目的 探讨新生儿坏死性小肠结肠炎(NEC)炎症损伤与肠道微生态-LPS-TLR4通路之间的关系。方法 本研究收集2019年3月1日—2021年1月31日在中山市人民医院新生儿监护室确诊为NEC新生儿11例为实验组,随机选取30 例同期在新生儿科病房住院喂养顺利,排除NEC及败血症诊断的新生儿为对照组。采集2组新生儿的粪便标本,进行Real-time PCR表达谱分析2组粪便肠道菌群;取2组外周静脉血检测外周血单核细胞Toll样受体4(TLR4)和血清PCT、CRP、IL-6、SAA等指标,对比2组肠道菌群、外周血单核细胞TLR4和炎症指标水平,通过统计学分析组间差异。结果 本研究结果提示实验组变形菌门占82%(9/11),厚壁菌门占9%(1/11),放线菌门占9%(1/11),对照组变形菌门占20%(6/30),厚壁菌门占73%(22/30),放线菌门占7%(2/30),2组患儿的粪便肠道菌群分布有差异(χ²=11.521,P<0.05);实验组患儿外周血单核细胞TLR4水平高于对照组,组间差异有统计学意义(P<0.001);实验组患儿血清PCT、CRP、IL-6和SAA等炎症指标高于对照组,组间差异有统计学意义(P<0.001)。结论 NEC患儿的肠道菌群以变形菌门为主,伴外周血单核细胞TLR4和外周血炎症指标升高。可见,肠道微生态-LPS-TLR4通路可能与新生儿坏死性小肠结肠炎炎症损伤相关,具体的机制仍需进一步深入研究。

Objective To investigate the relationship between intestinal flora-LPS-TLR4 pathway and the inflammatory injury of neonatal necrotizing enterocolitis (NEC). Methods Eleven neonates with NEC from March, 2019 to January, 2021 were enrolled as the experimental group, and 30 neonates without NEC and septicemia who were admitted in the department of neonatology in the same period were included as the control group. Faecal flora from the two groups were collected and analyzed by Real-time PCR. Toll-like receptor 4 (TLR4) and serum PCT, CRP, IL-6, SAA in peripheral blood were measured. The intestinal flora, the expression of TLR4 in peripheral blood leukocytes and inflammatory markers were compared between two groups. Results It showed that the ratio of Proteobacteria was 82% (9/11), Firmicutes was 9% (1/11), Actinobacteria was 9% (1/11) in the experimental group. In the control group, the ratio of Proteobacteria was 20% (6/30), Firmicutes was 73% (22/30), Actinobacteria was 7% (2/30). There was a significant difference in the distribution of faecal flora between the two groups (χ² = 11.521, P<0.05), and the level of TLR4 in peripheral blood of the experimental group was significantly higher than that of the control group (P＜0.001). The levels of serum PCT, CRP, IL-6 and SAA in the experimental group were significantly higher than those in the control group (P＜0.001). Conclusions The main intestinal flora of neonates with NEC is Proteobacteria, with elevated TLR4 expression and inflammatory markers in peripheral blood. Therefore, the intestinal flora-LPS-TLR4 pathway may be associated with inflammatory injury in neonatal necrotizing enterocolitis.The specific mechanism still needs further study.

目的 探讨原发性肉碱缺乏症的诊断与治疗方案,对2例原发性肉碱缺乏症患儿及其家系行SLC22A5基因检测,确定基因突变位点,为家系提供遗传疾病的咨询。方法 用串联质谱技术对1例疑似患儿进行游离肉碱及多种酰基肉碱检测,对游离肉碱降低的患儿行SLC22A5基因突变检测,确诊PCD,对其姐姐行上述检查。对2例确诊PCD患儿补充左旋肉碱治疗,随访11个月。并对其家系行SLC22A5基因检测。结果 2例确诊PCD患儿,1例为临床患儿,另1例为其姐姐,无明显临床表现。2例患儿均检测到基因突变。2例患儿血游离肉碱水平低于参考值,伴多种酰基肉碱显著降低,均给予补充左旋肉碱治疗,1例治疗2月后症状改善,另1例未曾未发病,血游离肉碱及其他酰基肉碱水平上升至正常。2例患儿SLC22A5 c.760C>T,(p.Arg254X)纯合,致病突变;患儿父母亲SLC22A5基因的c.760C位点检测,发现:均携带c.760C>T,(p.Arg254X)杂合突变。结论 应用串联质谱技术检测血游离肉碱、多种酰基肉碱水平及SLA22A5基因突变检测诊断了2例PCD,均补充左旋肉碱取得较好疗效。SLC22A5基因c.760C>T,(p.Arg254X)突变是本家系中患有PCD的致病突变,用错义突变和剪切改变的分析手段对SLC22A5基因的外显子编码区进行直接测序可为PCD家系提供遗传咨询。

Objective To explore the diagnosis and treatment of primary carnitine deficiency. To identify potential mutation of SLC22A5 gene in two children affected with primary carnitine deficiency and provide genetic counseling. Methods We measured the free camitine(Co)and acylcamitine levels in a suspected clinical inherited metabolic diseases by tandem mass spectrometry. The SLC22A5 gene mutations were tested to the children with low Co level and the diagnosis was made. Then, We measured the free camitine(Co)and acylcamitine levels and SLC22A5 gene mutations in her sister. The children with PCD were treated with carnitine and followed up for 11 months. The SLC22A5 gene was detected in their family. Results In two children affected with PCD, 1 case was clinical children, another case of their sister was no obvious clinical manifestations. Mutations were found in all of them.The average C0 level in patients was lower than the reference value,along with decreased level of different acylcamitines. Two cases were treated with earnitine. Their clinical symptoms reduced 2 months later. Another case had not been sick. The CO level and different acylcamitines level in the blood rose to normal. A homozygous mutation C. 760C>T (P. Arg254X)of the SLC22A5 gene was detected in the two cases.Heterozygous mutation C. 760C>T (P.Arg254X) was also found in other family members. Conclusion Two patients were diagnosed with PCD by the test levels of free carnitine and acylcarnitines in blood with tandem mass spectrometry,and gene mutation test. L-carnitine supplement had a good effect in treatment of the PCD patients.C.760C> T (P.Arg254X) mutations of the SLC22A5 gene is the deleterious mutations for PCD families, The analysis method of the wrong mutagenesis and shear changes which is used to directly sequence the exons codes of the SLC22A5 gene can provide genetic counseling for PCD families.