Document Type



Paediatrics and Child Health; Pathology and Microbiology; Pathology and Laboratory Medicine


Background: We present our experience with optimization and diagnostic use of quantitative real-time polymerase chain reaction (PCR) targeting the lytA gene of Streptococcus pneumoniae for the detection of S. pneumoniae in whole blood of children ≥5 CFU/10 μl or 1 copy of DNA/2 μl of blood.
Methods: This assay was applied on 1912 whole blood specimens collected from children pneumonia, of which 35 specimens were lytA positive. The bacterial loads were determined through categorization of load into five different categories, i.e., very high load, high load, moderate load, low load, and very low load.
Results: Of the 35 lytA-positive samples, 9 (25.71%), 4 (11.42%), 1 (2.85%), 13 (37.14%), and 8 (22.85%) were categorized as very high load, high load, moderate load, low load, and very low load, respectively. Extracted samples were also subjected to serotyping by the Centers for Disease Control and Prevention PCR scheme. Positive samples with very high load and high load category were serotyped successfully in all instances. A high proportion of samples with low and very low load (61.53% and 75%, respectively) remained untypeable by the currently proposed schemes.
Conclusions: LytA PCR assay in whole blood provides rapid and sensitive results for the diagnosis of invasive S. pneumoniae disease in a resource-limited setting, while also being amenable to quantitation and serotyping.

Publication (Name of Journal)

Biomedical and Biotechnology Research Journal (BBRJ)

Creative Commons License

Creative Commons Attribution-Noncommercial-Share Alike 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.