Dear Cardiologist:

Patients with classical Fabry Disease are seen in a cardiologist’s office in adulthood with various cardiac symptoms, including arrythmias, valvular involvement and left ventricular hypertrophy. Your patients’ other complaints may be episodic paresthesia, hypohidrosis, heat and cold intolerance, angiokeratoma, gastrointestinal distress and diarrhea. In the last decade, an atypical variant of Fabry Disease has been reported in which manifestations of the disease are limited to the heart (cardiac variant). An assessment of the incidence of hemizygosity for Fabry Disease in patients with left ventricular hypertrophy in 1995 resulted in an estimate of 3%, indicating that Fabry Disease should be considered as a cause in unexplained left ventricular hypertrophy (S. Nakao et al., New Engl. J. Med. 1995;333: 288-293).

The symptoms may be caused by deposits of a glycolipid, globotriaosylceramide, that cannot be degraded due to an enzymatic defect in the lysosomal enzyme alpha–galactosidase A, the cause of Fabry disease. This disease follows an X-linked inheritance, so your male patients are homozygotes, while cardiac symptoms in female heterozygotes are mild or non existent. The progressive accumulation of glycolipids, mainly in the walls of blood vessels, causes multiple organ impairment and dysfunction and most patients succumb in their forties or fifties to renal failure, cardiovascular and/or cerebrovascular disease. A goal of research into Fabry disease has been to provide the missing alpha-galactosidase enzyme for degradation of these glycolipids to patients diagnosed early in life.

Enzyme replacement therapy is now available to prevent the progression to heart and kidney damage, stroke and untimely death, and provide relief for early symptoms. The FDA has approved the therapy for treatment of patients. Your patients are eligible for TESTING. If their diagnosis is confirmed by a simple test of alpha-galactosidase activity in their blood sample, they can be evaluated for treatment.

We would like to solicit your help in identifying patients with Fabry disease. Please check your charts for patients displaying the above-mentioned symptoms, and then send them a letter informing them of the availability of testing. Enclosed please find a draft of that type of letter providing the relevant information on how to obtain a testing kit that maybe used in any physician’s office. You may copy this letter onto your letterhead and modify it in any way you feel is appropriate. It will be the patient’s decision to follow up on this letter, but we would appreciate your encouragement. Enzyme replacement therapy for a similar disease, Gaucher’s disease, is one of the most successful applications of modern science and has helped many patients to lead normal lives without the pain and complications of that disease. We hope to provide similar relief to patients with Fabry disease by replacing the missing alpha-galactosidase enzyme. Their lives may depend on it.

We thank you for your efforts and cooperation, and we are certain your patients will, too.

Dear Cardiologist Patient Draft