General information about this test:
NADAL® Streptococcus Pneumoniae Test is a rapid chromatographic immunoassay for qualitative detection of Streptococcus pneumoniae in urine samples with no need of dilution. NADAL® Streptococcus Pneumoniae Test is aimed to aid diagnosis ofpneumonia, otitis media and meningitis and is intended for professional use only.
Reagents and material supplied:
- 10 NADAL® Streptococcus Pneumoniae test cassettes (incl. disposable pipettes)
- 1 package insert
Test time: 10 min
Performance characteristics:
The NADAL® Streptococcus Pneumoniae Test shows no cross-reactivity with the following microorganisms: Strep A, B, C, D, E, F, G & H, Staphylococcus Aureus, Bacillus subtitilis. Positive result for cross-reactivity with Streptococcus Pneumoniae capsular types (8) was observed.
The diagnostic specificity and sensitivity data for NADAL® Streptococcus Pneumoniae Test were confirmed by comparison with another rapid immunoassay – BinaxNOW® Streptococcus pneumonia.
Diagnostic sensitivity: 79%
Diagnostic specificity: 84%
Overall agreement: 81%
Analytical sensitivity of NADAL® Streptococcus Pneumoniae Test was determined by testing diluted S. pneumonia cultures and further comparison of the results with the those obtained by means of BinaxNOW® Streptococcus pneumonia. Both tests show the same sensitivity.
Intra-assay reproducibility: 100%
Test principles:
The NADAL® Streptococcus Pneumoniae Test is a qualitative lateral flow immunoassay for the detection of S. pneumoniae antigens in urine (without sample dilution). The NADAL® Streptococcus Pneumoniae Test owes its sensitivity to two monoclonal antibodies targeted at different epitopes. First, the anti-S. pneumoniae antibodies eventually present in the sample (in the case of positive result) react with antibodies bound to coloured particles pre-dried on the internal test strip, further the samples moves along the membrane by capillary action and specific antibodies present on test line react with the mixture conjugate and generate a rose-pink-colored line in the test (T) region of the cassette. A rose-pink line should always appear in the control line region (C)and serves as a procedural control, indicating that the proper volume of specimen has been added and membrane wicking has occurred.
Clinical significance:
Streptococcus pneumoniae (S. pneumoniae) is a gram-positive lancet-shaped anaerobic bacterium first isolated from the saliva of a patient with rabies by Pasteur in 1881. The chemical structure and antigenicity of the pneumococcal capsular polysaccharide, its association with virulence and its role in human disease were thoroughly examined in the beginning of the XXth century. The bacteria are spread by direct person-to-person contact via respiratory droplets. The 10 most common serotypes are estimated to cause about 62% of invasive disease worldwide. S. pneumoniae infects upper respiratory tract tissues causing severe pneumonia and mild to acute earache/ otitis. Bacterial pneumonia accounts for 12-16% of invasive pneumococcal disease among children aged 2 years and younger.
Pneumococci cause 13% to 19% of all cases of bacterial meningitis in the United States. One-fourth of patients with pneumococcal meningitis also have pneumonia. Clinical symptoms of this meningitis type are generally similar to those of other forms of purulent bacterial meningitis and include headache, lethargy, vomiting, irritability, fever, nuchal rigidity, cranial signs, seizures and coma. The mortality rate of meningitis caused by pneumococci is about 30% but can reach 80% elderly patients. S. pneumoniae is the main cause of bacterial meningitis among children younger than 5 years of age in the United States.
Antibiotic treatment is efficient even against penicillin-resistant strains. Several vaccines are available with variable efficiency depending on patient age or whether patients are developing some chronic illness or immunodeficiency.