Use of computed tomography abdomen and pelvis for investigation of febrile neutropenia in adult haematology patients

The diagnostic utility of computed tomography scans performed for febrile neutropenia in a single centre

BACKGROUND

Computed tomography (CT) imaging has become a first line investigation for most cases of febrile neutropenia (FN) which can be the only sign of infection in oncology patients undergoing active chemotherapy and bone marrow transplants. The utility of routine non-targeted imaging remains unclear.

OBJECTIVE

To assess and compare the diagnostic rate between targeted, non-targeted and pan-scan CT in identifying an acute source of infection in adult oncology patients with FN.

MATERIALS AND METHODS

A retrospective observational study was conducted between February 2019 and March 2023 on 417 consecutive CT examinations for the clinical indication of source identification in FN. Scans were noted for the anatomical regions that were imaged and reports were classified as positive, negative or equivocal for infection. Pre-existing pathology was also noted. Results were tabulated and statistical analyses for comparison between groups of scans was performed using chi-square test.

RESULTS

All targeted regional scans had statistically significant difference in positive rate compared to non-targeted scans of the respective region; chest (Χ²(1)=18.11, P<.001); sinus (Χ²(1)=15.36, P<.001); abdomen and pelvis (Χ²(1)=5.95, P=.01). Pneumonia (41.3 %) was much more likely to be the diagnosis compared to sinusitis (16.2 %) in concomitant CT chest to sinus examinations (Χ²(1)=45.3, P<.001). Pan-scans had a higher incidence of positive diagnosis compared to all-targeted scans (Χ²(1)=4.91, P=.03) but when compared to higher yield targeted scans (abdomen and chest), there was no statistical difference (Χ²(1)=2.43, P=.12). 20/54 patients had pan-scans despite having localising symptoms.

CONCLUSION

Imaging guided by presenting signs and symptoms can help to reduce unnecessary imaging and promote more judicious use of non-targeted and pan-scan CT in current practices.

New approaches to management of fever and neutropenia in high-risk patients

PURPOSE OF REVIEW

Patients receiving treatment for acute leukaemia and haematopoietic cell transplantation (HCT) have prolonged neutropenia and are at high risk of neutropenic fever, with bacterial and particularly invasive fungal infections as feared complications, possessing potentially serious consequences including intensive care admission and mortality. Concerns for these serious complications often lead to long durations of broad-spectrum antimicrobial therapy and escalation to even broader therapy if fever persists. Further, the default approach is to continue neutropenic fever therapy until count recovery, leaving many patients who have long defervesced on prolonged antibiotics.

RECENT FINDINGS

This article details recent progress in this field with particular emphasis on early discontinuation studies in resolved neutropenic fever and improved imaging techniques for the investigation of those with persistent neutropenic fever. Recent randomized controlled trials have shown that early cessation of empiric neutropenic fever therapy is well tolerated in acute leukaemia and autologous HCT patients who are clinically stable and afebrile for 72 h. Delineation of the best approach to cessation (timing and/or use of fluoroquinolone prophylaxis) and whether this approach is well tolerated in the higher risk allogeneic HCT setting is still required. Recent RCT data demonstrate utility of FDG-PET/CT to guide management and rationalize antimicrobial therapy in high-risk patient groups with persistent neutropenic fever.

SUMMARY

Acute leukaemic and autologous HCT patients with resolved neutropenic fever prior to count recovery can have empiric therapy safely discontinued or de-escalated. There is an emerging role of FDG-PET/CT to support decision-making about antibiotic and antifungal use in high-risk persistent/recurrent neutropenic fever patients.

Management of fever and neutropenia in the adult patient with acute myeloid leukemia

INTRODUCTION

Febrile neutropenia represents one of the most common treatment-associated complications in the management of acute myeloid leukemia (AML) and is considered an oncologic emergency. Rapid and detailed workup as well as the initiation of empiric broad-spectrum antibiotic therapy are critical to avoid sepsis and to reduce mortality. Although a definitive source of infection is frequently not identified, the severely immunosuppressed status of the AML patient undergoing cytotoxic therapy results in a high risk for a wide array of bacterial, fungal, and viral etiologies.

AREAS COVERED

The authors herein review the diagnostic and therapeutic approach to the neutropenic leukemia patient based on the current knowledge. Special consideration is given to the rapidly changing therapeutic landscape in AML, creating new challenges in the management of infectious complications.

EXPERT OPINION

Multidrug-resistant organisms pose a major challenge in the management of neutropenic fever patients with hematologic malignancies - including AML. Future directions to improve outcomes demand innovative treatment approaches as well as advances in biomarker research to facilitate diagnosis and disease monitoring. Recent achievements in AML-targeted therapy led to an increased incidence of differentiation syndrome, a potentially life-threatening side effect that frequently resembles clinical infection and requires prompt recognition and aggressive intervention.