eMedicine Specialties > Pediatrics: Genetics and Metabolic Disease > Metabolic Diseases
Methylmalonic Acidemia: Follow-up
Updated: Jul 7, 2008
Follow-up
Further Outpatient Care
- Depending on age and metabolic control, follow up in regular intervals (eg, 1-4 follow-up visits or more per y) with a biochemical geneticist familiar with the management of methylmalonic acidemia (MMA).
Inpatient & Outpatient Medications
- L-carnitine (100-300 mg/kg orally [PO], divided 3 times daily [tid])
- Hydroxocobalamin/cyanocobalamin: Hydroxocobalamin is by far more effective than cyanocobalamin. Administer hydroxocobalamin (1 mg/d intramuscularly [IM]) only to patients with cobalamin-responsive forms of MMA.
- Metronidazole: Administer metronidazole (10-20 mg/kg PO divided tid) or neomycin (50 mg/kg PO, divided tid) to reduce gut propionate production. Administer a limited trial with metronidazole (1-2 mo).
- Betaine
- Children younger than 3 years require 100 mg/kg PO divided twice daily (bid).
- Children older than 3 years require 250 mg/kg PO divided bid.
- Adults require 250 mg/kg PO divided bid.
- Some patients require amounts up to 20 g/d. Consider this dosage as nonspecific therapy for patients with combined MMA and homocystinuria to reduce plasma homocysteine levels.
- Folate
- Infants require 15 mcg/kg/d or 50 mcg/d.
- Children require 1 mg/d initial dose, then 0.1-0.3 mg/d.
- Adults require 1 mg/d initial dose, then 0.5 mg/d (for patients with combined MMA and homocystinuria to reduce plasma homocysteine levels).
Transfer
- Treat children with MMA only at tertiary care facilities that have access to a multidisciplinary team of biochemical geneticists, dietitians, neonatologists, and other medical specialists.
Prognosis
- Prognosis depends on the type of MMA and whether the patient's condition is well controlled (ie, in general and during episodes of metabolic decompensation).
Patient Education
- Educate caregivers about how to identify and respond to episodes of metabolic decompensation in patients with MMA. Supply a written emergency regimen and card.
Miscellaneous
Medicolegal Pitfalls
- Methylmalonic acidemia (MMA) is difficult to diagnose because of nonspecific symptoms at presentation.
- A family history that is positive for MMA should alert the physician to the likelihood of an underlying organic aciduria.
- In any neonate presents with vomiting, lethargy, and failure to thrive during the first days of life, MMA must be ruled out despite the presence of newborn screening programs.
More on Methylmalonic Acidemia |
| Overview: Methylmalonic Acidemia |
| Differential Diagnoses & Workup: Methylmalonic Acidemia |
| Treatment & Medication: Methylmalonic Acidemia |
Follow-up: Methylmalonic Acidemia |
| References |
| « Previous Page |
References
Oberholzer VG, Levin B, Burgess EA, Young WF. Methylmalonic aciduria. An inborn error of metabolism leading to chronic metabolic acidosis. Arch Dis Child. Oct 1967;42(225):492-504. [Medline].
Stokke O, Jellum E, Eldjarn L, Schnitler R. The occurrence of beta-hydroxy-n-valeric acid in a patient with propionic and methylmalonic acidemia. Clin Chim Acta. May 30 1973;45(4):391-401. [Medline].
Coulombe JT, Shih VE, Levy HL. Massachusetts Metabolic Disorders Screening Program. II. Methylmalonic aciduria. Pediatrics. Jan 1981;67(1):26-31. [Medline].
Lerner-Ellis JP, Tirone JC, Pawelek PD, et al. Identification of the gene responsible for methylmalonic aciduria and homocystinuria, cblC type. Nat Genet. Jan 2006;38(1):93-100. [Medline].
Acquaviva C, Benoist JF, Pereira S, et al. Molecular basis of methylmalonyl-CoA mutase apoenzyme defect in 40 European patients affected by mut(o) and mut- forms of methylmalonic acidemia: identification of 29 novel mutations in the MUT gene. Hum Mutat. Feb 2005;25(2):167-76. [Medline].
Andersson HC, Shapira E. Biochemical and clinical response to hydroxocobalamin versus cyanocobalamin treatment in patients with methylmalonic acidemia and homocystinuria (cblC). J Pediatr. Jan 1998;132(1):121-4. [Medline].
Caksen H, Atas B, Tuncer O, Odabas D. Severe generalized dystonia induced by metoclopramide in a girl with methylmalonic acidemia. Brain Dev. Mar 2003;25(2):144-5. [Medline].
Dobson CM, Wai T, Leclerc D, et al. Identification of the gene responsible for the cblA complementation group of vitamin B12-responsive methylmalonic acidemia based on analysis of prokaryotic gene arrangements. Proc Natl Acad Sci U S A. Nov 26 2002;99(24):15554-9. [Medline].
Fenton WA, Rosenberg LE. Disorders of propionate and methylmalonate metabolism. In: Scriver CR, Beaudet AL, Sly WS, Valle DL, eds. The Metabolic and Molecular Bases of Inherited Disease. New York, NY: McGraw-Hill Co; 1995:1423-49.
Fowler B. Genetic defects of folate and cobalamin metabolism. Eur J Pediatr. Apr 1998;157 Suppl 2:S60-6. [Medline].
Huemer M, Simma B, Fowler B, et al. Prenatal and postnatal treatment in cobalamin C defect. J Pediatr. Oct 2005;147(4):469-72. [Medline].
Morel CF, Watkins D, Scott P, et al. Prenatal diagnosis for methylmalonic acidemia and inborn errors of vitamin B12 metabolism and transport. Mol Genet Metab. Sep-Oct 2005;86(1-2):160-71. [Medline].
Nyhan WL. Methylmalonic acidemia. In: Atlas of Metabolic Diseases. New York, NY: Chapman & Hall Medical; 1998:13-23.
Ostergaard E, Wibrand F, Orngreen MC, et al. Impaired energy metabolism and abnormal muscle histology in mut- methylmalonic aciduria. Neurology. Sep 27 2005;65(6):931-3. [Medline].
Rosenblatt DS, Whitehead VM. Cobalamin and folate deficiency: acquired and hereditary disorders in children. Semin Hematol. Jan 1999;36(1):19-34. [Medline].
Tanpaiboon P. Methylmalonic acidemia (MMA). Mol Genet Metab. May 2005;85(1):2-6. [Medline].
Worgan LC, Niles K, Tirone JC, et al. Spectrum of mutations in mut methylmalonic acidemia and identification of a common Hispanic mutation and haplotype. Hum Mutat. Jan 2006;27(1):31-43. [Medline].
Further Reading
Keywords
methylmalonic acidemia, MMA, methylmalonic aciduria, methylmalonic acid, propionic acidemia, lethargy, hypoglycemia, seizures, progressive myopathy, lower leg hyposensitivity, thrombosis, retinopathy, nystagmus, reduced visual acuity, hydrocephalus, microcephaly, dehydration, failure to thrive, developmental delay, choreoathetosis, dystonia, dysphagia, dysarthria
Follow-up: Methylmalonic Acidemia