Abdominal tuberculosis in pediatrics: A case report

Tuberculosis is an infectious disease which most commonly compromises the respiratory system, whereas abdominal involvement is rare, thus its diagnosis is a challenge. The clinical manifestations of abdominal tuberculosis as well as its physical examination findings are usually non-specific and, frequently, similar to those of other diseases, so it is critical to consider abdominal tuberculosis among the differential diagnoses. Here we report the clinical case of a 15-year-old male patient hospitalized for a prolonged febrile syndrome associated with abdominal pain, diarrhea, night sweats, and weight loss.

Meningococcal burden of disease in Argentina: 10 years epidemiologic review

Invasive meningococcal disease (IMD) is an uncommon but serious and potentially fatal condition, mainly affecting infants. In 2017, Argentina introduced a vaccination program against serogroups A, C, W and Y (MenACWY) for infants aged 3, 5 and 15 months and adolescents aged 11 years. The objective of this study was to review the burden of IMD in Argentina in 2010-2019. Data were obtained from national surveillance databases, and the study estimated IMD incidence, mortality, case-fatality rates, and serogroup distributions across age groups. A total of 1,972 IMD cases were reported in the study period, with the highest incidence in infants aged < 1 year. Incidence peaked in 2013 and subsequently declined. Mortality rates were 18 times higher in infants than in other age groups, reflecting the high impact of IMD in this age group. The case-fatality rate was 8.5% on average and increased with age. The proportion of notified cases with serogroup identification increased over the period, reaching 91% in 2019. The most common serogroups over the study period were serogroup B (48%) and serogroup W (42%), with an increase in B relative to W since 2015. In infants aged < 1 year, the proportion of serogroup B increased in recent years, reaching around 70% of characterized cases in 2018-2019. These results show the dynamism of IMD and indicate the importance of vaccination at an early age and offering protection against predominant serogroups. These data are valuable to support evidence-based decision-making in healthcare.

2047. Meningococcal burden of disease in Argentina: 10 years epidemiologic review

Background

Reduction of Invasive meningococcal disease (IMD) burden is one of the public health main priorities in Argentina. Since 2017, MenACWY vaccination was implemented for infants (3-5 and 15 months) and adolescents (11 years). However, epidemiological studies have been scarce in recent years. Considering the changing dynamic of the disease, specially related to serogroups circulation, we decided to carry out an epidemiological review and update IMD information that contributes to assess the best prevention strategy.

Methods

Retrospective 2010-2019 observational and descriptive study, based on Argentina Ministry of Health secondary data. Main outcomes included IMD incidence rates, serogroups distribution, mortality and case fatality ratios (CFR) stratified by year, age groups, (infants: 0-11 months; 1 to 4 y; 5 to 19 y; &gt;20 to 29 y; &gt;30 to 39 y; 40 to 49 y; 50 to 59 y; &gt;60 y) and regions.

Results

1,972 IMD cases were notified in the study period. Incidence reached its maximum in 2013 (0.69/100,000) and steadily declined to 0.22-0.23/100,000 in 2018-2019. Highest incidence rates were observed in infants (exceeding 14/100,000 in 2012, with no adolescent’s peak) and in the center of the country (reaching a value of 0.9/100,000 in 2013). There were 167 meningococcal deaths during 2010-2019 with a downtrend since 2014. Mortality rates were 18 times higher in infants versus all other age groups. CFR for the entire period was 8.5% and increased with age (&lt; 7% in &lt; 20y to 26% in &gt;60y). Serogroup identification from notified cases increased from 73% in 2010 to 91% in 2019. From all characterized strains 47% and 42% corresponded to serogroup B and W, respectively. A higher predominance of serogroup B over W was observed during the last 5 years, especially in infants and in the central region.

Conclusion

The highest burden of meningococcal disease focused on children &lt; 1yoa with a growing predominance of serogroup B. This trend highlights the importance of vaccination at very early age adding protection against serogroup B in this age group. These results will contribute to the process of evidence-based decision making.

Disclosures

Analia urueña, n/a, MSD: Grant/Research Support|Received funding for investigator led studies from GSK,: Advisor/Consultant|Received funding for investigator led studies from GSK,: Grant/Research Support|Received funding for investigator led studies from GSK,: Honoraria|Sanofi: Grant/Research Support|Seqirus: Advisor/Consultant|Seqirus: Grant/Research Support|Takeda: Grant/Research Support Maria Eugenia Pannunzio, n/a, GSK Argentina: Employee María Seoane, n/a, GSK: Board Member|GSK: Stocks/Bonds Jorge Gómez, n/a, GlaxoSmithKline: Employee|GlaxoSmithKline: Stocks/Bonds Norberto Giglio, GSK: Grant/Research Support|GSK: Honoraria|Received funding for investigator led studies from GSK,: Grant/Research Support|Received funding for investigator led studies from GSK,: Honoraria|SANOFI: Grant/Research Support|SANOFI: Honoraria|Sequirus: Grant/Research Support|Sequirus: Honoraria.

Laboratory surveillance of invasive Haemophilus influenzae disease in Argentina, 2011-2019

The incorporation of Haemophilus influenzae type b (Hib) vaccine into the Argentine National Immunization Program in 1998 resulted in a dramatic decrease in the incidence of invasive disease due to this serotype. We assessed 1405 H. influenzae (Hi) isolates causing invasive infections referred to the National Reference Laboratory between 2011 and 2019. Non-encapsulated Hi were the most common strains (44.5%), followed by types b (41.1%) and a (10.0%). Significant increase in the proportion of type b was observed, from 31.2% in 2011, to 50% in 2015, correlating with the peak incidence rate, later decreasing to 33.6% by 2019. We compared the genetic relationship between clones circulating during the period of increased Hib incidence (2011-2015) and those of the prevaccination-transition period (1997-1998). Four pulsotypes predominated in both periods, G, M, P and K, G being the most common. Multi-locus sequence typing revealed that the 4 pulsotypes belonged to ST6, or one of its simple or double locus variants. Isolates from fully vaccinated individuals did not differ from those of the rest of the population studied. After ruling out aspects associated with emergence of specific clones, we concluded that factors such as low booster coverage rates, delayed vaccination schedules and use of different vaccines may have contributed to the reemergence of Hib infections.

1382. Varicella Burden Disease in Argentina: 4 Years after National Vaccination Strategy

Background

In Argentina, around 150,000-180,000 total Varicella (VZV) cases per year (c/y) are registered; however, underreport exists and some 400,000 cases are estimated to occur annually. Varicella vaccine (VV) was included in the National Immunization Schedule (NIS) in 2015, with a 1-dose schedule administered at 15 months-of-age. We aimed to describe and to compare the epidemiological situation of VZV infections in Argentina in two periods: pre (2010-2014) and post (2016-2018) vaccine introduction in NIS.

Global Incidence rates and vaccine coverages

Incidence rates (age groups)

Methods

Before-and-after study comparing cases and incidence rates (100,000) of varicella reported to the National Health Surveillance System between pre-vaccination period (Pre-VV) and post-vaccination (Post-VV), excluding year of intervention (2015) since it was considered a transition year. Epi Info 7 was used for data analysis.

Results

Vaccination coverage (VC) for 2015 was 44.7%; 74.4% in 2016; 76.8% in 2017 and 81% in 2018 (Figure 1). 728,392 cases of VZV were notified (R=363.1) in Pre-VV period and 222,305 cases in Post-VV (R=180.7), with a global incidence rate reduction of 49% (95%CI= 40.9-56.2; p< 0.001). Both 12-24 months of age and 2-4 years old groups (Pre-VV R=2,253 and Post-VV R=900; Pre-VV R=2,399 and Post-VV R=875, respectively) showed the greatest reductions in incidence rates (-59.3% [95%CI 58.7-60] p< 0.001 and -61.7% [95%CI 61.3-62] p< 0.001). Age groups not affected by vaccination (< 1 year, 5-9 years and 10-14 years) presented minor but significant reductions (-56.4% [95%CI 55.6-57.3] p< 0.001; -35% [95%CI 34.5-35.4] p< 0.001; and -28.6% [95%IC 27.6-29.7] p< 0.001 respectively) (Figure 2).

Conclusion

A decreasing trend in VZV number of cases and incidence rates was observed, especially in children less than 5 years old, despite suboptimal VC. The reduction of VZV cases in non-vaccinated age groups could be related to a decline in the transmission risk. Improving VC will likely reflect a greater impact on the burden of disease.

Disclosures

All Authors: No reported disclosures

2326. Enterovirus-Associated Acute Flaccid Myelitis. Argentina′s Nationwide Surveillance of Acute Flaccid Paralysis 2016–2018

Background

Acute flaccid paralysis (AFP) surveillance is carried out in Argentina in the frame of the Polio Eradication Program. Acute flaccid myelitis (AFM) is a type of AFP and can be detected in the frame of AFP surveillance. Although many case series of AFM associated to enterovirus (EV) were released since 2014 in many countries, there were no notifications of this entity from Argentina until 2016.

Methods

Descriptive-observational study. AFP cases reported to the National Surveillance System (NSS) between 2016 and 2018 were included.

Results

From January 1, 2016 to December 31, 2018, 610 cases of AFP in children under 15 years old were registered (207 in 2016, 205 in 2017 and 198 in 2018). In 2016, from epidemiological weeks (EWs) 14 to 28, 23 cases of AFM were notified (median age 36 months; range: 3 months to 13 years). No special clustering was observed, and the number of AFM cases did not correlate with an increase in the annual rate of AFP notifications. Main prodromal were respiratory symptoms in 21 cases (91.3%) and fever in 18 (78.2%). One or two limbs were affected in 65%; in 35% mechanical ventilation was required. More than 90% had sequelae at discharge. Stool (ST), nasopharyngeal aspirate (NPA) and cerebrospinal fluid (CSF) samples were processed at the Regional Reference Laboratory facilities. RT nested PCR was employed. All detections are shown in Table 1. To note, In 12 cases (53%), EV D68 was detected (11, out of 16 NPA and 3, out of 11 ST samples). As for 2017, only one case of AFM was detected. Attempt of viral detection was unsuccessful. In 2018, 3 cases of AFM were detected, one EV C105, one Coxsackie B and one case without viral detection.

Conclusion

The occurrence of AFM cases in Argentina since 2016 is similar to the findings in other countries. An association with EV D68 is apparent, notwithstanding the finding of other EV, finding that further points to the causal association between EV D68 and AFM. As NPA is the sample of choice for AFM diagnosis, from 2019 the work-out of every case of AFP includes this sample as mandatory when AFM is suspected. Given the severity and the high rate of permanent sequelae, a high sensitivity of the health team must be sustained to keep with adequate surveillance, which allows prompt outbreak detection of other agents that can cause AFP in the last phase of polio eradication.

Disclosures

All authors: No reported disclosures.

[Atypical presentation of Spondylodiscitis by Kingella Kingae: a case report]

Infectious Spondylodiscitis is a rare infection in children. It is more frequent in patients under 6 years of age. We report the case of an 8-year-old patient with lumbar pain for 2 months, without fever. Xrays, computed tomography and magnetic resonance imaging all three showed spondylodiscitis L4-L5. After a 10-day antibiotic treatment with clindamycin with regular response, a bone puncture was performed isolating Kingella kingae (Kk). Ostearticular infections caused by Kk have increased among infants and children. Due to improvement in culture techniques, the usage of automatic systems and assessment molecular techniques, these infections re-emerged in the past few years. Kk is a pathogen that has lately become significant in osteoarticular infections.

2476. Impact of the Vaccination Strategy on Varicella Burden Disease in Argentina

Background

Varicella (VZV) is one of the most frequent exanthematic diseases in childhood. In Argentina, around 150,000–180,000 total cases per year are registered; however, underreport exists and some 400,000 cases are estimated to occur annually. Varicella vaccine (VV) was included in the national immunization schedule (NIS) in 2015, with a 1-dose schedule administered at 15 months of age. The information provided by epidemiological surveillance is essential to evaluate the impact of public health decisions. Our objective was to describe and to compare the epidemiological situation of VZV infections in Argentina in two periods: pre (2010–2014) and post (2016–2017) vaccine introduction in NIS.

Methods

Descriptive study. We compared cases and incidence rates (R) of VZV per 100,000 population (global and disaggregated by age) reported to the National Health Surveillance System; in pre (Pre-VV) and post-vaccination (Post-VV) periods. Data analysis of 2015 was excluded since it was considered a transition year.

Results

Vaccination coverage for 2015 was 44.7%; 74.4% in 2016 and 75.5% in 2017. 728,392 cases of VZV were notified (R = 362,1) in Pre-VV period and 176,995 cases in Post-VV (R = 220.6), with a global incidence rate reduction of 39% (IC 95% =38.9–39.6; P < 0.001). Both 12–24 months of age and 2–4 years old groups (Pre-VV R 2,253 and Post-VV R 1,077; Pre-VV R 2,400 and Post-VV R 1,165, respectively) showed the greatest reductions in incidence rates (–52.2% [IC 95% 51.3–53] P <0.001 and –51.4% [IC 95% 51–52] P <0.001). Besides, age groups not affected by vaccination (<1 year, 5–9 years, and 10–14 years) presented minor but significant reductions (–49.1% [95% CI 44.5–53.4] P < 0.001; –23% [IC95% 22.4–23.6] P <0.001, and –17% [IC95% 16.4-19] P <0.001, respectively).

Conclusion

Three years after the implementation of VZV vaccination strategy, a significant incidence rates reduction is recorded, especially in children <5 years old, despite suboptimal coverage. Improving vaccination coverage will likely reflect a greater impact on the burden of disease.

Disclosures

All authors: No reported disclosures.

Maternal immunization in Argentina: A storyline from the prospective of a middle income country

The importance of vaccination during pregnancy lies not only in directly protecting vaccinated women, but also by indirectly protecting small infants during the first few months of life. Vaccination against the flu and whooping cough is a priority within the comprehensive care strategy for pregnant women and small infants in Argentina, in the context of transitioning from child vaccination to family vaccination. In 2011, the flu vaccine was included in the National Immunization Schedule (NIS) as mandatory and free of charge, with the aim of decreasing complications and death due to influenza in the at-risk population in Argentina. The national vaccination coverage attained in pregnant women in the past 4 years (2011-2014) has been satisfactory; 88% coverage was attained in the year this program was introduced to the schedule. In the following years, coverage was maintained at greater than 95%. In February 2012, Argentina became the first country in Latin America to have universal vaccination strategy for pregnant women against whooping cough. This recommendation was implemented throughout the country by vaccination with the diphtheria toxoid, tetanus toxoid, and acellular pertussis (Tdap) vaccine starting at 20 weeks of pregnancy, with the aim of decreasing morbimortality due to whooping cough in infants under 6 months of age. The vaccine was incorporated into the NIS in 2014. More than 1,200,000 doses were applied in this period. Both vaccines showed a suitable safety profile and no serious events were reported. Argentina is an example of a middle-income country that has been able to implement a successful strategy for primary prevention through vaccines, making it a health policy.

[Pericarditis as initial presentation of disseminated meningococcal disease]

Pericarditis is a well-recognized but uncommon complication of meningococcal infection. The incidence of pericarditis complicating meningococcal disease in all age groups is reported to be 3-19%. There are few cases reported in the paediatric age group. Disseminated meningococcal disease with pericarditis, defined as purulent pericarditis with clinical evidence of disseminated meningococcemia and meningitis. We report the case of a 4-month-old male infant who presented disseminated meningococcal disease with pericarditis caused by Neisseria meningitidis serogroup B. The patient was treated with antibiotic with excellent response. It is important to point out that meningococcal disease may present in unusual forms which may lead to diagnostic and therapeutic difficulties.

[Primary meningococcal arthritis in pediatrics. Report of nine cases]

Primary meningococcal arthritis is an extremely uncommon type of invasive meningococcal disease, with an incidence of 1.5- 1.8% of all paediatric cases of pyogenic arthritis. It is defined as the presence of acute septic arthritis without association with meningitis or the classic meningococcaemia, and isolation of Neisseria meningitidis in synovial fluid and/or blood culture. Typically monoarticular, mostly affects large joints. Prognosis is excellent with appropriated treatment. The aim of this study is to report 9 cases of primary meningococcal arthritis, evaluated at Hospital de Niños "Dr. R. Gutiérrez" in a period of 3 years, and to discuss clinical and epidemiologic issues.