Recessive dystrophic epidermolysis bullosa complicated with nephrotic syndrome due to secondary amyloidosis

Elevated expression of interleukin-6 (IL-6) and serum amyloid A (SAA) in the skin and the serum of recessive dystrophic epidermolysis bullosa: Skin as a possible source of IL-6 through Toll-like receptor ligands and SAA

The effect of persistent skin inflammation on extracutaneous organs and blood is not well studied. Patients with recessive dystrophic epidermolysis bullosa (RDEB), a severe form of the inherited blistering skin disorder, have widespread and persistent skin ulcers, and they develop various complications including anaemia, hyperglobulinaemia, hypoalbuminaemia and secondary amyloidosis. These complications are associated with the bioactivities of IL-6, and the development of secondary amyloidosis requires the persistent elevation of serum amyloid A (SAA) level. We found that patients with RDEB had significantly higher serum levels of IL-6 and SAA compared to healthy volunteers and patients with psoriasis or atopic dermatitis. Both IL-6 and SAA were highly expressed in epidermal keratinocytes and dermal fibroblasts of the skin ulcer lesions. Keratinocytes and fibroblasts surrounding the ulcer lesions are continuously exposed to Toll-like receptor (TLR) ligands, pathogen-associated and damage-associated molecular pattern molecules. In vitro, TLR ligands induced IL-6 expression via NF-κB in normal human epidermal keratinocytes (NHEKs) and dermal fibroblasts (NHDFs). SAA further induced the expression of IL-6 via TLR1/2 and NF-κB in NHEKs and NHDFs. The limitation of this study is that NHEKs and NHDFs were not derived from RDEB patients. These observations suggest that TLR-mediated persistent skin inflammation might increase the risk of IL-6-related systemic complications, including RDEB.

Kidney and Urinary Tract Involvement in Epidermolysis Bullosa: Is Routine Follow-Up Necessary?

Background

Several renal and urinary tract complications have been reported in patients with epidermolysis bullosa.

Objective

This study investigated kidney and urinary tract involvement in patients with epidermolysis bullosa.

Patients and Methods

Patients with epidermolysis bullosa in treatment at the Dermatology Unit were included in the study. Glomerular and tubular functions were investigated.

Results

The study included 16 patients (4 females, 12 males) of mean 11.1 years (SD = 8.1 years). Estimated GFR was normal in all patients except one with end-stage renal disease. Excluding this patient, the urinary albumin/creatinine ratio and the fractional excretion of sodium were normal. The mean beta-2 microglobulin/creatinine ratio was 278.8 μg/g, and it was abnormally high in 2 patients. The mean tubular phosphorus reabsorption was 92.6%; it was abnormally low in 1 patient. Severe kidney or urinary tract involvement was present in 2 patients with recessive dystrophic EB-generalized severe (RDEB-GS): one patient had obstructive bullous lesions in the urethra; the other had end-stage renal disease secondary to focal segmental glomerulosclerosis and was on peritoneal dialysis for 3 years.

Conclusions

Assessment for renal and urinary tract involvement should become a routine part of the evaluation of patients with any type of EB, but especially of patients with RDEB-GS. Patients with mild tubular dysfunction need long-term follow-up to detect early deterioration of renal function.

Emaciation, Congestive Heart Failure, and Systemic Amyloidosis in Severe Recessive Dystrophic Epidermolysis Bullosa: Possible Internal Complications Due to Skin-Derived Inflammatory Cytokines Derived from the Injured Skin

Inherited epidermolysis bullosa (EB) is a rare genetic skin disorder characterized by epithelial tissue fragility. Recessive dystrophic epidermolysis bullosa (RDEB) is the most severe form, characterized by the presence of blisters, erosion, and ulcer formation, leading to scarring and contraction of the limbs. RDEB is also associated with extra-cutaneous complications, including emaciation, congestive heart failure, and systemic amyloidosis. The main cause of these clinical complications is unknown; however, we hypothesized that they are caused by elevated circulating inflammatory cytokines overproduced by injured keratinocytes. We addressed this phenomenon using keratin-14 driven, caspase-1 overexpressing, transgenic (KCASP1Tg) mice in which injured keratinocytes release high levels of IL-1α and β. KCASP1Tg showed severe spontaneous dermatitis, as well as systemic complications, including aberrant weight loss, cardiovascular disease, and extensive amyloid deposition with organ dysfunction, resembling the complications observed in severe EB. These morbid conditions were partially ameliorated by simultaneous administration of anti-IL-1α and β antibodies. The skin not only constitutes a physical barrier, but also functions as the largest immune organ. We suggest a novel role for IL-1 in the pathogenesis of EB and the use of anti-IL-1 antibodies as a potential therapy for EB complications.

Epidermolysis bullosa. Part 1: causes, presentation and complications

This article is the first in a series of three focusing on the causes, clinical presentation, complications and care of adult patients affected by epidermolysis bullosa (EB), a group of rare genetic skin fragility disorders. Although the condition is rare, in some cases it presents extreme challenges both to those affected and those involved in the care of the EB patient; therefore, these articles may have relevance for other long-term disorders. While there is a wealth of information regarding the 'science' of EB there is dearth of information regarding the care of the adult EB patient, and this series of articles will endeavour to fill that gap. This article focuses mainly on those patients affected with the most severe form of EB found in the adult group, recessive dystrophic epidermolysis bullosa; with the part two looking at the care of the adult with EB from the nursing perspective, including wound management, and the experiences of a specialist EB psychotherapist being presented in the final article of the series. Readers will thus have an opportunity to gain an overall view of this difficult condition.

Nephro-urological complications of epidermolysis bullosa in paediatric patients

A small but important proportion of patients with epidermolysis bullosa (EB) may develop significant renal and urological complications which can have a major impact on their morbidity and mortality. During the last 10 years, five of a large group of children with EB under our care, with either dystrophic or junctional types of disease, experienced major nephro-urological complications. Two patients with recessive dystrophic EB (REDB) developed macroscopic haematuria - one had renal failure and underwent a renal biopsy showing IgA nephropathy. A third patient with RDEB also developed renal failure and his biopsy demonstrated postinfectious glomerulonephritis/type III membranoproliferative (mesangiocapillary) glomerulonephritis. Both patients with renal failure underwent peritoneal dialysis. Two patients with junctional EB developed obstructive uropathies, which required bladder reconstruction and the fashioning of a Mitrofanoff channel in one.

[Systemic amyloidoses]

Amyloidoses are a heterogeneous group of diseases characterized by extracellular fibrillar protein deposits in the organs and tissues. These proteins are not biochemically related to each other, but share certain common characteristics, including apple green birefringence with polarized light after staining with Congo red, and beta-pleated sheet configuration through x-ray diffraction. Amyloid deposits may occur in many organs (systemic amyloidoses) or may affect a single tissue (localized or organ-specific amyloidoses). There are different classifications, but in this review the amyloidoses are organized by clinical symptoms, which are determined by the amyloid protein involved. Special attention is given to cutaneous and mucous membrane manifestations, which are often the first sign of the disease and are useful for early diagnosis, thus avoiding more aggressive procedures. The involvement of other organs is analyzed, as are the diagnosis, prognosis and treatment of systemic amyloidoses.

Épidermolyse bulleuse dystrophique récessive d’Hallopeau-Siemens associée à une glomérulonéphrite à dépôts mésangiaux d’IgA : 4 cas

BACKGROUND

The Hallopeau-Siemens type of recessive dystrophic epidermolysis bullosa (HS-RDEB) is a severe hereditary dermatosis, associated with a collagen VII deficiency. A chronic inflammatory syndrome, secondary to recurrent cutaneous infections, may be the cause of AA amyloidosis, with chronic renal failure, involving life prognosis. Less frequently, an IgA glomerulonephritis may occur and induce renal failure. Only two cases have been previously described. We report herein four new cases.

CASE REPORT

We report four cases of HS-RDEB associated with IgA glomerulonephritis. A renal biopsy confirmed the diagnosis in all four cases. Later on, two patients had a second renal biopsy, indicated for deterioration of renal function. One of these patients showed AA type renal amyloidosis on the second biopsy. None of these six biopsies, conducted in our four patients led to local cutaneous complications. Subsequently three patients presented with terminal renal failure. Hemodialysis was set up, with good tolerance and improvement in quality of life.

DISCUSSION

IgA glomerulonephritis should be suspected if a patient with HS-RDEB presents with hematuria. Renal biopsy is not contraindicated, confirms the diagnosis and helps to specify the prognosis. Hemodialysis is possible and well tolerated in the terminal stage of renal failure. There is not enough evidence for a genetic link between HS-RDEB and IgA glomerulonephritis, but repeated skin infections may be involved in the pathophysiology of the renal disease.

Dystrophic epidermolysis bullosa complicated by cutaneous squamous cell carcinoma and pulmonary and renal amyloidosis

A 25-year-old woman with Hallopeau-Siemens recessive dystrophic epidermolysis bullosa had generalized blistering, scarring and milia since birth. In the course of the disease, acral pseudosyndactyly developed, and the patient suffered from corneal erosions, oesophageal strictures, malabsorption, recurrent severe pneumonias and nephrotic syndrome. In addition, she had severe anaemia, sideropaenia, hypocalcaemia, heavy proteinuria and hypoalbuminaemia. A rapidly growing skin squamous cell carcinoma developed on the neck that spread to axillary and cervical lymph nodes. Recurrent hypocalcaemic tetanic convulsions and dyspnoea and a pneumonia refractory to antibiotics led to the premature demise of the patient. Autopsy revealed extensive amyloidosis of the renal, hepatic and splenic tissues. AA type amyloid deposits were detected in the renal glomeruli and in the lung, explaining the patient's unusually severe pulmonary infections. In essence, the patient had severe recessive dystrophic epidermolysis bullosa, complicated by squamous cell carcinoma, recurrent pneumonias and nephrotic syndrome due to secondary amyloidosis of the kidney and lung. The possibility of secondary pulmonary amyloidosis should be considered in severe dystrophic epidermolysis bullosa patients with recurrent pulmonary infections.