lesions in a patient undergoing chronic hemodialysis

Porphyria cutanea tarda (PCT) is a vesiculobullous skin disorder characterized by a defect in heme biosynthesis. Reduced activity of the hepatic enzyme uroporphyrinogen decarboxylase (URO-D) results in accumulation of photosensitive porphyrins; this ultimately leads to the skin fragility and blistering that is characteristic of this disease. The majority of cases of PCT are associated with acquired deficiencies of the enzyme URO-D, secondary to hepatic injury precipitated by medications or infections. Less commonly, PCT has been documented in patients with end-stage renal disease. The pathogenesis of PCT in long-term hemodialysis (HD) has been attributed to many factors, but the following mechanisms have been implicated: (i) decreased hepatic URO-D activity due to suppressive effects of iron and other hepatotoxins and (ii) poor porphyrin clearance by renal replacement therapies. We report a case of PCT that developed in a patient on maintenance HD for 4 years. He had a history of hepatitis C and evidence of iron overload. However, as the patient was anemic, therapeutic phlebotomy was problematic and therefore erythrocyte-stimulating agents were maximized to mobilize iron stores and allow phlebotomy. With this treatment, the patient's skin lesions improved in conjunction with decreasing ferritin levels.