Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 2-1984. A 47-year-old man with coronary-artery disease and variable neurologic abnormalities

Atherosclerosis in Fabry Disease-A Contemporary Review

Fabry disease (FD) is a lysosomal storage disorder characterised by a deficiency in the enzyme α-galactosidase A resulting in sphingolipid deposition which causes progressive cardiac, renal, and cerebral manifestations. The case illustrates a patient with FD who died suddenly, and medical examination demonstrated myocardial scarring and prior infarction. Angina is a frequent symptom in FD. Our own data are consistent with registry data indicating a high prevalence of risk factors for coronary artery disease (CAD) in FD that may accelerate conventional atherosclerosis. Patients with FD also have a higher high-density lipoprotein (HDL)/total cholesterol (T-Chol) ratio which may further accelerate atherosclerosis through expression of early atherosclerotic markers. Patients with FD may develop CAD both via classical atherosclerosis and through formation of thickened fibrocellular intima containing fibroblasts with storage of sphingolipids. Both mechanisms occurring together may accelerate coronary stenosis, as well as alter myocardial blood flow. Our data supports limited data that, although coronary flow may be reduced, the prevalence of epicardial coronary stenosis is low in FD. Microvascular dysfunction and arterial wall stress from sphingolipid deposition may form reactive oxygen species (ROS) and myeloperoxidase (MPO), key atherosclerotic mediators. Reduced myocardial blood flow in FD has also been demonstrated using numerous imaging modalities suggesting perfusion mismatch. This review describes the above mechanisms in detail, highlighting the importance of modifying cardiovascular risk factors in FD patients who likely develop accelerated atherosclerosis compared to the general population.

Fabry disease - underestimated in the differential diagnosis of multiple sclerosis?

Objective

Fabry disease is a rare X-linked inherited lysosomal storage disorder affecting multiple organ systems. It includes central nervous system involvement via micro- and macroangiopathic cerebral changes. Due to its clinical symptoms and frequent MRI lesions, Fabry disease is commonly misdiagnosed as multiple sclerosis. We present an overview of cases from Fabry centres in Germany initially misdiagnosed with multiple sclerosis and report the clinical, MR-tomographical, and laboratory findings.

Methods

Eleven Fabry patients (one male, ten females) initially diagnosed with multiple sclerosis were identified from 187 patient records (5.9%) and analyzed for presenting symptoms, results of the initial diagnostic workup, and the clinical course of the disease.

Results

Four patients were identified as having a “possible” history of MS, and 7 patients as “definite” cases of multiple sclerosis (revised McDonald criteria). On average, Fabry disease was diagnosed 8.2 years (±9.8 years) after the MS diagnosis, and 12.8 years after onset of first symptoms (±10.3 years). All patients revealed white matter lesions on MRI. The lesion pattern and results of cerebrospinal fluid examination were inconsistent and non-specific. White matter lesion volumes ranged from 8.9 mL to 34.8 mL (mean 17.8 mL±11.4 mL). There was no association between extra-neurological manifestations or enzyme activity and lesion load.

Conclusion

There are several anamnestic and clinical hints indicating when Fabry disease should be considered a relevant differential diagnosis of multiple sclerosis, e.g. female patients with asymmetric, confluent white matter lesions on MRI, normal spinal MR imaging, ectatic vertebrobasilar arteries, proteinuria, or lack of intrathecally derived immunoglobulin synthesis.

White matter lesions in Fabry disease occur in 'prior' selectively hypometabolic and hyperperfused brain regions

Fabry disease is an X-linked disorder associated with early onset stroke. We previously found a significantly elevated cerebral blood flow (CBF) in patients with Fabry disease. We set to determine whether elevated resting CBF in Fabry disease is primarily a cerebrovascular abnormality or is secondary to enhanced neuronal metabolism. The relationship of cerebral metabolism and blood flow to Fabry leukoencephalopathy was also investigated. We measured the global and regional cerebral metabolic rate of glucose using 18-fluoro-deoxyglucose (FDG) and PET in 16 patients with Fabry disease (7 patients with leukoaraiotic lesions and 9 without) and in 7 control subjects. MRI fluid attenuated inversion recovery (FLAIR) studies were also performed in the patient and control groups. All control subjects had normal MRI FLAIR studies with no high-signal deep white matter lesions (WML). Patients were partitioned into FLAIR lesion and non-FLAIR lesion groups. We found no evidence of cerebral glucose hypermetabolism in Fabry disease. On the contrary, significantly decreased regional cerebral glucose metabolism (rCMRGlu) was found particularly in the deep white matter in the Fabry non-lesion group and exacerbated in the lesion group. Lesion-susceptible regions were relatively hyperperfused in non-lesion patients compared to the control group. We conclude that the elevated rCBF and decreased white matter rCMRGlu indicates a dissociation between metabolism and blood flow suggesting chronic deep white matter metabolic insufficiency.

Excellent outcome of renal transplantation in patients with Fabry's disease

INTRODUCTION

Fabry's disease is an X-linked error of glycosphingolipid metabolism. Clinical manifestations of the disease are secondary to accumulation of glycosphingolipids in various tissues. Renal failure and vascular complications are common. There are conflicting reports regarding the outcomes of patients with Fabry's disease after renal transplantation.

METHODS

We reviewed the United States Renal Data System Registry database from 1988 and 1998, and found 93 patients with Fabry's disease who had received a renal transplant. Case-matched patients were identified to serve as controls.

RESULTS

Patients with Fabry's disease demonstrated equivalent 5-year patient and graft survival, compared with controls (83% and 75%, respectively, for those with Fabry's disease vs. 82% and 67% for controls).

CONCLUSION

Despite their high risk for cardiovascular complications, patients with Fabry's disease have excellent outcomes after renal transplantation.

Cerebrovascular complications of Fabry's disease

Fabry's disease (FD) is a rare, sex-linked disorder resulting from alpha-galactosidase deficiency. Cerebrovascular complications have been reported in the literature but have not been systematically analyzed. We report 2 patients and review 51 previously reported cases (descriptive meta-analysis) to clarify the clinical, radiologic, and pathologic features. The average age at onset of cerebrovascular symptoms was 33.8 years for hemizygous individuals (n = 43) and 40.3 years of heterozygotes (n = 10). The most frequent symptoms and signs were as follows (in descending order of frequency): hemiparesis, vertigo/dizziness, diplopia, dysarthria, nystagmus, nausea/vomiting, head pain, hemiataxia, and ataxia of gait, in the hemizygote group; and memory loss, dizziness, ataxia, hemiparesis, loss of consciousness and hemisensory symptoms, in the heterozygote group. The vertebrobasilar circulation was symptomatic in 67% of the hemizygotes and 60% of the heterozygotes. Intracerebral hemorrhage was found in 4 patients (3 hemizygotes and 1 heterozygote). Elongated, ectatic, tortuous vertebral and basilar arteries were the most common angiographic and pathologic features. For the hemizygotes, the recurrence rate for cerebrovascular disease was 76% and the death rate was 55%; 86% of the heterozygotes had recurrent cerebrovascular event(s) and 40% died. The cerebrovascular manifestations of FD, in both hemizygotes and heterozygotes, are predominantly due to dilative arteriopathy of the vertebrobasilar circulation, frequently recur, and portend a poor prognosis.

Nervous system involvement in Fabry's disease: clinicopathological and biochemical correlation

A detailed neuropathological and biochemical study was performed to evaluate the accumulation of ceramide trihexoside within the central and peripheral nervous systems of 2 patients with Fabry's disease. Luxol fast blue-staining lipid was noted in the leptomeninges and in the choroidal stroma; biochemical studies showed increased quantities of ceramide trihexoside in the cerebrospinal fluid. The permeable blood-brain barrier regions of the central and peripheral nervous systems contained increased quantities of ceramide trihexoside. Some central nervous system nuclei associated with autonomic function were also noted to store lipid. Other areas of increased ceramide trihexoside accumulation included specific cortical and brainstem structures. Possible sources for this selective accumulation of ceramide trihexoside within the central and peripheral nervous system include transport of glycolipid from the systemic vascular network and retrograde transsynaptic glycolipid transport.

Endomyocardial biopsy: a review of the literature

A review of the literature relating to endomyocardial biopsy (EMB) is presented. This is considered important at this time since EMB is being utilized with increasing frequency, particularly for the diagnosis of myocarditis. The development of the technique is briefly outlined. Emphasis is placed on the clinical application of EMB in the various primary cardiomyopathies (dilated, hypertrophic, restrictive, and obliterative), the infiltrative secondary cardiomyopathies (amyloidosis, sarcoidosis, hemochromatosis), myocarditis, as well as such conditions as adriamycin cardiotoxicity, cardiac transplant rejection, and Kawasaki disease. More controversial application of EMB in primary mitral valve prolapse (Barlow's syndrome), idiopathic ventricular arrhythmias, and the elucidation of the enigmatic finding of angina with angiographically normal coronary arteries is detailed. Experience with immunological and biochemical investigation of biopsy material, as well as with virus isolation and drug assays in the myocardium, is alluded to. Complications encountered with this procedure are also discussed, and its future role is contemplated.