Urine cultures at the onset of febrile neutropenia rarely impact antibiotic management in asymptomatic adult cancer patients.

PURPOSE: There is a paucity of data regarding the utility of routine urine cultures in adults with febrile neutropenia (FN) without urinary symptoms receiving protocolised antibiotics. This is reflected by inconsistent recommendations in international and regional FN guidelines. We addressed this issue by retrospectively reviewing the impact of routine urine cultures on antibiotic management in haematology cancer inpatients at a tertiary hospital. METHODS: All haematology inpatients over a 5-year period (2011-2015) were retrospectively reviewed for episodes of FN (neutrophil count < 0.5 × 109/L and fever > 37.5 °C). For each episode, demographic data, urinary tract symptoms and signs (absence of which was termed 'asymptomatic'), urinalysis and urine culture results, antibiotic therapy and duration, and patient outcomes were collected. A urine culture was considered positive if > 105 colony forming units (CFU)/L were detected. Empiric antibiotic therapy for FN consisted of intravenous piperacillin/tazobactam in stable patients, with the addition of vancomycin and a single dose of gentamicin if systemically compromised. RESULTS: Four hundred and thirty-three episodes of FN were identified in 317 patients. Urine cultures were performed in 362 (84%) episodes. Cultures were positive in 9 of 48 (19%) symptomatic episodes versus 8 of 314 (2.5%) asymptomatic episodes (RR = 7.4, p < 0.0001). A change in antibiotic management due a positive urine culture occurred in only 5 episodes (1.4%): 3 of 48 (6.3%) symptomatic and 2 of 314 (0.6%) asymptomatic episodes respectively (RR = 9.8, p = 0.01). CONCLUSION: Routine urine cultures in FN patients without urinary symptoms who are already receiving protocolised broad spectrum antibiotics rarely impact subsequent antibiotic management.

Routine blood investigations have limited utility in surveillance of aggressive lymphoma in asymptomatic patients in complete remission.

BACKGROUND: Patients with aggressive lymphoma achieving complete remission (CR) after first-line combination chemotherapy undergo regular surveillance to detect relapse. Current international guidelines recommend routine follow-up blood tests in this context, but evidence supporting this practice is limited. METHODS: We conducted a multi-centre retrospective analysis of all patients diagnosed with aggressive lymphoma treated with curative-intent chemotherapy who achieved CR for at least 3 months between 2000 and 2015. An abnormal blood test was defined as any new and unexplained abnormality for full blood examination, lactate dehydrogenase or erythrocyte sedimentation rate. RESULTS: Three hundred and forty-six patients attended a total of 3084 outpatient visits; blood tests were performed at 90% of these appointments. Fifty-six (16%) patients relapsed. Routine laboratory testing detected relapse in only three patients (5% of relapses); in the remaining patients, relapse was suspected clinically (80%) or detected by imaging (15%). The sensitivity of all blood tests was 42% and the positive predictive value was 9%. No significant difference in survival was shown in patients who underwent a routine blood test within 3 months prior to relapse versus those who did not (p = 0.88). CONCLUSIONS: Routine blood tests demonstrate unacceptably poor performance characteristics, have no impact on survival and thus have limited value in the detection of relapse in routine surveillance.

Echocardiography has low utility in cancer patients with Staphylococcus aureus bacteraemia: findings from a retrospective study.

AIM: To describe the incidence of infective endocarditis (IE) detected on echocardiography in cancer patients with confirmed Staphylococcus aureus bacteraemia (SAB). METHODS: We retrospectively identified 95 cases of SAB in cancer patients from January 2007-March 2016. Echocardiography was ordered at the discretion of the treating team, and positive findings defined according to the Modified Duke Criteria. Complicated bacteraemia was defined by prolonged bacteraemia, presence of intracardiac device/prosthetic valve, or signs of metastatic infection. RESULTS: Major predisposing risk factors for IE (intracardiac device, prosthetic valve, valvular disease, diabetes mellitus, renal dialysis) were present in 27% of cases. Fifty-one of 95 (54%) had a central venous catheter and 17 (18%) patients had complicated bacteraemia. Echocardiography was performed in 75/95 (79%) episodes, with transthoracic echocardiography (TTE) alone in 56, transoesophageal echocardiography (TOE) alone in 4 and both in 15. Echocardiography was diagnostic for IE in 2 patients (1 TTE, 1 TOE), including one result that led to the diagnosis of IE in a clinically unsuspected case. Four further cases of IE were diagnosed on clinical findings, resulting in an overall rate of IE of 6% (6/95). Five of these cases occurred in patients with complicated bacteraemia or ≥ 1 risk factor for IE. No patient was readmitted due to IE. CONCLUSION: IE is infrequent in cancer patients with uncomplicated SAB and no risk factors for IE. Performing echocardiography routinely in all cancer patients with SAB rarely alters diagnosis or affects antibiotic management and therefore should be reserved for patients with specific risk factors.

Limited utility of routine chest X-ray in initial evaluation of neutropenic fever in patients with haematological diseases undergoing chemotherapy.

BACKGROUND: Routine chest X-ray (CXR) is recommended for neutropenic fever (NF) management however its role is relatively understudied in haematology patients. AIM: To investigate the utility of CXR in the diagnosis and management of patients with haematological conditions complicated by NF. METHODS: Retrospective, single-centre analysis of haematology patients admitted with NF between January 2011 and December 2015. Baseline demographics, treatment details and outcomes were collected from electronic patient records. CXR underwent independent radiology review. Primary endpoints were a proportion of NF episodes in which CXR detected a probable chest infection in the absence of respiratory symptoms/signs and/or resulted in a change in antibiotic management. RESULTS: Four hundred and thirty-five episodes were identified; CXR was performed in 75% of patients (65% within 2 days of NF). In 4 of 164 (2.4%) asymptomatic patients, CXR was consistent with infection, in contrast to 19 of 119 (16%) patients with clinical signs of respiratory infection. Only 3 of 283 (1.1%) CXR resulted in a change to antibiotics. CXR consistent with infection was not associated with increased mortality or increased admission length, although there was an association with intensive care unit admission (odds ratios: 7.61, 95% confidence interval: 2.04-28.31). CONCLUSION: In haematology patients with NF, CXR rarely detected chest infection or changed management in patients with no respiratory symptoms or signs. CXR in our institution is no longer part of routine assessment of NF in the absence of these features.

Activation by zinc of the human gastrin gene promoter in colon cancer cells in vitro and in vivo.

Over-expression of growth factors can contribute to the development and progression of cancer, and gastrins in particular have been implicated in accelerating the development of gastrointestinal cancers. Previously our group showed that hypoxia, cobalt chloride (a hypoxia mimetic) and zinc chloride could activate the expression of the gastrin gene in vitro. To characterise activation of the gastrin promoter by zinc ions further in vivo, TALEN technology was used to engineer a luciferase reporter construct into the endogenous human gastrin gene promoter in SW480 colon cancer cells. Gastrin promoter activity in the resultant Gast(luc) SW480 colon cancer cells was then measured by bioluminescence in cell culture and in tumour xenografts in SCID mice. Activation of intracellular signalling pathways was assessed by Western blotting. Activation of the gastrin promoter by zinc ions was concentration dependent in vitro and in vivo. Zinc ions significantly stimulated phosphorylation of ERK1/2 (MAPK pathway) but not of Akt (PI3K pathway). We conclude that the endogenous gastrin promoter is responsive to zinc ions, likely via activation of the MAPK pathway.