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Homocystinuria due to cystathionine beta synthase deficiency
T Narayana Rao1, K Radhakrishna, T S Mohana Rao
1Department of Dermatology, Andhra Medical College, Visakhapatnam, Andhra Pradesh, India. tnr_derma@yahoo.com
Indian Journal of Dermatology, Venereology and Leprology
|September 18, 2008
Summary
This case report details a rare instance of homocystinuria in a child, successfully treated with pyridoxine. Early intervention with vitamin B6 improved neurological and skin symptoms, highlighting its therapeutic potential.
Area of Science:
- Biochemistry
- Genetics
- Pediatrics
Background:
- Homocystinuria is an inherited metabolic disorder caused by cystathionine beta-synthase (CBS) deficiency.
- It leads to elevated homocysteine and methionine levels, affecting multiple organ systems.
- Phenotypic manifestations can resemble Marfan syndrome, including connective tissue, vascular, and neurological abnormalities.
Observation:
- A two-year-old male presented with cutis marmorata congenita universalis, brittle hair, mild intellectual disability, and finger spasms.
- Elevated blood homocysteine levels (106.62 µmol/L) and positive nitroprusside tests indicated homocystinuria.
- Cutaneous findings included generalized cutis marmorata, thin hair, and malar flush.
Findings:
- The patient received oral pyridoxine (vitamin B6) therapy for three months.
- Significant improvement was observed, with subsidence of muscle spasms and skin manifestations.
- Pyridoxine therapy demonstrated efficacy in managing the symptoms of this rare condition.
Implications:
- This case underscores the importance of early diagnosis and treatment of homocystinuria.
- Pyridoxine therapy can effectively ameliorate neurological and dermatological symptoms associated with CBS deficiency.
- Reporting rare cases aids in understanding the diverse clinical spectrum and therapeutic responses in metabolic disorders.
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