Botulismo del lactante: estudio descriptivo en una unidad de cuidados intensivos pediátricos / Infant botulism: a descriptive study in a pediatric intensive care unit

Introducción. El botulismo del lactante (BL) es la forma más frecuente de botulismo humano en Argentina. El objetivo es describir aspectos esenciales del diagnóstico y tratamiento de pacientes con BL internados en el servicio de terapia intensiva pediátrica (STIP). Métodos. Estudio observacional, descriptivo y retrospectivo. Se utilizó la base de datos del STIP con diagnóstico de BL en el período 2005-2020. Se registraron variables demográficas, métodos de diagnóstico, días de asistencia respiratoria mecánica convencional (ARMC), de ventilación no invasiva (VNI), estadía en STIP, mortalidad al alta hospitalaria. Resultados. Se registraron 21 pacientes con BL; 14 pacientes fueron varones, con una mediana de edad de 5 meses (RIC 2-6 m). El diagnóstico se realizó mediante técnica de bioensayo y se detectó la toxina en suero en 12 pacientes. Uno solo no requirió ARMC; 1 paciente fue traqueostomizado; 18 pacientes recibieron antibióticos; 5 recibieron VNI. Ningún paciente recibió antitoxina y no hubo fallecidos. La mediana de estadía hospitalaria fue 66 días (RI: 42-76); de internación en STIP, 48 días (RI: 29-78); y de ARMC, 37 días (RI: 26-64). La demora en la confirmación diagnóstica fue 15,8 ± 4,8 días. Conclusiones. La totalidad de los pacientes fueron diagnosticados con la técnica de bioensayo, que generó un tiempo de demora diagnóstica que excede los lapsos recomendados para la administración del tratamiento específico. Ningún paciente recibió tratamiento específico. El BL presentó baja mortalidad, pero tiempos de ARM e internación prolongados, que se asocian a infecciones sobreagregadas y uso frecuente de antibióticos.

Introduction. Infant botulism (IB) is the most common form of human botulism in Argentina. Our objective was to describe the main aspects of diagnosis and management of patients with IB admitted to the pediatric intensive care unit (PICU). Methods. Observational, descriptive, and retrospective study. The PICU database with IB diagnosis in 2005­2020 period was used. Demographic variables, diagnostic methods, days of conventional mechanical ventilation (CMV), non-invasive ventilation (NIV), length of stay in the PICU and mortality upon hospital discharge were recorded. Results. In total, 21 patients with IB were recorded; 14 were male, their median age was 5 months (IQR: 2­6 m). Diagnosis was made by bioassay, and the toxin was identified in the serum of 12 patients. Only 1 patient did not require CMV; 1 patient had a tracheostomy; 18 patients received antibiotics; 5 received NIV. No patient was administered antitoxin and no patient died. The median length of stay in the hospital was 66 days (IQR: 42­76); in the PICU, 48 days (IQR: 29­78); and the median use of CMV, 37 days (IQR: 26­64). The delay until diagnostic confirmation was 15.8 ± 4.8 days. Conclusions. All patients were diagnosed using the bioassay technique, which resulted in a diagnostic delay that exceeds the recommended period for the administration of a specific treatment. No patient received a specific treatment. IB was related to a low mortality, but also to prolonged use of MV and length of hospital stay, which were associated with cross infections and frequent antibiotic use.

Infant botulism: a descriptive study in a pediatric intensive care unit. / Botulismo del lactante: estudio descriptivo en una unidad de cuidados intensivos pediátricos.

Introduction. Infant botulism (IB) is the most common form of human botulism in Argentina. Our objective was to describe the main aspects of diagnosis and management of patients with IB admitted to the pediatric intensive care unit (PICU). Methods. Observational, descriptive, and retrospective study. The PICU database with IB diagnosis in 2005-2020 period was used. Demographic variables, diagnostic methods, days of conventional mechanical ventilation (CMV), non-invasive ventilation (NIV), length of stay in the PICU and mortality upon hospital discharge were recorded. Results. In total, 21 patients with IB were recorded; 14 were male, their median age was 5 months (IQR: 2-6 m). Diagnosis was made by bioassay, and the toxin was identified in the serum of 12 patients. Only 1 patient did not require CMV; 1 patient had a tracheostomy; 18 patients received antibiotics; 5 received NIV. No patient was administered antitoxin and no patient died. The median length of stay in the hospital was 66 days (IQR: 42-76); in the PICU, 48 days (IQR: 29-78); and the median use of CMV, 37 days (IQR: 26-64). The delay until diagnostic confirmation was 15.8 ± 4.8 days. Conclusions. All patients were diagnosed using the bioassay technique, which resulted in a diagnostic delay that exceeds the recommended period for the administration of a specific treatment. No patient received a specific treatment. IB was related to a low mortality, but also to prolonged use o  MV and length of hospital stay, which were associated with cross infections and frequent antibiotic use.

Introducción. El botulismo del lactante (BL) es la forma más frecuente de botulismo humano en Argentina. El objetivo es describir aspectos esenciales del diagnóstico y tratamiento de pacientes con BL internados en el servicio de terapia intensiva pediátrica (STIP). Métodos. Estudio observacional, descriptivo y retrospectivo. Se utilizó la base de datos del STIP con diagnóstico de BL en el período 2005-2020. Se registraron variables demográficas, métodos de diagnóstico, días de asistencia respiratoria mecánica convencional (ARMC), de ventilación no invasiva (VNI), estadía en STIP, mortalidad al alta hospitalaria. Resultados. Se registraron 21 pacientes con BL; 14 pacientes fueron varones, con una mediana de edad de 5 meses (RIC 2-6 m). El diagnóstico se realizó mediante técnica de bioensayo y se detectó la toxina en suero en 12 pacientes. Uno solo no requirió ARMC; 1 paciente fue traqueostomizado; 18 pacientes recibieron antibióticos; 5 recibieron VNI. Ningún paciente recibió antitoxina y no hubo fallecidos. La mediana de estadía hospitalaria fue 66 días (RI: 42-76); de internación en STIP, 48 días (RI: 29-78); y de ARMC, 37 días (RI: 26-64). La demora en la confirmación diagnóstica fue 15,8 ± 4,8 días. Conclusiones. La totalidad de los pacientes fueron diagnosticados con la técnica de bioensayo, que generó un tiempo de demora diagnóstica que excede los lapsos recomendados para la administración del tratamiento específico. Ningún paciente recibió tratamiento específico. El BL presentó baja mortalidad, pero tiempos de ARM e internación prolongados, que se asocian a infecciones sobreagregadas y uso frecuente de antibióticos.

Encuesta sobre usos y prácticas de Doppler transcraneal en pacientes neurocríticos en unidades de cuidados intensivos pediátricos de Argentina / Survey on the use and practice of transcranial Doppler ultrasound in neurocritical patients in pediatric intensive care Units in Argentina

Introducción. El uso del Doppler transcraneal (DTC) en pacientes neurocríticos se reporta cada vez más en las terapias intensivas pediátricas. El objetivo de esta encuesta es conocer los usos y prácticas del DTC en la atención neurocrítica y el proceso de formación del personal que realiza el estudio. Materiales y métodos. Encuesta a profesionales de 23 unidades de terapia intensiva pediátrica de Argentina. Resultados. Porcentaje de respuesta del 86 %. Se utilizó en sospecha de muerte encefálica (n = 20), trauma de cráneo (n = 16) y accidente cerebrovascular (n = 16). El intensivista pediátrico es quien realiza los estudios (n = 13/20). Los encuestados utilizan el Doppler para decidir conductas y tratamientos, comenzar el proceso de evaluación de muerte encefálica, solicitar tomografía de cerebro y manejar la presión de perfusión cerebral con vasopresores. Conclusión. Todos los encuestados utilizan los hallazgos del DTC para guiar tratamientos o conductas. La mitad de los encuestados está poco conforme con la capacitación recibida.

Introduction. The use of transcranial Doppler (TCD) ultrasoundin neurocritical patients is reported to be increasingly common in pediatric intensive care units. The objective of this survey was to know about the use and practice of TCD ultrasound in neurocritical care and the training process of staff members performing it. Materials and methods. Survey administered to providers from 23 pediatric intensive care units of Argentina. Results. The percentage of response was 86%. TCD ultrasound was used for suspected brain death (n = 20), head injury (n = 16), and stroke (n = 16). Pediatric intensivists perform the test (n = 13/20). Surveyed participants use TCD ultrasound to decide on treatment and management, start brain death assessment, request brain computed tomography, and manage cerebral perfusion pressure with vasopressors. Conclusion. All surveyed participants use TCD ultrasound findings to guide management or treatments. Half of surveyed participants are little satisfied with their training.

Survey on the use and practice of transcranial Doppler ultrasound in neurocritical patients in pediatric intensive care Units in Argentina. / Encuesta sobre usos y prácticas de Doppler transcraneal en pacientes neurocríticos en unidades de cuidados intensivos pediátricos de Argentina.

INTRODUCTION: The use of transcranial Doppler (TCD) ultrasound in neurocritical patients is reported to be increasingly common in pediatric intensive care units. The objective of this survey was to know about the use and practice of TCD ultrasound in neurocritical care and the training process of staff members performing it. MATERIAL AND METHODS: Survey administered to providers from 23 pediatric intensive care units of Argentina. RESULTS: The percentage of response was 86%. TCD ultrasound was used for suspected brain death (n = 20), head injury (n = 16), and stroke (n = 16). Pediatric intensivists perform the test (n = 13/20). Surveyed participants use TCD ultrasound to decide on treatment and management, start brain death assessment, request brain computed tomography, and manage cerebral perfusion pressure with vasopressors. CONCLUSIONS: All surveyed participants use TCD ultrasound findings to guide management or treatments. Half of surveyed participants are little satisfied with their training.

Introducción. El uso del Doppler transcraneal (DTC) en pacientes neurocríticos se reporta cada vez más en las terapias intensivas pediátricas. El objetivo de esta encuesta es conocer los usos y prácticas del DTC en la atención neurocrítica y el proceso de formación del personal que realiza el estudio. Materiales y métodos. Encuesta a profesionales de 23 unidades de terapia intensiva pediátrica de Argentina. Resultados. Porcentaje de respuesta del 86 %. Se utilizó en sospecha de muerte encefálica (n = 20), trauma de cráneo (n = 16) y accidente cerebrovascular (n = 16). El intensivista pediátrico es quien realiza los estudios (n = 13/20). Los encuestados utilizan el Doppler para decidir conductas y tratamientos, comenzar el proceso de evaluación de muerte encefálica, solicitar tomografía de cerebro y manejar la presión de perfusión cerebral con vasopresores. Conclusión. Todos los encuestados utilizan los hallazgos del DTC para guiar tratamientos o conductas. La mitad de los encuestados está poco conforme con la capacitación recibida.

Optimization of five environmental factors to increase beta-propeller phytase production in Pichia pastoris and impact on the physiological response of the host.

Recently, we engineered Pichia pastoris Mut(s) strains to produce several beta-propeller phytases, one from Bacillus subtilis and the others designed by a structure-guided consensus approach. Furthermore, we demonstrated the ability of P. pastoris to produce and secrete these phytases in an active form in shake-flask cultures. In the present work, we used a design of experiments strategy (Simplex optimization method) to optimize five environmental factors that define the culture conditions in the induction step to increase beta-propeller phytase production in P. pastoris bioreactor cultures. With the optimization process, up to 347,682 U (82,814 U/L or 6.4 g/L culture medium) of phytase at 68 h of induction was achieved. In addition, the impact of the optimization process on the physiological response of the host was evaluated. The results indicate that the increase in extracellular phytase production through the optimization process was correlated with an increase in metabolic activity of P. pastoris, shown by an increase in oxygen demand and methanol consumption, that increase the specific growth rate. The increase in extracellular phytase production also occurred with a decrease in extracellular protease activity. Moreover, the optimized culture conditions increased the recombinant protein secretion by up to 88%, along with the extracellular phytase production efficiency per cell.

Shrimp (Litopenaeus vannamei) trypsinogen production in Pichia pastoris bioreactor cultures.

Recently, we engineered a Pichia pastoris Mut(+) strain to produce and secrete recombinant Litopenaeus vannamei trypsinogen. Despite the observed toxicity of the recombinant shrimp trypsinogen to the P. pastoris cell host, when high density cell cultures in shake flasks with alanine in the induction medium were used recombinant shrimp trypsinogen could be produced. To further improve the product yield, in this work, we evaluated L. vannamei trypsinogen production in P. pastoris using a bioreactor and two recombinant P. pastoris strains with different methanol utilization (Mut) phenotypes. The effect of pH and temperature during the induction step on the trypsinogen production was also evaluated. The results indicate that temperature, pH, and Mut phenotypes influence the production of the recombinant protein, with almost no observed effect on cell growth. All cultures with the Mut(+) strain had significant operational difficulties, such as in lowering the induction temperature, maintaining dissolved oxygen (DO) above 20%, and maintaining the methanol concentration at a constant value, and showed a decrease in metabolic activity due to trypsinogen toxicity to the cell host. In the culture with the Mut(s) strain, however, the temperature, methanol concentration, and DO could be more easily controlled, the temperature could be easily decreased, and the trypsinogen caused the lowest toxicity to the host cells. After 96 h of Mut(s) strain induction (pH 6 and 25°C), about 250 mg/L recombinant trypsinogen was detected in the culture medium.