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Severe Bacterial Infections

A bacterial infection is severe when it threatens organ function, spreads to normally sterile tissue or destabilises breathing or circulation. Suspected sepsis is an emergency.

Key takeaways

  • Confusion, rapid breathing, low blood pressure, mottled skin, very low urine output or rapid deterioration can indicate severe infection.
  • Infection site, cultures, organ function, immune status and local resistance guide initial treatment and later narrowing.
  • Urgent antibiotics may be lifesaving when bacterial sepsis is suspected, but the wrong agent can delay adequate coverage and cause harm.

Catalogue matches are not emergency treatment and do not identify the organism, dose, route or combination required.

How is severity recognised?

Severe illness can occur with fever, low temperature or no fever. Clinicians assess circulation, oxygen, mental state, urine output and likely source, then obtain tests without delaying time-critical treatment when sepsis is suspected.

How are antibiotics chosen?

Initial therapy reflects the source and resistance risk, then culture results support narrower treatment. Chloramphenicol has limited specialist uses and serious blood-toxicity risks; a catalogue listing is not a reason to use it. See antibiotics.

When to seek urgent care

Call emergency services for confusion, severe breathlessness, blue or mottled skin, collapse, a non-blanching rash, very low urine output or rapid deterioration with suspected infection.