Table 3 Overview of all 13 treatable IEMs presenting as CP mimics identified by clinical experts on our team
Biochemical category | Disease name | OMIM# | Gene(s) | Treatment | Effect | Level of evidence |
|---|---|---|---|---|---|---|
Amino acids | PSAT deficiency | 610992 | PSAT1 (AR) | L-serine & +/−glycine supplements | Primary/targeting underlying pathophysiology | 4 |
|  | PSPH deficiency (Serine deficiency) | 614023 | PSPH (AR) | L-serine & +/−glycine supplements | Primary/targeting underlying pathophysiology | 4 |
Creatine | Arginine:glycine amidinotransferase (AGAT) deficiency | 612718 | GATM (AR) | Creatine supplements | Primary/targeting underlying pathophysiology | 4 |
| Â | Creatine transporter deficiency | 300352 | SLC6A8 (X-linked) | Creatine, glycine, arginine supplements | Primary/targeting underlying pathophysiology | 4 |
Fatty acid oxidation | Carnitine palmitoyltransferase I deficiency | 255120 | CPT1A (AR) | Low-fat, high carbohydrate diet, avoid fasting, Medium Chain Triglyceride oil | Stablizilng/preventative treatment | 4 |
Hyperhomocystinuria | Cobalamin deficiencies (e.g., C, D, E, F, G) | 251110, 277400, 277410, 236270, 277380 | MMACHC, MMADHC, MTRR, LMBRD1, MTR (AR) | Hydroxy-/cyanocobalamin (+/− diet restriction, betaine, B12) | Stabilizing/preventative treatment | 4 |
Lipid storage (Leukodystrophy) | Cerebrotendinous xanthomatosis (CTX) | 213700 | CYP27A1 (AR) | Chenodeoxycholic acid | Stabilizing/preventative treatment | 4 |
Organic acids | HMG-CoA lyase deficiency | 246450 | HMGCL (AR) | Protein restriction, avoid fasting, emergency regimen | Stabilizing/preventative treatment | 4-5 |
|  | mHMG-CoA synthase deficiency | 605911 | HMGCS2 (AR) | Avoid fasting,emergency regimen, +/−dietary precursor restriction | Stabilizing/preventative treatment | 5 |
| Â | SCOT deficiency | 245050 | OXCT1 (AR) | Avoid fasting, protein restriction, emergency regimen | Stabilizing/preventative treatment | 5 |
Urea cycle | Carbamoyl phosphate synthetase (CPS) deficiency | 237300 | CPS1 (AR) | Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (Liver transplantation) | Stabilizing/preventative treatment (primary/targeting underlying pathophysiology) | 2b (4) |
| Â | Citrullinemia type I (ASS deficiency) | 215700 | ASS1 (AR) | Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (Liver transplantation) | Stabilizing/preventative treatment (primary/targeting underlying pathophysiology) | 2b (4) |
| Â | N-acetyl-glutamate synthetase deficiency | 237310 | NAGS (AR) | Dietary protein restriction, arginine supplement, sodium benzoate, phenylbutyrate (Liver transplantation) | Stabilizing/preventative treatment | 4 |