Specimens used for the laboratory diagnosis of Streptococcus pneumoniae/Haemophilus influenzae may be
- Specimens from respiratory tract: Sputum, lung aspirate, pleural fluid
- Body fluids e.g., Blood/ cerebrospinal fluid
- Exudates from joint, other sites, middle ear
Collection of specimens for laboratory diagnosis of Streptococcus pneumoniae and Haemophilus influenzae
Collect > 1.0 ml expectorated sputum in a sterile screw-capped container.
- Lung aspirate/ pleural fluid
Collect > 1.0 ml by percutaneous needle aspiration in a sterile screw-capped tube.
Clean the venipuncture site with 70% alcohol and iodine, allow it to evaporate and collect blood aseptically in a culture broth with an anticoagulant. In case of adults, collect 5-10 ml blood in culture bottle, for children < 12 year old, collect 1.5-2.0 ml blood. Mix the blood and broth by rotating gently to avoid clotting.
- Cerebrospinal fluid (CSF):
Clean the skin over L3-L4 inter-space with 70% alcohol and iodine. Collect > 1.0 ml CSF in a sterile screw-capped tube. Keep the CSF in an incubator at 35-37 degree centigrade, if it is not processed immediately.
- Exudates from joints/middle ear
Collect > 1.0 ml by aspiration in a sterile screw-capped tube or add directly in a culture broth used for blood culture.
Note: DO NOT REFRIGERATE THE SAMPLE
Transportation of clinical specimens for laboratory diagnosis of Streptococcus pneumoniae and Haemophilus influenzae
Streptococcus pneumoniae and H. influenzae are fastidious bacteria. Care must be taken during transport of specimen. Specimens must be transported promptly to the laboratory preferably within 1-2 hours.
Blood can only be transported after collecting in a culture broth containing appropriate anticoagulant. The inoculated medium can be held at room temperature (20°C– 25 °C) for 4 – 6 hours before incubation at 37 °C. The samples during transportation should be protected from extremes of temperature (less than 18 °C, more than 30 °C) and direct sunlight.
SOP for processing clinical specimens for laboratory diagnosis of Streptococcus pneumoniae and Haemophilus influenzae will be continued in the following posts: