PMC2774578_01
Serum glucose, total and direct (conjugated) bilirubin levels from birth to 3 (1/2) months of age.  Treatment of hyperglycemia detailed above graph.  Insulin infusion doses expressed in units/kg/hour.
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fig1
At birth, he suffered from respiratory distress and hypotension.  His initial blood glucose was 4.8 mmol/L, but when switched from oral to parenteral nutrition (at a glucose infusion rate of 3.6 mg/kg/min) on day of life 2, his blood glucose rose to greater than 11 mmol/L (Figure 1).   He required several insulin boluses during the first week of life, and a constant infusion of regular insulin (at 0.05 units/kg/hour) was started on day of life 7.  As detailed in Figure 1, his requirement for insulin was extremely variable. Because KCNJ11 mutations that cause NDM sometimes respond to sulfonylurea treatment, at 14 weeks of age, glipizide was added to his insulin therapy at 0.15 mg/kg/day and increased to 0.75 mg/kg/day over a 4-day period.  Upon initiation of glipizide treatment, his insulin dose was halved (0.03 to 0.015  units/kg every 3 hours as needed for blood glucoses > 11 mmol/L), and he required one to three insulin injections per day (Figure 1). At 2 months of age (corrected age 34.5 weeks), the patient developed liver dysfunction (Figure 1, Table 2).  Of note, at this time he had been off of parental nutrition for over one month. 
DNA sequence of KCNJ11 from the patient. Substitution of G for A at nucleotide 155 (c.155A>G) results in Arginine (R) instead of Glutamine (Q) at amino acid 52 (Q52R).
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fig2
Further testing, however, revealed a heterozygous mutation in the KCNJ11 gene (c.155A>G, Q52R, Figure 2) which was not present in his parents or twin sister. At 2 months of age (corrected age 34.5 weeks), the patient developed liver dysfunction (Figure 1, Table 2).  Of note, at this time he had been off of parental nutrition for over one month. 