Development and validation of a prediction model for diagnosing blood stream infections in febrile, non-neutropenic children with cancer.

BACKGROUND: Pediatric oncology patients are at increased risk for blood stream infections (BSI). Risk in the absence of severe neutropenia (absolute neutrophil count [ANC] ≥500/µl) is not well defined. PROCEDURE: In a retrospective cohort of febrile (temperature ≥38.0° for >1 hr or ≥38.3°) pediatric oncology patients with ANC ≥500/µl, a diagnostic prediction model for BSI was constructed using logistic regression modeling and the following candidate predictors: age, ANC, absolute monocyte count, body temperature, inpatient/outpatient presentation, sex, central venous catheter type, hypotension, chills, cancer diagnosis, stem cell transplant, upper respiratory symptoms, and exposure to cytarabine, anti-thymocyte globulin, or anti-GD2 antibody. The model was internally validated with bootstrapping methods. RESULTS: Among 932 febrile episodes in 463 patients, we identified 91 cases of BSI. Independently significant predictors for BSI were higher body temperature (Odds ratio [OR] 2.36 P < 0.001), tunneled external catheter (OR 13.79 P < 0.001), peripherally inserted central catheter (OR 3.95 P = 0.005), elevated ANC (OR 1.19 P = 0.024), chills (OR 2.09 P = 0.031), and hypotension (OR 3.08 P = 0.004). Acute lymphoblastic leukemia diagnosis (OR 0.34 P = 0.026), increased age (OR 0.70 P = 0.049), and drug exposure (OR 0.08 P < 0.001) were associated with decreased risk for BSI. The risk prediction model had a C-index of 0.898; after bootstrapping adjustment for optimism, corrected C-index 0.885. CONCLUSIONS: We developed a diagnostic prediction model for BSI in febrile pediatric oncology patients without severe neutropenia. External validation is warranted before use in clinical practice. Pediatr Blood Cancer 2015;62:262-268. © 2014 Wiley Periodicals, Inc.

Expression of Hedgehog ligand and signal transduction components in mutually distinct isocitrate dehydrogenase mutant glioma cells supports a role for paracrine signaling.

Hedgehog (Hh) signaling regulates the growth of malignant gliomas by a ligand-dependent mechanism. The cellular source of Sonic Hh ligand and mode of signaling have not been clearly defined due to the lack of methods to definitively identify neoplastic cells in glioma specimens. Using an antibody specific for mutant isocitrate dehydrogenase protein expression to identify glioma cells, we demonstrate that Sonic Hh ligand and the pathway components Patched1 (PTCH1) and GLI1 are expressed in neoplastic cells. Further, Sonic Hh ligand and its transcriptional targets, PTCH1 and GLI1, are expressed in mutually distinct populations of neoplastic cells. These findings support a paracrine mode of intratumoral Hh signaling in malignant gliomas.

Utility of postoperative radiographs for cervical spine fusion: a comprehensive evaluation of operative technique, surgical indication, and duration since surgery.

STUDY DESIGN: A retrospective study. OBJECTIVE: To assess the utility of postoperative radiographs in patients across a spectrum of cervical fusion procedures, surgical indication, and time since surgery. SUMMARY OF BACKGROUND DATA: Postoperative radiographs are routinely obtained after cervical spine fusion despite lack of evidence supporting such practice. Studies assessing postoperative radiographical utility in the cervical spine have been limited. To date, no study has comprehensively evaluated the utility of obtaining such radiographs across multiple cervical fusion procedures. METHODS: A total of 972 clinic notes from 301 patients during a 10-year period at a single institution were retrospectively reviewed. Patients in this study underwent an anterior cervical discectomy and fusion, anterior corpectomy and fusion, a combined anterior cervical discectomy and fusion and anterior corpectomy and fusion (hybrid), posterior spine fusion, or 360° fusion. All postoperative clinic notes and radiographs were reviewed for abnormalities and changes in treatment course. It was determined whether an abnormal radiograph alone led to a change in treatment course among the various operative techniques, surgical indication, or time since surgery. RESULTS: No statistical significant difference in radiograph utility between anterior cervical discectomy and fusion (0 changes in treatment course due to radiograph alone out of 332 clinic notes), anterior corpectomy and fusion (0 of 140), hybrid procedure (1 of 72), posterior spine fusion (5 of 357), and 360° fusion (0 of 71) was found. Surgical indication (trauma vs. degeneration) and duration from surgery yielded no statistical significant difference in radiograph utility. The overall sensitivity, specificity, and positive and negative predictive values of radiographs were 33.8%, 87.6%, 19.0%, and 93.9%, respectively. CONCLUSION: Regardless of operative techniques performed, surgical indication, and time since surgery, routine postoperative radiographs provide low utility in guiding treatment course in asymptomatic patients. Although radiographs may provide important diagnostic utility in certain individual cases, the results of this study provide further evidence that radiographs should not be considered routine during postoperative visits, thus minimizing unnecessary radiation exposure and medical costs.