Table 2.
Positive acylcarnitine results in patients with mitochondrial fatty acid oxidation defects and organic acidurias
| Ratio (100 x acylcarnitine/acetyl carnitine) in earwax from patients with mitochondrial fatty acid oxidation defects | ||||||
|---|---|---|---|---|---|---|
| Patient | Earwax hydroxyhexadecenoylcarnitine ratio | Earwax hydroxyhexadecanoylcarnitine ratio | Earwax hydroxyoctadecenoylcarnitine ratio | Matching bloodspot hydroxyhexadecenoylcarnitine μmol/L (normal <0.09 μmol/L)a | Matching bloodspot hydroxyhexadecanoylcarnitine μmol/L (normal <0.09 μmol/L)a | Matching bloodspot hydroxyoctadecenoylcarnitine μmol/L (normal <0.09 μmol/L)a |
| LCHADDa | 6.17 ↑ ↑ | 10.89 ↑ ↑ | 9.48 ↑ ↑ | 0.18 ↑ | ND | 0.14 ↑ |
| LCHADDb | 3.51 ↑ | 7.59 ↑ ↑ | 2.28 ↑ | 0.28 ↑ | 0.14 ↑ | 0.30 ↑ |
| LCHADDc | 2.46 ↑ | 4.24 ↑ | 3.22 ↑ | 0.36 ↑ | 0.26 ↑ | 0.25 ↑ |
| Disease control range | 0.11‐1.84 | 0.24‐3.25 | 0.21‐1.44 | |||
| Ratio (100 x acylcarnitine/free carnitine) in earwax from patients with organic acid defects | ||||||
|---|---|---|---|---|---|---|
| Patient | Earwax Isovalerylcarnitine ratio | Matching bloodspot Isovalerylcarnitine μmol/L (normal <0.06 μmol/L) | Earwax propionylcarnitine ratio | Matching plasma methylmalonate μmol/L (normal <1.00 μmol/L) | ||
| IVAa | 15.8 ↑ ↑ | 10.0 ↑ ↑ | ||||
| IVAb | 12.8 ↑ ↑ | 21.1 ↑ ↑ | ||||
| MMAa | 9.2 ↑ | 31 ↑ | ||||
| Disease control range | 0.14‐2.72 | 0.27‐4.06 | ||||
a
In‐house established reference range.