Febrile neutropenia and infection in oncology: Case

The problem representation

This is a five-year-old boy on day ten of induction chemotherapy for acute lymphoblastic leukaemia presenting with febrile neutropenia. The single temperature of 39.0 degrees Celsius meets the fever threshold of 38.5 degrees Celsius or higher on one reading, and his absolute neutrophil count of 0.08 times ten to the ninth per litre is profound and well under the 0.5 threshold (Lehrnbecher et al., J Clin Oncol 2017, PMID 28459614). The mucositis and the induction window make him high-risk. He is presumed bacteraemic from the moment the temperature is taken. [2]

The first-hour bundle

The immediate management is the first-hour empiric bundle. The clock starts at recognition. I would assess the airway, breathing and circulation, confirm the perfusion is adequate, and look briefly for a focus and for the high-risk features. I would draw blood cultures from every lumen of the central line and peripherally before the first antibiotic dose, send a urinalysis, and take a chest radiograph, none of which would delay the antibiotic. I would then start the empiric intravenous anti-pseudomonal beta-lactam, ceftazidime, piperacillin-tazobactam, cefepime, or meropenem, weight-dosed by the oncology protocol, within the first hour (Freifeld et al., Clin Infect Dis 2011, PMID 21258094). [1]

Because he has mucositis, which is a defined indication, I would add vancomycin to the beta-lactam. Vancomycin is added, never substituted, when there is suspected line infection, a serious soft-tissue or pulmonary focus, mucositis, haemodynamic instability, severe sepsis, or known colonisation with methicillin-resistant Staphylococcus aureus; routine empiric vancomycin is not recommended because it adds nephrotoxicity without a mortality benefit (Freifeld et al., Clin Infect Dis 2011, PMID 21258094). The cultures and the panel are processed in parallel, never in series before the dose. [1][2]

Risk stratification and disposition

By the International Pediatric Fever and Neutropenia Guideline, this child is high-risk on the grounds of the mucositis as a comorbidity and the induction window with an anticipated prolonged neutropenia (Lehrnbecher et al., J Clin Oncol 2017, PMID 28459614). The prospective SPOG 2003 FN study of Ammann and colleagues quantified the predictors of adverse events, including the depth of the neutropenia, the monocyte count, the inpatient status, and the comorbidity, and it is the basis for the contemporary risk model (Ammann et al., J Clin Oncol 2010, PMID 20231680). As a high-risk child, he is admitted to the oncology ward for inpatient intravenous monotherapy for the duration of the neutropenia, continuing at least until he is afebrile and the absolute neutrophil count is recovering above 0.5 and rising. A low-risk child, by contrast, would be the candidate for oral step-down and selected outpatient care, but he is not. [6][2]

The persistent-fever pathway

If his fever were to persist beyond 96 hours with ongoing severe neutropenia and negative cultures, the persistent-fever pathway applies. I would re-examine him, repeat the blood cultures, send a galactomannan and a beta-D-glucan, and obtain a high-resolution chest and, if indicated, sinus computed tomography to look for an invasive mould. I would then add an empiric antifungal agent, liposomal amphotericin B, caspofungin, or voriconazole, or follow a pre-emptive strategy in which the galactomannan, beta-D-glucan and imaging guide the start of a targeted antifungal, an approach supported by the randomised trial of Santolaya and colleagues in high-risk children (Santolaya et al., J Antimicrob Chemother 2018, PMID 30010931). [11][2]

The line and the supportive care

His central line exit site is clean on presentation. A simple exit-site infection may clear with antibiotics and local care, but a tunnel infection, a port-pocket abscess, or a catheter-related bloodstream infection that persists beyond 72 hours of appropriate antibiotics requires line removal, as do bacteraemias with Staphylococcus aureus, Pseudomonas aeruginosa, Candida, Bacillus, atypical mycobacteria, and vancomycin-resistant enterococci (Freifeld et al., Clin Infect Dis 2011, PMID 21258094). If a line-demanding organism is grown, the line comes out after the appropriate antibiotics are established and a plan for ongoing access is made. [1]

The supportive-care strategy runs in parallel. Maintain meticulous oral hygiene for the mucositis, care for the central line with a strict aseptic technique, avoid rectal examinations and rectal suppositories, avoid non-steroidal anti-inflammatory drugs that mask the fever and impair platelet function in a child who is thrombocytopenic, and continue the co-trimoxazole prophylaxis for Pneumocystis. The antimicrobial-duration principle is to narrow or stop when the cultures and the recovery allow, continuing only as long as the indication persists. The family is given a clear explanation of the diagnosis, the plan, and the safety-net to return immediately for any new fever, rigors, or clinical deterioration. [1][2]

The teaching points

Three lessons anchor the case. First, the door-to-antibiotic interval is the single most important process measure, and the systematic review of Koenig and colleagues found that a shorter time to antibiotics is associated with better outcomes (Koenig et al., Support Care Cancer 2020, PMID 31264188). Second, the blunted inflammatory response means that fever is often the only sign of bacteraemia, so well does not mean safe and afebrile does not mean well. Third, risk stratification sets everything that follows: the high-risk child stays on inpatient intravenous therapy for the duration of the neutropenia, while the carefully selected low-risk child can step down to oral therapy and, with a real safety-net, complete the course as an outpatient. [7][2][1]