# Infection screening, prophylaxis and immunoglobulin replacement around CAR T-cell therapy

Source: https://onco.cc/protocols/car-t-infection-prevention/  
OnCo record `car-t-infection-prevention` (Protocol). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Infections are the commonest serious problem in the months after CAR T-cell therapy. You are first tested for hepatitis B, HIV and other viruses. Afterwards most centres give tablets against shingles, cold sores and a type of pneumonia for at least six months, check antibody levels, and may give antibody infusions if they are low and infections recur. Any fever needs a call to the team at once.

## Summary

ASTCT 2024: screen before lymphodepletion with HIV antibody, hepatitis B (HBsAg, anti-HBc, anti-HBs), hepatitis C antibody, CMV IgG and HTLV-1, syphilis by risk, and baseline HBV DNA if HBsAg is positive; delay for symptomatic lower respiratory infection. Prophylaxis: acyclovir or valacyclovir from lymphodepletion until at least 6 months after infusion (shorter in children); trimethoprim-sulfamethoxazole for Pneumocystis from count recovery (by day 30) until at least 6 months, after a study in which 2 of 40 patients developed severe PJP when prophylaxis stopped at 3 months; entecavir for at-risk hepatitis B until at least 12 months; fluconazole through neutropenia where antifungal prophylaxis is universal, and mould-active azoles for higher risk; fluoroquinolone prophylaxis is controversial and may be replaced by monitoring with prompt antibiotics. Any fever after infusion needs an infection work-up and broad-spectrum antibiotics, since CRS treatment can mask infection.

Immunoglobulin: measure IgG before and in the first 3 months; consider IVIG for IgG of 400 mg/dL or less with severe or recurrent bacterial infections, and when IgG is under 200 mg/dL (ASTCT). SITC 2020 measures B cells and immunoglobulins monthly and considers replacement for high-risk adults and for children with IgG under 400 mg/dL; EBMT/JACIE 2019 keeps IgG at 500 mg/dL or more in children with B-cell aplasia and recommends tenofovir, not entecavir, for a history of hepatitis B.

## Fields

- Kind: Protocol
- Last checked: 2026-11-11
- Also known as: CAR-T antimicrobial prophylaxis; CAR T infection prevention; IVIG after CAR T; hypogammaglobulinaemia after CAR T; PJP prophylaxis CAR T
- Tags: protocol; cell-therapy; car-t; infection

## Connected records

- protocols: [Cytokine release syndrome after CAR T-cell therapy: ASTCT grading, tocilizumab and steroids](https://onco.cc/protocols/crs-grading-and-management/), [ICANS after CAR T-cell therapy: ICE score, ASTCT grading, steroids and seizure management](https://onco.cc/protocols/icans-grading-and-management/), [IEC-HS after CAR T-cell therapy: recognition and stepwise treatment](https://onco.cc/protocols/iec-hs-management/), [Lymphodepleting chemotherapy before CAR T-cell infusion](https://onco.cc/protocols/car-t-lymphodepletion/), [Prolonged low blood counts after CAR T-cell therapy (ICAHT): grading, work-up and treatment](https://onco.cc/protocols/icaht-prolonged-cytopenia/), [Referral and eligibility assessment for CAR T-cell therapy](https://onco.cc/protocols/car-t-referral-and-eligibility/), [T-cell engaging bispecific antibodies: step-up dosing, monitoring and outpatient delivery](https://onco.cc/protocols/bispecific-step-up-dosing/)
- technologies: [CAR-T cell therapy](https://onco.cc/technologies/car-t/)
- drugs: [Axicabtagene ciloleucel](https://onco.cc/drugs/axicabtagene-ciloleucel/), [Brexucabtagene autoleucel](https://onco.cc/drugs/brexucabtagene-autoleucel/), [Ciltacabtagene autoleucel](https://onco.cc/drugs/ciltacabtagene-autoleucel/), [Human normal immunoglobulin (IVIg)](https://onco.cc/drugs/human-normal-immunoglobulin/), [Idecabtagene vicleucel](https://onco.cc/drugs/idecabtagene-vicleucel/), [Lisocabtagene maraleucel](https://onco.cc/drugs/lisocabtagene-maraleucel/), [Obecabtagene autoleucel](https://onco.cc/drugs/obecabtagene-autoleucel/), [Tisagenlecleucel](https://onco.cc/drugs/tisagenlecleucel/)
- terms: [Hepatitis B and C as cancer causes](https://onco.cc/terms/hbv-hcv/), [Immunoglobulin replacement after CAR-T, bispecifics and long anti-CD20 treatment](https://onco.cc/terms/lymphoma-tx-immunoglobulin-replacement/)

---
JSON: https://onco.cc/api/v1/entities/car-t-infection-prevention.json