10/06/2024
Satellitism test
The satellitism test is a microbiological assay used to identify bacteria, particularly Hemophilus species, by exploiting their specific nutritional requirements. Hemophilus influenzae requires two growth factors, X(hemin)and V (nicotinamide adenine dinucleotide, NAD), which are not typically present in standard media. To perform the test, a blood agar plate is streaked with Staphylococcus aureus, which releases the V factor. The suspected Haemophilus species is then streaked perpendicular to the Staphylococcus streak, and the plate is incubated. After 18-24 hours of incubation at 35-37°C in a CO2-enriched atmosphere, growth of Haemophilus near the Staphylococcus streak indicates a positive satellitism result, confirming the presence of Haemophilus species due to their ability to utilize the V factor provided by the Staphylococcus. This simple and cost-effective test is particularly useful for identifying Hemophilus influenzae in clinical samples
