Langerhans Cell Histiocytosis of the Gastrointestinal Tract: Evidence for Risk Organ Status.

OBJECTIVE: To investigate the "risk status" of Langerhans cell histiocytosis (LCH) of the gastrointestinal tract. STUDY DESIGN: Outcomes from 43 published cases of patients with LCH and gastrointestinal tract involvement were matched to 43 patients with LCH without gastrointestinal tract involvement cared for at our institution. Comparisons were made of the 5-year overall survival rates determined from Kaplan-Meier survival curves for the entire cohort of patients, as well as subgroups defined by lack of risk organ involvement and later era of treatment (to control for temporal changes in LCH treatment regimens). In addition, an association between LCH-gastrointestinal tract and risk organ involvement was investigated. RESULTS: The 5-year overall survival for children with LCH-gastrointestinal tract (45.3%) was significantly worse than for those without gastrointestinal tract involvement (94.6%; P = .001). This difference remained significant after we excluded risk organ involvement (53.6%% vs 100%; P = .001), and analyzing subjects diagnosed after 2000 (75% vs 100%; P = .012). A 4-fold increase in risk organ involvement with LCH-gastrointestinal tract was observed (OR 4.359; 95% CI 1.75-10.82, P = .001). CONCLUSIONS: This limited retrospective study suggests that patients with LCH-gastrointestinal tract involvement may have decreased survival, independent of risk organ involvement, and provides evidence to support a prospective study to evaluate risk organ status of LCH-gastrointestinal tract. LCH-gastrointestinal tract may be associated with a 4-fold risk for risk organ involvement. Attention to gastrointestinal symptoms and LCH-gastrointestinal tract in young children diagnosed with LCH is warranted.

Development and Initial Validation of the Macrophage Activation Syndrome/Primary Hemophagocytic Lymphohistiocytosis Score, a Diagnostic Tool that Differentiates Primary Hemophagocytic Lymphohistiocytosis from Macrophage Activation Syndrome.

OBJECTIVE: To develop and validate a diagnostic score that assists in discriminating primary hemophagocytic lymphohistiocytosis (pHLH) from macrophage activation syndrome (MAS) related to systemic juvenile idiopathic arthritis. STUDY DESIGN: The clinical, laboratory, and histopathologic features of 362 patients with MAS and 258 patients with pHLH were collected in a multinational collaborative study. Eighty percent of the population was assessed to develop the score and the remaining 20% constituted the validation sample. Variables that entered the best fitted model of logistic regression were assigned a score, based on their statistical weight. The MAS/HLH (MH) score was made up with the individual scores of selected variables. The cutoff in the MH score that discriminated pHLH from MAS best was calculated by means of receiver operating characteristic curve analysis. Score performance was examined in both developmental and validation samples. RESULTS: Six variables composed the MH score: age at onset, neutrophil count, fibrinogen, splenomegaly, platelet count, and hemoglobin. The MH score ranged from 0 to 123, and its median value was 97 (1st-3rd quartile 75-123) and 12 (1st-3rd quartile 11-34) in pHLH and MAS, respectively. The probability of a diagnosis of pHLH ranged from <1% for a score of <11 to >99% for a score of ≥123. A cutoff value of ≥60 revealed the best performance in discriminating pHLH from MAS. CONCLUSION: The MH score is a powerful tool that may aid practitioners to identify patients who are more likely to have pHLH and, thus, could be prioritized for functional and genetic testing.

Evaluation of febrile, nonneutropenic pediatric oncology patients with central venous catheters who are not given empiric antibiotics.

OBJECTIVE: To evaluate the practice of empiric antibiotics for febrile, nonneutropenic pediatric oncology patients with a central venous catheter (CVC) in place. STUDY DESIGN: Episodes of fever without neutropenia (absolute neutrophil count [ANC] ≥500 cells/mm(3)) were reviewed retrospectively in pediatric oncology patients with a CVC undergoing chemotherapy. Characteristics and symptoms were compared between patients with bacteremia and patients without bacteremia. RESULTS: A total of 392 episodes of nonneutropenic fever in 138 subjects (52 females; 38%) were reviewed. In this cohort, the median age at an episode was 7 years, and the majority of patients had a diagnosis of acute leukemia (54%). Median ANC was 3100 cells/mm(3) (IQR, 1570-5980 cells/mm(3)). Median temperature was 38.7°C (IQR, 38.3-39.2°C). Twenty-four infectious episodes (6%) occurred in 18 subjects, and 5 CVCs required removal; all patients requiring removal admitted and received antibiotics owing to chills. There were no significant difference in age, sex, or ANC between patients with bacteremia and those without bacteremia; however, mean temperature was higher in the patients with bacteremia (39.4°C vs 38.7°C; P = .003). No deaths due to sepsis occurred, and no CVCs were removed because antibiotics were not administered empirically. CONCLUSION: Our practice of observing pediatric oncology patients undergoing chemotherapy with CVCs who are not neutropenic does not appear to lead to increased serious adverse outcomes and avoids antibiotic exposure for >90% of patients without a bacterial infection.