Fucosidosis is a disorder that may have a variable presentation even in individuals belonging to one family. Even though the symptoms elicited remain the same, patients may be affected by fucosidosis with an early onset and rapid progression, or a disease that is diagnosed during adolescence and progresses slowly with less profound symptoms.

The most severe type of fucosidosis tends to initially manifest at a time between the 6th month to the 1st year of an infant's life. Symptoms include psychomotor retardation, namely the slowing-down of emotional and physical reactions to various stimuli. Other findings that may be revealed in a physical examination may include [1]:

• Coarse facial features, such as large lips and nose, prominent forehead, widely spaced teeth
• Mild dysostosis multiplex
• Hypotonia
• Significant growth retardation

Fucosidosis primarily leads to a neurodegeneration due to central nervous system myelin loss. This is evident by means of mental retardation, loss of coordination, and rigidity of the extremities that involves extension and rotation (decerebrate rigidity) [2] [3] [4]. As the disease progresses, the loss of weight and muscle mass sustained may constitute life-threatening sequelae that can lead to a patient's demise even within the first years of life.

Other signs related to fucosidosis include visceromegaly that can affect the spleen, liver, and heart, epilepsy, hearing impairment or total hearing loss, kyphoscoliosis, and persistent respiratory infections. Hyperhidrosis is another potential symptom.

Symptoms are identical in less severe as well as more severe forms of Fucosidosis. However, they may be milder and may progress more slowly in the less severe forms. Angiokeratomas usually form on the skin at the age of approximately 2 years and are primarily found on the abdomen, thighs, and genital areas. Contractures, spasticity, and anhidrosis may also complicate the clinical picture.

The first step towards a successful diagnosis of Fucosidosis is a detailed medical history and a meticulous clinical examination. The patients are, in the majority of the cases, in their first year of life and parents report signs associated with mental retardation; the infant also appears to be lacking in terms of growth and neurological development. Characteristic skeletal and facial features are also noticeable and may indicate the diagnosis. Further tests that may be employed in order to diagnose Fucosidosis include:

• Electron microscopy samples are harvested from the heart, liver, spleen, lung and other viscera. Electron microscopy reveals intracellular vacuoles, either clear or filled with granulomatous/lamellar bodies.
• Magnetic resonance imaging (MRI), computerized tomography (CT) are both employed in order to detect degenerative alterations of the cerebral parenchyma. The use of CT scans has specifically increased during the recent years [5] [6] [7].
• Urinalysis may illustrate fucose-containing complex compounds.
• Enzyme assays show decreased activity of the enzyme alpha-L-fucosidase.
• Prenatal testing: Fucosidosis can also be confirmed prenatally, by means of chorionic villus sampling (CVS) and amniocentesis.

1. Willems PJ, Gatti R, Darby JK, et al. Fucosidosis Revisited: A Review of 77 Patients. Am J Med Genet. 1991;38(1):111–131
2. Folkerth RD. Abnormalities of developing white matter in lysosomal storage diseases. J Neuropathol Exp Neurol. 1999;58:887–902.
3. Prietsch V, Arnold S, Kraegeloh-Mann I, et al. Severe hypomyelination as the leading neuroradiological sign in a patient with fucosidosis. Neuropediatr. 2008;39:51–4
4. Steenweg ME, Vanderver A, Blaser S, et al. Magnetic resonance imaging pattern recognition in hypomyelinating disorders. Brain. 2010 Oct;133(10):2971-82
5. Terespolsky D, Clark JT, Blaser SI. Evolution of the Neuroimaging Changes in Fucosidosis Type II. J Inherit Metab Dis. 1996;19(6):775–781
6. Smith-Bindman R, Lipson J, Marcus R, et al. Radiation dose associated with common computed tomography examinations and the associated lifetime attributable risk of cancer. Arch Intern Med. 2009 Dec 14;169(22):2078-86.
7. Berrington de González A, Mahesh M, Kim KP, et al. Projected cancer risks from computed tomographic scans performed in the United States in 2007. Arch Intern Med. 2009 Dec 14;169(22):2071-7.