Combined malonic and methylmalonic aciduria (CMAMMA), also called combined malonic and methylmalonic acidemia is an inherited metabolic disease characterized by elevated levels of malonic acid and methylmalonic acid.[1] Some researchers have hypothesized that CMAMMA might be one of the most common forms of methylmalonic acidemia, and possibly one of the most common inborn errors of metabolism.[2] Due to being infrequently diagnosed, it most often goes undetected.[2] [3]