Detection of pneumococcal antibodies in children with acute pneumonia and pleurisy by an immunoenzyme method

The samples of sera and pleural fluid from sick children have been analyzed by means of EIA techniques. To detect the time course of antibody production, the antigenic preparations of pneumococci (monovalent capsular polysaccharides, polyvalent polysaccharide vaccine and complex pneumococcal antigen) have been used. Antibody response observed in the forms of pneumococcal infection, studied in this investigation, has proved to be highly variable. It is expedient to determine antibodies to polysaccharide antigens not earlier than on days 10-12 from the beginning of the disease. But, besides the positive dynamics of antibodies, their unchanged level is sometimes observed in the patients at the beginning of the disease. As a rule, there is a coincidence between the dynamics of antibody formation in response to polysaccharide antigens and to complex pneumococcal antigen.     

Measles antibodies in exocrine secretions

The results of the analysis of saliva samples taken from 157 persons aged 1-48 years for the presence of antimeasles antibodies in the neutralization test, the hemagglutination inhibition test and the passive hemagglutination test are presented. The data obtained in this study suggest that antimeasles antibodies can be detected in saliva for many years after the formation of immunity, but quickly disintegrate after a saliva sample is taken.     

Microbiocenosis of the large intestine in acute complicated pneumonia in children

Fifty-six children of early age with pneumonia developed on the background of frequent respiratory infections were placed under observation. In 91.1% of these cases microecological disturbances in the intestine were detected, 46.6% of the patients having third-degree dysbacteriolysis. In such cases it is more correct to regard the "intestinal" syndrome as the clinical manifestation of disturbances in the biocenosis of the intestine, the state of its microflora. Intestinal dysbacteriosis aggravates the course of acute aggravated pneumonia in children and requires the inclusion of special therapy aimed at normalizing intestinal microflora.     

Streptococcus pneumoniae serotypes in children with acute pneumonia and pleurisy

The study of pneumococci of different serotypes, isolated from patients with acute pneumonia and pleuritis and from healthy children was carried out. Among the pneumococcal serotypes causing pneumonia and pleuritis in children serotypes 1, 6, 19, 14 and 3 were most widely spread and constituted 62.3% of all isolated pneumococci. In young children cases of acute pneumonia and pleuritis were more often induced by serotypes 6 and 14 and in older children, by serotypes 1 and 3. In patients with uncomplicated pneumonia and pleuritis differences in the detected serotypes of pneumococci were observed, and the disease course differed in severity. Serotypes 14, 3 and 3 induced destructive processes in the lungs more often than other serotypes. Monitoring of the sensitivity of pneumococci to antibiotics showed that most of the strains retained high sensitivity to penicillin and ampicillin. In most cases the detected resistant pneumococcal strains belonged to serogroup 19.     

Oxidative stress and enzymic-non-enzymic antioxidant responses in children with acute pneumonia

In this article, oxidative stress and enzymic-non-enzymic antioxidants status were investigated in children with acute pneumonia. Our study included 28 children with acute pneumonia and 29 control subjects. The age ranged from 2 to 11 years (4.57+/-2.13 years) and 2 to 12 years (4.89+/-2.22 years) in the study and control groups, respectively. Whole blood malondialdehyde (MDA) and reduced glutathione (GSH), serum beta-carotene, retinol, vitamin C, vitamin E, catalase (CAT), ceruloplasmin (CLP), total bilirubin, erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels were studied in all subjects. There was a statistically significant difference between the groups for all parameters except for serum CAT. Whole blood MDA, serum CLP and total bilirubin levels were higher in the study group than those of the control group. However, SOD, GPx, beta-carotene, retinol, vitamin C, vitamin E and GSH levels were lower in the study group compared with the control group. All antioxidant vitamin activities were decreased in children with acute pneumonia. Our study demonstrated that oxidative stress was increased whereas enzymic and non-enzymic antioxidant activities were significantly decreased in children with acute pneumonia.     

Lung ultrasound for the diagnosis of pneumonia in children with acute bronchiolitis

Background

Guidelines currently do not recommend the routine use of chest x-ray (CXR) in bronchiolitis. However, CXR is still performed in a high percentage of cases, mainly to diagnose or rule out pneumonia. The inappropriate use of CXR results in children exposure to ionizing radiations and increased medical costs. Lung Ultrasound (LUS) has become an emerging diagnostic tool for diagnosing pneumonia in the last decades. The purpose of this study was to assess the diagnostic accuracy and reliability of LUS for the detection of pneumonia in hospitalized children with bronchiolitis and to evaluate the agreement between LUS and CXR in diagnosing pneumonia in these patients.

Methods

We enrolled children admitted to our hospital in 2016–2017 with a diagnosis of bronchiolitis and undergone CXR because of clinical suspicion of concomitant pneumonia. LUS was performed in each child by a pediatrician blinded to the patient’s clinical, laboratory and CXR findings. An exploratory analysis was done in the first 30 patients to evaluate the inter-observer agreement between a pediatrician and a radiologist who independently performed LUS. The diagnosis of pneumonia was established by an expert clinician based on the recommendations of the British Thoracic Society guidelines.

Results

Eighty seven children with bronchiolitis were investigated. A final diagnosis of concomitant pneumonia was made in 25 patients. Sensitivity and specificity of LUS for the diagnosis of pneumonia were 100% and 83.9% respectively, with an area under-the-curve of 0.92, while CXR showed a sensitivity of 96% and specificity of 87.1%. When only consolidation >?1?cm was considered consistent with pneumonia, the specificity of LUS increased to 98.4% and the sensitivity decreased to 80.0%, with an area under-the-curve of 0.89. Cohen’s kappa between pediatrician and radiologist sonologists in the first 30 patients showed an almost perfect agreement in diagnosing pneumonia by LUS (K 0.93).

Conclusions

This study shows the good accuracy of LUS in diagnosing pneumonia in children with clinical bronchiolitis. When including only consolidation size >?1?cm, specificity of LUS was higher than CXR, avoiding the need to perform CXR in these patients. Added benefit of LUS included high inter-observer agreement.

Trial registration

Identifier: NCT03280732. Registered 12 September 2017 (retrospectively registered).

     

冬季肺炎和哮喘急性加重患儿呼吸道微生物多样性

目的 研究冬季肺炎和哮喘患儿呼吸道微生物的多样性。方法 选择2017年11月至2018年1月在我院急诊科治疗的确诊为肺炎和哮喘急性加重的患儿159例,其中肺炎患儿102例,哮喘急性加重患儿57例。选择同时期在本院就诊的无呼吸道疾病患儿88例,设为对照组。检测患儿呼吸道微生物分布情况。结果 肺炎和哮喘患儿呼吸道微生物多样性增加。肺炎患儿菌群丰度前3位的菌属分别是链球菌属、不动杆菌属、克雷伯菌属。哮喘患儿菌群丰度前3位的分别是嗜血杆菌属、莫拉氏菌属、葡萄球菌属。呼吸道病毒检测结果显示,肺炎患儿检出率前3位的病毒分别是肺炎支原体、呼吸道合胞病毒和副流感病毒3型。哮喘患儿病毒检出率前3位的是柯萨奇病毒、呼吸道合胞病毒和肺炎支原体。肺炎患儿肺炎支原体检出率明显高于哮喘患儿,柯萨奇病毒检出率明显低于哮喘患儿。结论 冬季肺炎和哮喘患儿的临床表现和体征较为相似,但是病原微生物检出情况有所不同。病原微生物检出的差异性有助于正确诊断和鉴别儿童肺炎和哮喘。     

Nonclassical mucosal antibodies predominate in genital secretions of HIV-1 infected chimpanzees

To identify mucosal immunity in HIV-infected chimpanzees, IgG, IgA, and IgM from plasma, saliva, rectal swabs, vaginal washes, semen, and urethral washes were tested from four male and three female HIV-1_IIIB infected chimpanzees. The level of HIV infections in the seven chimpanzees were classified as high, intermediate and low depending on the number of HIV-1 infected cells per 10⁷ peripheral blood mononuclear cells (PBMC). One male chimpanzee had a relatively high viral load, two males and two females had moderate viral loads and one male and one female had low levels of infection. All seven animals had plasma antibody. The principal finding was that nonclassical mucosal antibodies of the IgG isotype were the predominant antibody in the saliva, rectal swabs, vaginal washes, semen, and urethral washes of infected animals. All plasma and mucosal samples were negative for IgM antibodies. The results show that HIV-1 specific IgG responses and not sIgA predominate at mucosal surfaces of HIV-1_IIIB infected chimpanzees. A trend was observed in which high viral loads correlated with high plasma IgG, IgA and sIgA titers. An overall correlation between relatively high virus loads and high amounts of mucosal IgG was also found.     

Autoantibodies against bactericidal/permeability-increasing protein (BPI) in children with acute pneumonia

Antineutrophil cytoplasmic antibodies directed against bactericidal/permeability-increasing protein (BPI), an inhibitor of a lipopolysaccharide of gram-negative bacteria, are a common feature of chronic neutrophilic inflammatory processes such as cystic fibrosis. We investigated whether serum and salivary anti-BPI autoantibodies also appear in the course of acute pneumonia in 24 otherwise healthy children. Nine (38%) and four (17%) patients had detectable serum anti-BPI immunoglobulin G (IgG) (≥4 IU mL⁻¹) and IgA (ratio≥1.2), respectively, on the day of hospital admission (day 0). There was no increase in the rate of occurrence or the concentration of these antibodies in the convalescent sera obtained on day 30. The presence of anti-BPI IgG on admission did not correlate with inflammatory markers (peripheral white blood cell count, C-reactive protein) or temperature on admission. Also, salivary anti-BPI IgA, determined on days 0, 3–5 and 30, did not appear during the course of acute pneumonia. In summary, a substantial proportion of previously healthy children have pre-existing anti-BPI IgG autoantibodies. Acute neutrophilic infection, i.e. pneumonia, however, neither triggered the appearance of new antibodies nor boosted the concentrations of pre-existing ones. Thus, in typical acute pneumonia in children, autoantibodies directed against BPI may not have clinical significance.     

136例急性呼吸道感染患儿病原菌特点及鼻咽分泌物中呼吸道合胞病毒和人偏肺病毒基因分析

目的 分析136例急性呼吸道感染患儿的病原菌特点,并对患儿鼻咽分泌物中呼吸道合胞病毒(RSV)、人偏肺病毒(hMPV)进行检测,为后续研究提供参考。 方法 选择2017年1月至2019年4月我院收治的136例急性呼吸道感染患儿为研究对象,分析患儿呼吸道感染病原菌分布、耐药性,并对不同性别、年龄和感染部位患儿鼻咽分泌物中hMPV和RSV基因进行检测。 结果 136例急性呼吸道感染患儿共检出病原菌164株,其中革兰阴性菌占70.73%(116/164),革兰阳性菌占25.00%(41/164),真菌占4.27%(7/164);以铜绿假单胞菌(26.22%)、肺炎克雷伯菌(17.07%)、大肠埃希菌(15.24%)、金黄色葡萄球菌(12.20%)为主。药敏试验显示,铜绿假单胞菌、肺炎克雷伯菌、大肠埃希菌均对哌拉西林/他唑巴坦、头孢哌哃/舒巴坦、亚胺培南、左氧氟沙星、阿米卡星的耐药性较低(耐药率0.05)。1~2岁患儿hMPV检出率最高,0~5岁患儿RSV检出率较高。喘息性支气管炎、毛细支气管炎患儿hMPV检出率均较高,支气管肺炎、毛细支气管炎患儿RSV检出率均较高。 结论 急性呼吸道感染患儿病原菌以革兰阴性菌为主,应结合病原菌的药敏试验结果为患儿选择更有针对性的药物进行治疗。此外,应重视患儿RSV、hMPV感染情况,采取科学有效的方式对急性呼吸道感染进行预防和治疗。     

TT virus in the nasal secretions of children with acute respiratory diseases: relations to viremia and disease severity

The natural history and pathogenic potential of the recently identified TT virus (TTV) are currently a matter of intensive investigation. In an attempt to shed some light on these issues, nasal and blood specimens of 1- to 24-month-old children hospitalized with a clinical diagnosis of acute respiratory disease (ARD) were examined for the presence, load, and genetic characteristics of TTV. The results have indicated that at least in young children, the respiratory tract not only represents a route by which abundant TTV can be shed into the environment but also may be a site of primary infection and continual replication. Although we found no compelling evidence that TTV was the direct cause of ARD in some of the children studied, the average loads of TTV were considerably higher in patients with bronchopneumonia (BP) than in those with milder ARD, raising interesting questions about the pathophysiological significance of TTV at this site. Furthermore, group 4 TTV was detected almost exclusively in children with BP.     

肺炎支原体和沙眼衣原体致儿童急性下呼吸道感染的研究

本文旨在研究儿童社区获得性急性下呼吸道感染(ALRTI)中肺炎支原体(MP)和沙眼衣原体(CT)的感染特征。采用实时荧光定量聚合酶链反应(PCR)检测2006年10月～2008年2月因ALRTI收入复旦大学附属儿科医院的患儿呼吸道标本中MP和CT的DNA,并分析2种病原体感染患儿的临床特征与实验室检查结果。在1312份深部鼻咽分泌物标本中,MP和CT检出率分别为7.85%(103/1312)和2.97%(39/1312)。MP在5岁以上患儿中的检出率为33.33%(30/90),而CT在3个月以内患儿中的检出率为6.28%(31/494)。MP感染后易出现40℃以上高热,较少发生发绀与重症呼吸道感染;白细胞计数常无明显升高,但C反应蛋白升高较多见。CT感染后40℃以上高热和重症呼吸道感染少见,C反应蛋白升高也较少见。结果提示,在5岁以上儿童的社区获得性ALRTI中,MP是重要的病原体;而在3个月以内儿童中,CT为常见病原体之一。     

Detection of noncapsular antigens in pneumococcus

Complex antigenic preparations obtained from noncapsular pneumococcal strains were used for the immunization of rabbits and guinea pigs. The injection of the preparations in complete Freund's adjuvant for 5 weeks led to the appearance of antibodies in their sera. The antibodies were detected by the double immunodiffusion test. The preparations obtained from different strains by extraction (with Triton X-100 or sodium deoxycholate) or by disintegration contain common pneumococcal antigens.     

Use of the indirect hemagglutination reaction for detecting antibodies to Pseudomonas pyocyanea in acute suppurative destructive pneumonia]

No less than 4-fold increase in the antibody titres to Pseudomonas aeruginosa during the infectious process served as laboratory confirmation of its participation in the infectious process. In 49 of 91 patients hemagglutining titre exceeded the diagnostic one (1:640). In 9 patients (chiefly in infants) hemagglutinin titre remained low, but there was a rise of antibody level to Pseudomonas aeruginosa during the disease. High hemagglutinin titres were noted in 12 patients on admission to the clinic, with reduction of the antibody titres at the late periods of the disease. Antibody titres remained unchanged during the disease in 15 patients. In 3 cases the indirect hemagglutination test was assesed as negative. In the rest of the patients hemagglutinin titres varied within the range of the diagnostic titre. Thus, the indirect hemagglutination test with erythrocytic diagnostic agent permitting to determine antibodies to Pseudomonas aeruginosa could be used at the clinic in combination with bacteriological and other investigations for establishing etiology of the destructive process.     

5-Fluoropyrimidine-resistant mutants of pneumococcus

Three classes of 5-fluorpyrimidine-resistant mutants of Diplococcus pneumoniae have been characterized. The mutant strain upp is resistant to high concentrations of the fluoropyrimidine bases fluorouracil (FU) and fluorocytosine (FC); strain upp has a defective uridine monophosphate pyrophosphorylase. The mutant strain udk is resistant to inhibition by fluorouridine (FUR) and exhibits defective uridine kinase activity. The mutant strain fun is resistant to inhibition by the nucleosides fluorodeoxyuridine, fluorodeoxycytidine, and FUR, but shows normal activity for all pyrimidine pathway enzymes tested. This strain may be defective in the activity of a transport system that governs the cellular uptake of pyrimidine ribo- and deoxyribonucleosides. Biochemical studies on wild-type and fluoropyrimidine-resistant pneumococci are discussed with respect to the transport and early metabolism of preformed pyrimidine precursors by this organism.