Background Lipoprotein lipase (LPL) deficiency is a monogenic lipid metabolism disorder biochemically characterized by hypertriglyceridemia (HTG) inherited in an autosomal recessive manner. Neonatal onset LPL deficiency is rare. The purpose of this study was to clarify the clinical features of neonatal LPL deficiency and to analyze the genetic characteristics of LPL gene. Methods In order to reach a definite molecular diagnose, metabolic diseases-related genes were sequenced through gene capture and next generation sequencing. Meanwhile, the clinical characteristics and follow-up results of the two newborns were collected and analyzed. Results Three different mutations in the LPL gene were identified in the two newborns including a novel compound heterozygous mutation (c.347G > C and c.472 T > G) and a reported homozygous mutation (c.836 T > G) was identified. Interestingly, both the two neonatal onset LPL deficiency patients presented with suffered recurrent infection in the hyperlipidemia stage, which was not usually found in childhood or adulthood onset LPL deficiency patients. Conclusion The two novel mutaitons, c.347G > C and c.472 T > G, identified in this study were novel, which expanded the LPL gene mutation spectrum. In addition, suffered recurrent infection in the hyperlipidemia stage implied a certain correlation between immune deficiency and lipid metabolism abnormality. This observation further supplemented and expanded the clinical manifestations of LPL deficiency.

Objective:To investigate the effect of illness on preterm infant's hypothalamus-putituary-adrenal axis, we measured the concentration of cortisol, aldosterone and ACTH.Methods: Ninety preterm infants were divided into two groups: gestational age (GA) ≥ 34weeks' and GA< 34weeks'. We measured serum cortisol, aldosterone and ACTH within 72 hours after birth, day 7 and day 14. Results:(1) The serum cortisol concentration on severe illness was higher than that on mild illness. GA≥34weeks', the cortisol concentration on severe illness infants was significantly higher than mild ill infants within 72 hours (t=-2.263, P=0.029). GA< 34 weeks', the cortisol concentration on severe illness infants was significantly higher on the day 14 (t=-2.913, P=0.006).(2) The cortisol concentration was significantly decreased on the day 7 and day 14 than that within 72 hours in the GA≥34weeks' (F = 4.679, p = 0.012); (3) The cortisol concentration on death infants was significant higher than that on survivors on the day 14.(4) When the cortisol concentration was above the 75 th , the incidence of mechanical ventilation therapy, glucose metabolism disorder, gastrointestinal hemorrhage, severe periventricular -intraventricular hemorrhage and brain leukomacia, chronic lung disease, and mortality rate were increased strikingly. Conclusions:The preterm infant already has the ability to response stimuli by regulating cortisol secretion. The cortisol concentration is correlated with the severity of the disease, complications and prognosis.