Synopsis
Recognise life-threatening checkpoint-inhibitor, CAR-T and bispecific-antibody toxicity, treat infection and other mimics in parallel and start severity- and organ-specific immune rescue without waiting for routine oncology review.
- Immune toxicity can affect any organ and may begin during treatment or weeks to months after the last checkpoint dose; ask specifically about the exact immune product and date.
- Withhold further immune therapy for clinically significant suspected toxicity and contact acute oncology or the cellular-therapy centre immediately.
- First-line assessment combines ABCDE, sepsis cultures and lactate, FBC, renal, liver, glucose, cortisol and thyroid tests with organ-specific ECG, troponin, CT, stool or neurological evaluation.
- Do not let an immune-toxicity label delay antibiotics, anticoagulation, drainage or other treatment for a plausible coexisting emergency.
- Severe checkpoint toxicity commonly requires intravenous methylprednisolone 1 to 2 mg/kg/day or the organ-specific protocol, followed by a slow taper after objective improvement.
- Give hydrocortisone 100 mg IV immediately for suspected adrenal crisis, then 200 mg over 24 hours or 50 mg every 6 hours with intravenous saline and endocrine review.
- For protocol-defined significant CAR-T CRS, tocilizumab 8 mg/kg IV up to 800 mg can be repeated at intervals of at least 8 hours to a maximum four total doses; treat sepsis concurrently.
- Tocilizumab does not adequately treat isolated ICANS; significant neurotoxicity uses structured scoring, corticosteroid and seizure or critical-care management through the treating centre.
Key red flags
New breathlessness, hypoxaemia or diffuse lung change during checkpoint therapy may be pneumonitis, infection or embolism and requires urgent imaging and oncology review.
Chest pain, troponin rise, conduction change, arrhythmia or heart failure can represent immune myocarditis with a high early mortality.
Hypotension, vomiting, hyponatraemia, hypoglycaemia or severe weakness can indicate immune adrenal insufficiency or hypophysitis and needs immediate hydrocortisone.
Fever with hypotension or hypoxia soon after CAR-T or a bispecific antibody is possible cytokine-release syndrome, but bacterial sepsis must be treated in parallel.
New handwriting change, word-finding difficulty, inattention, tremor, focal weakness, seizure or reduced consciousness after cellular therapy raises ICANS.
Increasing stool frequency, nocturnal diarrhoea, blood, pain or fever can progress to dehydration, toxic dilatation and perforation.
Troponin elevation, chest pain, heart block or arrhythmia with ptosis, diplopia or proximal weakness suggests myocarditis with myositis or myasthenia.
Vomiting, hypotension, hypoglycaemia, hyponatraemia, headache or visual change can indicate adrenal insufficiency or hypophysitis.
Inattention, dysgraphia, word-finding difficulty, tremor or altered behaviour can precede seizure and
Investigation priorities
Identify infection, shock and the organ systems requiring immediate support.
Management branches
A patient exposed to immune therapy develops a new inflammatory, endocrine, cardiac or neurological syndrome.
- Use ABCDE and monitoring, identify exact product and dates, hold further immune treatment and contact acute oncology or the cellular-therapy centre immediately.
- Obtain sepsis and organ-directed tests and start antimicrobials and other emergency treatment when indicated without waiting for a toxicity grade.
- Assign organ and severity grade and arrange the monitoring setting, recognising myocarditis, respiratory weakness, adrenal crisis, CRS and ICANS may need critical care early.