[Evaluation dosing intravenous voriconazole three times a day vs twice daily for the treatment of invasive aspergillosis in immunocompromised children: therapeutic drugs monitoring and safety]. / Evaluación de la dosificación de voriconazol intravenoso tres veces al día vs dos veces al día para el tratamiento de aspergilosis invasora en niños inmunocomprometidos: monitorización terapéutica y seguridad.

BACKGROUND: Voriconazole is the antifungal of choice for the treatment of invasive aspergillosis (IA). Plasma concentrations (PCs) > 1 µg / mL llave been associated with better therapeutic results which have not always been achieved during treatment in immunocompromised children. In the necessity to initiate early and effective therapy for the infection, it is relevant to establish the voriconazole administration regimen that is associated with optimal PCs in this population. AIM: To compare the PC and safety of intravenous (IV) voriconazole, dosed BID and TID in immunocompromised children with indication of antifungal treatment. METHOD: Retrospective observational study since January 2015 until July 2018 in a highly complex pediatric hospital in Santiago of Chile, in patients aged 0 to 17 years who received treatment with IV voriconazole. Those with renal replacement therapy, liver failure and / or renal failure were excluded. Trough PCs were compared between a group with BID dosing regimen versus another group with TID administration. Adverse reactions were evaluated in both groups. RESULTS: 137 trough PCs were obtained in 76 children, with a median age of 9 years (0-17 years) in the BID group and 9 years (0-16) in the TID group with a median weight of 27 kg (6-83 kg) and 28 kg (9.3-60 kg), respectively. Patients < 12 years old exposed to TID dosages are 4.65 times (OR: 4.65, 95% CI 1.93-11.2) more likely to have PC > 1 gg/mL compared to BID administration (p = 0.001). Eight adverse reactions were reported, mainly photophobia, with no significant difference found between the BID and TID groups. CONCLUSION: TID dosages are associated with a greater probability of obtaining adequate exposure to voriconazole in patients < 12 years old compared to BID dosages, with a low frequency of adverse reactions.

Evaluación de la dosificación de voriconazol intravenoso tres veces al día vs dos veces al día para el tratamiento de aspergilosis invasora en niños inmunocomprometidos: monitorización terapéutica y seguridad / Evaluation dosing intravenous voriconazole three times a day vs twice daily for the treatment of invasive aspergillosis in immunocompromised children: therapeutic drugs monitoring and safety

INTRODUCCIÓN: Voriconazol es el antifúngico de elección para el tratamiento de la aspergilosis invasora (AI). Concentraciones plasmáticas (CPs) > 1 μg/mL se han asociado a mejores resultados terapéuticos, las que no siempre se alcanzan durante el tratamiento en niños inmunocomprometidos. Dada la necesidad de iniciar una terapia precoz y efectiva de la infección, es relevante establecer el régimen de administración de voriconazol que se asocie con CPs óptimas en esta población. OBJETIVO: Comparar las CPs y seguridad de voriconazol intravenoso (IV), dosificado BID y TID en niños inmunocomprometidos con indicación de tratamiento antifúngico. MÉTODO: Estudio observacional retrospectivo de enero de 2015 a julio de 2018 en un hospital pediátrico de alta complejidad de Santiago de Chile, en pacientes de 0 a 17 años que recibieron tratamiento con voriconazol IV. Se excluyeron aquellos con terapia de reemplazo renal, falla hepática y/o falla renal. Se compararon las CPs valles entre un grupo con régimen de dosificación BID y otro grupo con administración TID. Se evaluaron las reacciones adversas en ambos grupos. RESULTADOS: Se obtuvieron 137 CPs valles en 76 niños, con una mediana de edad de 9 años (0-17 años) en el grupo BID y 9 años (0-16 años) en el grupo TID, con una mediana de peso de 27 kg (6-83 kg) y 28 kg (9,3-60 kg), respectivamente. Resultados: Pacientes 1 gg/mL en comparación con la administración BID (p = 0,001). Se reportaron ocho reacciones adversas, principalmente fotofobia, sin encontrarse diferencias significativas entre grupo BID y TID. CONCLUSIÓN: Dosificaciones TID están asociadas a una mayor probabilidad de obtener una adecuada exposición a voriconazol en pacientes < 12 años en comparación a dosificaciones BID, con baja frecuencia de reacciones adversas.

BACKGROUND: Voriconazole is the antifungal of choice for the treatment of invasive aspergillosis (IA). Plasma concentrations (PCs) > 1 μg / mL llave been associated with better therapeutic results which have not always been achieved during treatment in immunocompromised children. In the necessity to initiate early and effective therapy for the infection, it is relevant to establish the voriconazole administration regimen that is associated with optimal PCs in this population. AIM: To compare the PC and safety of intravenous (IV) voriconazole, dosed BID and TID in immunocompromised children with indication of antifungal treatment. METHOD: Retrospective observational study since January 2015 until July 2018 in a highly complex pediatric hospital in Santiago of Chile, in patients aged 0 to 17 years who received treatment with IV voriconazole. Those with renal replacement therapy, liver failure and / or renal failure were excluded. Trough PCs were compared between a group with BID dosing regimen versus another group with TID administration. Adverse reactions were evaluated in both groups. RESULTS: 137 trough PCs were obtained in 76 children, with a median age of 9 years (0-17 years) in the BID group and 9 years (0-16) in the TID group with a median weight of 27 kg (6-83 kg) and 28 kg (9.3-60 kg), respectively. Patients 1 gg/mL compared to BID administration (p = 0.001). Eight adverse reactions were reported, mainly photophobia, with no significant difference found between the BID and TID groups. CONCLUSION: TID dosages are associated with a greater probability of obtaining adequate exposure to voriconazole in patients < 12 years old compared to BID dosages, with a low frequency of adverse reactions.

Invasive meningococcal disease in Chile seven years after ACWY conjugate vaccine introduction.

BACKGROUND: A serogroup W (MenW) outbreak in Chile prompted a meningococcal vaccination campaign using tetravalent meningococcal-conjugate vaccines (MCV-ACWY) in children since 2012, followed by its introduction into the National Immunization Program (NIP) in toddlers from 2014. Direct protection was observed, but no indirect effects in other age-groups were evidenced. The aim of this study was to describe invasive meningococcal disease (IMD) cases in Chile between 2009 and 2019, and its trend after the introduction of MCV-ACWYs. METHODS: IMD cases, cumulative incidence per 100,000 inhabitants, CFR, and vaccination uptake were described. Data were obtained from the Public Health Institute and NIP. RESULTS: Overall-IMD cases increased in 2009-2014 period, followed by a decline in 2015-2019, focused in infants, children <5 years and people ≥60 years. Serogroup B (MenB) and MenW alternate its predominance. Median overall incidence was 0.6/100,000, increasing from 0.6/100,000 in 2009 to 0.8/100,000 in 2014, later decreasing to 0.4/100,000 in 2019. Median incidences for MenB, serogroup C (MenC) and Y (MenY) were 0.25/100,000, <0.01/100,000 and <0.01/100,000, respectively. Median MenW incidence was 0.53/100,000, increasing from 0.01/100,000 in 2009 to 0.56/100,000 in 2014, followed by a constant decline to 0.12 in 2019. Infants, children <5 years and adults ≥60 years were affected the most, with median incidences of 9.7, 0.9 and 0.93, decreasing to 1.3, 0.1 and 0.1/100,000 in 2019, respectively. Median overall-CFR was 19%, 7.5% for MenB and 24.5% for MenW. Median MCV-ACWY uptake was 93% CONCLUSION: Overall-IMD, MenW cases and incidence declined since 2015 after the MCV-ACWY introduction, while MenB, MenC and MenY have been stable. MenW incidence declined in all age groups, including non-immunized infants and people >60 years. Further analysis and a longer period of observation are needed to have a more robust conclusion about this epidemiological trend. By 2019, CFR remains high.

[Sinus infection caused by Exserohilum rostratum in a pediatric patient with acute myeloid leukemia]. / Infección rino-sinusal por Exserohilum rostratum en un niño con leucemia mieloide aguda.

The episodes of febrile neutropenia are severe cases that require an exhaustive etiological study and a quick start of antimicrobial agents. Within the possible microorganisms, fungal origins are also found, and depending on its tissue invasion, they can reach a high mortality rate. A case of a pediatric patient who suffered from acute myeloid leukemia is reported, and after his induction chemotherapy, the patient showed an episode of febrile neutropenia, which matches a rhinosinusal infection caused by Exserohilum rostratum, a filamentous fungi that is uncommonly associated with pathological cases. An antifungal therapy and an early surgical treatment were started, which lead to a positive response, without complications to the patient. After the monitoring and receiving secondary prophylaxis during the episodes of neutropenia, the patient hasn't presented new injuries nor rhinosinusal damage.

Infección rino-sinusal por Exserohilum rostratum en un niño con leucemia mieloide aguda / Sinus infection caused by Exserohilum rostratum in a pediatric patient with acute myeloid leukemia

Resumen Los episodios de neutropenia febril son cuadros graves, que requieren un estudio etiológico exhaustivo y un inicio rápido de antimicrobianos. Dentro de los posibles microorganismos causales se encuentran los de origen fúngico, los que, dependiendo de su grado de invasión tisular, pueden llegar a presentar una alta mortalidad. Presentamos el caso de un niño con una leucemia mieloide aguda, que tras su quimioterapia de inducción, presentó un episodio de neutropenia febril, con una infección rino-sinusal por Exserohilum rostratum, hongo filamentoso que raramente se asocia a cuadros patológicos. Se inició rápidamente terapia antifúngica, lo cual, asociado a un aseo quirúrgico precoz, lograron una respuesta clínica favorable, sin complicaciones. Luego del seguimiento, y tras recibir profilaxis secundaria durante los episodios de neutropenia, no ha vuelto a presentar nuevas lesiones ni compromiso rino-sinusal.

Abstract The episodes of febrile neutropenia are severe cases that require an exhaustive etiological study and a quick start of antimicrobial agents. Within the possible microorganisms, fungal origins are also found, and depending on its tissue invasion, they can reach a high mortality rate. A case of a pediatric patient who suffered from acute myeloid leukemia is reported, and after his induction chemotherapy, the patient showed an episode of febrile neutropenia, which matches a rhinosinusal infection caused by Exserohilum rostratum, a filamentous fungi that is uncommonly associated with pathological cases. An antifungal therapy and an early surgical treatment were started, which lead to a positive response, without complications to the patient. After the monitoring and receiving secondary prophylaxis during the episodes of neutropenia, the patient hasn't presented new injuries nor rhinosinusal damage.

Meningococcal invasive disease by serogroup W and use of ACWY conjugate vaccines as control strategy in Chile.

BACKGROUND: Serogroup causing invasive meningococcal disease (IMD) can change abruptly, as it occurred in Chile when serogroup predominance switched from MenB to MenW in 2012. As a response, a national vaccination strategy was implemented since 2012 using tetravalent meningococcal-conjugate vaccines (MCV-ACWY) in children 9 months through 4 years of age. The aim of this study was to describe IMD cases by MenW in Chile 2009-2016, and to analyse its trend after the introduction of MCV-ACWY. METHODS: Descriptive study of IMD cases in Chile, period 2009-2016. Cumulative incidence and mortality rate per 100,000 inhabitants, and case fatality rate (CRF) were used for descriptive analysis. Linear regression was used for post-intervention trend analysis. RESULTS: In 2012, MenW, mainly ST-11 cc, became predominant. MenW incidence rose from 0.01/100,000 inhabitants in 2009 to a maximum of 0.6/100,000 in 2015. Infants and adults 80 years of age and older were mostly affected, with an incidence peak of 9.7/100,000 and 1.6/100,000, respectively, in 2015. In the group of children from 1 to 4 years of age MenW incidence declined from 1.3/100,000 in 2012 to 0.1/100,000 in 2016, a 92.3% reduction after vaccination implementation. In the same period and age-cohort, CFR decreased from 23% to 0%. High mortality rates concentrated in infants and adults 80 years of age and over. CONCLUSION: MenW became predominant in Chile since 2012. IMD cases increased steadily from 2009 to 2016, with higher incidence, CFR and mortality concentrating in infants and people 80 years of age and older. MCV-ACWY provided direct protection against MenW, reducing its incidence after mass meningococcal vaccine implementation. Indirect effects of vaccination are not yet observed.

[From a pathogen's genome to an effective vaccine: the four-component meningococcal serogroup B vaccine]. / Del genoma de un patógeno a una vacuna efectiva: la vacuna de cuatro componentes frente a los meningococos del serogrupo B.

Invasive meningococcal disease (IMD), caused by the bacterium Neisseria meningitidis, entails significant mortality and morbidity. Disease incidence is highest in infants <1 year and young children globally. In Europe, N. meningitidis serogroup B is responsible for over 50% of overall IMD cases, whereas the majority of IMD cases in Latin America is caused either by serogroup B or C. The development of an effective vaccine against serogroup B has challenged the researchers for over half a century. Serogroup B capsular polysaccharide was an inappropriate vaccine antigen, and the success of outer membrane vesicle (OMV) vaccines was restricted to homologous bacterial strains. Reverse vaccinology led to the development of a 4-component meningococcal vaccine including three novel antigens, and OMVs (4CMenB). Each vaccine component has a different target. 4CMenB has been authorised based on its immunogenicity and safety data because the low disease incidence precluded formal clinical efficacy studies. Human serum bactericidal antibody (hSBA) assay tests functional antibodies in the serum of vaccinated individuals (i.e. the vaccine immunogenicity), and is the accepted correlate of protection. Vaccine strain coverage has been assessed both through hSBA assays and a more conservative method named Meningococcal Antigen Typing System (MATS). Effectiveness data of 4CMenB have been collected in the field since 2013. The vaccine proved effective in outbreak control in North America, and recent data from the introduction of the vaccine in the United Kingdom infant national immunisation programme reveal a vaccine effectiveness of 82.9% for the first two doses, with an acceptable safety profile.

[Microorganisms isolated from blood cultures in children with cancer and high-risk febrile neutropenia from five hospitals in Santiago, Chile, 2012-2015]. / Microorganismos aislados de hemocultivos en niños con cáncer y neutropenia febril de alto riesgo en cinco hospitales de Santiago, Chile, período 2012-2015.

BACKGROUND: Microorganisms isolated from blood cultures (BC) in patients with febrile neutropenia (NF) vary over time, requiring systematic monitoring to guide appropriate empirical therapy. AIM: To identify microorganisms isolated from BC and their antimicrobial resistance profile in children with cancer and high risk NF. METHOD: Prospective, multicenter study. The analysis included episodes of high-risk FN with positive BC in children under 18 years of age treated in five hospitals in Santiago, Chile, 2012-2015. RESULTS: A total of 206 microorganisms were analyzed in 185 episodes of high-risk FN. The main isolates were Gram negative bacilli (46.6%) and Gram positive cocci (45.1%) and the most frequent microorganisms were Escherichia coli (22.8%), coagulase negative Staphylococcus (18.0%) and Klebsiella spp. (16.5%). Escherichia coli and Klebsiella spp showed 4.2% and 67.6% resistance to third generation cephalosporins (cefotaxime/ceftriaxone), 10.6% and 40.6% resistance to fluoroquinolones (ciprofloxacin) and 2.1% and 26.5% to amikacin, respectively. Coagulase negative Staphylococcus and Staphylococcus aureus had 86.4% and 22.2% resistance to oxacillin, Streptococcus viridans group had 71% resistance to penicillin. DISCUSSION: This study updates the etiology and resistance profile of microorganisms isolated in BC from children with cancer and high risk FN, an essential tool for the adequate management of these patients.

[Pharmacokinetics of posaconazol in the prophylaxis and treatment of invasive fungal infection in immunocompromised children in a pediatric hospital]. / Farmacocinética de posaconazol en la profilaxis y tratamiento de la infección fúngica invasora en niños inmunocomprometidos en un hospital pediátrico.

Background There is no consensus on the optimal dosage use of posaconazole (PSC) for invasive fungal infection (IFI) in pediatric patients and normally it is adjusted with drug levels (DLs) ≥ 0.7 µg/ml and ≥ 1.25 µg/ml for prophylaxis and treatment, respectively. Objective To describe the experience of monitoring DLs of PSC in immunocompromised pediatric patients with IFI and to determine if the recommended doses reach CP effective in prophylaxis (≥ 0.7 µg/mL) and treatment (≥ 1.25 µg/mL). Method A retrospective analysis in children who received PSC from January 2012 to October 2016, in the Oncology and Bone Marrow Transplant units at Hospital Calvo Mackenna was done Six patients with 78 DLs were reviewed (4 prophylaxis and 4 treatment). Median PSC dose was 12.5 and 18.8 mg/kg/d for prophylaxis and treatment, resulting in mean DLs of 0.97 and 1.8 µg/mL respectively. In prophylaxis 40/67 (60%) were recorded with DLs ≥ 0.70 µg/mL receiving a median dose of 12.5 mg/kg/d. While for treatment: 5/11 (46%) presented DLs ≥ 1.25 µg/mL, receiving a median dose of 18 mg/kg/d. Conclusion Our results are in line with the recommended for PSC dosage, but individualized monitoring is required to maintain adequate DLs.

Microorganismos aislados de hemocultivos en niños con cáncer y neutropenia febril de alto riesgo en cinco hospitales de Santiago, Chile, período 2012-2015 / Microorganisms isolated from blood cultures in children with cancer and high-risk febrile neutropenia from five hospitals in Santiago, Chile, 2012-2015

Resumen Antecedentes: Los microorganismos aislados de hemocultivos (HC) en pacientes con neutropenia febril (NF) varían en el tiempo, siendo necesaria su vigilancia para orientar una terapia empírica adecuada. Objetivo: Identificar microorganismos aislados de HC y su perfil de resistencia (R) a antimicrobianos en niños con cáncer y NF de alto riesgo. Método: Estudio prospectivo, multicéntrico de episodios de NF de alto riesgo en pacientes bajo 18 años de edad, de cinco hospitales en Santiago de Chile, 2012-2015. Análisis de HC positivos. Resultados: Se analizaron 206 microorganismos en 185 episodios de NF de alto riesgo con HC positivos. Los aislados principales fueron bacilos gramnegativos (BGN) (46,6%) y cocáceas grampositivas (CGP) (45,1%) y los microorganismos más frecuentes Escherichia coli (22,8%), Staphylococcus coagulasa negativa (18,0%) y Klebsiella spp (16,5%). En resistencia (R) a antimicrobianos destaca: E. coli y Klebsiella spp 4,2 y 67,6% R a cefalosporinas de tercera generación (cefotaxima/ceftriaxona) respectivamente, 10,6 y 40,6% R a ciprofloxacina y 2,1 y 26,5% a amikacina, respectivamente. S. coagulasa negativa y S. aureus 86,4% y 22,2% R a oxacilina, Streptococcus grupo viridans 71% R a penicilina. Discusión: Este estudio actualiza la etiología y el perfil de R de microorganismos aislados en HC de niños con cáncer y NF de alto riesgo, herramienta esencial para el adecuado manejo de estos pacientes.

Background: Microorganisms isolated from blood cultures (BC) in patients with febrile neutropenia (NF) vary over time, requiring systematic monitoring to guide appropriate empirical therapy. Aim: To identify microorganisms isolated from BC and their antimicrobial resistance profile in children with cancer and high risk NF. Method: Prospective, multicenter study. The analysis included episodes of high-risk FN with positive BC in children under 18 years of age treated in five hospitals in Santiago, Chile, 2012-2015. Results: A total of 206 microorganisms were analyzed in 185 episodes of high-risk FN. The main isolates were Gram negative bacilli (46.6%) and Gram positive cocci (45.1%) and the most frequent microorganisms were Escherichia coli (22.8%), coagulase negative Staphylococcus (18.0%) and Klebsiella spp. (16.5%). Escherichia coli and Klebsiella spp showed 4.2% and 67.6% resistance to third generation cephalosporins (cefotaxime/ceftriaxone), 10.6% and 40.6% resistance to fluoroquinolones (ciprofloxacin) and 2.1% and 26.5% to amikacin, respectively. Coagulase negative Staphylococcus and Staphylococcus aureus had 86.4% and 22.2% resistance to oxacillin, Streptococcus viridans group had 71% resistance to penicillin. Discussion: This study updates the etiology and resistance profile of microorganisms isolated in BC from children with cancer and high risk FN, an essential tool for the adequate management of these patients.

Farmacocinética de posaconazol en la profilaxis y tratamiento de la infección fúngica invasora en niños inmunocomprometidos en un hospital pediátrico / Pharmacokinetics of posaconazol in the prophylaxis and treatment of invasive fungal infection in immunocompromised children in a pediatric hospital

Resumen Introducción En pediatría no existe consenso en la dosificación de posaconazol (PSC) para profilaxis y tratamiento de la infección fúngica invasora (IFI), usándose la medición de concentraciones plasmáticas (CPs) del fármaco. Objetivo Describir la experiencia de monitoreo de las CPs de PSC en niños inmunocomprometidos con IFI y determinar si las dosis recomendadas alcanzan CPs efectivas en profilaxis (≥ 0,7 µg/mL) y tratamiento (≥ 1,25 µg/mL). Método Análisis retrospectivo en niños que recibieron PSC suspensión como profilaxis o tratamiento entre enero de 2012 y octubre de 2016, en las unidades de Oncología y Trasplante de Médula Ósea del Hospital Calvo Mackenna. Resultados 78 CPs en seis pacientes (4 indicaciones de profilaxis y 4 tratamientos) fueron revisados. La mediana de dosis de PSC fue de 12,5 y 18,8 mg/kg/d para profilaxis y tratamiento, respectivamente, resultando CP mediana de 0,97 y 1,8 μg/mL, respectivamente. En profilaxis, se registraron 40/67 (60%) con CP ≥ 0,70 μg/mL recibiendo una mediana de dosis de 12,5 mg/kg/d. Mientras que para el tratamiento: 5/11 (46%), presentaron CP ≥ 1,25 μg/mL, recibiendo una mediana de dosis de 18 mg/kg/d. Conclusión Nuestros resultados se ajustan a lo recomendado para la dosificación de PSC, pero evidencian una necesidad de realizar una monitorización individualizada para mantener adecuadas CPs.

Background There is no consensus on the optimal dosage use of posaconazole (PSC) for invasive fungal infection (IFI) in pediatric patients and normally it is adjusted with drug levels (DLs) ≥ 0.7 μg/ml and ≥ 1.25 μg/ml for prophylaxis and treatment, respectively. Objective To describe the experience of monitoring DLs of PSC in immunocompromised pediatric patients with IFI and to determine if the recommended doses reach CP effective in prophylaxis (≥ 0.7 μg/mL) and treatment (≥ 1.25 μg/mL). Method A retrospective analysis in children who received PSC from January 2012 to October 2016, in the Oncology and Bone Marrow Transplant units at Hospital Calvo Mackenna was done Six patients with 78 DLs were reviewed (4 prophylaxis and 4 treatment). Median PSC dose was 12.5 and 18.8 mg/kg/d for prophylaxis and treatment, resulting in mean DLs of 0.97 and 1.8 μg/mL respectively. In prophylaxis 40/67 (60%) were recorded with DLs ≥ 0.70 μg/mL receiving a median dose of 12.5 mg/kg/d. While for treatment: 5/11 (46%) presented DLs ≥ 1.25 μg/mL, receiving a median dose of 18 mg/kg/d. Conclusion Our results are in line with the recommended for PSC dosage, but individualized monitoring is required to maintain adequate DLs.

[Drug interaction of voriconazole-cyclosporine in children undergoing hematopoietic stem cell transplantation (2013-2014)]. / Evaluación de interacción medicamentosa de voriconazol-ciclosporina en pacientes pediátricos que reciben trasplante de precursores hematopoyéticos (2013-2014).

BACKGROUND: Drug interactions (DI) in patients receiving hematopoietic stem cell transplantation (HSCT) are common and clinically significant, highlighting: anticonvulsants, voriconazole (VCZ) and cyclosporine (CsA), which require monitoring. OBJECTIVE: To describe the interactions between CsA-VCZ in children undergoing HSCT. METHODS: Retrospective, descriptive study in immunocompromised children hospitalized since January 2013 to December 2014 at Bone Marrow Transplant Unit, Hospital Dr. Luis Calvo Mackenna, who received CsA and VCZ. RESULTS: The median age was 5 years (3-6) and the median weight was 20 kg (17-30). Sixtythree baseline drug levels were analyzed, of those, 27 were CsA drug levels obtained previous to using VCZ and 36 were CsA drug levels collected concomitantly with VCZ. In the group CsA previous to VCZ, the CsA dose was 4.6 ± 2.6 (mg/ kg/ day) and the CsA average level was 188.8 ± 84.1 (µg/ml). In the group of CsA concomitantly with VCZ, the dose of CsA was 5.5 ± 3.0 (mg/ kg/day) (p = 0.07) and CsA average level was significantly higher: 232.5 ± 106.7 (µg/ml) (p = 0.04). CONCLUSION: This study shows an increased level of CsA when it is used together with VCZ. Therapeutic drug monitoring could improve the management of the DI and optimize the co-administration of CsA and VCZ.

Evaluación de interacción medicamentosa de voriconazol-ciclosporina en pacientes pediátricos que reciben trasplante de precursores hematopoyéticos (2013-2014) / Drug interaction of voriconazole-cyclosporine in children undergoing hematopoietic stem cell transplantation (2013-2014)

Background: Drug interactions (DI) in patients receiving hematopoietic stem cell transplantation (HSCT) are common and clinically significant, highlighting: anticonvulsants, voriconazole (VCZ) and cyclosporine (CsA), which require monitoring. Objective: To describe the interactions between CsA-VCZ in children undergoing HSCT. Methods: Retrospective, descriptive study in immunocompromised children hospitalized since January 2013 to December 2014 at Bone Marrow Transplant Unit, Hospital Dr. Luis Calvo Mackenna, who received CsA and VCZ. Results: The median age was 5 years (3-6) and the median weight was 20 kg (17-30). Sixtythree baseline drug levels were analyzed, of those, 27 were CsA drug levels obtained previous to using VCZ and 36 were CsA drug levels collected concomitantly with VCZ. In the group CsA previous to VCZ, the CsA dose was 4.6 ± 2.6 (mg/ kg/ day) and the CsA average level was 188.8 ± 84.1 (μg/ml). In the group of CsA concomitantly with VCZ, the dose of CsA was 5.5 ± 3.0 (mg/ kg/day) (p = 0.07) and CsA average level was significantly higher: 232.5 ± 106.7 (μg/ml) (p = 0.04). Conclusion: This study shows an increased level of CsA when it is used together with VCZ. Therapeutic drug monitoring could improve the management of the DI and optimize the co-administration of CsA and VCZ.

Introducción: Las interacciones medicamentosas (IM) en el trasplante de progenitores hematopoyéticos (TPH) son comunes y clínicamente significativas, especialmente en: anticonvulsivantes, voriconazol (VCZ) y ciclosporina (CsA). Objetivo: Describir las interacciones de CsA-VCZ en pacientes con TPH. Métodos: Estudio descriptivo, retrospectivo, en pacientes receptores de TPH entre enero de 2013 y diciembre de 2014 en la Unidad de Trasplante de Médula Ósea del Hospital Dr. Luis Calvo Mackenna, que recibieran CsA y VCZ. Resultados: Edad media: 5 años (3-6), peso promedio: 20 kg (17-30). Se analizaron 63 concentraciones plasmáticas de CsA, 27 eran concentraciones de CsA previas al uso de VCZ y 36 concentraciones plasmáticas de CsA concomitantes con VCZ. En el grupo de CsA previo a VCZ, la dosis de CsA fue 4,6 ± 2,6 (mg/kg/día) y la concentración media de CsA 188,8 ± 84,1 (μg/ml). En el grupo de CsA en forma concomitante con VCZ, la dosis de CsA fue de 5,5 ± 3,0 (mg/kg/día) (p 0,07) y la concentración media de CsA fue: 232,5 ± 106,7 (μg/ml) (p = 0,04). Conclusión: Se demostró un aumento de las concentraciones plasmáticas de CsA en IM con VCZ. La monitorización terapéutica podría mejorar el manejo de la IM y optimizar la coadministración de CsA y VCZ.

Evaluating the appropriateness of a community pharmacy model for a colorectal cancer screening program in Catalonia (Spain).

Background The traditional model of community pharmacy has changed, with patients, caregivers and consumers having access to many cognitive services other than the traditional dispensing and supply of medicines. In December 2009, a population-based colorectal cancer screening program started in Barcelona, introducing the community pharmacist and the professional expertise of the pharmacist into the organisational model. Aim To evaluate the program implementation process in the pharmacies, identify barriers and facilitators, and know the opinion of the professionals involved in the colorectal cancer screening program in Catalonia (Spain). Methods Cross-sectional study of the pharmacies that participated in the first round of the program during the first and second trimester of 2010 in Barcelona. A validated questionnaire was used to analyse several functional aspects in the implementation process. Qualitative aspects about the opinion of the pharmacist were studied. A descriptive and bivariate analysis was performed. Results All the pharmacies involved in the program (n = 74) participated in the study. The majority of the sample population was composed of women (70.3%), mean age 44.9 years, and most of them (74%) had attended a specific training session. Pharmacists considered their participation in the program to be an added value to their professional role and a way to increase consumer's confidence on this kind of services. The average time to provide the service was estimated to be less than 10 minutes per consumer. Only three (4.1%) pharmacists considered that the program involved a lot of extra work in the daily activities of the pharmacy. The level of satisfaction of the pharmacists was very high. Conclusions Community pharmacies can be a successful alternative and great resource to implement a population cancer screening program. This functional model can improve the accessibility and participation rates on target population. The level of motivation of the community pharmacist, the specific training program and the perception to give a better care for their patients can be an enabler.

Efficacy and safety of withholding antimicrobial treatment in children with cancer, fever and neutropenia, with a demonstrated viral respiratory infection: a randomized clinical trial.

OBJECTIVES: To determine efficacy and safety of withholding antimicrobials in children with cancer, fever and neutropenia (FN) with a demonstrated respiratory viral infection. METHODS: Prospective, multicentre, randomized study in children presenting with FN at five hospitals in Santiago, Chile, evaluated at admission for diagnosis of bacterial and viral pathogens including PCR-microarray for 17 respiratory viruses. Children positive for a respiratory virus, negative for a bacterial pathogen and with a favourable evolution after 48 h of antimicrobial therapy were randomized to either maintain or withhold antimicrobials. Primary endpoint was percentage of episodes with uneventful resolution. Secondary endpoints were days of fever/hospitalization, bacterial infection, sepsis, admission to paediatric intensive care unit (PICU) and death. RESULTS: A total of 319 of 951 children with FN episodes recruited between July 2012 and December 2015 had a respiratory virus as a unique identified microorganism, of which 176 were randomized, 92 to maintain antimicrobials and 84 to withdraw. Median duration of antimicrobial use was 7 days (range 7-9 days) versus 3 days (range 3-4 days), with similar frequency of uneventful resolution (89/92 (97%) and 80/84 (95%), respectively, not significant; OR 1.48; 95% CI 0.32-6.83, p 0.61), and similar number of days of fever (2 versus 1), days of hospitalization (6 versus 6) and bacterial infections throughout the episode (2%-1%), with one case of sepsis requiring admission to PICU in the group that maintained antimicrobials, without any deaths. CONCLUSIONS: The reduction of antimicrobials in children with FN and respiratory viral infections, based on clinical and microbiological/molecular diagnostic criteria, should favour the adoption of evidence-based management strategies in this population.

[Fatal pneumococcal meningitis due to serotype 19 A: A preventable case?]. / Meningitis neumocóccica por serotipo 19 A, de curso fatal: ¿Un caso prevenible?

Invasive pneumococcal disease (IPD) remains as an important cause of morbidity in the world and in our country, while in Chile the incidence has decreased after the incorporation of the 10 valent pneumococcal conjugate vaccine, in the routine infant inmunization schedule (EPI). One of the expected effects of the program after vaccination with 10-valent pneumococcal vaccine is the likely replacement serotype phenomenon that means the presence of ENI caused by serotypes not included in the vaccine. In this context, we present the case of a child with pneumococcal meningitis caused by serotype 19 A of fatal course. The occurrence of ENI in a later stage of pneumococcal vaccine incorporation in Chile reinforces the importance of active surveillance, in order to know in detail the impact of vaccination, distribution of circulating serotypes and their correlation with the different clinical disease and their severity.

Meningitis neumocóccica por serotipo 19 A, de curso fatal: ¿Un caso prevenible? / Fatal pneumococcal meningitis due to serotype 19 A: A preventable case?

Invasive pneumococcal disease (IPD) remains as an important cause of morbidity in the world and in our country, while in Chile the incidence has decreased after the incorporation of the 10 valent pneumococcal conju-gate vaccine, in the routine infant inmunization schedule (EPI). One of the expected effects of the program after vaccination with 10-valent pneumococcal vaccine is the likely replacement serotype phenomenon that means the presence of ENI caused by serotypes not included in the vaccine. In this context, we present the case of a child with pneumococcal meningitis caused by serotype 19 A of fatal course. The occurrence of ENI in a later stage of pneumococcal vaccine incorporation in Chile reinforces the importance of active surveillance, in order to know in detail the impact of vaccination, distribution of circulating serotypes and their correlation with the different clinical disease and their severity.

La enfermedad neumocóccica invasora (ENI) sigue siendo una causa importante de morbilidad en el mundo y en nuestro país, si bien en Chile la incidencia ha disminuido luego de la incorporación de la vacuna neumocóccica conjugada 10-valente al Programa Nacional de Inmunizaciones (PNI). Uno de los efectos esperables luego de la vacunación programática con la vacuna antineumocóccica 10-valente es el probable fenómeno de reemplazo, que corresponde a la presencia de ENI por serotipos no incluidos en la vacuna. En este contexto, se presenta el caso de un pre-escolar con meningitis neumocóccica causada por el serotipo 19 A, de curso fatal. La presencia de casos de ENI en una etapa posterior a la implementación de la vacuna anti-neumocóccica en el PNI de Chile, demuestra la importancia de realizar una vigilancia activa, con el objetivo de conocer en forma detallada el impacto de la vacunación, la distribución de los serotipos circulantes y su correlación con los diferentes cuadros clínicos y su evolución.

Cost-effectiveness analysis of a multicomponent meningococcal serogroup B vaccine in hypothetic epidemic situation in a middle-income country.

UNLABELLED: NmenB vaccine (4CMenB) is now available, but studies on the cost-effectiveness of vaccine introduction in a country outbreak situation are lacking. The aim of this study was to evaluate the cost-effectiveness of 4CMenB in the context of a hypothetical epidemic outbreak in Chile. We analyzed the direct and indirect costs of acute disease, sequelae and death for each case of meningococcal disease (MD) based on information obtained during the latest NmenB outbreak in Santiago, Chile, occurring between 1993-1999, with an incidence of 5.9/100,000 inhabitants and a mortality of 7.3%. We analyzed the cost of a mass vaccination campaign, considering one dose of 4CMenB for population between 12 months and 25 y of age and 3 doses for infants. Cost-effectiveness analysis was based on 80% and 92% 4CMenB immunogenicity for individual's bellow and over 12 months respectively. Sensitivity analysis was applied to different vaccine costs. RESULTS: The total cost of the epidemic was USD $59,967,351, considering individual cost of each acute case (USD$2,685), sequelae (USD$2,374) and death (USD $408,086). In Chile, the 4CMenB mass vaccination strategy would avoid 215 cases, 61 sequelae, and 16 deaths per year. The strategy would be cost-effective at a vaccine dose cost ≤ of USD$18. CONCLUSIONS: Implementation of a mass vaccination campaign to control a hypothetical NmenB outbreak in Chile would be cost-effective at a vaccine cost per dose ≤ of USD$18. This is the first report of a cost-effectiveness analysis for use of 4CMenB as a single intervention strategy to control an epidemic outbreak of NmenB.

Meningococcal carriage prevalence in university students, 1824 years of age in Santiago, Chile.

INTRODUCTION: Neisseria meningitidis invasive disease is a major public health problem. Pharyngeal carriage is considered a prerequisite for invasive infection. Prevalence reaches 10% in general population and up to 30% in the 20-24 years age group. The aim of this study was to asses pharyngeal carriage prevalence in healthy subjects aged 18-24 years, and as secondary endpoints evaluate known risk factors, to identify serogroups and sequence in the isolated strains. METHODS: Cross-sectional study in 500 healthy subjects; students from Universidad de Chile aged 18-24 years, Santiago, Chile, October 2012. Each subject underwent a risk factor survey prior to throat culture sampling. Samples were processed in one central Microbiology Laboratory of Hospital Luis Calvo Mackenna and serogrouping and sequencing was performed at Instituto de Salud Pública de Chile. RESULTS: We obtained throat samples from 500 healthy subjects, 20 (4%) positive for N. meningitidis. Of positive strains 20% were serogroup B, 15% W and the rest non groupable. The median age was 20 years, 50% were men. Of the risk factors evaluated, 24% were current smokers, 16% shared a room, 72% had kissed someone during the last month, 64% had gone to pub and 76% had consumed alcohol in the same period of time. DISCUSSION: Literatures meningococcal carriage prevalence reaches up to 30% in people aged 18-24 years. Prevalence in our study was 4%. Different interpretations could be given; one could be the absence of overcrowding in our students because of the lack of dorms in our scholar system and also the characteristics of our enrolled group. CONCLUSIONS: Our results suggest the necessity to extend the study to other age groups and to other cities, to better understand the Chilean reality, as well as others regions of America, considering that these results cannot be extrapolated to another countries.

[Mycobacterium tuberculosis infection in a pediatric patient who underwent a hematopoietic stem cell transplant]. / Infección por Mycobacterium tuberculosis en una niña sometida a trasplante de progenitores hematopoyéticos.

We report the case of a 10 year old girl with a relapsed acute lymphoblastic leukemia, who underwent a haploidentical hematopoietic stem cell transplant (HSCT), with grade II skin and digestive graft versus host disease, treated with corticosteroids and cyclosporine. On day + 54, she presented fever, with no other remarkable clinical findings. Imaging study showed the presence of lung and liver nodules, liver biopsy was performed. The study included histology, staining and culture for bacteria and fungi, and the preservation of a piece of tissue at -20°C for future prospective studies. Ziehl Nielsen stain was positive, and study for Mycobacterium infection was performed. Microbiological smears of tracheal and gastric aspirate, and bronchial fluid obtained by bronchoalveolar lavage (BAL) were positive. The final report confirmed Mycobacterium tuberculosis in gastric content, sputum, BAL and liver tissue, susceptible to rifampin, isoniazid, streptomycin and ethambutol, with determination of mutations for genes rpoß and kat G (-). Tuberculosis (TB) diagnosis was confirmed. The girl received daily therapy for two months and then she continued on three times per week therapy for 9 months. Controlled by the transplant, infectious diseases and respiratory teams, the patient remained in good general condition, with radiologic resolution of pulmonary and liver involvement and negative smears. We conclude that Mycobacterium tuberculosis infection should be part of differential diagnosis of febrile illness in patients undergoing HSCT, and biopsy should be a standard practice of early diagnosis in these patients.