Disseminated Tuberculosis Mimicking as Crohn's Disease in a Paediatric Patient

Tuberculosis is an important infectious disease for children worldwide. The clinical presentation of tuberculosis in children is diverse and, depending on the affected organs, it is often accompanied with nonspecific symptoms that can mimic other diseases. In this report, we present a case of disseminated tuberculosis in an 11-year-old boy with intestinal followed by pulmonary involvement. The diagnosis was delayed for several weeks due to the clinical picture which was mimicking Crohn's disease, the known difficulties in diagnostic tests and the improvement on meropenem. This case demonstrates the importance of a detailed microscopic examination of gastrointestinal biopsies and the tuberculostatic effect of meropenem which physicians should be aware of.

The burden and surveillance of RSV disease in young children in Belgium-expert opinion

Infections with respiratory syncytial virus (RSV) can cause severe disease. In young children, RSV is the most common cause of lower respiratory tract illness and life-threatening infections most commonly occur in the first years of life. In adults, elderly and immunocompromised people are most vulnerable. Recently there has been an acceleration in the development of candidate RSV vaccines, monoclonal antibodies and therapeutics which are expected to become available in Europe within the next 2-10 years. Understanding the true burden of childhood RSV disease will become very important to support public health authorities and policy makers in the assessment of new therapeutic opportunities against RSV disease. A systematic literature search was performed to map local data on the burden of RSV disease and to evaluate available RSV surveillance systems. A group of 9 paediatric infectious diseases specialists participated in an expert panel. The purpose of this meeting was to evaluate and map the burden associated with RSV infection in children, including patient pathways and the epidemiological patterns of virus circulation in Belgium. Sources of information on the burden of RSV disease in Belgium are very limited. For the outpatient setting, it is estimated that 5-10% of young patients seen in primary care are referred to the hospital. Around 3500 children between 0 and 12 months of age are hospitalized for RSV-bronchiolitis every year and represent the majority of all hospitalizations. The current Belgian RSV surveillance system was evaluated and found to be insufficient. Knowledge gaps are highlighted and future perspectives and priorities offered.

CONCLUSION

The Belgian population-based RSV surveillance should be improved, and a hospital-led reporting system should be put in place to enable the evaluation of the true burden of RSV disease in Belgium and to improve disease management in the future.

WHAT IS KNOWN

• RSV bronchiolitis is a very important cause of infant hospitalization. • The burden of disease in the community is poorly studied and underestimated.

WHAT IS NEW

• This expert opinion summarizes knowledge gaps and offers insights that allow improvement of local surveillance systems in order to establish a future-proof RSV surveillance system.

Rubella Virus Infected Macrophages and Neutrophils Define Patterns of Granulomatous Inflammation in Inborn and Acquired Errors of Immunity

Rubella virus (RuV) has recently been found in association with granulomatous inflammation of the skin and several internal organs in patients with inborn errors of immunity (IEI). The cellular tropism and molecular mechanisms of RuV persistence and pathogenesis in select immunocompromised hosts are not clear. We provide clinical, immunological, virological, and histological data on a cohort of 28 patients with a broad spectrum of IEI and RuV-associated granulomas in skin and nine extracutaneous tissues to further delineate this relationship. Combined immunodeficiency was the most frequent diagnosis (67.8%) among patients. Patients with previously undocumented conditions, i.e., humoral immunodeficiencies, a secondary immunodeficiency, and a defect of innate immunity were identified as being susceptible to RuV-associated granulomas. Hematopoietic cell transplantation was the most successful treatment in this case series resulting in granuloma resolution; steroids, and TNF-α and IL-1R inhibitors were moderately effective. In addition to M2 macrophages, neutrophils were identified by immunohistochemical analysis as a novel cell type infected with RuV. Four patterns of RuV-associated granulomatous inflammation were classified based on the structural organization of granulomas and identity and location of cell types harboring RuV antigen. Identification of conditions that increase susceptibility to RuV-associated granulomas combined with structural characterization of the granulomas may lead to a better understanding of the pathogenesis of RuV-associated granulomas and discover new targets for therapeutic interventions.

Infliximab for Paradoxical Reactions in Pediatric Central Nervous System Tuberculosis

Paradoxical reactions in central nervous system tuberculosis (CNS-TB) are associated with significant morbidity and mortality. We describe 4 HIV-uninfected children treated for CNS-TB with severe paradoxical reactions unresponsive to corticosteroids. All made recovery after treatment with infliximab, highlighting the safety and effectiveness of infliximab for this complication, and need for prospective trials.

Bronchiolitis in COVID-19 times: a nearly absent disease?

Stay-at-home orders, physical distancing, face masks and other non-pharmaceutical interventions (NPIs) do not only impact COVID-19, but also the dynamics of various other infectious diseases. Bronchiolitis is a clinically diagnosed viral infection of the lower respiratory tract, and causes a yearly seasonal wave of admissions in paediatric wards worldwide. We counted 92,5% less bronchiolitis hospitalisations in Antwerp before the expected end of the peak this year (of which only 1 RSV positive), as compared to the last 3 years. Furthermore, there was a >99% reduction in the number of registered RSV cases in Belgium.Conslusion: The 2020 winter bronchiolitis peak is hitherto nonexistent, but we fear a 'delayed' spring/summer bronchiolitis peak when most NPIs will be relaxed and pre-pandemic life restarts. What is known? • Bronchiolitis causes a yearly seasonal wave of admissions in paediatric departments worldwide. • Non-pharmaceutical interventions (NPIs) do not only impact COVID-19, but also the dynamics of various other infectious diseases. What is new? • The 2020 winter bronchiolitis peak is hitherto nonexistent. • A 'delayed' spring or summer bronchiolitis peak could happen when most NPIs will be relaxed and pre-pandemic life restarts.

Quantifying superspreading for COVID-19 using Poisson mixture distributions

The number of secondary cases is an important parameter for the control of infectious diseases. When individual variation in disease transmission is present, like for COVID-19, the number of secondary cases is often modelled using a negative binomial distribution. However, this may not be the best distribution to describe the underlying transmission process. We propose the use of three other offspring distributions to quantify heterogeneity in transmission, and we assess the possible bias in estimates of the offspring mean and its overdispersion when the data generating distribution is different from the one used for inference. We find that overdispersion estimates may be biased when there is a substantial amount of heterogeneity, and that the use of other distributions besides the negative binomial should be considered. We revisit three previously analysed COVID-19 datasets and quantify the proportion of cases responsible for 80% of transmission, p 80% , while acknowledging the variation arising from the assumed offspring distribution. We find that the number of secondary cases for these datasets is better described by a Poisson-lognormal distribution.

Exposure to cough aerosols and development of pulmonary COVID-19

We hypothesized that most patients with severe pulmonary COVID-19 were exposed to cough aerosols. Among patients that were almost 100% certain which person infected them, only 14 out of 38 overall, and 9 out of 25 hospitalized patients requiring supplemental oxygen, were infected by someone who coughed, which did not support our hypothesis. Talking, especially with a loud voice, could be an alternative source generating SARS-CoV-2 aerosols. Further research is needed to determine how SARS-CoV-2 spreads. Avoiding to talk when you are not wearing your mask and not talking with a loud voice, 'voice etiquette', could be other public health interventions worthwhile exploring.

Mass masking as a way to contain COVID-19 and exit lockdown in low- and middle-income countries

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Proper use of face masks by the general public can curtail COVID-19 transmission.

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The World Health Organization encourages countries to adopt mass masking policies.

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Targeted strategies can increase face mask use even in resource-limited settings.

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Impact of mass masking on COVID-19 transmission to be assessed via community trials.

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Efficacy of surgical vs cloth masks for COVID-19 warrants further investigations.

In new guidelines published on June 5th 2020, the World Health Organization (WHO) recommends that in areas with ongoing COVID-19 community transmission, governments should encourage the general public to wear face masks in specific situations and settings as part of a comprehensive approach to suppress COVID-19 transmission. Recent online surveys in 206,729 persons residing in nine low- and middle-income countries showed that 32.7%-99.7% of respondents used face masks with significant differences across age groups and sexes. Targeted health promotion strategies and government support are required to increase mask use by the general population.

Baylisascariasis: A young boy with neural larva migrans due to the emerging raccoon round worm

A 17-month-old boy from Vancouver, Canada, presented with a 5-day history of progressive somnolence, ataxia, and torticollis. Additional investigations revealed eosinophilic encephalitis with deep white matter changes on MR imaging. On day 13, serology came back positive for Baylisascaris procyonis antibodies. While prophylaxis after ingestion of soil or materials potentially contaminated with raccoon feces can prevent baylisascariasis, timely treatment can sometimes alter a disastrous outcome. Populations of infected raccoons are propagating globally, but cases of Baylisascaris neural larva migrans have so far only been reported from North America.

Contribution of QuantiFERON-TB Gold-in-Tube to the Diagnosis of Mycobacterium tuberculosis Infection in Young Children in a Low TB Prevalence Country

Introduction: Interferon Gamma Release Assay (IGRA) has proven to be a useful test to evaluate the immune response to Mycobacterium tuberculosis antigens in children over the age of 5 years as an alternative to tuberculin skin testing (TST). Much less is known about its performance in younger children, who are at higher risk for developing tuberculosis (TB) disease after exposure. We aimed to evaluate the accuracy of using IGRA in TB screening in this population. Methods: Children below the age of 5 years at high risk for TB infection were prospectively enrolled, to compare the performance of TST and the QuantiFERON-TB Gold-In-Tube test (QFT). Children were treated in accordance with the diagnosis made at baseline and followed-up for 12 months. Results: We included a total of 60 children of which 97 blood samples were available for analysis. There was 90.72% agreement between TST and QFT (Kappa test 0.59, moderate agreement). With TST as a reference, the QFT positive predictive value was 0.72 and the negative predictive value 0.93. Discordant results were observed with 6% TST+/QFT- paired tests. When we restricted the comparison of TST and QFT to non-BCG-vaccinated children, the degree of agreement was more substantial (95%, Kappa test 0.75) and the negative predictive value was 0.99. We observed 3% discordant TST-/QFT+ results. All children with active TB disease had concordant positive QFT results, with QFT values above 4.00 IU/ml. Conclusion: In a low TB prevalence country, serial testing of QFT was found to produce a moderate agreement with TST results. False positive QFT results would have been eliminated by using a higher cutoff without misdiagnosing the children with TB disease. Some of the false negative QFT results could be explained by false positive TST results on consecutive testing. For now the most prudent approach would be to consider discordant QFT-/TST+ results as false negative QFT results, taking into account the young age of our population and the potential risk for evolution to active TB disease.

Bilateral subacute lacrimal gland enlargement mimicking dacryoadenitis in a 7-year-old boy: a rare adverse effect of valproic acid (sodium valproate)

A healthy 7-year-old boy presented with bilateral symmetrical lacrimal gland enlargement; a week later salivary gland enlargement was also noted. Clinical investigations suggested no diagnosis, and surgical biopsy was considered. Valproic acid (sodium valproate), which he was taking for absence seizures, has been reported to cause salivary gland swelling in adults. Suspecting that a similar mechanism could be causal, the drug was discontinued. Complete resolution of the lacrimal and salivary gland enlargement rapidly ensued. This is the first report of lacrimal gland enlargement caused by valproic acid.

Immune vulnerability of infants to tuberculosis

One of the challenges faced by the infant immune system is learning to distinguish the myriad of foreign but nonthreatening antigens encountered from those expressed by true pathogens. This balance is reflected in the diminished production of proinflammatory cytokines by both innate and adaptive immune cells in the infant. A downside of this bias is that several factors critical for controlling Mycobacterium tuberculosis infection are significantly restricted in infants, including TNF, IL-1, and IL-12. Furthermore, infant T cells are inherently less capable of differentiating into IFN- γ -producing T cells. As a result, infected infants are 5-10 times more likely than adults to develop active tuberculosis (TB) and have higher rates of severe disseminated disease, including miliary TB and meningitis. Infant TB is a fundamentally different disease than TB in immune competent adults. Immunotherapeutics, therefore, should be specifically evaluated in infants before they are routinely employed to treat TB in this age group. Modalities aimed at reducing inflammation, which may be beneficial for adjunctive therapy of some forms of TB in older children and adults, may be of no benefit or even harmful in infants who manifest much less inflammatory disease.

Training health care workers to promote HIV services for patients with tuberculosis in the Democratic Republic of Congo

BACKGROUND

HIV counseling and testing, HIV prevention and provision of HIV care and support are essential activities to reduce the burden of HIV among patients with TB, and should be integrated into routine TB care.

METHODS

The development of training materials to promote HIV services for TB patients involved the definition of target health care workers (HCWs); identification of required tasks, skills and knowledge; review of international guidelines; and adaptation of existing training materials for voluntary counseling and testing, prevention of mother-to-child transmission of HIV, and management of opportunistic infections (OIs). Training effectiveness was assessed by means of questionnaires administered pre- and post-training, by correlating post-training results of HCWs with the centre's HIV testing acceptance rates, and through participatory observations at the time of on-site supervisory visits and monthly meetings.

RESULTS

Pre-training assessment identified gaps in basic knowledge of HIV epidemiology, the link between TB and HIV, interpretation of CD4 counts, prevention and management of OIs, and occupational post-exposure prophylaxis (PEP). Opinions on patients' rights and confidentiality varied. Mean test results increased from 72% pre-training to 87% post-training (p<0.001). Important issues regarding HIV epidemiology and PEP remained poorly understood post-training. Mean post-training scores of clinic's HCWs were significantly correlated with the centre's HIV testing acceptance rates (p=0.01). On-site supervisory visits and monthly meetings promoted staff motivation, participatory problem solving and continuing education. Training was also used as an opportunity to improve patient-centred care and HCWs' communication skills.

CONCLUSION

Many HCWs did not possess the knowledge or skills necessary to integrate HIV activities into routine care for patients with TB. A participatory approach resulted in training materials that fulfilled local needs.