Parameter |
HA-MRSA |
CA-MRSA |
Typical patient |
Elderly, debilitated and/or critically or chronically ill |
Young healthy people, students, professional athletes and military personnel |
Infection site |
Often bacteraemia with no obvious source of infectionAlso surgical wounds, open ulcers,i.v.lines and catheter urinesMay cause ventilator-associated pneumonia |
Predilection for skin and soft tissue producing cellulitis and abscessesMay cause necrotising community-acquired pneumonia, septic shock or bone and joint infections |
Transmission |
Within healthcare settings; little spread among household contacts |
Community acquired; may spread in families and sports teams |
Clinical setting of diagnosis |
In an in-patient setting, but increasingly HA-MRSA infections in soft tissue and urine are occurring in primary care |
In an outpatient or community setting |
Medical history |
History of MRSA colonisation, infection or recent surgery; admission to a hospital or nursing home; antibiotic use; dialysis, permanent indwelling catheter |
No significant medical history or healthcare contact |
毒性感染strain |
Community spread is limited PVL genes usually absent |
Community spread occurs easily PVL genes often present, predisposing to necrotising soft tissue or lung infection |
Antibiotic susceptibility |
Often multiresistant with the result that the choice of agents is often very limited |
Generally susceptible to more antibiotics than HA-MRSA |