E005 Immunoglobulins review prior to rituximab infusion: implications and how we can improve our service
Authors: Kalluri Ujjvala , Thanopoulou Vasiliki , Malley Tamir 
Published: April 2024

Abstract

Background/Aims
Rituximab (RTX), used in the treatment of autoimmune and lymphoproliferative diseases, depletes B-cells through anti-CD20. The resulting hypogammaglobulinemia increases susceptibility to recurrent or severe infections, however the absence of a protocolised approach to measuring serum immunoglobulin levels prior to, or between, RTX infusions in our infusion unit has led to cancelled treatments, and even delivery of treatments without a timely record of immunoglobulin levels. British Society for Rheumatology guidelines recommend checking immunoglobulin levels prior to treatment, then four to six months after infusions and before any future cycles of treatment. Our aim was to optimise monitoring standards of immunoglobulin levels in patients receiving RTX infusions, thereby minimising avoidable harm and unnecessary treatment cancellations.

Methods
Data was collected retrospectively using electronic patient records. The analysis included sixty patients with rheumatological conditions scheduled for RTX infusions during a three-month period.

Results
Treatment was appropriately withheld in six patients without up-to-date immunoglobulin levels, and in one patient with active infection. However, RTX was given in 28% (17 out of 60) of patients without up-to-date immunoglobulin levels; the mean duration of time between the current cycle of RTX treatment and most up-to-date prior immunoglobulin result being 179 days (median 109 days). Of note, this exceeded 200 days for 4 of these 17 patients (24%), and an absence of pre-RTX immunoglobulin levels was observed in a further 3 of these 17 patients (18%). Although no adverse events have occurred, this represents a compromise in patient safety. Whilst there is no definitive guidance on the reasonable maximum time limit between a RTX infusion and the most up-to-date immunoglobulin levels, a departmental consensus of one month was agreed upon through discussion and literature reviews. Robust measures have been taken, using a multi-disciplinary and multi-step approach, to achieve this:1. Patient list generated one week in advance for the clinical team to review pre-screening tests, including immunoglobulins. Any missing tests can be requested in advance of the infusion date.2. Pharmacy update of their checklist to include reviewing immunoglobulins results prior to dispensing Rituximab; escalating to the clinical team if missing or abnormal result.3. If the above measures have failed, a final safety net has been agreed by the multi-disciplinary team that bloods are taken and urgently processed in the laboratory, with RTX conditionally screened by pharmacy, to reduce treatment delay from appointment cancellation.

Conclusion
Next steps will be to develop this into a first cycle of quality improvement. This will involve measuring changes from comparing data points prior to and after implementation of the above changes. Furthermore, rates of post-RTX infections or complications of immunodeficiency will be measured before and after the interventions to determine the impact on patient safety and minimise avoidable harm and unnecessary treatment cancellations.

Disclosure
U. Kalluri: None. V. Thanopoulou: None. T. Malley: None.