Abrupt decline in kidney function defined by creatinine rise or oliguria. Frequently iatrogenic; preventable in many cases.

Rapid alveolar fluid accumulation causing severe respiratory distress. Most often cardiogenic from left ventricular failure, hypertensive crisis, ACS, or arrhythmia.

Acute, diffuse, inflammatory lung injury with bilateral infiltrates and hypoxaemia not fully explained by cardiac failure. Berlin definition stratifies severity.

Chronic inflammatory airway disease with variable, reversible airflow obstruction and bronchial hyperresponsiveness.

Acute infection of lung parenchyma acquired outside hospital. Stratify severity to guide treatment setting and antibiotic choice.

Medical emergency: hyperglycaemia (or known diabetes) plus metabolic acidosis and ketosis. Driven by absolute or relative insulin deficiency; typical in T1DM but can occur in T2DM (especially with SGLT2i).

Persistent BP ≥140/90 mmHg on ≥2 occasions. Major modifiable risk factor for stroke, IHD, heart failure, and CKD.

Life-threatening organ dysfunction caused by a dysregulated host response to infection. Time-critical: every hour of delayed antibiotic worsens outcome.

Subset of sepsis with circulatory and cellular/metabolic dysfunction: persisting hypotension requiring vasopressors plus lactate >2 mmol/L despite adequate fluid resuscitation.

Chronic hyperglycaemia from insulin resistance with relative insulin deficiency. Major driver of CV, renal, ophthalmic, and neurological complications.

Acute, predominantly viral infection of nose, throat, sinuses, or larynx. Self-limiting in most adults; antibiotics rarely indicated.

Bacterial infection of the bladder (cystitis) or upper tract (pyelonephritis). Most common pathogen: E. coli.