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1.
BMC Infect Dis ; 24(1): 1032, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333914

RESUMEN

BACKGROUND: The performance and availability of invasive and non-invasive investigations for the diagnosis of Pneumocystis jirovecii pneumonia (PCP) vary across clinical settings. Estimating the pre-test probability of PCP is essential to the optimal selection and interpretation of diagnostic tests, such as the 1,3-ß-D-glucan assay (BDG), for the prioritization of bronchoscopy, and to guide empiric treatment decisions. We aimed to develop a multivariable risk score to estimate the pre-test probability of PCP. METHODS: The score was developed from a cohort of 626 individuals who underwent bronchoscopy for the purposes of identifying PCP in a Canadian tertiary-care centre, between 2015 and 2018. We conducted a nested case-control study of 57 cases and 228 unmatched controls. Demographic, clinical, laboratory, and radiological data were included in a multivariable logistic regression model to estimate adjusted odds ratios for PCP diagnosis. A clinical risk score was derived from the multivariable model and discrimination was assessed by estimating the score's receiver operating characteristic curve. RESULTS: Participants had a median age of 60 years (interquartile range [IQR] 49-68) and 115 (40%) were female; 40 (14%) had HIV and 49 (17%) had a solid organ transplant (SOT). The risk score included prior SOT or HIV with CD4 ≤ 200/µL (+ 2), serum lactate dehydrogenase ≥ 265.5 IU/mL (+ 2), radiological pattern typical of PCP on chest x-ray (+ 2) or CT scan (+ 2.5), and PCP prophylaxis with trimethoprim-sulfamethoxazole (-3) or other antimicrobials (-2). The median score was 4 points (IQR, 2-4.5) corresponding to a 28% probability of PCP. The risk prediction model had good discrimination with a c-statistic of 0.79 (0.71-0.84). Given the operating characteristics of the BDG assay, scores ≤ 3 in patients without HIV, and ≤ 5.5 in those with HIV, paired with a negative BDG, would be expected to rule out PCP with 95% certainty. CONCLUSION: We propose the PCP Score to estimate pre-test probability of PCP. Once validated, it should help clinicians determine which patients to refer for invasive investigations, when to rely on serological testing, and in whom to consider pre-emptive treatment.


Asunto(s)
Pneumocystis carinii , Neumonía por Pneumocystis , Humanos , Femenino , Masculino , Neumonía por Pneumocystis/diagnóstico , Neumonía por Pneumocystis/microbiología , Persona de Mediana Edad , Estudios de Casos y Controles , Anciano , Pneumocystis carinii/aislamiento & purificación , Factores de Riesgo , Canadá/epidemiología , Broncoscopía , Medición de Riesgo , Hospitalización , Curva ROC , Modelos Logísticos
2.
Pediatr Blood Cancer ; 69(5): e29647, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35253346

RESUMEN

Because they can experience neutropenia due to bone marrow failure, patients with Shwachman-Diamond syndrome (SDS) carry increased risk for serious infections compared with the general population; however, there has been a paucity of data on the incidence and severity of coronavirus disease 2019 (COVID-19) in patients with SDS. We compiled results from a survey distributed to participants in the SDS Registry in May-June 2021. In this report, we describe the characteristics and outcomes of patients with SDS who had COVID-19. Patients reported a short clinical course without significant complications or cytopenias. Additionally, COVID-19 vaccines were well tolerated with minor side effects.


Asunto(s)
Enfermedades de la Médula Ósea , COVID-19 , Insuficiencia Pancreática Exocrina , Neutropenia , COVID-19/complicaciones , Vacunas contra la COVID-19/efectos adversos , Humanos , Síndrome de Shwachman-Diamond , Vacunación
3.
Pediatr Blood Cancer ; 68(12): e29253, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34310027

RESUMEN

BACKGROUND: Fever in neutropenia (FN) remains a frequent complication in pediatric patients undergoing chemotherapy for cancer. Preventive strategies, like primary antibiotic prophylaxis, need to be evidence-based. PROCEDURE: Data on pediatric patients with any malignancy from the prospective multicenter SPOG 2015 FN Definition Study (NCT02324231) were analyzed. A score predicting the risk to develop FN with safety-relevant events (SRE; bacteremia, severe sepsis, intensive care unit admission, death) was developed using multivariate mixed Poisson regression. Its predictive performance was assessed by internal cross-validation and compared with the performance of published rules. RESULTS: In 238 patients, 318 FN episodes were recorded, including 53 (17%) with bacteremia and 68 (21%) with SRE. The risk-prediction score used three variables: chemotherapy intensity, defined according to the expected duration of severe neutropenia, time since diagnosis, and type of malignancy. Its cross-validated performance, assessed by the time needed to cover (TNC) one event, exceeded the performance of published rules. A clinically useful score threshold of ≥11 resulted in 2.3% time at risk and 4.1 months TNC. Using external information on efficacy and timing of intermittent antibiotic prophylaxis, 4.3 months of prophylaxis were needed to prevent one FN with bacteremia, and 5.2 months to prevent one FN with SRE, using a threshold of ≥11. CONCLUSIONS: This score, based on three routinely accessible characteristics, accurately identifies pediatric patients at risk to develop FN with SRE during chemotherapy. The score can help to design clinical decision rules on targeted primary antibiotic prophylaxis and corresponding efficacy studies.


Asunto(s)
Antineoplásicos , Bacteriemia , Neoplasias , Neutropenia , Antibacterianos/efectos adversos , Antineoplásicos/efectos adversos , Bacteriemia/diagnóstico , Niño , Fiebre/diagnóstico , Humanos , Neoplasias/complicaciones , Neoplasias/tratamiento farmacológico , Neutropenia/inducido químicamente , Neutropenia/complicaciones , Neutropenia/prevención & control , Estudios Prospectivos
4.
Pediatr Blood Cancer ; 67(11): e28579, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32893954

RESUMEN

New York City has emerged as one of the epicenters of the SARS-COV-2 pandemic, with the Bronx being disproportionately affected. This novel coronavirus has caused significant respiratory manifestations raising the concern for development of acute chest syndrome (ACS) in patients with sickle cell disease (SCD). We report a series of pediatric SCD SARS-COV-2-positive patients admitted with ACS. SARS-COV-2-positive SCD patients, who did not develop ACS, were the comparison group. Hydroxyurea use (P-value = .02) and lower absolute monocyte counts (P-value = .04) were noted in patients who did not develop ACS. These preliminary findings need to be further evaluated in larger cohorts.


Asunto(s)
Síndrome Torácico Agudo/complicaciones , Anemia de Células Falciformes/complicaciones , COVID-19/complicaciones , Síndrome Torácico Agudo/diagnóstico , Síndrome Torácico Agudo/tratamiento farmacológico , Adolescente , Anemia de Células Falciformes/tratamiento farmacológico , Antibacterianos/uso terapéutico , Antidrepanocíticos/uso terapéutico , COVID-19/diagnóstico , Prueba de COVID-19 , Niño , Doxiciclina/uso terapéutico , Femenino , Hospitales Urbanos , Humanos , Hidroxiurea/uso terapéutico , Masculino , Ciudad de Nueva York , Reacción en Cadena de la Polimerasa , SARS-CoV-2 , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven , Tratamiento Farmacológico de COVID-19
5.
Pediatr Blood Cancer ; 66(12): e27978, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31486593

RESUMEN

BACKGROUND: Pediatric hematology/oncology (PHO) patients receiving therapy or undergoing hematopoietic stem cell transplantation (HSCT) often require a central line and are at risk for bloodstream infections (BSI). There are limited data describing outcomes of BSI in PHO and HSCT patients. METHODS: This is a multicenter (n = 17) retrospective analysis of outcomes of patients who developed a BSI. Centers involved participated in a quality improvement collaborative referred to as the Childhood Cancer and Blood Disorder Network within the Children's Hospital Association. The main outcome measures were all-cause mortality at 3, 10, and 30 days after positive culture date; transfer to the intensive care unit (ICU) within 48 hours of positive culture; and central line removal within seven days of the positive blood culture. RESULTS: Nine hundred fifty-seven BSI were included in the analysis. Three hundred fifty-four BSI (37%) were associated with at least one adverse outcome. All-cause mortality was 1% (n = 9), 3% (n = 26), and 6% (n = 57) at 3, 10, and 30 days after BSI, respectively. In the 165 BSI (17%) associated with admission to the ICU, the median ICU stay was four days (IQR 2-10). Twenty-one percent of all infections (n = 203) were associated with central line removal within seven days of positive blood culture. CONCLUSIONS: BSI in PHO and HSCT patients are associated with adverse outcomes. These data will assist in defining the impact of BSI in this population and demonstrate the need for quality improvement and research efforts to decrease them.


Asunto(s)
Bacteriemia/mortalidad , Infecciones Relacionadas con Catéteres/mortalidad , Cateterismo Venoso Central/mortalidad , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/mortalidad , Hospitalización/estadística & datos numéricos , Infecciones/mortalidad , Adolescente , Bacteriemia/sangre , Bacteriemia/etiología , Infecciones Relacionadas con Catéteres/sangre , Infecciones Relacionadas con Catéteres/etiología , Cateterismo Venoso Central/efectos adversos , Niño , Preescolar , Femenino , Estudios de Seguimiento , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Infecciones/sangre , Infecciones/etiología , Masculino , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
6.
Pediatr Transplant ; 22(7): e13270, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30014584

RESUMEN

Pulmonary mucormycosis diagnosed immediately after hematopoietic stem cell transplantation frequently portends a poor prognosis. However, here we describe two cases in children that were treated successfully to highlight the efficacy of a multidisciplinary approach. Despite diagnosis in the immediate post-transplant period and requirement for ongoing immunosuppression to prevent or treat GVHD, both are long-term survivors due to early surgical debridement with transfusion support and prompt initiation of targeted antifungal therapy. In the absence of evidence-based treatment guidelines, survival of pulmonary mucormycosis is achievable even in high-risk patients with a multidisciplinary team to guide management.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/efectos adversos , Huésped Inmunocomprometido , Inmunosupresores/efectos adversos , Enfermedades Pulmonares Fúngicas/terapia , Mucormicosis/terapia , Infecciones Oportunistas/terapia , Adolescente , Antifúngicos/uso terapéutico , Niño , Terapia Combinada , Desbridamiento , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Inmunosupresores/uso terapéutico , Enfermedades Pulmonares Fúngicas/diagnóstico , Enfermedades Pulmonares Fúngicas/inmunología , Masculino , Mucormicosis/diagnóstico , Mucormicosis/inmunología , Infecciones Oportunistas/diagnóstico , Infecciones Oportunistas/inmunología
7.
Pediatr Blood Cancer ; 65(1)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28696047

RESUMEN

BACKGROUND: The neutropenic diet (ND) is prescribed to avoid introduction of bacteria into a host's gastrointestinal tract and reduce infection. Due to a lack of evidence to support the ND, there continues to be debate among pediatric oncologists regarding its usefulness. This prospective randomized controlled trial evaluated the difference in neutropenic infection rates in pediatric oncology patients randomized to Food and Drug Administration approved food safety guidelines (FSGs) versus the ND plus FSGs during one cycle of chemotherapy. PROCEDURE: Pediatric patients receiving cancer treatment with myelosuppressive chemotherapy were eligible. Neutropenic infection was the primary outcome and defined as (i) fever with neutropenia or (ii) hospital admission and treatment for clinical infection and neutropenia. The rate of neutropenic infection was compared with Student's t-test for independent samples. Documented infections were identified by comprehensive chart review and compared between groups using a χ2 test. RESULTS: One hundred fifty patients were randomly assigned to FSGs (n = 73) or ND + FSGs (n = 77). The most common diagnoses were acute lymphoblastic leukemia (32%) and sarcoma (32%). There was no significant difference between the groups in the percentage of patients who developed neutropenic infection: FSGs 33% versus ND + FSGs 35% (P = 0.78). Patients randomized to ND + FSGs reported that following the diet required more effort than those on FSGs alone. CONCLUSION: The ND offers no benefit over FSGs in the prevention of infection in pediatric oncology patients undergoing myelosuppressive chemotherapy and adherence requires more effort for patients and families. Institutions caring for children with cancer should consider replacing ND guidelines with FSGs.


Asunto(s)
Inocuidad de los Alimentos , Neoplasias/tratamiento farmacológico , Neutropenia , Adolescente , Adulto , Niño , Preescolar , Método Doble Ciego , Femenino , Humanos , Lactante , Infecciones/inducido químicamente , Infecciones/terapia , Masculino , Neutropenia/inducido químicamente , Neutropenia/dietoterapia , Guías de Práctica Clínica como Asunto , Estudios Prospectivos
8.
Pediatr Blood Cancer ; 63(9): 1603-7, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27198806

RESUMEN

BACKGROUND: Central line associated bloodstream infections (CLABSIs) are a significant cause of morbidity and mortality in pediatric hematology/oncology (PHO) patients. Understanding the differences in CLABSI rates by central line (CL) type is important to inform clinical decisions. PROCEDURE: CLABSI, using similar definitions, noted with three commonly used CL types (totally implanted catheter [port], tunneled externalized catheter [TEC], peripherally inserted central catheter [PICC]) and CL-specific line days were prospectively tracked across 15 US PHO centers from May 2012 until April 2015 and CLABSI rates (CLABSI per 1,000 CL-specific line days) were calculated. Host and organism characterstics associated with the CLABSI events were analyzed. RESULTS: Over the course of 2.8 million line days, 1,113 CLABSI events (397 in inpatients and 716 in ambulatory patients) were noted. The inpatient CLABSI rate was higher than the ambulatory CLABSI rate for each of the CL types: 1.48 versus 0.16 for ports, 3.51 versus 1.38 for TECs, and 3.07 versus 1.16 for PICCs, respectively. TECs and PICCs were associated with higher CLABSI rates than ports, inpatient and ambulatory. CONCLUSIONS: We found that CLABSI rates were significantly higher for inpatients compared to ambulatory PHO patients for all CL types. Among ambulatory patients, TECs had the highest CLABSI rate and ports the lowest. Among inpatients, TECs and PICCs had higher CLABSI rates than ports but were not statistically different from one another. Cognizant that host and underlying disease attributes may contribute to these differences, these results can still inform CL choice in clinical practice.


Asunto(s)
Bacteriemia/epidemiología , Infecciones Relacionadas con Catéteres/epidemiología , Cateterismo Venoso Central/efectos adversos , Neoplasias/complicaciones , Niño , Femenino , Humanos , Masculino , Estudios Prospectivos
9.
Pediatr Blood Cancer ; 63(8): 1474-6, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27148941

RESUMEN

We describe a 4-year-old female with pre-B-cell acute lymphoblastic leukemia on maintenance chemotherapy, who developed hemophagocytic lymphohistiocytosis (HLH) secondary to Epstein-Barr virus (EBV) infection, complicated by an aggressive lymphoproliferative disorder. Although there was no history of bone marrow transplant or underlying immunodeficiency, EBV triggered a post-transplant lymphoproliferative disease (PTLD)-like lymphoma. Multiple regimens of chemotherapy failed to induce remission and patient developed multiorgan failure. The association of HLH with EBV-related PTLD-like lymphoproliferative disorder is rare. We present this case to highlight this unusual association so that this highly fatal disease can be recognized and promptly addressed.


Asunto(s)
Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Infecciones por Virus de Epstein-Barr/patología , Huésped Inmunocomprometido , Linfohistiocitosis Hemofagocítica/tratamiento farmacológico , Insuficiencia Multiorgánica/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Antineoplásicos/efectos adversos , Preescolar , Ciclosporina/uso terapéutico , Dexametasona/uso terapéutico , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Etopósido/uso terapéutico , Femenino , Humanos , Lactante , Linfohistiocitosis Hemofagocítica/complicaciones , Masculino , Mercaptopurina/uso terapéutico , Metotrexato/uso terapéutico , Insuficiencia Multiorgánica/complicaciones , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Rituximab/uso terapéutico , Insuficiencia del Tratamiento , Vincristina/uso terapéutico , Carga Viral
10.
Pediatr Blood Cancer ; 63(7): 1244-9, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26970419

RESUMEN

BACKGROUND: The Infectious Diseases Society of America (IDSA) guidelines recommend collecting blood cultures for the first 3 days of febrile neutropenia (FN) in the clinically stable oncology patient with persistent fevers. Nonetheless, many physicians send daily blood cultures beyond 3 days, and the impact of that practice is uncertain. PROCEDURE: We reviewed pediatric FN episodes from July 2009 to May 2014 at University of Chicago Comer Children's Hospital. For each positive culture, we determined if it was a pathogen or a contaminant. We reviewed episode and patient demographics to identify risk factors for subsequent positive blood cultures in the setting of an initially negative culture. RESULTS: We identified 381 episodes of FN in 162 patients. Of those, 87 had a positive blood culture on day 1 (21.0% incidence of bacteremia). Of 294 episodes with a negative blood culture on day 1, six (2.04%, 95% confidence interval [CI] 0.42-3.67) had a positive culture after day 3. Of those, three were pathogens (1.02%, 95%CI -0.14 to 2.18), and only one was found in a hemodynamically stable patient (0.34%, 95%CI -0.33 to 1.01) with new mucositis. In the other two patients, Escherichia coli was isolated from blood cultures after day 10 in the setting of significant hemodynamic changes. Risk factor analysis performed in stable patients yielded nonsignificant results. CONCLUSIONS: Of 294 FN episodes with an initial negative blood culture, only one episode of bacteremia occurred without hemodynamic changes past day 3, supporting the IDSA guidelines to discontinue blood cultures in stable FN patients after day 3.


Asunto(s)
Bacteriemia , Cultivo de Sangre , Neutropenia Febril Inducida por Quimioterapia , Infecciones por Escherichia coli , Escherichia coli , Adhesión a Directriz , Adolescente , Bacteriemia/sangre , Bacteriemia/epidemiología , Bacteriemia/etiología , Bacteriemia/microbiología , Neutropenia Febril Inducida por Quimioterapia/sangre , Neutropenia Febril Inducida por Quimioterapia/epidemiología , Neutropenia Febril Inducida por Quimioterapia/microbiología , Niño , Preescolar , Infecciones por Escherichia coli/sangre , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/etiología , Infecciones por Escherichia coli/microbiología , Femenino , Humanos , Incidencia , Masculino
11.
J Microbiol Immunol Infect ; 49(1): 66-73, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24582464

RESUMEN

PURPOSE: Invasive aspergillosis (IA) is an important cause of morbidity and mortality in immunocompromised patients. Pediatric data on the accuracy and optimal cutoff of galactomannan antigen detection to diagnose IA is sparse and controversial. We evaluated the utility and optimal serum galactomannan assay (GA) cutoff in children. METHODS: Children with febrile neutropenia due to malignancy, hematopoietic stem cell transplant, aplastic anemia, or congenital neutropenia, were prospectively included from 2007 to 2011. All new episodes of febrile neutropenia were recorded. In case of a previous diagnosis of IA, subsequent episodes were excluded. One to four GA were tested by enzyme immunoassay during each episode. Bronchoalveolar lavage and other relevant samples for mycological diagnosis, and computed tomography of chest/sinus were performed wherever appropriate. IA was classified as "proven", "probable", and "possible" as per the 2008 European Organisation for Research and Treatment of Cancer and Mycoses Study Group Guidelines. The optimal cutoff value was determined using receiver operating characteristic curves in episode-wise analysis. RESULTS: There were 145 patients with 211 febrile episodes included: hematopoietic stem cell transplant (n = 15), oncological (n = 113), and hematological disorders (n = 17). Forty-five children (31.0%) developed IA (5 proven, 15 probable, and 25 possible). Cutoff value of single GA ≥ 0.7 for proven/probable/possible IA offered the best combination of sensitivity (82.2%)/specificity (82.5%), and 94.4% negative predictive value. Two consecutive positive GA ≥ 0.7 had a sensitivity/specificity of 75.0%/91.0%. Index GA ≥ 1.9 was associated with significantly higher mortality in children with IA and overall. CONCLUSION: Serum GA is sensitive to diagnose IA in pediatric patients with excellent negative predictive value at an optimal cutoff of ≥0.7. Considering two consecutive values ≥0.7 increases specificity to 91.0%.


Asunto(s)
Antígenos Fúngicos/sangre , Aspergilosis Pulmonar Invasiva/diagnóstico , Mananos/sangre , Neutropenia/complicaciones , Adolescente , Niño , Preescolar , Diagnóstico Precoz , Femenino , Galactosa/análogos & derivados , Humanos , Lactante , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y Especificidad
12.
Pediatr Blood Cancer ; 62(2): 262-268, 2015 02.
Artículo en Inglés | MEDLINE | ID: mdl-25327666

RESUMEN

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.


Asunto(s)
Bacteriemia/diagnóstico , Fiebre/complicaciones , Modelos Teóricos , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Catéteres Venosos Centrales/efectos adversos , Niño , Preescolar , Humanos , Neoplasias/tratamiento farmacológico , Estudios Retrospectivos , Factores de Riesgo
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