MENKES DISEASE – CLASSIC OR INFANTILE ONSET FORM

ALTERNATE NAMES

Classical Menkes Disease; Congenital Hypocupremia; Menkes Syndrome; Steely Hair Disease; X-Linked Copper Deficiency

DESCRIPTION

Menkes disease (MNK) is a rare inherited neurodegenerative disorder that is caused by mutations in the ATP7A gene, resulting in abnormal uptake and metabolism of copper in cells of the body. Low copper levels can affect the structure of bone, skin, hair, and blood vessels and interfere with nerve function. Copper also builds up in the small intestine and kidneys. MNK is characterized by loss of developmental milestones, hypotonia (floppy muscle tone), seizures, feeding difficulties, failure to thrive, subnormal body temperature, and strikingly peculiar hair, which is often colorless or steel colored, and breaks easily. MNK - Classic form is the most severe type of this disorder and has an infantile onset (usually beginning at age two to three months).

DIAGNOSTIC TESTING, PHYSICAL FINDINGS, AND ICD-9-CM/ICD-10-CM CODING

Diagnostic testing:

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  Low copper and ceruloplasmin levels in the blood;

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  Skin biopsy and fibroblast culture documenting abnormal copper metabolism; and

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  Microscopic examination of the hair showing characteristic menkes abnormalities; molecular genetic testing showing ATP7A mutations.

Physical findings:

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  Characteristic brittle, colorless hair that breaks easily;

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  Poor growth/failure to thrive;

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  Hypotonia (floppy muscle tone);

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  Skeletal deformities and weak bones (osteoporosis); and

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  Global developmental delays.

ICD-9: 759.89

ICD-10: E83.09

PROGRESSION

Children with classic or infantile onset MNK appear normal at birth, and then start showing symptoms around two or three months of age. The prognosis for infantile onset MNK is poor, with most children dying by age three.

TREATMENT

Treatment of MNK is symptomatic and supportive. Early treatment with copper may improve the prognosis in some affected individuals.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment;

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  Laboratory findings;

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  Computed tomography (CT) and magnetic resonance imaging (MRI) showing white matter demyelination, lesions, atrophy, and evidence of rupture or blockage of the arteries; and

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  Developmental assessment or psychological testing to address allegations of mental impairments may be warranted.

Suggested Listings for Evaluation:

DETERMINATION

LISTING

REMARKS

Meets

110.08 B

Listing level neuro-cognitive findings must be documented; diagnosis of MNK or genetic laboratory testing results alone does not meet listing severity.

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