Journal of Inherited Metabolic Disease

, Volume 35, Issue 1, pp 103–114

Combined methylmalonic acidemia and homocystinuria, cblC type. II. Complications, pathophysiology, and outcomes

Review

DOI: 10.1007/s10545-011-9365-x

Cite this article as:
Carrillo-Carrasco, N. & Venditti, C.P. J Inherit Metab Dis (2012) 35: 103. doi:10.1007/s10545-011-9365-x

Abstract

Combined methylmalonic acidemia and homocystinuria, cblC type, is stated to be the most common inborn error of intracellular cobalamin metabolism. The disorder can display a wide spectrum of clinical manifestations, spanning the prenatal period through late adulthood. While increased homocysteine concentrations and impaired methyl group metabolism may contribute to disease-related complications, the characteristic macular and retinal degeneration seen in many affected patients appears to be unique to cblC disease. The early detection of cblC disease by newborn screening mandates a careful assessment of therapeutic approaches and provides a new opportunity to improve the outcome of affected patients. The following article reviews the current knowledge on the complications, pathophysiology, and outcome of cblC disease in an effort to better guide clinical practice and future therapeutic trials.

Abbreviations

cblC

Cobalamin C disease

CBS

Cystathionine beta synthase

CNCbl

Cyanocobalamin

IM

Intramuscular

MeCbl

Methylcobalamin

MMA

Methylmalonic acid

MTHFR

Methylenetetrahydrofolate reductase

OHCbl

Hydroxocobalamin

SAM

S-Adenosylmethionine

SCD

Subacute combined degeneration of the spinal cord

tHcy

Total plasma homocysteine

HcyTL

Homocysteine thiolactone

Supplementary material

10545_2011_9365_MOESM1_ESM.docx (192 kb)
Supplementary Table 1Ophthalmologic complications in patients with cblC disease (DOCX 191 kb)
10545_2011_9365_MOESM2_ESM.docx (160 kb)
Supplementary Table 2Outcome of patients with cblC disease and their therapeutic regimens (DOCX 159 kb)

Copyright information

© SSIEM and Springer (outside the USA) 2011

Authors and Affiliations

  1. 1.Organic Acid Research Section, Genetics and Molecular Biology Branch, National Human Genome Research InstituteNational Institutes of HealthBethesdaUSA