Lactate and pyruvate levels in blood and cerebrospinal fluid in patients with Menkes disease.

OBJECTIVE: To examine levels of lactate (LA) and pyruvate (PA) in both blood and cerebrospinal fluid (CSF) in patients with Menkes disease (MNK). STUDY DESIGN: A nationwide survey involving a retrospective review of medical records or medical record summaries of 42 male patients with MNK born between 1993 and 2008 were performed, and the genetic analysis of their ATP7A gene was reviewed. RESULTS: In these patients, LA and PA levels and the lactate vs pyruvate ratio (L/P ratio) at diagnosis in both blood and CSF were abnormally high. There were no significant differences in LA levels, PA levels, and the L/P ratio between blood and CSF at diagnosis (P > .05). There was also no correlation between LA levels, PA levels, and the L/P ratio, and age at measurement (P > .05). There was no or slight metabolic acidosis, as analyzed by blood gas analysis, in 7 patients. During treatment with subcutaneous injections of copper-histidine, LA and PA levels and the L/P ratio in both the blood and CSF decreased. CONCLUSION: Our findings suggest that LA and PA levels, and in particular, the L/P ratio, and blood gas analysis can be used to guide the diagnosis and management of MNK.

Hypothyroidism caused by iodine deficiency and iodine levels in enteral formulas.

BACKGROUND: A 4-year-old female patient was diagnosed with hypothyroidism caused by iodine deficiency. The patient's iodine levels in serum and urine were significantly low. The iodine concentration in the enteral formula was 1.6 µg/100 kcal as measured by inductively coupled plasma mass spectrometry. The patient's iodine intake while receiving the enteral formula was calculated to be 16 µg/day, which is much lower than the recommended dietary reference intake of 80 µg for children aged 3-5 years. The purpose of this study was to assess iodine concentrations in 20 enteral nutritional formulas available in Japan in order to assess whether low iodine concentration is a characteristic of one specific formula or whether it is a more prevalent problem. METHODS: Iodine concentrations in 20 popular nutritional formulas available in Japan, for which iodine content is not indicated in the ingredient list, were analyzed with inductively coupled plasma mass spectrometry. RESULTS: Iodine concentrations were less than 5 µg/100 kcal and less than 10 µg/100 kcal in 13 and 18 enteral nutritional formulas, respectively. CONCLUSIONS: Most of the enteral nutritional formulas analyzed had low iodine concentrations. These findings suggest that iodine deficiency is a likely outcome in patients who receive these formulas for a prolonged period.