Detection of surreptitious administration of analog insulin to an 8-week-old infant.

An 8-week-old infant presented to the emergency department with lethargy, tachycardia, and a blood glucose concentration of 1.8 mmol/L. After admission, hypoglycemia recurred on 3 additional occasions. Initial urinalysis results were negative for ketones, and the results of additional laboratory tests did not support the diagnosis of cortisol or growth hormone deficiency, oral hypoglycemic ingestion, or an inborn error of metabolism. Difficulty restoring and maintaining glucose concentrations along with a transient response to glucagon during 1 hypoglycemic episode suggested hyperinsulinism. In 1 hypoglycemic episode, elevated insulin and low C-peptide concentrations suggested exogenous insulin administration, but 2 subsequent blood samples obtained during hypoglycemia contained appropriately decreased concentrations of insulin. The insulin immunoassay initially used in this case (Roche ElecSys/cobas [Roche Diagnostics, Indianapolis, IN]) was insensitive to insulin analogs. Two additional immunoassays, 1 with intermediate (Immulite [Siemens, Deerfield, IL]) and 1 with broad (radioimmunoassay [Millipore, Inc, Billerica, MA]) reactivity to insulin analogs were used to characterize insulin in each of the critical blood samples. Samples obtained during hypoglycemia displayed a graded reactivity similar to that observed in type 1 diabetic patients prescribed insulin analogs, whereas a sample obtained from the patient and a control subject during euglycemia showed equal reactivity among the 3 assays. These data suggested administration of insulin analog to the child, and further characterization of insulin by using tandem mass spectrometry confirmed the presence of Humalog. The child was subsequently placed in foster care with no further recurrence of hypoglycemia.

Effect of long-term corticosteroid use on bone mineral density in children: a prospective longitudinal assessment in the childhood Asthma Management Program (CAMP) study.

OBJECTIVE: Systemic corticosteroids are known to induce osteoporosis and increase the risk for fractures in adults and children. Inhaled corticosteroids have been shown to increase the risk for osteoporosis and fractures in adults at risk; however, long-term prospective studies of children to assess risks of multiple short courses of oral corticosteroids and chronic inhaled corticosteroids have not been performed. Thus, we assessed the effects of multiple short courses of oral corticosteroids and long-term inhaled corticosteroids on bone mineral accretion over a period of years. METHODS: This was a cohort follow-up study for a median of 7 years of children who had mild-to-moderate asthma and initially were randomly assigned into the Childhood Asthma Management Program trial. Serial dual-energy radiograph absorptiometry scans of the lumbar spine for bone mineral density were performed for all patients. Annual bone mineral accretion was calculated for 531 boys and 346 girls who had asthma and were aged 5 to 12 years at baseline (84% of the initial cohort). RESULTS: Oral corticosteroid bursts produced a dosage-dependent reduction in bone mineral accretion (0.052, 0.049, and 0.046 g/cm(2) per year) and an increase in risk for osteopenia (10%, 14%, and 21%) for 0, 1 to 4, and >or=5 courses, respectively, in boys but not girls. Cumulative inhaled corticosteroid use was associated with a small decrease in bone mineral accretion in boys but not girls but no increased risk for osteopenia. CONCLUSIONS: Multiple oral corticosteroid bursts over a period of years can produce a dosage-dependent reduction in bone mineral accretion and increased risk for osteopenia in children with asthma. Inhaled corticosteroid use has the potential for reducing bone mineral accretion in male children progressing through puberty, but this risk is likely to be outweighed by the ability to reduce the amount of oral corticosteroids used in these children.

Home sodium monitoring in patients with diabetes insipidus.

OBJECTIVE: To determine whether home care givers can accurately measure plasma sodium in children with diabetes insipidus (DI) by using an I-STAT portable clinical analyzer (PCA) and to collect preliminary data on home PCA use. STUDY DESIGN: Care givers of 4 children with DI and impaired thirst or inability to access water freely were instructed in PCA use. During an initial preclinical phase, the accuracy of sodium concentration measured by care givers was assessed by comparison to simultaneous analysis in a clinical laboratory. Participants were subsequently randomly assigned to daily home PCA monitoring or routine care. All participants crossed over from their original randomized group assignment to the alternate group. RESULTS: After a single education session, all care givers were able to perform PCA testing. There was good correlation between PCA and laboratory sodium (r = 0.92). On the basis of Error Grid Analysis, use of the PCA sodium would have resulted in treatment decisions identical to those made based on the laboratory sodium value in 62 of 66 instances. Four minor differences in treatment would have occurred. There was no statistically significant difference in clinical outcome during daily monitoring versus routine care. CONCLUSIONS: Results obtained by care givers using the PCA are sufficiently reliable for assessment of fluid status and making treatment decisions.