Plasma Extracellular Vesicles Derived from Pediatric COVID-19 Patients Modulate Monocyte and T Cell Immune Responses Based on Disease Severity.

BACKGROUND: The COVID-19 pandemic has caused significant morbidity and mortality globally. The role of plasma-derived extracellular vesicles (EVs) in pediatric COVID-19 patients remains unclear. METHODS: We isolated EVs from healthy controls (n = 13) and pediatric COVID-19 patients (n = 104) with varying severity during acute and convalescent phases using serial ultracentrifugation. EV effects on healthy PBMCs, naïve CD4+ T cells, and monocytes were assessed through in vitro assays, flow cytometry, and ELISA. RESULTS: Our findings indicate that COVID-19 severity correlates with diverse immune responses. Severe acute cases exhibited increased cytokine levels, decreased IFNγ levels, and lower CD4+ T cell and monocyte counts, suggesting immunosuppression. EVs from severe acute patients stimulated healthy cells to express higher PDL1, increased Th2 and Treg cells, reduced IFNγ secretion, and altered Th1/Th17 ratios. Patient-derived EVs significantly reduced proinflammatory cytokine production by monocytes (p < .001 for mild, p = .0025 for severe cases) and decreased CD4+ T cell (p = .043) and monocyte (p = .033) populations in stimulated healthy PBMCs. CONCLUSION: This study reveals the complex relationship between immunological responses and EV-mediated effects, emphasizing the impact of COVID-19 severity. We highlight the potential role of plasma-derived EVs in early-stage immunosuppression in severe COVID-19 patients.

The outcomes of renin-angiotensin-aldosterone system inhibition and immunosuppressive therapy in children with X-linked Alport syndrome.

BACKGROUND: Alport syndrome (AS) is characterized by progressive kidney disease. There is increasing evidence that renin-angiotensin-aldosterone system (RAAS) inhibition delays chronic kidney disease (CKD) while the effectiveness of immunosuppressive (IS) therapy in AS is still uncertain. In this study, we aimed to analyze the outcomes of pediatric patients with X-linked AS (XLAS) who received RAAS inhibitors and IS therapy. METHODS: Seventy-four children with XLAS were included in this multicenter study. Demographic features, clinical and laboratory data, treatments, histopathological examinations, and genetic analyses were analyzed retrospectively. RESULTS: Among 74 children, 52 (70.2%) received RAAS inhibitors, 11 (14.9%) received RAAS inhibitors and IS, and 11 (14.9%) were followed up without treatment. During follow-up, glomerular filtration rate (GFR) decreased < 60 ml/min/1.73 m2 in 7 (9.5%) of 74 patients (M/F=6/1). In male patients with XLAS, kidney survival was not different between RAAS and RAAS+IS groups (p=0.42). The rate of progression to CKD was significantly higher in patients with nephrotic range proteinuria and nephrotic syndrome (NS), respectively (p=0.006, p=0.05). The median age at the onset of RAAS inhibitors was significantly higher in male patients who progressed to CKD (13.9 vs 8.1 years, p=0.003). CONCLUSIONS: RAAS inhibitors have beneficial effects on proteinuria and early initiation of therapy may delay the progression to CKD in children with XLAS. There was no significant difference between the RAAS and RAAS+IS groups in kidney survival. AS patients presenting with NS or nephrotic range proteinuria should be followed up more carefully considering the risk of early progression to CKD.

A girl with Henoch Schönlein purpura associated with acute rheumatic fever and review of literature.

Aypar E, Demirtas D, Aykan HH, Kara-Eroglu F, Düzova A. A girl with Henoch Schönlein purpura associated with acute rheumatic fever and review of literature. Turk J Pediatr 2018; 60: 576-580. Henoch Schönlein purpura (HSP) with acute rheumatic fever (ARF) is a rare entity and only few cases have been reported so far. In all previously reported cases with HSP and ARF, patients initially presented with purpuric rash, arthralgia/arthritis, or abdominal pain and later diagnosed as ARF. We report an 11-year-old girl with features of both ARF and HSP. She initially presented with arthralgia and murmur. Echocardiography showed mild to moderate mitral regurgitation. Later, the clinical course was complicated by purpuric rash and abdominal pain. She was treated conservatively with IM penicillin, acetylsalicylic acid and oral prednisolone. Our patient is the first patient with HSP and ARF who initially presented with features of ARF. A review of literature revealed a limited number of cases of HSP associated with ARF (14 cases including the present case); and that the response to treatment in cases suffering from ARF associated with HSP was good; but one should also be aware of serious cardiac complications in HSP patients which may be fatal.

Mucolipidosis Type III: A Rare Disease in Differential Diagnosis of Joint Stiffness in Pediatric Rheumatology.

Mucolipidoses are metabolic disorders with autosomal recessive inheritance caused by deficiency of N-acetylglucosamine- 1-phosphotransferase leading to accumulation of glycosaminoglycans and sphingolipids intracellularly. The differential diagnosis of mucolipidosis II or III is based on the age of onset, clinical findings and degree of severity. In this article, we present four pediatric patients with mucolipidosis III or pseudo-Hurler polydystrophy who admitted to our hospital with joint stiffness. They were from consanguineous families with characteristic radiographic findings. The joints were painless and the rheumatologic evaluation and inflammation markers were negative. Mucolipidosis is a rare disease in pediatric patients to remember in differential diagnosis of joint stiffness.

Periodic Fever, Aphthosis, Pharyngitis, and Adenitis Syndrome: Analysis of Patients From Two Geographic Areas.

OBJECTIVE: Periodic fever, aphthosis, pharyngitis, and adenitis (PFAPA) syndrome is a periodic fever syndrome of childhood with an unknown etiology. Our aim was to compare the features between PFAPA syndrome patients from Turkey and those from the US, and patients with and without MEFV variants, and to test the performance of the Eurofever criteria in excluding other autoinflammatory disorders. METHODS: Seventy-one children with PFAPA syndrome, followed in Hacettepe University, in Ankara, Turkey, and 60 patients at Boston Children's Hospital in the US were enrolled. MEFV gene-variant analysis was performed in 56 patients with Sanger sequencing. RESULTS: In patients from Turkey, symptom onset was at a younger age, fever attacks were of shorter duration, and pharyngitis was more frequent, whereas adenitis, headache, and nausea/vomiting were less frequent during attacks, when compared to patients from the US (P < 0.05). More patients from the Turkish cohort were classified in the familial Mediterranean fever (FMF) group according to the Eurofever criteria than patients from the US (66.2% versus 10%; P < 0.001). Two patients were diagnosed with FMF after MEFV analysis. Twenty-one patients (37.5%) had a single MEFV variant. No significant differences in phenotype were found between patients with and without MEFV variants. CONCLUSION: The differences between patients from the Turkish and US cohorts may be due to epigenetic or environmental factors. In addition, the Eurofever FMF criteria may perform better in certain areas, if the weight of ethnic origin parameter or cutoff values were modified.

[Pediatric-onset adult type sarcoidosis: A case report]. / Sarcoidosis del adulto de inicio en la infancia: a proposito de un caso.

Sarcoidosis, a multisystem disorder of unknown etiology that involves multiple organs, is rare in children. The true incidence and prevalence of childhood sarcoidosis is unknown. As in adults, many children with sarcoidosis may be asymptomatic; the disease may remain undiagnosed. A complete and systematic evaluation of the patient is essential for the sarcoidosis diagnosis in children. Here, we describe a case of 12-year-old female who presented with 2 years history of uveitis and hepatosplenomegaly. A chest computerized tomography revealed scattered peripheral pulmonary nodules and bilateral hiliar lymphadenopathy. Bone marrow aspiration and liver biopsy were not diagnostic. A lung biopsy showed non-necrotizing epithelioid cell granulomas. She was diagnosed with sarcoidosis according to demonstration of granulomatous inflammation and the exclusion of confusable entities

La sarcoidosis, un trastorno multiorgánico de etiología desconocida que afecta varios órganos, es poco frecuente en los niños. Se desconocen la incidencia y la prevalencia reales de la sarcoidosis infantil. Al igual que en los adultos, muchos niños con sarcoidosis tal vez no presentan síntomas y la enfermedad cursa sin diagnosticarse. Es fundamental realizar una evaluación completa y sistemática del paciente para establecer el diagnóstico de sarcoidosis en los niños. Se describe el caso de una niña de 12 años con uveítis y hepatoesplenomegalia de dos años de evolución. Mediante una tomografía computarizada del tórax, se hallaron nódulos pulmonares periféricos dispersos y linfadenopatía hiliar bilateral. La aspiración de médula ósea y la biopsia de hígado no fueron diagnósticas. La biopsia de pulmón mostró granulomas de células epitelioides no necrosantes. A la paciente se le diagnosticó sarcoidosis en virtud del hallazgo de inflamación granulomatosa y de la exclusión de entidades confusoras.

Sarcoidosis del adulto de inicio en la infancia: a proposito de un caso / Pediatric-onset adult type sarcoidosis: A case report

La sarcoidosis, un trastorno multiorgánico de etiología desconocida que afecta varios órganos, es poco frecuente en los niños. Se desconocen la incidencia y la prevalencia reales de la sarcoidosis infantil. Al igual que en los adultos, muchos niños con sarcoidosis tal vez no presentan síntomas y la enfermedad cursa sin diagnosticarse. Es fundamental realizar una evaluación completa y sistemática del paciente para establecer el diagnóstico de sarcoidosis en los niños. Se describe el caso de una nina de 12 años con uveítis y hepatoesplenomegalia de dos años de evolución. Mediante una tomografía computarizada del tórax, se hallaron nódulos pulmonares periféricos dispersos y linfadenopatía hiliar bilateral. La aspiración de médula ósea y la biopsia de hígado no fueron diagnósticas. La biopsia de pulmón mostró granulomas de células epitelioides no necrosantes. A la paciente se le diagnosticó sarcoidosis en virtud del hallazgo de inflamación granulomatosa y de la exclusión de entidades confusoras.

Sarcoidosis, a multisystem disorder of unknown etiology that involves multiple organs, is rare in children. The true incidence and prevalence of childhood sarcoidosis is unknown. As in adults, many children with sarcoidosis may be asymptomatic; the disease may remain undiagnosed. A complete and systematic evaluation of the patient is essential for the sarcoidosis diagnosis in children. Here, we describe a case of 12-year-old female who presented with 2 years history of uveitis and hepatosplenomegaly. A chest computerized tomography revealed scattered peripheral pulmonary nodules and bilateral hiliar lymphadenopathy. Bone marrow aspiration and liver biopsy were not diagnostic. A lung biopsy showed non-necrotizing epithelioid cell granulomas. She was diagnosed with sarcoidosis according to demonstration of granulomatous inflammation and the exclusion of confusable entities