21 - 127 - FABRY DISEASE

Question 1

Fabry disease is a rare X-linked metabolic disorder caused by the partial or complete deficiency of a lysosomal enzyme ________

Answer 1

α-galactosidase A

Question 2

What glycosphingolipids predominantly accumulates in Fabry disease?

Answer 2

globotriaosylceramide

As a result of this enzyme deficiency, neutral sphingolipids with terminal α-galactosyl residues (predominantly globotriaosylceramide [Gb3]) accumulate in the lysosomes of different tissues and fluids (epithelial cells of glomeruli and tubules of the kidneys; cardiac myocytes; ganglion cells of the autonomic system; cornea; endothelial, perithelial, and smooth muscle cells of blood vessels; and histiocytic and reticular cells of connective tissue).

Question 3

Question 4

cutaneous hallmark of Fabry disease

Answer 4

Angiokeratomas

(pinpoint to 4 mm diameter, dark-red to blue-black, macular and papular lesions that do not blanch on pressure)

Question 5

Answer 5

Angiokeratomas are also seen on the proximal limbs, particularly their medial aspects, the elbows and knees, the palms and soles, and over the distal phalanges of the digits (Fig. 127-4).

Question 6

Answer 6

Lesions may occur on the lips, particularly along the vermilion border, and occasionally on the mucosal surfaces (Fig. 127-5).

Question 7

Answer 7

In females, angiokeratomas are usually sparsely distributed (Fig. 127-6), and may occasionally occur in a dermatomal distribution.13 The most common sites are the trunk and proximal limbs. 13 Female genital lesions are relatively infrequent.

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Question 16

Which of the following is true regarding Fabry Disease, except?

a. The cutaneous hallmark of this X – linked metabolic disorder are angiokeratomas. This is present in 70% of males and 39% of females
b. Up to a third of Fabry males and two-thirds of Fabry females hav angiokeratomas
c. Cutaneous vascular lesions is associated with higher disease severity scores
d. Angiokeratomas are seen typically in bathing trunk area of males, while in females these are sparsely distributed and may occasionally occur in a dermatomal distribution.

Answer 16

Answer: B p. 2295 …DO NOT have angiokeratomas

Question 17

Which enzyme accumulates in the lysosomes of different tissues and fluids in patients with Fabry Disease

a. Alpha- galactosidase A
b. Chondroitin sulfate
c. Globotriaosylceramide
d. Cerebroside

Answer 17

Answer: C – elevated levels of globotriaosylsphingosine accumulate in the lysosomes of diff tissues and fluids a- Deficient lysosomal enzyme

Question 18

Which of the following is true regarding Fabry Disease

a. Females die in the 4th -5 th decade, while males live perhaps 15 years longer
b. Right ventricular hypertrophy is a common cardiac manifestation of Fabry disease
c. Renal manifestation is a constant feature and increasingly recognized as the major cause of death in both male and female patients
d. Renal manifestations are seen in more

than 90% of males

Answer 18

Answer: D

A. males with fabry disease die in 4-5th decade, females live perhaps 15 years longer p. 2300

B. leFFFt ventricular hypertrophy p. 2299 FFFABRY

C. Cardiac manifestation p. 2299

D. True p. 2299

Question 19

True/False: Hypohidrosis is a classical feature of Fabry diseases. It is more common in male patients than females, while hyperhidrosis occur more often in females

a. True
b. False

Answer 19

Answer: A. Hypohidrosis was reported by 53% of males and 28% females. Hyperhidrosis occur more often in females than males p. 2297

Question 20

Agalsidase beta (Genzyme) is administered
a. 1mg/kg twice a week

b. 0.2 mg/kg twice a week
c. 1mg/kg twice a day
d. 0.2 mg/kg twice a day

Answer 20

Answer:

A. 1mg/kg biweekly – agalsidase beta p. 2303

B. 0.2mg/kg biweekly – agalsidase alpha