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Evaluation of clinical and immunological effects of inactivated influenza vaccine in children with asthma.

Although annual influenza vaccinations are recommended by many authorities, some doctors may be reluctant to vaccinate asthmatic children because of the risk of inducing bronchial reactivity and exacerbating the asthma. In this study, the effect of split influenza vaccine on clinical symptoms, airway responsiveness and its influence on T lymphocytes was evaluated. Twenty-one asthmatic children with stable asthma were recruited and divided into two groups. Eleven patients who received the influenza vaccine formed the vaccination group and 10 patients who received a placebo formed the placebo group. Forced expiratory volume in 1 s (FEV1), airway response (PC20 methacholine, PC20=provocation concentration causing a 20% fall in FEV1) and the T lymphocyte subset ratio (Th1/Th2) were recorded on day 1 pre-vaccination and day 14 post-vaccination. Patients were also asked to record their peak expiratory flow (PEF) every morning and evening and to complete daily symptom scores over the period of 2 weeks. There were no significant changes in PC20, FEV1, PEF variability, symptom scores and the Th1/Th2 ratio between the vaccination and placebo groups between day 1 pre-vaccination and day 14 post-vaccination. Similar results of PEF variability and asthma symptom score were obtained when the analysis was restricted to the day 1 pre-vaccination and day 3 post-vaccination. Immunization with split influenza vaccine does not exacerbate asthma in children either with a clinical or immunological effect. These results suggest that children with stable asthma can safely be immunized with a split influenza vaccine.

Adolescent↗

Independent association of von Willebrand factor with surrogate markers of atherosclerosis in middle-aged asymptomatic subjects.

Von Willebrand factor (VWF) is considered a reliable marker of endothelial damage. Plasma levels of VWF were measured in 857 middle-aged subjects (80.4% men) free of clinically overt atherosclerotic disease, in relation to cardiovascular risk factors, carotid intima-media thickness (IMT) and microalbuminuria, two established surrogate markers of atherosclerosis. There was linear trend for the increase of VWF, carotid IMT (p < 0.001) and microalbuminuria (p = 0.018). The association between VEF and both markers remained statistically significant after adjusting for cardiovascular risk factors and inflammatory markers (p < 0.01). In conclusion, VWF was independently associated with both structural and functional surrogates of atherosclerosis in asymptomatic subjects, thus representing a systemic biomarker of subclinical atherosclerosis.

Adult↗

Increased but highly dispersed levels of plasma glycocalicin in patients with disseminated intravascular coagulation.

Thrombocytopenia is one of the most common laboratory manifestations of disseminated intravascular coagulation (DIC). To investigate whether thrombocytopenia in DIC is indeed due to platelet consumption, we measured the plasma levels of glycocalicin, a proteolytic fragment of the platelet membrane glycoprotein (GP) Ib alpha, a component of the GPIb/IX complex, in patients with solid tumors either with DIC(n=18) or without DIC (n=18). Patients with DIC had significantly elevated levels of glycocalicin(2.53 +/- 1.59 mg/1;n=18,p<0.05) compared to those without DIC (1.50 +/- 0.41 mg/1;n=18), indicating enhanced platelet consumption, or destruction, in patients with DIC. However, glycocalicin concentrations had a wide range (0.18-5.74 mg/1), and 3 DIC patients had levels lower than the normal lower limit. These findings suggest that, in patients with DIC, thrombocytopenia is not always due to increased platelet consumption, but it may be due to decreased production of platelets. Determination of plasma glycocalicin concentrations is an easy way to identify thrombocytopenia, due to bone marrow insufficiency in these patients.

Adult↗

Five parameters of gingival crevicular fluid from eight surfaces in periodontal health and disease.

Volume and amounts of myeloperoxidase (MPO), lactoferrin (LF), aryl sulfatase (AS) and lactate dehydrogenase (LDH) were measured in gingival crevicular fluid (GCF) collected from the mesial and distal proximal surfaces of the premolars and first and second molars of 3 subject groups. Group assignment was based on subject mean gingival index (GI) and probing depth (PD) of sampled sites as follows: healthy, GI less than or equal to 0.5, PD less than or equal to 3.0; disease 1, GI greater than or equal to 1.0, PD greater than or equal to 3.0 mm; disease 2, PD greater than or equal to 4.0 mm. Attachment loss (ATL) of most sites in the 3 groups was: healthy, 0-1 mm; disease 1, 1-2 mm; and disease 2, 4-9 mm. GCF volume differed among surfaces and teeth in each of the 3 groups. The greater amount of GCF collected from posterior locations was not related to the GI and PD. Differences with sampling location in amounts of GCF constituents were restricted to MPO and LF. Most of these differences (greater amounts at posterior sites) were associated with more severe disease. Variability in amount and composition of GCF collected from different sites, therefore, should be considered in experiments which include quantitation of GCF parameters. The ratio of MPO in disease group 2 to disease group 1 was greater than similar ratios for GCF volume and LF, AS and LDH. The quantity of MPO was the only measure which differed between the 2 disease groups at all surfaces. MPO thus appears to have the greatest potential, among the measured parameters, to serve as a marker for advanced periodontal disease.

Adult↗

Glycolipids of Mycobacterium tuberculosis strain H37Rv are potential serological markers for diagnosis of active tuberculosis.

A simple and cost-effective diagnostic tool (TB Screen Test) for the screening of patients with pulmonary and extrapulmonary tuberculosis and for differentiation of those individuals from individuals without tuberculosis, other common infections, and healthy controls has been developed. The serological responses of purified mycobacterial glycolipid antigens were examined by a liposome agglutination assay. The assay was able to detect very low antiglycolipid antibody concentrations in the infected individuals. The sera from the tuberculosis patient group had significantly higher concentrations of antiglycolipid antibody than the sera from uninfected control subjects, with 94% sensitivity and 98.3% specificity. Glycolipids of Mycobacterium tuberculosis H37Rv antigens were isolated, purified, and characterized. After interchelation with liposome particles, these purified antigens specifically bound to the antiglycolipid antibodies present in the sera of patients with tuberculosis, resulting in the formation of a blue agglutination. This protocol clearly differentiates healthy controls and M. bovis BCG-vaccinated subjects from those with active tuberculosis. The resultant diagnostic tool, the TB Screen Test, is more economical and rapid (4 min) than other currently available products and can be used for the mass screening of a heavily afflicted population.

Agglutination Tests↗

Monoclonal antibody recognizing a species-specific protein from Streptococcus pneumoniae.

Monoclonal antibodies (MAbs) against a nonencapsulated strain (R36A) of Streptococcus pneumoniae were produced to aid in a search for antigens common to this species. By Western immunoblot analysis, a species-specific 37-kilodalton (kDa) protein was found in lysates of 24 different encapsulated strains of S. pneumoniae. Monoclonal antibodies against the 37-kDa antigen did not react with 55 heterologous strains representing 19 genera and 36 species of bacteria that can also cause acute lower respiratory tract disease. Immunogold staining suggests that the antigen is synthesized inside the pneumococcal cell. However, MAbs to the 37-kDa antigen bound whole cells in the enzyme-linked immunosorbent assay and the indirect immunofluorescence assay. Antibody-binding epitopes of the antigen are probably exposed on the outer surface of the pneumococcus cell wall. The effectiveness of the 37-kDa antigen as a useful diagnostic marker is under study.

Antibodies, Bacterial↗

Diagnostic characteristics of a gelatin based Waaler-Rose assay (Serodia-RA) for the detection of rheumatoid factor.

OBJECTIVE: To evaluate the diagnostic usefulness of a gelatin based Waaler Rose assay (Serodia-RA) for the detection of rheumatoid factor (RF) in rheumatoid arthritis (RA). METHODS: RF was measured by Serodia-RA and rate nephelometry in 90 patients with RA according to the revised ACR criteria and 102 patients with rheumatological diseases other than RA. Sensitivity, specificity, accuracy, likelihood ratios, and area under the curve using receiver operating characteristics (ROC) analysis were determined for both tests. Agreement between assays was assessed on 1657 consecutive samples. RESULTS: At equal specificity, Serodia-RA tended to be more sensitive than rate nephelometry (0.66 v 0.58; p = 0.04). ROC plots showed an area under the curve of 0.843 for Serodia-RA and 0.784 for nephelometry, providing further evidence that Serodia-RA was slightly better at differentiating between RA and non-RA arthropathy. Good agreement was found between both assays. CONCLUSION: Serodia-RA is slightly more accurate than rate nephelometry for the detection of RF in RA, and a combination of both assays only marginally improves the diagnostic usefulness of RF detection. Use of two tests for detection of RF is not recommended. One test for detection of RF together with a more specific test, such as antibodies to cyclic citrullinated peptide, is suggested.

Adult↗

Serum amylase and acute pancreatitis.

A short cut review was carried out to establish whether a normal serum amylase value rules out the diagnosis of acute pancreatitis. Altogether 191 papers were found using the reported search, of which four presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these best papers are tabulated. A clinical bottom line is stated.

Acute Disease↗

Underestimation of acute pancreatitis: patients with only a small increase in amylase/lipase levels can also have or develop severe acute pancreatitis.

BACKGROUND: In most treatment studies on acute pancreatitis, pancreatologists base their diagnosis on amylase/lipase levels more than three times above the upper limit of normal (>3n) and thus exclude patients with smaller enzyme level increases. The recommendations derived from the results of treatment studies do not take into account such patients. Non-pancreatologists frequently believe that only patients with high enzyme levels have a serious prognosis. AIMS: To question the assumption that high enzyme levels indicate severe, and conversely low enzyme levels indicate mild, acute pancreatitis. PATIENTS/METHODS: This retrospective study includes 284 consecutive patients with a first attack of acute pancreatitis. The cause was biliary in 114 (40%) patients, alcoholism in 83 (29%), other in 21 (7%), and unknown in 66 (23%). Patients were divided into two groups according to their serum enzyme levels (amylase: </=3n, n = 88; >3n, n = 196; lipase: </=3n, n = 51; >3n, n = 233). Renal impairment, indication for dialysis and artificial ventilation, development of pseudocysts, necessity for surgery, and mortality were taken as parameters of severity. RESULTS: The incidence of severity was the same for both the </=3n and >3n groups. CONCLUSIONS: The severity of acute pancreatitis is independent of the elevation in serum amylase/lipase level (</=3n or >3n) on admission. Patients with only a slight increase can also have or develop severe acute pancreatitis. Patients with </=3n elevated enzyme levels on admission represent a substantial group that treatment studies have frequently overlooked. This is especially true for patients with alcohol induced acute pancreatitis whose amylase levels are lower than in other aetiological groups.

Acute Disease↗

Measurement of urea and ammonium concentrations in gastric juice.

AIM: To study the effect of known interference in the measurement of urea and ammonium concentrations in samples of gastric juice. METHODS: The effect of pH and ammonium concentration on the o-pthalaldehyde method, the diacetylmonoxime method, a Berthelot linked method and an enzymatic urease method for the measurement of urea in gastric juice was therefore conducted. An enzymatic method of the measurement of ammonium in gastric juice was also assessed. RESULTS: The o-pthalaldehyde and the enzymatic urease methods were unaffected by a low gastric juice pH, ammonium concentrations of 10 mmol/l, and had interassay coefficients of variation of 3.9-5.6% and 2.8-10.6%, respectively, over a urea concentration of 2.5 mmol/l-20 mmol/l. The Berthelot linked method resulted in low gastric juice urea concentrations. The enzymatic method of ammonium measurement also proved suitable when the effect of low gastric juice pH was controlled. CONCLUSION: Interference by low pH did not explain the differences in reports of gastric juice urea or ammonium concentrations.

Ammonia↗