Table 2.

Biochemical analysis of our patient and those reported with DLD deficiency

Case	Enzyme Activity (%)					Biochemical Tests
	PDH	BCKDH	αKGDH	DLD	Tissue Type	Plasma Amino Acids				Urine Organic Acids
						BCAA	Glutamine	Alloisoleucine	Alanine	Lactate	αKG	Other
1											+
2	63	56	0	20	F						+	Succinic, fumaric, malic
3			0	20	F							Fumaric
4				20	M					+		Ketones
				18	L
5	0		15	2	M							Branched chain keto acids
6				8	M				+	+	+	Ketones, α-ketoadipic
				9	L
7	12		6	3	F	+			+	+	+	Succinic, hydroxyisovaleric, isocaproic
	14		1	11	M
	13			9	L
8				8	F
9				16	F
10				30	F
11	13–97			0	F	+					+
12						+	+			+	+	Ketones, branched chain keto acids
13				33	F
14	59	62	25	9	F				+	+	+	Ketones
15				12	L
16				9	M	+	+		+			Ketones, α-aminoadipic, α-ketoadipic, α-hydroxyadipic
				13–31	L
17				8	M
				17	L
18				19	L
19				21	M	+				+	+	Ketones
				18	L
20	69	58	44	10	F	+				+	+	Ketones, DCAs
21	5–44			4–14	F	+				+		Branched chain acids
	3–14			3–6	M
	5–38			3–12	L
22				6	F	+				+	+	Branched chain keto acids
23	11		20	14	F	+		+		+
	26			1.5	L
24*	80	24	107	9–29	F	+	+	+		+	+	Hydroxyglutaric, ketones, hydroxyisovaleric, succinic
25	100				F	+	+	+		+		Branched chain oxoacids, ketones, 2-hydroxyglutaric acid
	14			29	M

^*, our patient (in bold); F, fibroblasts; M, muscle; and L, lymphocytes. Please see Table 1 for references corresponding to each case. PDH, pyruvate dehydrogenase; BCKDH, branched chain ketoacid dehydrogenase; αKGDH, alpha-ketoglutrate dehydrogenase; DLD, dihydrolipoamide dehydrogenase; BCAA, branched chain amino acids; Gln, glutamine; αKG, alpha-ketoglutarate; DCA, dicarboxylic acids