补充维生素A预防小儿腹泻和呼吸道感染性疾病的效果评价

205名1～5岁儿童,按血清维生素A含量和膳食中维生素A摄入水平分为2组。用单盲法每季度给实验组儿童补充50 000IU的维生素A,随访观察1年实验组和对照组儿童每人每年平均腹泻发病次数分别为0.089±0.02和0.347±0.30次;呼吸道感染性疾病分别为0.346±0.06和0.951±0.11次;每次病程天数分别为2.67±0.07与5.54±0.11和0.94±0.20与2.47±0.26天,均有统计学上的差异(P<0.05)。实验组儿童血清维生素A(1.22±0.06μmol/L)含量明显高于对照组(0.87±0.05μmol/L),也有非常显著性的差异(P<0.01)。结果说明该观察点儿童维生素A营养水平很低,补充维生素A后,可减少腹泻和呼吸道感染性疾病的发病率。     

三种维生素A干预方法对小儿抗感染免疫的作用

目的通过3种形式维生素A干预试验,观察小儿血清维生素A水平的变化及感染性疾病发生的情况。方法149名观察对象被随机分为4组:孕后期干预组:孕7、8个月分别给予孕母10万IU的维生素A;哺乳期干预组:产后1周内给予母亲20万IU的维生素A;小儿干预组:出生后4、5个月分别给予小儿10万IU的维生素A;对照组:未给予母亲或小儿任何干预。所有对象均随访至出生后1年,观察呼吸道与消化道感染性疾病发病情况。结果孕妇膳食维生素A摄入不足(总平均<80%RDA),所生小儿中有46%3个月时血清维生素A浓度低于正常范围(<1.05μmol/L)。小儿干预组小儿血清维生素A水平明显增高,生后3个月～1岁增长1.0倍;孕后期干预组与哺乳期干预组小儿血清维生素A无显著变化。尽管维生素A干预对腹泻、总呼吸道感染无明显保护作用,但小儿干预组小儿出生后1年内下呼吸道感染的年人均发病率(2%)明显低于对照组。结论维生素A干预,尤其是对小儿直接干预的方法可以直接改善小儿血清维生素A水平,并能降低其下呼吸道感染的发病率。     

辅食补充对贫困农村婴幼儿呼吸道感染和腹泻的影响

目的探讨强化辅助食品对婴幼儿呼吸道感染和腹泻两周内患病的影响。方法从甘肃省5个贫困县选取4~12个月的婴幼儿分成两组,所有儿童均在保持其家庭习惯的辅助食品添加的前提下,每天再补充1包不同配方的营养补充物,其中配方1组补充了蛋白质和微量营养素。每隔6个月对全部儿童补充一次大剂量的维生素A,两组儿童观察到满24个月为止。补充期间,每3个月进行一次体格测量,记录此期间儿童患呼吸系统疾病和腹泻的情况。结果补充12个月随访调查时,儿童近两周呼吸系统疾病和腹泻患病率下降明显,与基线调查比较,呼吸系统疾病和腹泻患病率的差异有显著性(P<0.001),同一次调查两配方组儿童疾病患病率之间差异无显著性;配方1组婴幼儿每次患呼吸系统疾病的病程逐渐下降。呼吸系统疾病和腹泻总的医疗费是明显下降的。结论补充营养素强化的辅食和大剂量维生素A,可以降低儿童腹泻和呼吸道感染的发病率,减少医疗费用。     

儿童反复呼吸道感染与血清维生素A、D、E水平的相关性研究

目的 探讨儿童反复呼吸道感染与患儿血清维生素A、D、E水平的相关性研究,为临床治疗提供科学依据。方法 选取2015年在长春市儿童医院参加儿童保健,近3个月反复呼吸道感染病史患儿66例为病例组;选取前来参加儿童保健的健康儿童66例为对照组。用高效液相色谱法检测维生素A、D、E的水平。结果 不同年龄组儿童患反复呼吸道感染疾病的差异有统计学意义(χ²=13.516,P=0.001),病例组儿童血清维生素A水平和缺乏率明显低于对照组(t=3.536,P=0.001;χ²=16.901,P=0.000),病例组儿童血清25(OH)D、维生素E水平和缺乏率与对照组比较差异无统计学意义(P>0.05)。结论 反复呼吸道感染可能与维生素A缺乏有关,建议加强营养教育和宣传,指导儿童家长进行科学喂养,定期监测维生素A、D、E水平并适量补充维生素。     

维生素A水平与重症下呼吸道感染患儿临床关系的研究

目的探究重症下呼吸道感染患儿维生素A水平对其临床转归和免疫功能的影响,为维生素A临床用于治疗儿童重症下呼吸道感染提供依据。方法从临床诊断为重症下呼吸道感染的患儿中筛选出维生素A缺乏的患儿,随机均分为研究组(n=60)和对照组(n=60),研究组给予常规治疗并辅以维生素A治疗,对照组给予常规治疗。治疗10天后观察患儿临床转归情况,并抽取静脉血复查维生素A水平、体液免疫、细胞免疫功能。结果入院时研究组和对照组患儿维生素A水平无明显差异(P0.05);经过十天的治疗后,研究组患儿血清维生素A水平高于对照组,差异有统计学意义(P0.05);研究组患儿的治疗有效率高于对照组,差异有统计学意义(P0.05);研究组患儿总T淋巴细胞、辅助性T细胞和细胞毒性T细胞相对计数均高于对照组,差异有统计学意义(P0.05);研究组患儿血清IgA、IgM和IgG水平均高于对照组,差异有统计学意义(P0.05)。结论维生素A干预治疗可通过提高重症下呼吸道感染患儿的免疫功能,从而有效改善患儿临床转归情况。     

每周小剂量补充维生素A对印度学前儿童腹泻、呼吸道感染及生长发育无明显作用

印度南方15419名半岁至5岁的儿童参加了为期1年的维生素A补充实验,以观察补充维生素A对儿童腹泻、呼吸道感染及生长发育的影响。参加实验者整群随机分为实验组和对照组。实验组儿童每周服8.7μmol(2500 μg)维生素A和46 μmol(20mg)的维生素E,对照组儿童给予46μmol维生素E作为空白对照。实验前后对儿童进行眼科检查和体格测量。实验期间由社区志愿人员每周对儿童发放一次药物,并通过询问母亲记录上周儿童的发病情况。     

儿童维生素A缺乏对感染性疾病的影响

目的:了解儿童血清维生素A缺乏(vitamin A deficiency,VAD)与感染性疾病的关系。方法:采取整群分层抽样抽取福建省9个地市3178名5岁以下儿童,检测维生素A,对其疾病史进行询问。结果:近3个月患急性呼吸道感染(ARI)、腹泻的儿童维生素A缺乏患病率为明显高于正常儿童;有腹泻的儿童维生素A缺乏患病率为无腹泻的2.37倍;等级剂量分析显示,发现腹泻次数越多,儿童维生素A缺乏患病率越高;有呼吸道感染的儿童维生素A缺乏患病率明显高于无呼吸道感染儿童,存在明显差异。结论:亚临床VAD是引起儿童发生急性感染性疾病的重要原因之一。婴儿早期预防应从服用鱼肝油开始,多食胡萝卜、肝脏等维生素A含量高的食物才是预防维生素A缺乏的根本方法,也是最有效、最迅速、经济的手段;同时口服维生素A对感染性疾病是一项有效而廉价的预防和辅助治疗的措施。     

渭南市60例儿童呼吸道感染与边缘型维生素A缺乏的相关性及危险因素分析

目的探讨渭南市60例儿童呼吸道感染与儿童边缘型维生素A缺乏之间的关系,分析儿童边缘型维生素A缺乏症的相关危险因素。方法选取2015年2月-2016年2月在渭南市第二医院进行治疗的反复呼吸道感染患儿60例作为病例组,同时期健康儿童60例作为对照组。比较两组儿童的血清维生素A水平和边缘型维生素A缺乏发生率。根据患儿的相关临床资料以及是否为边缘型维生素A缺乏症做Logistic回归分析。结果病例组儿童的维生素A水平显著低于对照组儿童(P<0.05),病例组儿童的边缘型维生素A缺乏发生率显著高于对照组(P<0.05),Logistic回归分析结果显示,家居城市、食欲好是儿童边缘型维生素A缺乏的保护因素(P=0.001、0.002),现患呼吸道感染是儿童边缘型维生素A缺乏的危险因素(P=0.004)。结论儿童呼吸道感染与维生素A缺乏具有相关性,而家居城市、儿童食欲好以及现患呼吸道感染与儿童边缘型维生素A缺乏有密切关联。     

补充外源性维生素A、维生素E对反复呼吸道感染儿童的影响

目的探讨补充外源性维生素A、维生素E对反复呼吸道感染儿童的影响。方法选取2012年7月-2013年8月邢台医学高等专科学校第二附属医院收治的非急性发作期反复呼吸道感染儿童100例,随机分为治疗组和对照组,每组各50例。两组在抗感染治疗的基础上,治疗组儿童予以维生素A和维生素E治疗1个疗程,对照组予以安慰剂服用1个疗程,随访1~3年。观察治疗前后两组儿童血清中维生素A、维生素E、IgA及IgG的含量变化及治疗效果。结果与对照组比较,治疗前两组患儿维生素A、维生素E、IgA及IgG水平差异均无统计学意义(P0.05)。治疗后,治疗组血清IgA水平高于对照组(1.33±0.26 mg/L vs.1.06±0.17 mg/L,P=0.000),血清IgG水平高于对照组(11.52±1.42 mg/L vs.10.24±1.78 mg/L,P=0.000),血清维生素A水平高于对照组(1.71±0.10μmol/L vs.1.46±0.13μmol/L,P=0.000),血清维生素E水平高于对照组(17.92±5.1μmol/L vs.15.83±5.30)μmol/L,P=0.047)。治疗组治疗显效人数较对照组明显增多(P0.05)。结论补充外源性维生素A、维生素E可降低反复呼吸道感染儿童的发病次数。     

对4个农村贫困县5岁以下儿童定期普服维生素A预防呼吸道感染和腹泻效果的前瞻性队列研究

目的:探讨定期普服维生素A对儿童感染性疾病患病率的影响。方法:分层抽样选取云南省4个县3669名5岁以下儿童,调查其两周患病情况,测量身高(身长)和体重,采用SPSS13.0软件进行统计分析。结果:①患病率及相对危险度(RR):支气管炎患儿服维生素A后患病率1.1%,RR=1.5,χ2=5.5,其他各疾病患病率服维生素A组明显低于对照组(服药前),RR均大于1,差异均有统计学意义。②归因危险度百分比(AR%):服维生素A后比服维生素A前各患病率降低19.2%～81.4%;人群归因危险度百分比(PAR%)为11.1%～69.2%。③平行对照:呼吸道、消化道感染及营养不良等患病率只有急性呼吸道感染和急性腹泻的相对危险度,对照组高于试验组;服维生素A双剂量优于单剂量。结论:普服维生素A对呼吸道和肠道感染有保护效应,双剂量效果更佳。     

Mild vitamin A deficiency and risk of respiratory tract diseases and diarrhea in preschool and school children in northeastern Thailand

A cross-sectional study, a follow-up study, and an intervention trial were carried out to investigate the association between mild vitamin A deficiency and the occurrence of diarrhea and respiratory diseases. Cross-sectional analysis was performed among 1,772 children, aged 1-8 years, in the Sakon Nakhon province of northeastern Thailand. Children with a history of diarrhea or respiratory disease had lower levels of serum retinol and retinol-binding protein. Adjusted for age, sex, nutritional status, and level of urbanization, logistic regression using data for 877 children showed a negative association between serum retinol and both diarrhea and respiratory diseases. A follow-up three months later (n = 146 children) showed that children with deficient serum retinol (less than 0.35 mumol/liter) had a fourfold greater risk of respiratory disease (p less than 0.01). No relation was found for diarrhea. An intervention trial (n = 166 children aged 1-5 years) showed that, during 2 months of follow-up after administration of oral vitamin A (200,000 IU), the control group (aged 3-5 years) had a higher incidence of respiratory disease (2.9 times) as well as diarrhea (3.1 times). Between 2 and 4 months, a significantly (p less than 0.025) higher incidence of respiratory diseases (2.5 times) could be observed in children aged 1-2 years. This study supports earlier reports on a greater risk of respiratory diseases and of diarrhea in mild vitamin A deficiency. Supplementation reduced the incidence of both diarrhea and respiratory disease for a period of at least 2 months.     

补充维生素A对儿童患病的影响

作者在前一个实验工作的基础上进一步扩大样本，对６７０名４岁以下儿童进行了为期二年的补充大剂量ＶＡ的实验观察，用双盲法对实验组儿童每６个月补充２０×１０４ＩＵＶＡ，由乡村医生每周访问儿童家长，记录儿童患病情况。结果表明对亚临床ＶＡ缺乏地区儿童补充大剂量ＶＡ能降低腹泻发生率，且其效果在疾病高发月份更明显，结果还表明血清ＶＡ低的儿童补充ＶＡ比血清ＶＡ水平较高的儿童效果明显；但对呼吸道感染性疾病虽然在疾病高发月份实验组发病比对照组低，但总的差异不明显。作者还对疾病资料收集方法进行了讨论。     

Evaluation of the effectiveness of the national vitamin A supplementation programme among school children in Sri Lanka

The Ministry of Health in Sri Lanka commenced a vitamin A supplementation programme of school children with a megadose of 105 micromol (100,000 IU) vitamin A in school years 1, 4 and 7 (approximately 5-, 9- and 12-year-olds, respectively) in 2001. We evaluated the vitamin A supplementation programme of school children in a rural area of Sri Lanka. A cross-sectional study was conducted among children supplemented with an oral megadose of vitamin A (105 micromol; n 452) and children not supplemented (controls; n 294) in Grades 1-5. Children were clinically examined and a sample of blood was taken for serum vitamin A concentration estimation by HPLC. Socio-demographic information was obtained from children or mothers. Supplemented children had a higher proportion of males and stunted children, were younger and lived under poorer conditions as compared to controls. There was no difference in the prevalences of eye signs and symptoms of vitamin A deficiency in the two groups. Supplemented children had higher serum vitamin A concentrations than controls (1.4 (SD 0.49) micromol/l v. 1.2 (SD 0.52) micromol/l). The serum vitamin A concentrations were 1.6 (SD 0.45), 1.4 (SD 0.50), 1.3 (SD 0.44) and 1.1 (SD 0.43) micromol/l in children supplemented within 1, 1-6, 7-12 and 13-18 months of supplementation, respectively. Vitamin A concentrations were significantly greater than controls if supplementation was carried out within 6 months after adjustment. The oral megadose of 105 micromol vitamin A maintained serum vitamin A concentrations for 6 months in school children.     

儿童维生素A缺乏与反复呼吸道感染相关性研究

目的 分析儿童血清维生素A与反复呼吸道感染之间的关系, 为维生素A预测及辅助治疗反复呼吸道感染提供依据。方法 选取2017年8月-2018年8月中国医科大学附属第四医院第二儿科收治的120例反复呼吸道感染患儿为观察组, 另取同期该院收治的120例呼吸道感染患儿为对照组, 检测两组患儿维生素A及免疫球蛋白(IgA、IgG、IgM)水平, 比较两组间维生素A水平的差异, 对维生素A 及免疫球蛋白进行相关分析, 并对观察组出院后随访1年, 记录出院后补充外源性维生素A的情况, 观察呼吸道感染的复发次数。结果 观察组患儿的维生素A水平低于对照组, 且观察组的亚临床型维生素A缺乏检出率高于对照组(t=2.632、χ²＝7.366, P＜0.05)。维生素A缺乏组患儿的IgG水平低于维生素A正常组 (F＝5.036, P＜0.05)。Pearson相关性分析显示, 维生素A与IgG呈正相关(r=0.172, P＜0.05)。治疗前, 补充维生素A组与未补充维生素A组患儿的呼吸道感染次数差异无统计学意义(P＞0.05);治疗后, 两组患儿的呼吸道感染次数均显著减少(t=9.291、2.036, P＜0.05), 且补充维生素A组少于未补充维生素A组(t=2.448, P＜0.05)。结论 反复呼吸道感染与维生素A缺乏有关, 补充维生素A有助于减少呼吸道感染的发生。     

补充维生素A对婴幼儿乙肝疫苗再免疫效果的促进作用

目的 观察补充维生素A(VA)对婴幼儿乙型病毒性肝炎(简称乙肝)疫苗再免疫效果的影响.方法 于2008年10月至2009年3月间,招募山东临沂某农村地区所有按国家计划免疫常规全程接种过乙肝疫苗的7～36月龄婴幼儿,检测其血清乙肝表面抗体(抗-HBs)浓度,对其中100名血清抗-HBs水平较低的婴幼儿进行随机(随机数字表法)、双盲、安慰剂对照的VA干预实验.干预组(50名)采用市售浓缩鱼肝油作为VA补充剂,补充期3个月,每15天补充1次,每次0.5 g浓缩鱼肝油[含25 000 IU VA和2500 IU维生素D2(VD2)],共补充6次;对照组(50名)给予等体积玉米油.在干预实验开始后第30和第60天,给婴幼儿进行乙肝疫苗再免疫接种,第90天采集婴幼儿血清样本.用高效液相色谱法(HPLC)测定干预实验前后婴幼儿血清视黄醇浓度.用电化学发光免疫分析法(ECLIA)测定血清抗-HBs水平.结果 共有74名婴幼儿完成干预实验,实验组和对照组各37名.干预后,干预组和对照组儿童的血清视黄醇浓度分别为(404.1±123.1)、(240.8±92.8)μg/L(t=6.441,P＜0.01);两组儿童的血清抗-HBs水平分别为(2737.2±2492.6)和(1199.7±2141.6)U/L(t=2.846,P＜0.01).干预组无乙肝疫苗弱、无应答情况(0/37),对照组乙肝疫苗弱、无应答率为10.81%(4/37)(x2=4.229,P=0.040).结论 补充VA可提高儿童乙肝疫苗再免疫后血清抗-HBs水平.

Abstract：

Objective The objective of this study was to observe the interventional effect of cod liver oil supplementation on re-vaccination to hepatitis B virus (HBV) among infants and young children. Methods All 7 -36 months old infants and young children, who had been vaccinated with obligatory HBV vaccines routinely by the national technical and administrative procedures for HBV vaccination on children of China, were convened among villages in Linyi, Shandong province, from October 2008 to March 2009. After detection of serum anti-HBV, one hundred children with lower serum anti-HBV were picked out for the randomized, double blinded, placebo controlled vitamin A supplementation study. The children in the intervention group (50 subjects) took 0. 5 g condensed cod liver oil ( containing 25 000 IU vitamin A and 2500 IU vitamin D2 ) every 15 days for six times. The children in the control group (50 subjects) were given corn oil with same volume. All children were re-vaccinated at the 30th and the 60th day of the experiment. The serum samples were collected from each child at the 90th day of the experiment. Retinol concentration in serum samples was analyzed with HPLC method before and after the intervention. The levels of serum anti-HBs were detected by the electro-chemi-luminescence immunoassay (ECLIA) .Results Total 74 children finished the supplemental experiment and blood collection,37 subjects in each group, respectively. After intervention, the serum retinol level in the experimental and control group were ( 404. 1 ± 123. 1 ) and ( 240. 8 ± 92. 8 ) μg/L ( t = 6. 441, P ＜ 0. 01 ), respectively. The serum anti-HBs levels in the experimental and control group were( 2737.2 ± 2492.6 )and( 1199. 7 ± 2141.6 )U/L ( t =2. 846, P ＜ 0. 01 ), respectively. The rate of weak or no-answer case in experimental and control groups was 0. 00% ( 0/37 ) and 10. 81% ( 4/37 ) ( x2 = 4. 229, P = 0. 040), respectively. Conclusion The results showed that vitamin A supplementation might enhance the re-vaccination reaction against HB vaccine in infants and young children.     

Vitamin A modifies the intestinal chemokine and cytokine responses to norovirus infection in Mexican children

Vitamin A supplementation is associated with divergent clinical norovirus (NoV) outcomes in Mexican children. Fecal cytokine concentrations following NoV genogroup infections among 127 Mexican children 5-15 mo old enrolled in a randomized, double-blind, placebo-controlled, vitamin A supplementation trial were determined to clarify the role the gut immune response plays in these associations. Stools collected from supplemented children [20,000 IU retinol (3.3 IU = 1 μg retinol) for children < 12 mo of age; 45,000 iu for children ≥ 12 mo] or children in the placebo group were screened for NoV genogroups I (GI) and II (GII). Monocyte chemoattractant protein-1 (MCP-1), TNFα, IL-5, IL-6, IL-8, IL-4, IFNγ, and IL-10 fecal concentrations were also determined. Differences in cytokine levels between the 2 groups following GI and GII infections were determined using ordered logistic regression models. MCP-1 and IL-8 levels were greater among GI- and GII-infected children, respectively, compared with uninfected children, whereas IL-5 levels were greater following both genogroup infections. MCP-1, IL-8, and IL-6 fecal levels were reduced among supplemented children with GII-associated diarrhea compared with the placebo group. Vitamin A-supplemented, GII-infected children had reduced MCP-1 and TNFα levels compared with GII-infected children in the placebo group (P-interaction = 0.02 and 0.03, respectively). Supplemented children with GI-associated diarrhea had higher TNFα and IL-4 levels compared with children in the placebo group with diarrhea (P-interaction = 0.02 and 0.02, respectively). The divergent effects of supplementation on NoV outcomes may result from the different effects vitamin A has on the genogroup-specific immune responses.     

Respiratory infections reduce the growth response to vitamin A supplementation in a randomized controlled trial

BACKGROUND: Studies on the effect of vitamin A supplementation on growth have yielded various results. It is possible that such growth is dependent on the burden of infectious diseases in the population. METHODS: We analysed data from a randomized, double-masked, placebo-controled trial to examine the role of respiratory infections and diarrhoea in modifying the growth response to vitamin A supplementation. A single high dose of vitamin A or placebo was given every 4 months to 1405 children aged 6-48 months, and 4430 child treatment cycles were used in this analysis. RESULTS: Vitamin A supplementation modestly improved linear but not ponderal growth of children who experienced little respiratory infection and especially of those who had vitamin A intake below the normative requirement (<400 RE/day). Children who received vitamin A and were free of respiratory infection grew 0.22 cm/4 months (95% CI: 0.08, 0.37) more in height than the placebo group, but those with > or =21.5% of days of respiratory infection did not show a significant growth response to vitamin A supplementation. Children who experienced no respiratory infection and had vitamin A intake <400 RE/day benefited most, gaining 0.31 cm/4 months (95% CI: 0.10, 0.52) more in height compared to the placebo group. Diarrhoea was associated with poorer growth, but did not significantly modify the effect of vitamin A supplementation on growth. CONCLUSIONS: Vitamin A supplementation improves the linear growth of children who have a low intake of vitamin A but this impact is muted with increasing levels of respiratory infections.     

Effect of vitamin A supplementation on diarrhoea and acute respiratory tract infection in children

To determine the effect of a massive single oral dose of Vitamin A (200,000 IU) supplementation on diarrhoea and acute respiratory infection (ARI), a double blind placebo controlled trial involving 174 children under six years of age (excluding infants) was carried out in a Calcutta slum community. Ninety-one children received vitamin A supplementation (experimental group) and 83 children received a placebo (control group). All the children were followed up for six months by active fortnightly surveillance for occurrence of diarrhoea or ARI and their duration. There was no statistically significant difference in the incidence of diarrhoeal episodes or ARI. However, there was a significant difference (p<0.05) in the average duration of diarrhoea per episode (2.1 vs. 3 days) between the experimental and control groups. Possible beneficial effects of a single oral dose of vitamin A supplementation on the incidence of diarrhoea and ARI could not be demonstrated in the present study.     

Effects of moderate doses of vitamin A as an adjunct to the treatment of pneumonia in underweight and normal-weight children: a randomized, double-blind, placebo-controlled trial

BACKGROUND: Randomized controlled trials have shown inconsistent responses of childhood pneumonia to the use of vitamin A as an adjunct to the standard treatment of pneumonia. OBJECTIVE: We evaluated the effect of a moderate dose of vitamin A as an adjunct to standard antimicrobial treatment on the duration of respiratory signs in children with pneumonia. DESIGN: Children, aged 2-59 mo, with pneumonia and weight-for-age <50th percentile who had been admitted to the Baca Ortíz Children's Hospital in Quito, Ecuador, were randomly assigned to receive 50,000 IU (aged 2-12 mo) or 100,000 IU (aged >12-59 mo) vitamin A or a placebo. RESULTS: Of the 287 children enrolled, 145 received vitamin A and 142 received placebo. No overall differences were observed between the 2 groups in the duration of signs of pneumonia. Multiple linear regression showed a significant interaction between basal serum retinol concentration and vitamin A group for the time (in h) to remission of respiratory signs (beta = -3.57, SE = 1.09, P = 0.001). Duration of clinical signs was less in children with basal serum retinol concentrations >200 microg/L who received vitamin A supplements than in children with similar concentrations who received placebo (69.9 +/- 49.9 h compared with 131.3 +/- 143.9 h; P = 0.049). CONCLUSIONS: Overall, we found no effect of a moderate dose of vitamin A supplementation on the duration of uncomplicated pneumonia in underweight or normal-weight children aged <5 y. However, a beneficial effect was seen in children with high basal serum retinol concentrations.