Diabetic ketoalkalosis in children and adults.

OBJECTIVES: Diabetic ketoacidosis (DKA) with metabolic alkalosis (diabetic ketoalkalosis [DKALK]) in adults has been described in the literature, but not in the pediatric population. The discordance in the change in the anion gap (AG) and the bicarbonate is depicted by an elevated delta ratio (DR; rise in AG/drop in bicarbonate), which is normally approximately 1. The primary aim of this study was to determine whether DKALK occurs in the pediatric population, as has been seen previously in the adult population. The secondary aim was to determine the factors that may be associated with DKALK. METHODS: A retrospective analysis of adult and pediatric cases with a primary or secondary discharge diagnosis of DKA between May 2008 and August 2010 at a large urban hospital was performed. DKALK was assumed to be present if the DR was >1.2 or in cases of elevated bicarbonate. RESULTS: Of 190 DKA cases, 91 were children, with 21% fulfilling the criterion for DKALK. There were 99 adult cases, 35% of which fulfilled the criterion for DKALK. Our final logistic model revealed that among patients with a discharge diagnosis of DKA, male patients, patients with a history of renal failure, and patients presenting with abdominal findings on physical examination were at greater odds of having a concomitant metabolic alkalosis. CONCLUSIONS: Although DKALK has been described in adults, it can occur in a significant number of children presenting with DKA. The recognition of DKA can be obscured in such situations unless the AG and DR are calculated because the pH and bicarbonate may be near normal or even elevated. In addition to having interesting biochemical features as a complex acid-base disorder, DKALK can pose diagnostic and/or therapeutic challenges.

Reliability and validity of the Mywellness Key physical activity monitor.

BACKGROUND: This study evaluated the reliability and criterion validity of the Mywellness Key accelerometer (MWK) using treadmill protocols and indirect calorimetry. METHODS: Twenty-five participants completed two four-stage 20-minute treadmill protocols while wearing two MWK accelerometers. Reliability was assessed using raw counts. Validity was assessed by comparing the estimated VO(2) calculated from the MWK with values from respiratory gas exchange. RESULTS: Good overall and point estimates of reliability were found for the MWK (all intraclass correlations > 0.93). Generalizability theory coefficients showed lower values for running speed (0.70) versus walking speed (all > 0.84), with the majority of the overall percentage of variability derived from the participant (68%-88% of the total 100%). Acceptable validity was found overall (Pearson's r = 0.895-0.902, P < 0.0001), with an overall mean absolute error of 16.22% and a coefficient of variance of 16.92%. Bland-Altman plots showed an overestimation of energy expenditure during the running speed, but total kilocalories were underestimated during the protocol by approximately 10%. CONCLUSION: Good validity was found during light and moderate walking, while running was slightly overestimated. The MWK may be useful for clinicians and researchers interested in promotion or assessment of physical activity.

Serum carnitine levels and levocarnitine supplementation in institutionalized Huntington's disease patients.

Along with antioxidant properties, carnitine is an important regulator of lipid metabolism in humans. While beneficial effects of carnitine have been demonstrated in animal models of Huntington's disease (HD), metabolism of carnitine has not been studied in humans with this illness. In this retrospective database review from 23 patients admitted to a HD-specialized nursing home unit, we found a relatively high prevalence of hypocarnitinemia (6 cases, 26%). Our review suggests that catabolism and chronic valproate use predisposed our patients to develop hypocarnitinemia. The patients with low serum carnitine levels who received levocarnitine supplementation, during a mean period of 7.3 months, showed improvement in motor, cognitive and behavioral measures. We hypothesize that observed improvement related to the resolution of reversible metabolic encephalopathy and myopathy associated with secondary carnitine deficiency. In conclusion, notwithstanding its limitations, this is the first study to report measurements of carnitine levels in HD patients, revealing relatively high prevalence of hypocarnitinemia in our population. Our findings suggest that HD patients with hypocarnitinemia may benefit from low-dose levocarnitine supplementation. Further studies of carnitine metabolism and supplementation in HD patients are warranted.

Carnitine and metabolic correlates in hospitalized psychiatric patients: a follow-through report.

BACKGROUND: Carnitine deficiency may be encountered in the context of chronic psychiatric illness, particularly with the chronic use of valproic acid. Despite the importance of carnitine in lipid metabolism and mitochondrial function, its metabolic effects have not been studied in a psychiatric population. OBJECTIVE: To raise awareness regarding the possible metabolic implications of carnitine homeostasis in psychiatric patients. METHOD: Retrospective database review in a subgroup of 23 patients with documented hypo carnitinemia. RESULTS: Statistical analysis revealed a negative correlation between serum carnitine levels and lipid levels. Initial fasting plasma glucose levels correlated positively with acylcarnitine/free carnitine ratios, suggesting unfavorable secondary effects of carnitine insufficiency, which resolved once carnitine was supplemented. CONCLUSION: Carnitine is a plausible substrate for future investigations of metabolic status in psychiatric patients. Further studies are needed to evaluate whether serum carnitine levels may be useful as a marker for psychiatric patients at risk for developing metabolic syndrome, and whether carnitine supplementation may reduce that risk. (Journal of Psychiatric Practice 2011;17:35-40).

Clinical correlates of low serum carnitine levels in hospitalized psychiatric patients.

OBJECTIVE: We sought to evaluate clinical correlates of low serum carnitine levels in hospitalized psychiatric patients. METHODS: We retrospectively reviewed the charts of 40 psychiatric inpatients identified to have low serum carnitine levels. RESULTS: Cognitive impairment was present in 38 (95%) cases, frequently accompanied by imbalance, agitation and extrapyramidal symptoms. Valproate therapy was encountered in 28 (70%) patients. The dosage of valproate negatively correlated with total and free carnitine levels (P = 0.003 and 0.0136). Polypharmacy also affected carnitine levels, indicating additional modulatory effects on carnitine metabolism. We encountered a disproportionately high prevalence of mental retardation and dementia in association with hypocarnitinemia. CONCLUSION: We hypothesize that in the context of mental illness hypocarnitinemia may be associated with metabolic encephalopathy and cognitive impairment. As carnitine deficiency is a potentially treatable condition further studies are warranted.

Clinical outcomes and low-dose levocarnitine supplementation in psychiatric inpatients with documented hypocarnitinemia: a retrospective chart review.

BACKGROUND: Metabolic encephalopathy is one of the crucial manifestations of carnitine deficiency. In psychiatric patients, low serum carnitine levels may result from chronic valproate therapy. Despite the widespread use of valproate in psychiatry, neither carnitine deficiency nor supplementation has been studied in a psychiatric population. OBJECTIVE: To describe clinical outcomes in hospitalized psychiatric patients with documented hypocarnitinemia who were receiving oral levocarnitine supplementation. METHOD: Retrospective chart review. RESULTS: In 38 patients with hypocarnitinemia, a low-dose oral levocarnitine supplementation, in association with comprehensive psychiatric therapy, did not result in any adverse psychiatric or medical outcomes, and was associated with overall improved behavioral, cognitive, and motor functioning. Initially all patients had some degree of cognitive impairment, but after correction of carnitine serum levels, scores on the Mini-Mental State Examination (MMSE) improved in most of the patients (mean improvement 5.5 points, P <0.0001), and normalized in 11 cases. This allowed a correction of the diagnosis in 8 of 14 patients who had initially been diagnosed with dementia. African-American patients achieved significantly lower serum carnitine levels and MMSE scores than Caucasian patients with comparable therapy. CONCLUSION: We hypothesize that correction of carnitine depletion, either by levocarnitine supplementation or by valproate dose reduction, may enhance recovery from hypocarnitinemia-associated encephalopathy in psychiatric patients. Our findings also suggest that ethnic traits may affect carnitine bioavailability as well as cognitive outcomes in this clinical context. Further studies of carnitine metabolism and supplementation in psychiatric patients are warranted.

Clinical outcomes of antimicrobial lock solutions used in a treatment modality: a retrospective case series analysis.

BACKGROUND: Antimicrobial lock therapy (ALT) may be considered as adjunctive therapy in the treatment of catheter-related bloodstream infections (CRBSI) when catheter removal is not a favorable option. OBJECTIVE: To evaluate the outcomes associated with ALT as adjunctive treatment of CRBSI. METHODS: This was a 24-month retrospective case series analysis evaluating patients treated for more than 24 hours with ALT. The primary outcome was blood culture sterilization for 30 days posttherapy. The impact of ALT duration and time to initiation on central venous catheter (CVC) salvage were evaluated. Logistic regression modeled the association between ALT and sterilization rates, with a prespecified level of significance (α) of 0.1. RESULTS: Twenty-six cases were included in data analysis. Patients included ranged from 5 months to 82 years of age; 77% of patients were receiving total parenteral nutrition or chemotherapy. The majority of patients received vancomycin, daptomycin, or gentamicin combined with heparin in a lock solution. Blood culture sterilization was achieved in 69.2% of cases, and sterilization plus CVC retention was achieved in 11 cases (42.3%). Longer durations of ALT (≥9 days) were significantly correlated with blood culture sterilization (odds ratio = 1.367, P = 0.077). CONCLUSION: ALT used as an adjunct to systemic therapy for adequate duration in CRBSI can achieve CVC sterilization and retainment without subsequent infectious complications.