T-cell based immunotherapy-associated cytokine release syndrome

What it is

From: Orphanet

A rare systemic condition affecting patients undergoing chimeric antigen receptor (CAR) T-cell therapy and characterized by a systemic inflammatory response due to massive activation of leukocytes with subsequent cytokine release. It can present with a variety of signs and symptoms ranging from mild, flu-like symptoms (such as fever, fatigue, headache, rash, arthralgia, and myalgia) to severe life-threatening manifestations including vascular leakage, disseminated intravascular coagulation, shock, and multiple organ failure. Respiratory manifestations are common and range from cough and tachypnea to acute respiratory distress syndrome (ARDS).

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Abnormal circulating interleukin concentration · Very frequent (99-80%)

The concentration of an interleukin (a class of cytokines) is outside the limits of normal.

Abnormality of serum cytokine level · Very frequent (99-80%)

Abnormality of the cytokine levels in the blood, i.e., an abnormality of any of the non-antibody proteins made by inflammatory leukocytes and some non-leukocytic cells that affect the behavior of other cells.

Fatigue · Very frequent (99-80%)

A subjective feeling of tiredness characterized by a lack of energy and motivation.

Fever · Very frequent (99-80%)

Body temperature elevated above the normal range.

Increased inflammatory response · Very frequent (99-80%)

A abnormal increase in the inflammatory response to injury or infection.

Hypotension · Frequent (79-30%)

Low Blood Pressure, vascular hypotension.

Increased circulating interleukin 6 concentration · Frequent (79-30%)

The concentration of interleukin-6 in the blood circulation is above the upper limit of normal.

Increased serum interferon-gamma level · Frequent (79-30%)

An elevation in the concentration of interferon gamma measured in the blood circulation.

Myalgia · Frequent (79-30%)

Pain in muscle.

Poor appetite · Frequent (79-30%)

A reduced desire to eat.

Tachycardia · Frequent (79-30%)

A rapid heartrate that exceeds the range of the normal resting heartrate for age.

Arrhythmia · Occasional (29-5%)

Any cardiac rhythm other than the normal sinus rhythm. Such a rhythm may be either of sinus or ectopic origin and either regular or irregular. An arrhythmia may be due to a disturbance in impulse formation or conduction or both.

Capillary leak · Occasional (29-5%)

An acute phenomenon characterized by hypotension and anasarca due to the loss of plasma volume into peripheral tissues, with evidence of decreased plasma volume (hemoconcentration) and protein loss from the intravascular space (hypoalbuminemia) during acute episodes.

Confusion · Occasional (29-5%)

Lack of clarity and coherence of thought, perception, understanding, or action.

Other findings in the same source

From: Orphanet

Additional reported features include Decreased urine output (Occasional (29-5%)); Diarrhea (Occasional (29-5%)); Elevated circulating creatinine concentration (Occasional (29-5%)); Elevated circulating hepatic transaminase concentration (Occasional (29-5%)); Heart block (Occasional (29-5%)); Hyperbilirubinemia (Occasional (29-5%)); Hypoxemia (Occasional (29-5%)); Nausea (Occasional (29-5%)); Pleural effusion (Occasional (29-5%)); Pulmonary edema (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Adult

Inheritance in the source

From: Orphanet

Not applicable

Frequency and the population described

From: Orphanet

Point prevalence: Unknown; Worldwide; Class only.

Which doctor should you see?

The suggested department for discussing T-cell based immunotherapy-associated cytokine release syndrome is Rheumatology, with a rheumatologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Are the findings inflammatory, structural or due to another mechanism?
• Is there evidence that other organs need assessment?
• How will function and any treatment-related risks be monitored?

Treatment discussions and follow-up

Where the source describes treatments, these are an overview of possible care, not a prescription for an individual. Ask which option applies to the confirmed diagnosis, what benefit is expected, what adverse effects to watch for and how progress will be assessed. Availability, approvals and local practice can differ from the country described in the source.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.