A pilot study of serum free carnitine levels in hospitalized febrile children

Serum free carnitine levels in children with Kawasaki disease

BACKGROUND

Carnitine plays an essential role in the transfer of long-chain fatty acids to the mitochondria for β-oxidation. No study has characterized carnitine in children with Kawasaki disease (KD). The objective of this study was to elucidate the characteristics of serum free carnitine (FC) in hospitalized pediatric patients with KD.

METHODS

We retrospectively analyzed 45 patients with KD in whom serum FC levels were measured. We investigated the clinical and laboratory parameters before intravenous immunoglobulin was administered, including serum FC levels, according to the response to intravenous immunoglobulin (IVIG). We also analyzed the relationship among serum FC, laboratory data, and clinical variables.

RESULTS

IVIG was effective in 33 children (responders) and was ineffective in 12 children (non-responders). Serum FC levels were higher in non-responders than in responders: 35.3 μmol/L (range, 26.8-118.4 μmol/L) vs 31.4 μmol/L (range, 20.9-81.2 μmol/L), P <0.05. FC levels before IVIG in 80% of responders were below the normal range. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, and FC were higher in non-responders than in responders. FC levels were correlated with AST (R² = 0.364, P = 0.0015) and ALT (R² = 0.423, P < 0.001) levels.

CONCLUSIONS

Free carnitine levels were elevated in some patients with KD, especially in those who were refractory to IVIG. Additionally, FC levels in children with KD correlated with ASL and ALT levels.

Effects of l-carnitine supplementation in patients with childhood-onset epilepsy prescribed valproate

BACKGROUND

The benefits of carnitine supplementation in patients treated with valproate (VPA) are not clear. Therefore, we retrospectively explored the benefits of carnitine supplementation by analyzing laboratory data.

METHODS

We measured the serum-free carnitine (FC), VPA, aspartate aminotransferase, alanine aminotransferase, amylase, and ammonia levels, and the platelet count, in 69 patients with childhood-onset epilepsy treated with VPA. Eight patients had received carnitine supplementation. The serum FC and acylcarnitine levels were measured using an enzyme cycling method. We compared laboratory values between patients with and without carnitine supplementation and analyzed the correlations between serum FC levels and laboratory values.

RESULTS

The serum FC levels were normal (median, 48.8 μmol/L; range: 41.9-68.3 μmol/L) in all eight patients with carnitine supplementation, but below normal in 32 of 61 patients without supplementation. The median serum amylase levels were lower in the patients with carnitine supplementation (median, 48 U/L; range: 27-149 U/L) than in those without (median, 7 U/L; range: 14-234 U/L). The platelet count and serum ammonia levels did not differ significantly between patients with and without supplementation. There was no significant correlation between the serum FC level and the platelet count, serum amylase level, or ammonia level.

CONCLUSIONS

Carnitine supplementation helps maintain serum FC levels in patients treated with VPA. The lower serum amylase levels in patients with carnitine supplementation may reflect protective effects of carnitine against latent pancreatic injury.