Methylmalonic Acidemia MMA

Disease Overview

Methylmalonic Acidemia (MMA) is a rare, inherited metabolic disorder characterized by the body's inability to properly metabolize certain amino acids, proteins, and fats. This genetic condition leads to the accumulation of methylmalonic acid in bodily fluids and tissues, potentially causing severe metabolic complications.

Disease Category

Metabolic Disorder - Subtype: Organic Acidemia - Classification: Inherited Metabolic Disorder

Synonyms

• Methylmalonic Aciduria
• MMA
• Methylmalonic Acidemia
• Cobalamin Metabolism Disorder

Signs & Symptoms

Acute and Chronic Symptoms: - Metabolic Crisis Symptoms - Severe vomiting - Dehydration - Lethargy - Metabolic acidosis

• Neurological Symptoms

  • Seizures
  • Developmental delays
  • Intellectual disability
  • Hypotonia (low muscle tone)

• Systemic Symptoms

  • Failure to thrive
  • Hepatomegaly (enlarged liver)
  • Renal failure
  • Cardiomyopathy
  • Growth retardation

Causes

Genetic Etiology: - Autosomal recessive inheritance - Mutations in genes responsible for protein metabolism: - MUT gene - MMAA gene - MMAB gene - MMADHC gene - MCEE gene

Affected Populations

• Prevalence: Approximately 1 in 50,000 to 1 in 100,000 live births
• Equally affects males and females
• Higher incidence in populations with increased consanguinity
• Typically diagnosed in infancy or early childhood

Disorders with Similar Symptoms

• Propionic Acidemia
• Isovaleric Acidemia
• Maple Syrup Urine Disease
• Urea Cycle Disorders
• Phenylketonuria (PKU)
• Glutaric Acidemia Type I and II

Diagnosis

Diagnostic Approaches: - Newborn Screening - Comprehensive Metabolic Panel - Genetic Testing - Urine Organic Acid Analysis - Blood Amino Acid Profiling - Imaging Studies (MRI/CT)

Standard Therapies

• Dietary Management
  • Low-protein diet
  • Specialized metabolic formula
• Vitamin B12 Supplementation
• Carnitine Supplementation
• Emergency Metabolic Protocol
• Medications to manage symptoms
• Potential Organ Transplantation (liver/kidney)

Clinical Trials and Studies

• Ongoing research in:
  • Gene therapy
  • Metabolic pathway interventions
  • Long-term treatment strategies
• Active clinical trials available on ClinicalTrials.gov

References

• National Institutes of Health (NIH)
• Genetic and Rare Diseases Information Center
• Journal of Inherited Metabolic Disease

Programs & Resources

• Genetic and Rare Diseases Information Center (GARD)
• National Organization for Rare Disorders (NORD)
• Organic Acidemia Association
• Metabolic Support UK

Complete Report

Methylmalonic Acidemia is a complex genetic metabolic disorder requiring comprehensive, lifelong management. Early diagnosis, specialized dietary interventions, and ongoing medical monitoring are critical for improving patient outcomes and quality of life.