Program Operations Manual System (POMS)
TN 34 (08-20)
DI 23022.191 Hoyeraal-Hreidarsson Syndrome
COMPASSIONATE ALLOWANCES INFORMATION
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HOYERAAL-HREIDARSSON SYNDROME |
ALTERNATE NAMES
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Hoyeraal-Hreidarsson Disease; Cerebellar Hypoplasia with Pancytopenia; Progressive
Pancytopenia Immunodeficiency Cerebellar Hypoplasia
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DESCRIPTION
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Hoyeraal-Hreidarsson Syndrome (HHS) is a severe X-linked multi-system disorder caused by mutations in the DKC1 gene.
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DIAGNOSTIC TESTING, PHYSICAL FINDINGS, AND
ICD-9-CM/ICD-10-CM
CODING
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Diagnostic testing:
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Neuroimaging reports showing cerebellar hypoplasia/atrophy, small brainstem, thin
corpus callosum and cerebral calcifications; and
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Genetic testing for the DKC1.
Physical
findings: Individuals with HHS are at risk for:
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Delays in intrauterine growth;
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Spastic paresis (weakness or partial loss of voluntary movement);
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Ataxia (impaired coordination);
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Progressive bone marrow failure;
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Myelodysplastic syndrome or acute leukemia;
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Solid tumors of the head/neck;
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Hyperpigmentation (darkened patches or spots on the skin) of upper chest/neck;
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Oral and premalignant leukoplakia affecting oral and gastrointestinal mucosa;
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Bilateral exudative retinopathy; and
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Intracranial calcifications.
ICD-9: 284; 287.33
ICD-10: D61
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PROGRESSION
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HHS usually presents in early childhood and primarily affects males (X-linked disorder).
The prognosis is poor due to the severity of the disease course. Progressive bone
marrow failure occurs in over 80% of cases and is the primary cause of early mortality.
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TREATMENT
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There is no cure for this disorder. Treatment is symptom specific and supportive.
Aplastic anemia and immunodeficiency are treated with bone marrow/stem cell transplantation.
Supportive treatment for gastrointestinal complications and infections is required.
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SUGGESTED PROGRAMMATIC ASSESSMENT*
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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 studies including results of genetic testing; and
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Suggested Listings for
Evaluation: |
DETERMINATION
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LISTING
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REMARKS
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Meets |
7.02
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7.06
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7.10
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7.17
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11.17
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111.17
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Equals |
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* Adjudicators may, at their discretion, use the Medical Evidence of Record or the
listings suggested to evaluate the claim. However, the decision to allow or deny the
claim rests with the adjudicator.
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