Indications for ambulatory antimicrobial therapy

The clinical diagnosis should be established before the patient is referred to an ambulatory antimicrobial therapy service; this may require additional investigations. If required, other components of infection management, such as surgical debridement, are usually performed before admission for ambulatory antimicrobial therapy.

Infections that are commonly treated with ambulatory antimicrobial therapy include skin and soft tissue infections, bone and joint infections and endocarditis. Patients with misdiagnosed cellulitis are commonly referred for ambulatory antimicrobial therapy. A range of other infections can also be managed with ambulatory antimicrobial therapy, as long as patient selection criteria are met (see Patient selection for ambulatory antimicrobial therapy). An increasing number of patients with multidrug-resistant infections (eg urinary tract infection) and nontuberculous mycobacterial infections are managed with ambulatory antimicrobial therapy – consultation with a specialist is required.

Some infections are not suitable for management via ambulatory antimicrobial therapy. These include infections that are severe, or can cause rapid deterioration and severe complications that are difficult to manage outside hospital (eg septic emboli from left-sided infective endocarditis). Ambulatory antimicrobial therapy can be considered for such infections in selected patients after a period of stabilisation in hospital.

Patients with moderate- or high-severity community-acquired pneumonia (CAP) or severe pyelonephritis are at risk of deterioration, and should generally be managed in hospital while receiving parenteral antimicrobials. When the patient is well enough to go home, a switch to oral therapy is usually appropriate. If there are no options for oral therapy (eg due to antimicrobial resistance or drug intolerance), ambulatory parenteral antimicrobial therapy may be suitable.

In certain circumstances it may be appropriate to treat patients with parenteral antibiotics in the community who do not meet the criteria (see Patient selection for ambulatory antimicrobial therapy); for example, a patient with moderate- to high-severity CAP in an aged-care facility, when management in hospital does not fit with the patient’s goals of care – see Parenteral therapy for CAP in residents of aged-care facilities.