Investigation of follow-up for lactase deficiency and physical growth in hospitalized newborns
YE Huan RAO Yan-xiao XU Chen YU Dong RUAN Huan
1.Department of Pediatrics, The Affiliated Hospital of Hangzhou Normal University, Zhejiang, Hangzhou 310015,China; 2.Medical College of Hangzhou Normal University, Zhejiang, Hangzhou 310018,China; 3.The Children's Hospital Zhejiang University School Of Medicine, Zhejiang, Hangzhou 310052, China)
Abstract: 【Abstract】 Objective To investigate the incidence of lactase deficiency and lactose intolerance in hospitalized newborns, and follow-up the physical growth of the patients with lactose intolerance. Methods From February 2017 to July 2018, 250 neonates in the Department of Pediatrics , The Affiliated Hospital of Hangzhou Normal University were included according to the criterion. Urine was extracted within 1-2 h after feeding for the urine galactose qualitative determination test, and the positive result of the diarrhea, vomiting and other clinical symptoms would be diagnosed as lactose intolerance. The incidence of lactase deficiency was compared between the premature newborns (72 cases) and term newborns (178 cases) according to gestational age. The cases were followed up to 12 months and their height and weight were measured. The Z-score values were calculated. According to the results of detection and follow-up, they were divided into lactose intolerance group (42 cases) and lactase non-deficiency group (60 cases). The growth was compared between the two groups. T test, χ2 test or Fisher exact probability method were used for statistical analysis. Results 181 cases were positive result from the urine galactose qualitative determination test in 250 newborns, the incidence of lactase deficiency was 72.4 %. The incidence of lactase deficiency in the preterm groups and term groups was 84.7% (61/72) and 67.4% (120/178) respectively with statistical significance (χ2=7.684, P<0.05). 46 cases of lactase deficiency with lactose intolerance, the incidence of lactose intolerance was 18.4 %.The follow-up results showed at 12 months of age, the △ WLZ、 △ WAZ of the lactase intolerance groups were lower than that of the lactase non-deficiency groups[(0.6±1.1) vs (1.9±1.2), (0.8±1.1) vs (1.5±0.9), all P<0.05], there
was no significant difference in △ LAZ between the two groups (P>0.05). The incidence of low weight in
the lactase intolerance groups was higher than that in the lactase non-deficiency groups (19.1% vs 5.0%,
P<0.05). The incidence of obesity in the lactase intolerance groups was lower than that in the lactase non-
deficiency groups (0% vs 10.0%, P<0.05). There was statistical significance (all P<0.05). Conclusions The incidence of lactase deficiency is high in neonatal period, the incidence of lactase deficiency in preterm infants is higher than that in term infants. Only a part of the infants with lactase deficiency have lactose intolerance and affect the growth rate of weight and nutritional status for the infants, but there is no affection for the growth rate of height.