Cripps Allan W, Otczyk Diana C, Barker Jane, Lehmann Deborah, Alpers Michael P
School of Medicine, Griffith University, Gold Coast, Queensland, Australia.
P N G Med J. 2008 Sep-Dec;51(3-4):120-30.
Malnutrition is a significant risk factor for childhood infectious diseases in developing countries, including Papua New Guinea (PNG). Whilst the mechanisms are not fully understood there is little doubt that impairment of immune function is a major contributing factor in enhancing disease susceptibility in malnourished children. This susceptibility has been clearly shown for pneumonia in PNG. The aim of this study was to examine the effect of undernutrition on the humoral immune profile in children less than 60 months of age with pneumonia. The study was cross-sectional with measurements of nutritional status and parameters of the immune response being assessed simultaneously. The children were grouped according to age for the purpose of comparative analysis. The children were from the Goroka region of the Eastern Highlands Province of PNG and had been admitted to hospital with moderate-severe pneumonia. They were classified as undernourished (less than 80% weight for age) or nourished (greater than or equal to 80% weight for age). Serum albumin, IgG, IgA and IgM and salivary albumin and IgA were measured. Antibodies to nontypeable Haemophilus influenzae outer membrane protein and Escherichia coli O antigen were also determined in serum and saliva. Undernourished children aged less than 49 months had lower levels of serum albumin than nourished children throughout this age range. Lower values of salivary IgA were observed in infants (less than 13 months of age) than in older children, with a larger proportion of younger children having no detectable IgA. The age-related immunological profile was similar in undernourished and nourished children. At different age intervals the concentration of immunoglobulins in serum and saliva from undernourished children was generally found to be less than or the same as that from nourished children. In most cases undernourished children had lower levels of specific antibodies than nourished children but for some antibodies in some age groups the levels in the undernourished were higher. In conclusion, undernutrition was associated with hypoalbuminaemia and reduced humoral immune responses in children with pneumonia but its immunological effects varied with age in an unpredictable way.
在包括巴布亚新几内亚（PNG）在内的发展中国家，营养不良是儿童传染病的一个重要风险因素。虽然其机制尚未完全明了，但毫无疑问，免疫功能受损是营养不良儿童疾病易感性增强的一个主要促成因素。这种易感性在PNG的肺炎病例中已得到明确证实。本研究的目的是检验营养不良对60个月以下患肺炎儿童体液免疫状况的影响。该研究为横断面研究，同时评估营养状况和免疫反应参数。为进行比较分析，将儿童按年龄分组。这些儿童来自PNG东部高地省戈罗卡地区，因中度至重度肺炎入院。他们被分为营养不良（年龄别体重低于80%）或营养良好（年龄别体重高于或等于80%）。测量血清白蛋白、IgG、IgA和IgM以及唾液白蛋白和IgA。还测定了血清和唾液中针对不可分型流感嗜血杆菌外膜蛋白和大肠杆菌O抗原的抗体。在整个这个年龄范围内，49个月以下的营养不良儿童血清白蛋白水平低于营养良好的儿童。观察到婴儿（小于13个月）唾液IgA值低于年龄较大的儿童，且年龄较小的儿童中未检测到IgA的比例更高。营养不良和营养良好儿童的年龄相关免疫状况相似。在不同年龄区间，一般发现营养不良儿童血清和唾液中免疫球蛋白浓度低于或与营养良好儿童相同。在大多数情况下，营养不良儿童的特异性抗体水平低于营养良好儿童，但在某些年龄组中，某些抗体在营养不良儿童中的水平更高。总之，营养不良与肺炎儿童的低白蛋白血症和体液免疫反应降低有关，但其免疫效应随年龄变化，方式不可预测。
