Analysis of a Cohort of 165 Pediatric Patients with Human Bocavirus Infection and Comparison between Mono-Infection and Respiratory Co-Infections: A Retrospective Study

INTRODUCTION

Human Bocavirus (HBoV) is mainly associated with respiratory tract infections. However, its role as respiratory pathogen is not fully understood for a high co-infection rate in symptomatic patients and a significant HBoV detection rate in asymptomatic subjects. This study aimed to describe a large cohort of children with HBoV infection and to compare HBoV mono-infection and co-infections.

METHODS

We retrospectively reviewed data from 165 children admitted to Meyer Children's Hospital IRCCS from March 2022 to March 2023 with the diagnosis of HBoV infection, detected using Reverse Transcription qPCR from nasal swabs. Thereafter, we compared patients with HBoV mono-infection (Group A) and those with HBoV co-infections (Group B) in terms of disease severity, established by the length of stay (LOS), the requirement of Pediatric Intensive Care Unit (PICU), and advanced respiratory support (ARS).

RESULTS

The median age was 1.5 years; 80% of patients presented with respiratory symptoms. The discharge rate from the emergency department (ED) within 24 h was 42.4%. Most cases (57.6%) were hospitalized, and 7.3% were admitted to PICU due to respiratory failure. Group A comprised 69 patients, and Group B 96 children (95% viral co-infections, 2% bacterial, 3% viral and bacterial). Group A and Group B were similar in hospitalization rate but differed significantly in LOS (median 3 vs. 5 days) and requirement of PICU admission (0 vs. 12 patients, p < 0.001). Patients with a respiratory disease history (17.5%) showed significantly longer LOS and more necessity of inhaled bronchodilator therapy.

CONCLUSIONS

HBoV should be considered a relevant respiratory pathogen especially in viral co-infections. Patients with HBoV co-infections have a higher risk of necessitating advanced respiratory support with more PICU admission and longer LOS; a previous respiratory disease puts them at a higher risk of longer hospitalization.

The diagnostic role of pathergy test in patients with Behçet's disease from the Western Europe

The aim of the study is to evaluate the frequency and features of positive pathergy test (PPT) in Italy, its role in the diagnosis of Behçet's disease (BD), and any association with other BD-related manifestations. 52 BD patients, 52 patients with axial spondyloarthritis (ax-SpA), and 26 healthy controls (HCs) underwent intradermal injection of normal saline and intradermal needle soaked with fresh self-saliva. The results of pathergy tests were statistically analysed in the light of demographic, clinical, and therapeutic features of subjects enrolled. Pathergy test performed with saline resulted always negative in all groups. Skin prick test using self-saliva resulted in the occurrence of a papule in 3 (5.8%) BD patients and in 1 (1.9%) patient with ax-SpA. A ≥ 15 mm erythematous area surrounding the needle prick site was observed in 22 (42.3%) BD patients, 5 (9.6%) patients with ax-SpA, and 2 (7.7%) HCs (p = 0.00002). The frequency of skin erythema was significantly more frequent in patients with BD than those with ax-SpA (p < 0.0001) and HCs (p = 0.003). No statistically significant differences were observed between ax-SpA patients and HCs (p = 1.000). The occurrence of skin erythema at pathergy test was not associated with any BD-related clinical manifestation. Erythema at self-saliva prick test presented a sensitivity of 42.31% (CI 28.73-56.80%) and a specificity of 91.03% (CI 82.38-96.32%). The development of a ≥ 15 mm erythematous area at self-saliva prick test could be sufficient to unveil the hyper-reactivity of the innate immune system in BD patients from Western Europe, where the development of skin erythema shows good sensitivity and specificity toward the diagnosis of BD.

Development and implementation of the AIDA International Registry for patients with Behçet's disease

Purpose of the present paper is to point out the design, development and deployment of the AutoInflammatory Disease Alliance (AIDA) International Registry dedicated to pediatric and adult patients with Behçet's disease (BD). The Registry is a clinical physician-driven non-population- and electronic-based instrument implemented for the retrospective and prospective collection of real-life data about demographics, clinical, therapeutic, laboratory, instrumental and socioeconomic information from BD patients; the Registry is based on the Research Electronic Data Capture (REDCap) tool, which is thought to collect standardised information for clinical real-life research, and has been realised to change over time according to future scientific acquisitions and potentially communicate with other existing and future Registries dedicated to BD. Starting from January 31st, 2021, to February 7th, 2022, 110 centres from 23 countries in 4 continents have been involved. Fifty-four of these have already obtained the approval from their local Ethics Committees. Currently, the platform counts 290 users (111 Principal Investigators, 175 Site Investigators, 2 Lead Investigators, and 2 data managers). The Registry collects baseline and follow-up data using 5993 fields organised into 16 instruments, including patient's demographics, history, clinical manifestations and symptoms, trigger/risk factors, therapies and healthcare access. The development of the AIDA International Registry for BD patients will facilitate the collection of standardised data leading to real-world evidence, enabling international multicentre collaborative research through data sharing, international consultation, dissemination of knowledge, inclusion of patients and families, and ultimately optimisation of scientific efforts and implementation of standardised care.Trial registration NCT05200715 in 21/01/2022.

POS1373 THE DIAGNOSTIC ROLE OF PATHERGY TEST IN PATIENTS WITH BEHÇET’S DISEASE FROM WESTERN EUROPE

Background

pathergy is the term used to describe the hyper-reactivity of the skin in response to a minimal trauma, as the consequence of an exacerbated response of the innate immune system [1]. Pathergy test has a central role for the diagnosis of Behçet’s disease (BD), especially in doubtful and atypical cases. However, while its incidence has been decreasing over the past few decades, there are significant variations in the frequency of pathergy among different geographic contexts [2]. These aspects affect the diagnostic role of pathergy test for patients with suspected BD.

Objectives

to evaluate the frequency and features of positive pathergy test (PPT) in Italy, its role in the diagnosis of BD, and any association with other BD-related manifestations.

Methods

29 BD patients, 15 patients with spondyloarthritis (SpA) and 19 healthy controls (HCs) underwent two types of pathergy test, which were performed on the hairless part of the volar forearm ipsilaterally: intradermal injection of 0.5 ml normal saline and intradermally needle soaked with fresh self-saliva. Both pricks were done with a monouse 25 gauge hypodermic needle inserted with a vertical approach at a depth of 5 mm into the skin. The needle was withdrawn with a twisting movement. Skin reactions were observed 48 hours after prick. The results of pathergy tests were statistically analysed in the light of demographic, clinical, and therapeutic features of subjects enrolled. The BD activity at the time of the pathergy test was assessed with the Behçet’s Disease Current Activity Form (BDCAF) [3].

Results

pathergy test performed with saline solution resulted always negative in all groups. Skin prick test using self-saliva resulted in the occurrence of a papule in 2 (6.9%) BD patients and in 1 (6.7%) patient with SpA. A ≥15 mm erythematous area surrounding the needle prick site was observed in 12 (41.4%) BD patients, in 4 (26.7%) patients with SpA (including the patient with the papule), and in 1 (5.6%) HCs (p=0.022). The frequency of skin erythema was significantly higher among BD patients compared to HCs (p=0.015); no statistically significant differences were observed between BD and SpA patients (p=0.53) as well as between SpA patients and HC (p=0.21). The occurrence of skin erythema was not associated with any of the BD-related clinical manifestations. No statistically significant differences were observed between BD patients with positive and negative pathergy test according to sex (p=0.873); HLA-B51 positivity (p-value=0.461); age at the pathergy test (p=0.929); and disease duration at the pathergy test (p=0.487). The mean BDCAF was 1.33±0.65 among patients with PPT and 0.82±0.72 among patients with negative pathergy test (p=0.092). Erythema at self-saliva prick test showed a sensitivity of 41.4% (C.I. 23.52%-61.06%) and a specificity of 85.3% (C.I. 68.94%-95.05%); the positive likelihood ratio was 2.81 (C.I. 1.12-7.05) and the negative likelihood ratio was 0.69 (C.I. 0.49-0.96).

Conclusion

this study confirms the lower frequency of PPT in Western European BD patients if considering the development of a papule or a pustule in the site of pathergy test. Conversely, the onset of a ≥15 mm erythematous area surrounding the prick site could be sufficient to unveil the hyper-reactivity of the innate immune system in BD patients from Western Europe. Pathergy test is not pathognomonic of BD, as its positivity can be also observed in other innate immune system disorders, as observed for SpA patients.

References

[1]Gül A, Esin S, Dilsen N, Koniçe M, Wigzell H, Biberfeld P. Immunohistology of skin pathergy reaction in Behçet’s disease. Br J Dermatol 1995;132:901-7. doi: 10.1111/j.1365-2133.1995.tb16946.x.

[2]Davatchi F, Chams-Davatchi C, Ghodsi Z, Shahram F, Nadji A, Shams H, et al. Diagnostic value of pathergy test in Behcet’s disease according to the change of incidence over the time. Clin Rheumatol. 2011;30:1151–1155. doi: 10.1007/s10067-011-1694-5.

[3]Lawton G, Bhakta BB, Chamberlain MA, Tennant A. The Behcet’s disease activity index. Rheumatology (Oxford) 2004;43:73-8. doi: 10.1093/rheumatology/keg453.

Disclosure of Interests

None declared

Clinical profile and evolution of patients with juvenile-onset Behçet's syndrome over a 25-year period: insights from the AIDA network

Behçet's syndrome (BS) represents an understudied topic in pediatrics: the main aims of our study were to characterize demographic and clinical features of a cohort of BS patients with juvenile-onset managed in three tertiary referral centers in Italy, evaluate their evolution in the long-term, and detect any potential differences with BS patients having an adult-onset. Medical records of 64 juvenile-onset and 332 adult-onset BS followed-up over a 2-year period were retrospectively analyzed and compared. Mean age ± SD of first symptom-appearance was 10.92 ± 4.34 years with a female-to-male ratio of 1.06:1. Mucocutaneous signs were the most frequent initial manifestations, followed by uveitis. Throughout the disease course, genital aphthae (76.56%) and pseudofolliculitis (40.63%) prevailed among the mucocutaneous signs, while major organ involvement was represented by gastrointestinal and ocular involvement (43.75 and 34.38%, respectively). No significant differences emerged for both mucocutaneous signs and specific major organ involvement between juvenile-onset and adult BS patients. After excluding nonspecific abdominal pain, juvenile-onset BS patients were less frequently characterized by the development of major organ involvement (p = 0.027). Logistic regression detected the juvenile-onset as a variable associated with reduced risk of long-term major organ involvement (OR 0.495 [0.263-0.932], p = 0.029). In our cohort, juvenile-onset BS resembled the clinical spectrum of adult-onset patients. Pediatric patients with a full-blown disease at onset showed a more frequent mucocutaneous involvement. In addition, patients with juvenile-onset seemed to develop less frequently major organ involvement and had an overall less severe disease course.

Biotechnological Agents for Patients With Tumor Necrosis Factor Receptor Associated Periodic Syndrome-Therapeutic Outcome and Predictors of Response: Real-Life Data From the AIDA Network

Objective: To describe the role of biotechnological therapies in patients with tumor necrosis factor receptor associated periodic syndrome (TRAPS) and to identify any predictor of complete response. Methods: Clinical, laboratory, and therapeutic data from 44 Caucasian TRAPS patients treated with biologic agents were retrospectively collected in 16 Italian tertiary Centers. Results: A total of 55 biological courses with anakinra (n = 26), canakinumab (n = 16), anti-TNF-α agents (n = 10), and tocilizumab (n = 3) were analyzed. A complete response was observed in 41 (74.5%) cases, a partial response in 9 (16.4%) cases and a treatment failure in 5 (9.1%) cases. The frequency of TRAPS exacerbations was 458.2 flare/100 patients-year during the 12 months prior to the start of biologic treatment and 65.7 flare/100 patients-years during the first 12 months of therapy (p < 0.0001). The median duration of attacks was 5.00 (IQR = 10.50) days at the start of biologics and 1.00 (IQR = 0.00) days at the 12-month assessment (p < 0.0001). Likewise, a significant reduction was observed in the Autoinflammatory Disease Activity Index during the study period (p < 0.0001). A significant corticosteroid sparing effect was observed as early as the first 12 months of treatment both in the number of patients requiring corticosteroids (p = 0.025) and in the dosages employed (p < 0.0001). A significant reduction was identified in the erythrocyte sedimentation rate (p < 0.0001), C reactive protein (p < 0.0001), serum amyloid A (p < 0.0001), and in the 24-h proteinuria dosage during follow-up (p = 0.001). A relapsing-remitting disease course (OR = 0.027, C.I. 0.001-0.841, p = 0.040) and the frequency of relapses at the start of biologics (OR = 0.363, C.I. 0.301-0.953, p = 0.034) were significantly associated with a complete response. No serious adverse events were observed. Conclusions: Treatment with biologic agents is highly effective in controlling clinical and laboratory TRAPS manifestations. Patients with a relapsing-remitting course and a lower frequency of flares at the start of treatment show more likely a complete response to biologic agents.