MRSA Testing-
Q1. What type of testing do you have available for MRSA?
A1. There are two assays currently available from MDL for MRSA testing. Test 1118: Methicillin resistant Staphylococcus aureus (MRSA) by conventional PCR and Test 1119 Panton-Valentine Leukocidin (PVL) DNA by Real-Time PCR.
Q2. What is the difference between the two tests available for MRSA?
A2. Test 1118 will determine if MRSA or Methicillin Susceptible Staphylococcus aureus (MSSA) is present in a sample. If Test 1118 returns a positive result, then 1119 can differentiate hospital and community associated MRSA.
Test 1118 also has the ability to determine the type of a mobile genetic element or transposon within MRSA called the Staphylococcal Cassette Chromosome (SCC) which carries the genes that cause methicillin resistance such as mecA. There are 4 main types of SCCs named type I, type II, type III, and type IV. SCC type I, II, and III are typically found in Hospital Associated MRSA (HA-MRSA) strains, while Type IV in conjunction with a positive PVL gene, test 1119, are typically found in Community Associated MRSA (CA-MRSA) strains. The SCC types within HA-MRSA strains also typically have other antibiotic resistance genes associated with them that could limit the number of alternative antibiotics used to treat MRSA. The CA-MRSA is typically a more virulent MRSA strain that can cause more aggressive infections, however the SCC type IV does not typically contain other antibiotic resistance genes, therefore when detected early can be easily treated with a number of alternative antibiotics
Q3. What type of specimens do you accept for MRSA testing?
A3. We accept a swab of nasopharyngeal surfaces collected with a NasoSwab™ or swabs of skin surfaces, boils, vaginal and anal tracts using the OneSwab®.