Subfoveal choroidal neovascularization in a patient with Fabry's disease

INTRODUCTION

Fabry disease (FD) is an X-linked, inherited disorder caused by a deficiency of the enzyme alpha-galactosidase A, with progressive accumulation of glycosphingolipids within several tissues and organs, including the eye. Ophthalmological manifestations include conjunctival vessel tortuosity, cornea verticillata, lens opacity, and retinochoroidal vessel abnormalities.

REPORT

In FD, the presence of macular choroidal neovascularization (CNV) has never been previously described.

DISCUSSION

We report the case of a FD patient who developed an early-onset CNV, when he was still in his 40s.

Chronic renal failure, dialysis, and renal transplantation in Anderson-Fabry disease

Anderson-Fabry disease (AFd) is a rare, inherited, x-linked disease characterized by the deficiency of the lysosomal enzymatic alpha-galactosidase A activity (alpha-Gal-A). The enzyme defect leads to progressive accumulation of glycosphingolipids (GL) in all kinds of cells, tissues, organs, and body fluids. The clinical manifestations are very protean, the residual activity of alpha-Gal-A and/or different gene mutations might explain different phenotypes, but as yet these concepts have not been proven. Usually, patients with AFd show 3 clinical phases, more evident in men than in heterozygous women. The first phase (childhood and adolescence) is characterized by myalgia, arthralgia, acroparesthesia, fever, cutaneous angiokeratomas, and corneal opacities. The second phase is characterized mainly by renal involvement. In the third phase, severe renal impairment and involvement of cerebrovascular and cardiovascular systems are present. The progression to end-stage renal disease (ESRD) is common in hemizygous males (3rd-5th decade of life); usually, death occurs because of cerebral and/or cardiovascular complications in patients undergoing chronic dialysis therapies. The survival of patients with AFd in dialysis is better than in diabetic patients, but it clearly is decreased compared with uremic patients with other nephropathies, despite a lower mean age of uremia (50 versus 60 y). The outcome of kidney transplantation is similar to that found in other patients with ESRD, despite controversial issues published in the past. The use of a kidney donor with normal alpha-Gal-A activity in the control of the metabolic systemic disease is unproven. The recurrence of GL deposits in the kidney graft has been documented rarely. The definitive treatment for AFd is enzyme replacement therapy with purified alpha-Gal-A produced by a genetically engineered human cell line or Chinese hamster oocytes: relatively short-term studies have shown a significant treatment effect on clinical outcome measures.

Enzyme replacement therapy in Fabry's disease: recent advances and clinical applications

Fabry's disease is a rare X-linked recessive disorder resulting from deficient lysosomal enzyme, alpha-galactosidase A (alpha-Gal A) activity. The deficiency leads to progressive glycosphingolipid globotriaosylceramide (Gb3) accumulation in fluids and tissues, including vascular endothelium, connective tissue, kidney, heart, brain and peripheral nerves. Classic Fabry's disease in hemizygous males has high morbidity and mortality due to end-stage renal disease (ESRD) requiring hemodialysis (HD) or kidney transplantation, myocardial involvement and central nervous system (CNS) complications. Most heterozygous females can also suffer from this severe disease deterioration. Until recently, Fabry's disease management consisted of symptomatic and palliative treatment, but this has changed with the availability of the recombinant human alpha-Gal A enzyme, agalsidase. Two different agalsidase formulations have been obtained: one from human fibroblast (agalsidase alpha), and one from Chinese hamster ovary (CHO) cells (agalsidase beta). Both preparations underwent clinical trials that documented the feasibility, efficacy and safety of the treatment. In addition, several clinical observations have proved that agalsidase reduces the storage of the substrate from several organs and tissues and, consequently, improves signs and symptoms of Fabry's disease. Additional clinical experiences have confirmed the initial clinical trial results, but further studies are needed to evaluate the long-term outcome of enzyme replacement therapy (ERT). We reviewed the clinical trial observations, as well as subsequent clinical experiences with ERT in patients with Fabry's disease.

Enzyme replacement therapy with agalsidase beta in kidney transplant patients with Fabry disease: a pilot study

BACKGROUND

We sought to assess the safety and efficacy of enzyme replacement therapy (ERT) with recombinant human-alpha-galactosidase A (rh-alpha-Gal A) in kidney transplant recipients with Fabry disease, a previously unstudied population.

METHODS

Three male kidney transplant recipients with biochemically, genetically, and histologically confirmed Fabry disease and documented Fabry myocardiopathy received the rh-alpha-Gal A, agalsidase beta, 1 mg/kg of body weight every 2 weeks by intravenous infusion and were monitored biochemically, clinically, and electrocardiographically and echocardiographically for 18 months.

RESULTS

Patients showed biochemical, clinical/functional, and morphologic response to ERT. Plasma globotriaosylceramide decreased 23% to 50%. Extremity pain resolved within 2 months in the patient with this manifestation. On echocardiography, left ventricular mass, end diastolic diameter (EDD), and cardiac contractility, shown by ejection fraction (EF), improved in 2 of the 3 patients receiving essentially all planned infusions. EDD and EF remained basically stable, but cardiac morphologic abnormalities progressed in the other patient, who had a 5-month interruption in ERT after the initial month. Mild mitral insufficiency persisted in all patients, as did atrial fibrillation in the affected individual. After a combined total of 116 infusions, no treatment-related adverse event, intolerance, or seroconversion was seen. Renal function remained stable and the immunosuppression regimen unchanged in all patients.

CONCLUSION

Our pilot study provides preliminary evidence that ERT with agalsidase beta, 1 mg/kg every 2 weeks, is safe and often effective against extra-renal manifestations in kidney transplant patients with Fabry disease. Studies with longer courses of this and higher doses of ERT are merited in this population.

Geminga's tails: a pulsar bow shock probing the interstellar medium

We report the X-ray Multimirror Mission-Newton European Photon Imaging Camera observation of two elongated parallel x-ray tails trailing the pulsar Geminga. They are aligned with the object's supersonic motion, extend for approximately 2', and have a nonthermal spectrum produced by electron-synchrotron emission in the bow shock between the pulsar wind and the surrounding medium. Electron lifetime against synchrotron cooling matches the source transit time over the x-ray features' length. Such an x-ray detection of a pulsar bow shock (with no Halpha emission) allows us to gauge the pulsar electron injection energy and the shock magnetic field while constraining the angle of Geminga's motion and the local matter density.

Ethylene-oxide and steam-sterilised polysulfone membrane in dialysis patients with eosinophilia

Eosinophilia and some acute dialysis side-effects, such as itching, flushing and bronchospasm, are often associated with the presence of ethylene oxide (ETO) as dialyzer sterilizing agent. This study evaluated the effects of two different polysulfone (PS) hollow-fiber dialysers sterilized with ETO and steam in 31 chronic dialysis patients with eosinophilia. Clinical symptoms, metabolic and biochemical parameters, complement (C3a and C5a) activation and production were evaluated in each patient dialysed for two months at a time with Cuprophan dialyser, ETO-PS dialyser and steam-PS dialyser. The steam-sterilizer agent does not alter the purifying capacity of the PS membrane which maintains its superiority over Cuprophan in terms of biocompatibility. Using steam-PS, intradialytic eosinophil kinetics seems to improve. In some patients with high serum levels of ETO-specific IgE these levels tend to diminish. Generic intradialytic symptoms do not differ between the two sterilization methods, although some hypersensitivity symptoms during the first dialysis hour are considerably lower in some patients when steam-sterilized PS is used.

[Destructive cervical amyloidotic spondyloarthropathy in patients undergoing periodic dialysis. Personal experience]

The accumulation of amyloid (beta 2-microglobulin) in several organs and tissues of patients in chronic dialysis is a recent pathologic condition. A wide range of cases, supported by specific tests for amyloid on bioptic and autoptic samples, showed a radiographic semiology of osteostructural alterations in various areas which allows amyloidotic condition of bone to be diagnosed with high reliability. In 11 of 62 patients (17.74%) we observed destructive cervical amyloidotic spondyloarthropathy (DCAS). The radiological patterns common to all patients were subchondral sclerosis, erosions of vertebral body plates, widening/narrowing of intervertebral spaces, no/poor osteophytosis. Over-hanging was present in 54.5% of cases, and deformation of vertebral bodies in 45.4%. CT was useful in improving the definition of the various alterations, and in locating others, such as cavitations in vertebral bodies and involvement of apophyseal joints. Constant factors were the association with extravertebral osseous amyloidosis, dyalitic age over 60 months, and the use of Cuprophan membranes for dialysis. The frequent (72.72%) association with alterations involving the lumbar rachis (subchondral sclerosis, erosions and geodes) was suggestive of amyloidotic condition.

Normalization of renal function and blood pressure after dissolution with intra-arterial fibrinolytics of a massive renal artery embolism to a solitary functioning kidney

The intra-arterial administration of fibrinolytics in a massive embolism to the renal artery of a solitary functioning kidney determined quick normalization of the severe renal failure and hypertension.

Percutaneous transluminal dilatation of posttransplant renal artery stenosis: beneficial effects in two cases at high surgical risk

Two clinical cases are described in which percutaneous transluminal dilatation (PTD) determined the correction of hypertension and renal hypoperfusion due to renal artery stenosis of the transplanted kidney.