Respiratory Syncytial Virus (RSV) Infects CD4+ T Cells: Frequency of Circulating CD4+ RSV+ T Cells as a Marker of Disease Severity in Young Children

Background

Although human airway epithelial cells are the main target of respiratory syncytial virus (RSV), it also infects immune cells, such as macrophages and B cells. Whether T cells are permissive to RSV infection is unknown. We sought to analyze the permissiveness of CD4+ T cells to RSV infection.

Methods

CD4+ and CD8+ T cells from cord blood, healthy young children, and adults were challenged by RSV or cocultured with infected HEp-2 cells. Infection, phenotype, and cytokine production by T cells were analyzed by flow cytometry or enzyme-linked immunosorbent assay. Expression of RSV antigens by circulating CD4+ T cells from infected children was analyzed by flow cytometry, and disease severity was defined by standard criteria.

Results

CD4+ and CD8+ T cells were productively infected by RSV. Infection decreased interleukin 2 and interferon γ production as well as the expression of CD25 and Ki-67 by activated CD4+ T cells. Respiratory syncytial virus antigens were detected in circulating CD4+ and CD8+ T cells during severe RSV infection of young children. Interestingly, the frequency of CD4+ RSV+ T cells positively correlated with disease severity.

Conclusions

Respiratory syncytial virus infects CD4+ and CD8+ T cells and compromises T-cell function. The frequency of circulating CD4+ RSV+ T cells might represent a novel marker of severe infection.

[Complicated pleural infection: Analysis of 2 consecutive cohorts managed with a different policy]

INTRODUCTION

The treatment of complicated pleural infection (CPI) is controversial. Clinical guidelines recommend drainage, but with the lowest grade of evidence. Recent reports have observed good outcomes with antibiotics alone. We retrospectively compared the outcomes in two consecutive cohorts treated with different policies: the first treated according to pleural fluid charactersitics (2005-2009, interventional-prone, group 1) and the second according to clinical assessment (2010-2013, conservative-prone, group 2).

METHODS

The clinical records of all children treated for CPI in our hospital between 2005 and 2013 were thoroughly reviewed. Primary outcomes were the proportion of children drained and the length of hospital stay (LHS).

RESULTS

One hundred and nine patients (64 group 1 and 45 group 2) were analyzed. A chest tube was placed in 83% of patients in group 1 and 47% in group 2 (P<0.001). The mean LHS was 11.4 days for patients in group 1 and 12.3 for patients in group 2 (P=0.45); no differences were observed in other outcomes.

CONCLUSION

Our results add to few recent observations reporting good outcomes in many children treated with antibiotics alone and challenge the need to drain most children with CPI. Clinical trials are now needed to identify when a drainage procedure would be useful.

Postdiarrhoeal haemolytic uraemic syndrome without thrombocytopenia

BACKGROUND

Thrombocytopenia is a hallmark of postdiarrhoeal haemolytic uraemic syndrome (D+ HUS), although it can be transient and therefore undetected. There is scarce information regarding the prevalence and the course of the disease in children with D+ HUS without thrombocytopenia.

OBJECTIVE

To determine the prevalence of D+ HUS without thrombocytopenia and to describe the clinical characteristics of a series of children with this condition.

PATIENTS AND METHODS

The medical records of patients with D+ HUS hospitalised between 2000 and 2016 were reviewed to identify those without thrombocytopenia (>150,000mm³). Demographic, clinical and laboratory parameters of the selected cases were collected and descriptively analysed.

RESULTS

Nine cases (5.6%) without thrombocytopenia were identified among 161 patients hospitalised during the study period. Median age at diagnosis was 17 months (7-32) and median prodromal symptom duration was 15 days (7-21). Eight patients maintained normal urine output while the remaining one required dialysis. No patient presented with severe extrarenal compromise and/or hypertension.

CONCLUSIONS

The prevalence of non-thrombocytopenic D+ HUS was 5.6% and most cases occurred with mild forms of the disease; however, the need for dialysis in one of them indicated that normalisation of platelet count is not always an accurate marker for disease remittance. Our results also confirm that the time of onset of D+ HUS in patients without thrombocytopenia is usually delayed with respect to the initial intestinal symptoms; thus, heightened diagnostic suspicion is necessary.

High-flow nasal cannula oxygen therapy in infants with acute lower respiratory tract infection. An experience in hospitals of the City of Buenos Aires

INTRODUCTION

During the winter, infants with acute lower respiratory tract infection (ALRTI) overburden health resources. In the Autonomous City of Buenos Aires, 35 000 children are seen at the hospitals every year; 8-10 % of them are admitted to the general hospitalization ward and 5-12 % of these, to the intensive care unit (ICU). In 2017, the Department of Maternal and Child Health of the Autonomous City of Buenos Aires included high flow nasal cannula (HNFC) oxygen therapy in the ALRTI protocol in the general ward of 3 hospitals. The objective of this study was to describe its outcomes and explore the potential factors related to therapeutic failure.

METHODS

Prospective, descriptive study with infants < 18 months old hospitalized due to ALRTI in 3 hospitals (Durand, Elizalde, Gutiérrez) between June and September 2017. All children unable to comply with low-flow therapeutic targets received HNFC oxygen therapy; admission to the ICU was considered a failure.

RESULTS

Out of 522 patients hospitalized due to ALRTI, 39.7% required HNFC oxygen therapy. No significant baseline differences were observed between patients receiving HNFC and conventional oxygen therapy. Failure was observed in only 8.7% of patients with HNFC oxygen therapy. The decrease in respiratory rate was significantly greater and longer in patients with support success versus those with failure (p < 0.01). No complications were recorded.

CONCLUSIONS

The implementation of HNFC oxygen therapy under a protocol in the general wards was a safe measure. Patients with therapeutic failure showed a smaller reduction in respiratory rate during treatment.

[Childhood pemphigus vulgaris, a case report]

Pemphigus vulgaris is a chronic disease that is characterized by flaccid blisters and erosions, caused by immunoglobulin G autoantibodies against epidermal components. It is highly unusual in the pediatric population; it represents the 1.4 - 2.9% of the total cases. We present a case of pemphigus vulgaris in a 12 year old girl, which has implied a challenge both in its diagnosis and in its treatment.

[Consensus on treatment of multisystemic inflammatory syndrome associated with COVID-19]

The pandemic caused by the SARS-CoV-2 virus declared by the WHO in March 11th 2020, affects a small number of pediatric patients, who mostly present mild respiratory compromise and favorable evolution. However began to be observed in previously healthy children, an increase in cases defined as "Multisystemic Inflammatory Syndrome" (MIS-C) or "Kawasaki-like" post-COVID 19 (KLC) that evolve to shock and require hospitalization in the Pediatric Intensive Care Unit. MIS-C and KL-C are characterized by fever; signs of inflammation, gastrointestinal symptoms, and cardiovascular dysfunction, associated with sever forms of presentation with higher incidence of hypotension and/or shock. In the laboratory, markers of inflammation, hypercoagulability and myocardial damage are observed. Firstline drug treatment consists of intravenous immunoglobulin plus oral acetylsalicylic acid. A multidisciplinary approach is recommended for an accurate diagnosis and an early and effective treatment, in order to reduce morbidity and mortality.

Fcγ Receptor IIa (FCGR2A) Polymorphism Is Associated With Severe Respiratory Syncytial Virus Disease in Argentinian Infants

Background

Most patients with respiratory syncytial virus (RSV) infection requiring hospitalization have no risk factors for severe disease. Genetic variation in the receptor for the Fc portion of IgG (FcγR) determines their affinity for IgG subclasses driving innate and adaptive antiviral immunity. We investigated the relationship between FcγRIIa-H131R polymorphism and RSV disease.

Methods

Blood samples were collected from 182 infants ≤24-month-old (50 uninfected, 114 RSV-infected with moderate course and 18 suffering severe disease). FcγRIIa-H131R SNP genotypic frequencies (HH, HR, RR) and anti-RSV IgG1, IgG2 and IgG3 levels were studied.

Results

Genotypic frequencies for FcγRIIa-H131R SNP were comparable between uninfected and RSV-infected infants. In contrast, we found a significant higher frequency of HH genotype in severe RSV-infected children compared to moderate patients. Among severe group, HH infants presented more factors associated to severity than HR or RR patients did. Furthermore, compared to moderate RSV-infected infants, severe patients showed higher levels of anti-RSV IgG1 and IgG3.

Conclusions

We found an association between an FcγRIIa (H131) polymorphism and severe RSV disease, which points towards a critical role for interactions between FcγRs and immune complexes in RSV pathogenesis. This genetic factor could also predict the worse outcome and identify those infants at risk during hospitalization.

[Consensus on treatment of multisystemic inflammatory syndrome associated with COVID-19]

The pandemic caused by the SARS-CoV-2 virus declared by the WHO in March 11th 2020, affects a small number of pediatric patients, who mostly present mild respiratory compromise and favorable evolution. However began to be observed in previously healthy children, an increase in cases defined as "Multisystemic Inflammatory Syndrome" (MIS-C) or "Kawasaki-like" post-COVID 19 (KLC) that evolve to shock and require hospitalization in the Pediatric Intensive Care Unit. MIS-C and KL-C are characterized by fever; signs of inflammation, gastrointestinal symptoms, and cardiovascular dysfunction, associated with sever forms of presentation with higher incidence of hypotension and/or shock. In the laboratory, markers of inflammation, hypercoagulability and myocardial damage are observed. Firstline drug treatment consists of intravenous immunoglobulin plus oral acetylsalicylic acid. A multidisciplinary approach is recommended for an accurate diagnosis and an early and effective treatment, in order to reduce morbidity and mortality.

[Consensus on treatment of multisystemic inflammatory syndrome associated with COVID-19]

The pandemic caused by the SARS-CoV-2 virus declared by the WHO in March 11th 2020, affects a small number of pediatric patients, who mostly present mild respiratory compromise and favorable evolution. However began to be observed in previously healthy children, an increase in cases defined as "Multisystemic Inflammatory Syndrome" (MIS-C) or "Kawasaki-like" post-COVID 19 (KLC) that evolve to shock and require hospitalization in the Pediatric Intensive Care Unit. MIS-C and KL-C are characterized by fever; signs of inflammation, gastrointestinal symptoms, and cardiovascular dysfunction, associated with sever forms of presentation with higher incidence of hypotension and/or shock. In the laboratory, markers of inflammation, hypercoagulability and myocardial damage are observed. Firstline drug treatment consists of intravenous immunoglobulin plus oral acetylsalicylic acid. A multidisciplinary approach is recommended for an accurate diagnosis and an early and effective treatment, in order to reduce morbidity and mortality.

ATP-P2X7R pathway activation limits the Tfh cell compartment during pediatric RSV infection

Background

Follicular helper T cells (Tfh) are pivotal in B cell responses. Activation of the purinergic receptor P2X7 on Tfh cells regulates their activity. We investigated the ATP-P2X7R axis in circulating Tfh (cTfh) cells during Respiratory Syncytial Virus (RSV) infection.

Methods

We analyzed two cohorts: children with RSV infection (moderate, n=30; severe, n=21) and healthy children (n=23). We utilized ELISA to quantify the levels of PreF RSV protein-specific IgG antibodies, IL-21 cytokine, and soluble P2X7R (sP2X7R) in both plasma and nasopharyngeal aspirates (NPA). Additionally, luminometry was employed to determine ATP levels in plasma, NPA and supernatant culture. The frequency of cTfh cells, P2X7R expression, and plasmablasts were assessed by flow cytometry. To evaluate apoptosis, proliferation, and IL-21 production by cTfh cells, we cultured PBMCs in the presence of Bz-ATP and/or P2X7R antagonist (KN-62) and a flow cytometry analysis was performed.

Results

In children with severe RSV disease, we observed diminished titers of neutralizing anti-PreF IgG antibodies. Additionally, severe infections, compared to moderate cases, were associated with fewer cTfh cells and reduced plasma levels of IL-21. Our investigation revealed dysregulation in the ATP-P2X7R pathway during RSV infection. This was characterized by elevated ATP levels in both plasma and NPA samples, increased expression of P2X7R on cTfh cells, lower levels of sP2X7R, and heightened ATP release from PBMCs upon stimulation, particularly evident in severe cases. Importantly, ATP exposure decreased cTfh proliferative response and IL-21 production, while promoting their apoptosis. The P2X7R antagonist KN-62 mitigated these effects. Furthermore, disease severity positively correlated with ATP levels in plasma and NPA samples and inversely correlated with cTfh frequency.

Conclusion

Our findings indicate that activation of the ATP-P2X7R pathway during RSV infection may contribute to limiting the cTfh cell compartment by promoting cell death and dysfunction, ultimately leading to increased disease severity.

[Psychodrama in psychotic patients]

This experience was carried out over the years 1979/81 and 1983/4 at the Magnan ward of the Braulio Moyano Women's Neuropsychiatric Hospital in Buenos Aires, Argentina. Theory and the techniques of Psychodrama were applied to different groups of chronic psychotics, one of those groups being in a deep state of deterioration. Objects and therapeutic aims were to achieving changes in the patients' behavior, improving their socialization level as well as their communication links with their inmates and both their doctors and nurses. By means of both role playing and the nucleus of both the Ego and Scheme of Roles as a frame of reference it was aimed at recovering patients' integrative activity, thus increasing their re-adaptability to the familiar group an the society structure as well.

[Tubular sclerosis]

Tubular sclerosis is a pulp-dentin complex defensive response to several physiologic and pathologic stimuli; it leads to an increasing tubular obliteration which enormously reduces dentinal permeability. Its typical structural features are either increased peritubular dentin thickness or "caries crystals". Pathogenesis is a much debated question: some authors assert that peritubular dentin thickening is the main liable for sclerosis while others support a centrifugal theory. Another point of view considers its pathogenesis the result of many integrated mechanism.

Esophageal achalasia: A case report in an adolescent

Esophageal achalasia is an uncommon disease in pediatrics. With an insidious clinical presentation, diagnosis is delayed. Here we describe a case of esophageal achalasia in a 16-year-old girl, with the typical delay in consultation and diagnosis. Although pneumatic balloon dilatation has been described as the best therapeutic option for type II achalasia, it was ineffective in our patient and she required Heller extramucosal myotomy with gastroesophageal fundoplication for reflux.

Western equine encephalitis: a pediatric case report

Western equine encephalitis (WEE) is a zoonotic disease caused by an RNA virus of the genus Alphavirus, and humans are accidental hosts. Although most patients do not develop symptoms upon infection, children are at higher risk for neurological involvement. Here we describe the case of a previously healthy 13-year-old male patient who lived in an urban area in the province of Buenos Aires, Argentina, who was hospitalized and diagnosed with meningoencephalitis. Due to the torpid course of his condition and because none of the most frequent microorganisms were isolated, a test for IgG antibodies for WEE virus in blood and cerebrospinal fluid was requested; both samples were positive. WEE virus is often an underdiagnosed cause of encephalitis and should be taken into consideration in both rural and urban areas.

[The madness of "The Quixote"]

The aim of this fiction psychiatric article, is to take a psychiatric look to El Quijote and to determine his strange and fascinating madness. His symptoms are analyzed as those of any patient and the conclusion is that he had a pre senile paranoia. This diagnosis, that gratifies clinicians curiosity, says nothing about the charm of his unusual mental profile or the captivating fascination of his nobility and poetry.