Serotype distribution, clinical characteristics, and antimicrobial resistance of pediatric invasive pneumococcal disease in Colombia during PCV10 mass vaccination (2017-2022).

Introduction: Invasive Pneumococcal Disease (IPD) causes significant morbidity and mortality in children under 5 y. Colombia introduced PCV10 vaccination in 2012, and the Neumocolombia network has been monitoring IPD in pediatric patients since 2008. Materials and methods: This study is a secondary analysis of a prospective cohort involving pediatric patients with IPD admitted to 17 hospitals in Colombia, from January 1st, 2017, to December 31st, 2022. We present data on serotypes (Spn), clinical characteristics, and resistance patterns. Results: We report 530 patients, 215 (40.5%) were younger than 24 months. Among these, 344 cases (64.7%) presented with pneumonia, 95 (17.9%) with primary bacteremia, 53 (10%) with meningitis, 6 (1.1%) had pneumonia and meningitis, and 32 (6%) had other IPD diagnosis. The median hospital stay was 12 days (RIQ 8-14 days), and 268 (50.6%) were admitted to the ICU, of whom 60 (11.3%) died. Serotyping was performed in 298 (56.1%). The most frequent serotypes were Spn19A (51.3%), Spn6C (7.7%), Spn3 (6.7%), Spn6A (3.6%), and Spn14 (3.6%). Of 495 (93%) isolates with known susceptibility, 46 (9.2%) were meningeal (M) and 449 (90.7%) non-meningeal (NM). Among M isolates, 41.3% showed resistance to penicillin, and 21.7% decreased susceptibility to ceftriaxone. For NM isolates, 28.2% had decreased susceptibility to penicilin, and 24.2% decreased susceptibility to ceftriaxone. Spn19A showed the highest resistant to penicillin at 47% and was linked to multiresistance. Conclusion: The prevalence of PCV10-included serotypes decreased, while serotypes 19A and 6C increased, with Spn19A being associated with multiresistance. These findings had played a crucial role in the decision made by Colombia to modify its immunization schedule by switching to PCV13 in July 2022.

Changes in the incidence of acute bacterial meningitis caused by Streptococcus pneumoniae and the implications of serotype replacement in children in Colombia after mass vaccination with PCV10.

Introduction: Acute bacterial meningitis (ABM) is a public health problem. The disease has reemerged after the introduction of pneumococcal conjugate vaccines (PCVs) due to an increase in serotypes that are not covered. The objective was to determine the changes in the disease incidence before and after the introduction of the 10-valent vaccine (PCV10) in Colombia. Methods: This multicenter study was conducted in 17 hospitals in Colombia. Data were collected from January 2008 to December 2019 in 10 hospitals in Bogotá and from January 2017 to December 2019 in seven hospitals in Cali, Medellín and Cartagena. The data were grouped into three periods: 2008-2011, 2012-2015, and 2016-2019. Results: Of the 706 cases of invasive pneumococcal disease, 81 (11.4%) corresponded to meningitis. The relative incidence in Bogotá in the first period was 0.6 per 100,000 patients ≤ 5 years, decreased to 0.4 per 100,000 patients ≤ 5 years in the second period and increased in the third period to 0.7 per 100,000 patients ≤ 5 years. Serotypes covered by PCV10 decreased from 75 to 9.1%, with Spn19A (31.8%) and Spn34 (13.6%) emerging in the third period. Increased resistance to penicillin (13 to 37%) and to ceftriaxone (5.9 to 16%) was due to the emergence of multidrug-resistant Spn19A. The total mortality rate was 23.5% and increased from 12 to 33%. Conclusions: ABM due to pneumococcus has high morbidity and mortality rates. Reemergence of the disease has been observed due to the inclusion of polymerase chain reaction (PCR) for diagnosis and replacement of circulating serotypes after the introduction of PCV10, with an increase in Spn19A, which causes death and exhibits antimicrobial resistance. Continued surveillance is needed.

Epidemiological characteristics and serotype distribution of culture-confirmed pediatric pneumococcal pneumonia before and after PCV 10 introduction, a multicenter study in Bogota, Colombia, 2008-2019.

BACKGROUND: Pneumococcal conjugate vaccines (PCVs) have decreased pneumonia in children. Colombia introduced mass vaccination with PCV10 in 2012. METHODS: Cases of pneumococcal pneumonia from 10 hospitals were included. Two periods were compared: pre-PCV10: 2008-2011 and post-PCV10: 2014-2019. The objective was to compare epidemiological and clinical characteristics before and after PCV10 vaccination. RESULTS: A total of 370 cases were included. Serotypes 1 (15, 11.2%) and 14 (33, 24.6%) were the most frequent in the pre-PCV10 period, with only 4 (3%) cases of serotype 19A and 1 case (0.7%) serotype 3. From the pre-PCV10 period to the post-PCV10 period, cases of serotypes 1 (6, 3.1%) and 14 (1, 7.8%) decreased, while cases of serotypes 19A (58, 30.2%), serotype 3 (32, 16.7%) and 6A (7, 3.6%) increased (p < 0.001); complicated pneumonia (CP) increased significantly (13.4% to 31.8%) (p < 0.001); hospitalizations increased from 8 (5.5-15) to 12 (7-22) days (p < 0.001); and the frequency of PICU admission increased from 32.8% to 51.6% (p = 0.001). The use of ampicillin-sulbactam (0.7% to 24%) and ceftriaxone/clindamycin (0.7% to 5.7%) increased in the post-PCV10 period. The duration of empirical antibiotic treatment was 7 (4-11) days in the pre-PCV10 period and increased to 10 (6-17) days (p < 0.001) in the post-PCV10 period. Lethality showed a slight nonsignificant increase (7.5% vs. 9.9%; p = 0.57) in the post-PCV10 period. CONCLUSIONS: PCV10 significantly decreased cases of serotypes 1 and 14, with an increase in cases of serotypes 19A, 3 and 6A, which were the predominant serotypes and had greater severity (e.g., admission to the PICU, CP and more resistance, with an increase in the use of broad-spectrum antibiotics and longer hospitalization) and subsequently included in PCV13. Current data support national and regional evidence on the importance of replacing PCV10 with a higher valence that includes 19A, such as PCV13, with the aim of reducing circulation, particularly of this serotype.

Risk Factors for Mortality in Colombian Patients with Candidemia.

The aim of the study was to describe the microbiology and susceptibility profile of candidemia and to identify the risk factors associated with mortality in Colombia. A cohort of patients was followed for 30 days during 2008 to 2010. Microbiological identification and susceptibility assessments were performed in a reference centre. Demographic, clinical and treatment variables were evaluated for their associations with mortality. A parametric survival regression analysis was used to identify the risk factors associated with mortality. A total of 109 patients with candidemia in four hospitals in Colombia were identified, with a median age of 30 years old. C. parapsilosis was the most frequently identified microorganism (38.5%); the susceptibility of all isolates was high to fluconazole and anidulafungin, except for C. glabrata isolates. The overall mortality was 35.7%, and the risk factors associated with mortality included lack of antifungal treatment (HR 5.5, 95% CI 3.6-11.4), cancer (HR 3.9, 95% CI 2.3-8.0), diabetes (HR 2.5, 95% CI 1.03-6.4), and age (HR 1.13 per every 10 years, 95% CI 1.02-1.24). Catheter removal was associated with a low mortality rate (HR 0.06, 95% CI 0.00-0.49). Prompt antifungal treatment, better glycemic control and catheter removal should be prioritized in the management of candidemia.

Emergence of Streptococcus pneumoniae serotype 19A (Spn19A) in the pediatric population in Bogotá, Colombia as the main cause of invasive pneumococcal disease after the introduction of PCV10.

Introduction: With the use of pneumococcal conjugate vaccines(PCV), the behavior of invasive pneumococcal disease(IPD) has changed relative to serotype distribution. The introduction of these vaccines in national immunization programs has reduced the incidence of IPD, with a marked decrease in the circulation of the serotypes included in the vaccine used in each country. However, the subsequent emergence of other serotypes not included in the vaccine, such 19A in case of PCV7 and PCV10, has been documented. Materials and methods: This was case series study (2008-2017) in pediatric patients admitted to 10 hospitals in Bogota who were diagnosed with IPD. It was conducted during the transitional period of implementing the PCV10 vaccine in Colombia in 2012. Cases of bacteremic pneumococcal pneumonia, meningitis, primary bacteremia and osteoarticular infection were included. A descriptive analysis of the demographic, clinical and laboratory variables of patients with IPD by Spn19A, its trend over time, profiles of antimicrobial susceptibility and clinical outcomes was performed. Results: There were 463 cases of IPD, 315(68%) with known serotypes. The prevalence of IPD by Spn19A was 17.7%(56 cases), tending to increase over time. During 2008-2011, the prevalence was 4.4%, and during 2014-2017, it was 32.4%, The most frequent diagnosis was pneumonia(80.4%). In nonmeningeal isolates, 39.6% were not susceptible to penicillin. An increase in the resistance was observed over time. Conclusion: Spn19A is a prevalent cause of IPD in the pediatric population of the analyzed cohort, with an increasing trend of this serotype during the surveillance period after the introduction of PCV10, being the most common serotype identified in recent years.

First case of Aspergillus caelatus airway colonization in a Chronic Obstructive Pulmonary Disease patient.

BACKGROUND: During a cross-sectional study on allergic aspergillosis in Chronic Obstructive Pulmonary Disease patients in Bogotá, Colombia, we reported the case of a 65-year-female patient with GOLD 2011 D classification, presenting dyspnea at the time of visit and aspergillus in repeated sputum cultures. METHODS: The isolate was identified at the section level based on macroscopic and microscopic characteristics and gene sequencing was used for precise molecular identification. Antifungal sensibility was determined by Sensititre YeastOne™ while virulence was assessed using a Galleria mellonella larvae model. RESULTS: The clinical isolate was first identified as Aspergillus section Flavi and sequencing of ß-tubulin and calmodulin genes, in addition to the identification of alfR (aflatoxin regulator) gene, allowed the undoubted identification of the clinical isolate as Aspergillus caelatus. It exhibited virulence in G. mellonella similar to A. flavus and a high in vitro susceptibility against all antifungals except for amphotericin B. CONCLUSION: This is the first human case of airway colonization attributed to A. caelatus. Resistance pattern justified the interest to discriminate this cryptic species.

Caracterización de pacientes fallecidos por enfermedad neumocóccica invasiva en la poblacion infantil de Bogotá, Colombia / Characterization of patients who died of invasive pneumococcal disease in the child population of Bogota, Colombia

Introducción: El Streptococcus pneumoniae (S. pneumoniae), también denominado neumococo, es una de las principales bacterias asociadas a mortalidad en menores de 2 años, con una incidencia de morbimortalidad variable de acuerdo a la demografía y exposición a factores protectores o de riesgo. Objetivo: Caracterizar los pacientes fallecidos por enfermedad neumocóccica invasiva (ENI) entre el 2008-2014 en la población infantil de 8 instituciones de salud en Bogotá, Colombia. Pacientes y método: Estudio observacional descriptivo tipo serie de casos, en pacientes fallecidos por ENI, mayores de 28 días hasta los 18 años, en 8 instituciones de tercer nivel de atención en Bogotá, Colombia. Periodo del estudio del 1 de enero de 2008 al 15 de enero de 2014. Tamaño de la muestra: 239 pacientes. Resultados: Se revisaron 239 casos registrados de ENI, presentando una mortalidad del 7,5% (n = 18). La edad promedio de los pacientes que fallecieron fue de 43,7 meses, con un rango de edad entre 2 y 176 meses (14 años); el 66% de los casos era de sexo masculino. Se identificaron serotipos en 8 pacientes, encontrando: 6A, 6B, 10A, 14, 18C, 23B, 23F, 35B. La presentación clínica más frecuente de los casos de mortalidad fue meningitis con el 33% (6 casos), seguida por bacteriemia sin foco en el 28% (5 casos) y neumonía con el 27% (5 casos). Se presentaron situaciones clínicas combinadas como neumonía y meningitis en el 11% (2 casos). Dos de los pacientes tenían factores de riesgo para ENI claramente documentados (asplenia y enfermedad respiratoria crónica). Conclusiones: La mortalidad por ENI es especialmente alta en los menores de 2 años y en pacientes de sexo masculino, especialmente cuando presenta foco meníngeo (44%). La serotipificación no fue posible en todos los pacientes fallecidos, ya que no se envió la cepa aislada al Instituto Nacional de Salud. Se requiere una vigilancia continua y sistemática para evaluar el impacto de la vacunación y las posibles modificaciones en el patrón de presentación de la enfermedad.

Introduction: Streptococcus pneumoniae (S. pneumoniae), also known as pneumococcus, is one of the main bacteria associated with mortality in children under 2 years of age, with a morbidity and mortality incidence that varies according to demographics and exposure to risk, or protective factors. Objective: To describe the child mortality due to invasive pneumococcal disease (IPD) between 2008 -2014 (6 years), in 8 Medical Centres in Bogotá, Colombia. Patients and method: Descriptive observational case series of patients who died of IPD, aged 28 days to 18 years, in 8 tertiary care institutions in Bogota, Colombia. The study period was from 1 January 2008 to 15 January 2014. Sample size: 239 patients. Results: A total of 239 registered cases of IPD were reviewed, showing a mortality of 8% (n 18). The mean age of patients that died was 43.7 months, with an age range from 2 to 176 months (14 years), with 66% of the cases being male. Serotypes were identified in 8 patients, finding: 6A, 6B, 10A, 14, 18C, 23B, 23F, and 35B. The most common clinical presentation of the cases was meningitis with mortality of 33% (6 cases), followed by bacteraemia without focus in 28% (5 cases), and pneumonia with 27% (5 cases). Combined clinical situations were presented, such as pneumonia and meningitis in 11% (2 cases). Two of the patients had clearly documented risk factors for IPD (asplenia and chronic respiratory disease). Conclusions: IPD mortality is particularly high in children under 2 years in male patients, especially when presented with a meningeal focus (44%). Serotyping was not possible in all patients who died, since no strain isolated was sent to the National Institute of Health. Continuous and systematic vigilance is required to evaluate the impact of vaccination and possible changes in the pattern of presentation of disease.

[Characterization of patients who died of invasive pneumococcal disease in the child population of Bogota, Colombia]. / Caracterización de pacientes fallecidos por enfermedad neumocóccica invasiva en la poblacion infantil de Bogotá, Colombia.

INTRODUCTION: Streptococcus pneumoniae (S. pneumoniae), also known as pneumococcus, is one of the main bacteria associated with mortality in children under 2 years of age, with a morbidity and mortality incidence that varies according to demographics and exposure to risk, or protective factors. OBJECTIVE: To describe the child mortality due to invasive pneumococcal disease (IPD) between 2008 -2014 (6 years), in 8 Medical Centres in Bogotá, Colombia. PATIENTS AND METHOD: Descriptive observational case series of patients who died of IPD, aged 28 days to 18 years, in 8 tertiary care institutions in Bogota, Colombia. The study period was from 1 January 2008 to 15 January 2014. SAMPLE SIZE: 239 patients. RESULTS: A total of 239 registered cases of IPD were reviewed, showing a mortality of 8% (n 18). The mean age of patients that died was 43.7 months, with an age range from 2 to 176 months (14 years), with 66% of the cases being male. Serotypes were identified in 8 patients, finding: 6A, 6B, 10A, 14, 18C, 23B, 23F, and 35B. The most common clinical presentation of the cases was meningitis with mortality of 33% (6 cases), followed by bacteraemia without focus in 28% (5 cases), and pneumonia with 27% (5 cases). Combined clinical situations were presented, such as pneumonia and meningitis in 11% (2 cases). Two of the patients had clearly documented risk factors for IPD (asplenia and chronic respiratory disease). CONCLUSIONS: IPD mortality is particularly high in children under 2 years in male patients, especially when presented with a meningeal focus (44%). Serotyping was not possible in all patients who died, since no strain isolated was sent to the National Institute of Health. Continuous and systematic vigilance is required to evaluate the impact of vaccination and possible changes in the pattern of presentation of disease.

Frequency of microorganisms isolated in patients with bacteremia in intensive care units in Colombia and their resistance profiles

OBJECTIVE: The aim of this study was to describe the most frequently found bacterial microorganisms in bloodstream isolates taken from patients in intensive care units in Colombia and their resistance profiles. METHODS: This was a multicentre descriptive observational study that was carried out between January 2001 and June 2008 with laboratory data from 33 participating hospitals in a surveillance network. RESULTS: The most frequently found microorganisms were coagulase-negative Staphylococci 39.6%, Staphylococcus aureus 12.3%, Klebsiella pneumoniae 8.2%, Escherichia coli 5.7%, Acinetobacter baumannii, 4.0% and Pseudomonas aeruginosa 3.8%. Coagulase-negative Staphylococci registered greater than 70% oxacillin resistance rate. S. aureus presented a change in its multiresistance profile during the years of follow-up. There was a trend towards a lower resistance rate among E. coli and K. pneumoniae isolates during the study period while A. baumannii carbapenem resistance rate exceeded 50%. DISCUSSION: There has been a change in the frequency of species being isolated with a higher frequency of enterobacteriaceae compared to Gram-positive microorganisms, in general with a high resistance rate.

Frequency of microorganisms isolated in patients with bacteremia in intensive care units in Colombia and their resistance profiles.

OBJECTIVE: The aim of this study was to describe the most frequently found bacterial microorganisms in bloodstream isolates taken from patients in intensive care units in Colombia and their resistance profiles. METHODS: This was a multicentre descriptive observational study that was carried out between January 2001 and June 2008 with laboratory data from 33 participating hospitals in a surveillance network. RESULTS: The most frequently found microorganisms were coagulase-negative Staphylococci 39.6%, Staphylococcus aureus 12.3%, Klebsiella pneumoniae 8.2%, Escherichia coli 5.7%, Acinetobacter baumannii, 4.0% and Pseudomonas aeruginosa 3.8%. Coagulase-negative Staphylococci registered greater than 70% oxacillin resistance rate. S. aureus presented a change in its multiresistance profile during the years of follow-up. There was a trend towards a lower resistance rate among E. coli and K. pneumoniae isolates during the study period while A. baumannii carbapenem resistance rate exceeded 50%. DISCUSSION: There has been a change in the frequency of species being isolated with a higher frequency of enterobacteriaceae compared to Gram-positive microorganisms, in general with a high resistance rate.