The Immunology of Multisystem Inflammatory Syndrome in Children with COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is typically very mild and often asymptomatic in children. A complication is the rare multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19, presenting 4-6 weeks after infection as high fever, organ dysfunction, and strongly elevated markers of inflammation. The pathogenesis is unclear but has overlapping features with Kawasaki disease suggestive of vasculitis and a likely autoimmune etiology. We apply systems-level analyses of blood immune cells, cytokines, and autoantibodies in healthy children, children with Kawasaki disease enrolled prior to COVID-19, children infected with SARS-CoV-2, and children presenting with MIS-C. We find that the inflammatory response in MIS-C differs from the cytokine storm of severe acute COVID-19, shares several features with Kawasaki disease, but also differs from this condition with respect to T cell subsets, interleukin (IL)-17A, and biomarkers associated with arterial damage. Finally, autoantibody profiling suggests multiple autoantibodies that could be involved in the pathogenesis of MIS-C.

Pathogenetic determinants in Kawasaki disease: the haematological point of view.

Kawasaki disease is a multisystemic vasculitis that can result in coronary artery lesions. It predominantly affects young children and is characterized by prolonged fever, diffuse mucosal inflammation, indurative oedema of the hands and feet, a polymorphous skin rash and non-suppurative lymphadenopathy. Coronary artery involvement is the most important complication of Kawasaki disease and may cause significant coronary stenosis resulting in ischemic heart disease. The introduction of intravenous immunoglobulin decreases the incidence of coronary artery lesions to less than 5%. The etiopathogenesis of this disease remains unclear. Several lines of evidence suggest that an interplay between a microbial infection and a genetic predisposition could take place in the development of the disease. In this review, we summarize the state of the art of pathogenetic mechanisms of Kawasaki disease underscoring the relevance of haematological features as a novel field of investigation.

Superior Mesenteric Artery Syndrome in Anorexia Nervosa: A Case Report and a Systematic Revision of the Literature.

BACKGROUND: Superior mesenteric artery syndrome (SMAS) is a rare condition caused by the compression of the duodenum, which may occur in the case of fast weight loss. Currently, the relationship between superior mesenteric artery syndrome and anorexia nervosa is still unclear. The aim of this study is to identify the precocious clinical signs and symptoms of SMAS in patients affected by anorexia nervosa so as not to delay the diagnosis. METHODS: We present the clinical case of a young female patient with anorexia nervosa complicated by SMAS. We performed a literature review of SMAS in children affected by anorexia nervosa between 1962 and 2023, according to the PRISMA Extension Guide for Scoping Reviews. RESULTS: Reviewing the literature, 11 clinical cases were described for the pediatric age. The median age at diagnosis was 17 years (ranging from 13 to 18 years). The diagnosis of SMAS may be challenging as symptoms overlap those of anorexia, but it should be kept in mind mostly in cases of post-prandial abdominal pain, anxiety or depression, nausea, vomiting, and weight loss. CONCLUSION: Even specific clinical symptoms may act as flag tags to drive attention to this rare but potentially fatal condition.

Paraneoplastic pemphigus and Castleman's disease: a case report and a revision of the literature.

BACKGROUND: In literature, a few reports described an association between paraneoplastic pemphigus (PNP) and Castelman's disease (CD), but no consensus have been proposed for the diagnostic-therapeutical approach. Aim of this study is to present a case report and explore the relationship between PNP and CD in pediatric patients, focusing on clinical manifestations, histopathological findings, treatment and outcome to find elements for an early diagnosis. CASE PRESENTATION: We present the clinical case of a 13 years old girl with a challenging diagnosis of PNP and CD who underwent therapy at first with Rituximab and then with Siltuximab, for the control of symptoms. CONCLUSIONS: Reviewing literature, 20 clinical cases have been described in the pediatric age. Diagnosis may be challenging, requiring an average of 3 months (range from 3 weeks to 2 years). In all cases, the initial manifestations were mucocutaneous lesions, especially oral lesions with poor response to conventional treatment. Systemic symptoms may be present as well. Therapeutical approach is still discussed with no consensus. Almost all patients received corticosteroids with poor response. Other drugs including azathioprine, methotrexate, cyclosporine and monoclonal antibodies have been evaluated for the control of the disease. Further studies and experimental trials urge to define the diagnostic criteria and therapy protocol.

Clinical characteristics of children infected with SARS-CoV-2 in Italy.

BACKGROUND: Since December 2019 coronavirus disease (COVID-19) emerged in Wuhan and spread rapidly worldwide. Despite the high number of people affected, data on clinical features and prognostic factors in children and adolescents are limited. We propose a retrospective study aimed to evaluate clinical characteristics of children infected with SARS-CoV-2 in Italy. METHODS: A pediatric population admitted with COVID-19 to Bambino Gesù Children's Hospital of Rome (Italy) in the period from the end of February to July 2020 has been studied. Medical history, comorbidities, symptoms and laboratory findings were obtained from patients' electronic medical records. RESULTS: In 66 patients (35 males and 31 females) we found that: i) fever and cough were the dominant symptoms, while vomit and convulsions were rare symptoms; and ii) all ages of childhood were susceptible to COVID-19. Furthermore, we found that, compared to females, males with COVID-19, although not significantly, had higher values of inflammatory markers such as C-reactive protein (CRP) and ESR. Conversely, we found that COVID-19 positive females were older than males and required more days of hospitalization. Both males and females COVID-19 positives had procalcitonin values within the normal range and D-Dimer values slightly higher than the normal range. With regard to this latter marker, the value measured in females, although not significant, was higher than that measured in males. Interestingly, the presence of leukopenia was found in both sexes. CONCLUSIONS: Compared to the adults we found that COVID-19 infection in children is a non-severe inflammatory disease in both males and females. In any case, many detailed studies should be conducted.

Childhood multisystem inflammatory syndrome associated with COVID-19 (MIS-C): a diagnostic and treatment guidance from the Rheumatology Study Group of the Italian Society of Pediatrics.

BACKGROUND: Italy was the first Western country to be hit by the SARS-CoV-2 epidemic. There is now mounting evidence that a minority of children infected with SARS-CoV2 may experience a severe multisystem inflammatory syndrome, called Multisystem inflammatory Syndrome associated with Coronavirus Disease 2019 (MIS-C). To date no universally agreed approach is available for this disease. MAIN BODY: as Italy is now facing a second hity of COVID-19 cases, we fear a recrudescence of MIS-C cases. We have, therefore, decided to prepare a report that will help clinicians to face this novel and challenging disease. We propose a diagnostic algorithm, to help case definition and guide work-up, and a therapeutic approach. MIS-C should be promptly recognized, based on the presence of systemic inflammation and specific organ involvement. Early treatment is crucial, and it will be based on the combined use of corticosteroids, high-dose immunoglobulins and anti-cytokine treatments, depending on the severity of the disease. Ancillary treatments (such as. aspirin and thrombo-profilaxis) will be also discussed. CONCLUSIONS: we propose a document that will help physicians to diagnose and treat MIS-C patients. Given the level of evidence available and the methodology used, this document should not be interpreted as a guideline; the final decision about the optimal management should still be taken by the caring physician, on an individual basis.

Revised recommendations of the Italian Society of Pediatrics about the general management of Kawasaki disease.

Aim of these revised recommendations for the general management of Kawasaki disease is to encourage its prompter recognition and warrant the most appropriate therapy, based on ascertained scientific data, raising awareness of the complications related to misdiagnosis or delayed treatment. A set of 20 synthetic operative statements is herein provided, including the definition of Kawasaki disease, its protean presentations, clinical course and seminal treatment modalities of all disease phases. The application of these recommendations should improve prognosis of Kawasaki disease and prevent the progression to permanent vascular abnormalities, thereby diminishing morbidity and mortality.

Defining Kawasaki disease and pediatric inflammatory multisystem syndrome-temporally associated to SARS-CoV-2 infection during SARS-CoV-2 epidemic in Italy: results from a national, multicenter survey.

BACKGROUND: There is mounting evidence on the existence of a Pediatric Inflammatory Multisystem Syndrome-temporally associated to SARS-CoV-2 infection (PIMS-TS), sharing similarities with Kawasaki Disease (KD). The main outcome of the study were to better characterize the clinical features and the treatment response of PIMS-TS and to explore its relationship with KD determining whether KD and PIMS are two distinct entities. METHODS: The Rheumatology Study Group of the Italian Pediatric Society launched a survey to enroll patients diagnosed with KD (Kawasaki Disease Group - KDG) or KD-like (Kawacovid Group - KCG) disease between February 1st 2020, and May 31st 2020. Demographic, clinical, laboratory data, treatment information, and patients' outcome were collected in an online anonymized database (RedCAP®). Relationship between clinical presentation and SARS-CoV-2 infection was also taken into account. Moreover, clinical characteristics of KDG during SARS-CoV-2 epidemic (KDG-CoV2) were compared to Kawasaki Disease patients (KDG-Historical) seen in three different Italian tertiary pediatric hospitals (Institute for Maternal and Child Health, IRCCS "Burlo Garofolo", Trieste; AOU Meyer, Florence; IRCCS Istituto Giannina Gaslini, Genoa) from January 1st 2000 to December 31st 2019. Chi square test or exact Fisher test and non-parametric Wilcoxon Mann-Whitney test were used to study differences between two groups. RESULTS: One-hundred-forty-nine cases were enrolled, (96 KDG and 53 KCG). KCG children were significantly older and presented more frequently from gastrointestinal and respiratory involvement. Cardiac involvement was more common in KCG, with 60,4% of patients with myocarditis. 37,8% of patients among KCG presented hypotension/non-cardiogenic shock. Coronary artery abnormalities (CAA) were more common in the KDG. The risk of ICU admission were higher in KCG. Lymphopenia, higher CRP levels, elevated ferritin and troponin-T characterized KCG. KDG received more frequently immunoglobulins (IVIG) and acetylsalicylic acid (ASA) (81,3% vs 66%; p = 0.04 and 71,9% vs 43,4%; p = 0.001 respectively) as KCG more often received glucocorticoids (56,6% vs 14,6%; p < 0.0001). SARS-CoV-2 assay more often resulted positive in KCG than in KDG (75,5% vs 20%; p < 0.0001). Short-term follow data showed minor complications. Comparing KDG with a KD-Historical Italian cohort (598 patients), no statistical difference was found in terms of clinical manifestations and laboratory data. CONCLUSION: Our study suggests that SARS-CoV-2 infection might determine two distinct inflammatory diseases in children: KD and PIMS-TS. Older age at onset and clinical peculiarities like the occurrence of myocarditis characterize this multi-inflammatory syndrome. Our patients had an optimal response to treatments and a good outcome, with few complications and no deaths.

Oxidative stress and defective platelet apoptosis in naïve patients with Kawasaki disease.

Kawasaki disease (KD) is a rare and often undiagnosed disease, at least in the western countries. It is characterized by an inflammatory acute febrile vasculitis of medium sized arteries with a propensity to damage the coronary arteries. It normally occurs in the early childhood and the diagnosis is based on clinical symptoms. During the progression of the disease thrombocytosis is usually detected. This can exert a pathogenetic role in the cardiovascular complications occurring in KD. In the present work peripheral blood plasma and platelets from twelve naïve patients with KD were analyzed in order to detect possible pathogenetic determinants or progression markers. Morphological, biochemical and flow cytometrical methods have been used. With respect to age-matched healthy donors, we found an increase of platelet activation markers, i.e. degranulation, phosphatidylserine (PS) externalization and leukocyte-red cell-platelet aggregates. Some significant alterations that could represent suitable diagnostic determinants have also been detected in patient plasma: (i) decreased antioxidant power, (ii) decreased levels of asymmetric dymethylarginine (ADMA), a naturally occurring chemical interfering with the production of nitric oxide, and (iii) increased levels of soluble P-Selectin and soluble annexin V. Since PS externalizing platelets are known to exert a pro-coagulant activity, our data suggest the hypothesis that increased risk of vascular complications in KD could depend on platelet stimulation and defective apoptosis probably related to nitrosative stress.

Scurvy: still a threat in the well-fed first world?

We report three cases of scurvy in previously healthy children referred to us for leg pain and refusal to walk. All children had no significant medical history, symptoms had started months before and subtly advanced. Two of them presented with gingival hyperplasia and petechiae, another one reported night sweats and gingival bleeding in the past few weeks. Two had vitamin D deficiency, and all had microcytic anaemia (in one case requiring transfusional support). A nutritional screening revealed low or undetectable levels of ascorbic acid. This, along with the clinical and radiological findings, led to a diagnosis of scurvy. Vitamin C supplementation was started with rapid improvement of the children's clinical condition. Scurvy is a rare disease in the 'first world', but there are anecdotal reports of scurvy in children without any of the known risk factors for this condition. In our cases, a selective diet was the only risk factor.

Laboratory Biomarkers to Facilitate Differential Diagnosis between Measles and Kawasaki Disease in a Pediatric Emergency Room: A Retrospective Study.

This retrospective study was conducted to analyze clinical and laboratoristic parameters to individuate specific differences and facilitate differential diagnosis between Measles and Kawasaki Disease (KD) at first evaluation in an emergency room. We found similar clinical features as duration of fever and number of KD criteria (p > 0.5) but significant differences in white blood cell count, neutrophils, CRP and LDH levels (p < 0.001). LDH value ≥ 800 mg/dl had sensibility of 89% and specificity of 90% for Measles while CRP ≥ 3 mg/dl had sensibility 89% and specificity of 85% for KD. The combined use of CRP, LDH and AST showed accuracy of 86.67%.

Vitamin K deficiency: a case report and review of current guidelines.

BACKGROUND: Vitamin K, a fat soluble vitamin, is a necessary cofactor for the activation of coagulation factors II, VII, IX, X, and protein C and S. In neonatal period, vitamin K deficiency may lead to Vitamin K Deficiency Bleeding (VKDB). CASE PRESENTATION: We present the case of a 2 months and 20 days Caucasian male, presented for bleeding from the injections sites of vaccines. At birth oral vitamin K prophylaxis was administered. Neonatal period was normal. He was exclusively breastfed and received a daily oral supplementation with 25 µg of vitamin K. A late onset vitamin K deficiency bleeding was suspected. Intravenous Vitamin K was administered with complete recovery. CONCLUSIONS: Nevertheless the oral prophylaxis, our case developed a VKDB: it is necessary to revise the current guidelines in order to standardize timing and dosage in different clinical conditions.

Kawasaki disease: guidelines of Italian Society of Pediatrics, part II - treatment of resistant forms and cardiovascular complications, follow-up, lifestyle and prevention of cardiovascular risks.

This second part of practical Guidelines related to Kawasaki disease (KD) has the goal of contributing to prompt diagnosis and most appropriate treatment of KD resistant forms and cardiovascular complications, including non-pharmacologic treatments, follow-up, lifestyle and prevention of cardiovascular risks in the long-term through a set of 17 recommendations.Guidelines, however, should not be considered a norm that limits the treatment options of pediatricians and practitioners, as treatment modalities other than those recommended may be required as a result of peculiar medical circumstances, patient's condition, and disease severity or individual complications.

Kawasaki disease: guidelines of the Italian Society of Pediatrics, part I - definition, epidemiology, etiopathogenesis, clinical expression and management of the acute phase.

The primary purpose of these practical guidelines related to Kawasaki disease (KD) is to contribute to prompt diagnosis and appropriate treatment on the basis of different specialists' contributions in the field. A set of 40 recommendations is provided, divided in two parts: the first describes the definition of KD, its epidemiology, etiopathogenetic hints, presentation, clinical course and general management, including treatment of the acute phase, through specific 23 recommendations.Their application is aimed at improving the rate of treatment with intravenous immunoglobulin and the overall potential development of coronary artery abnormalities in KD. Guidelines, however, should not be considered a norm that limits treatment options of pediatricians and practitioners, as treatment modalities other than those recommended may be required as a result of peculiar medical circumstances, patient's condition, and disease severity or complications.

Neuroprotective effects of anthocyanins and their in vivo metabolites in SH-SY5Y cells.

Recent in vivo studies have highlighted an important role for the neuroprotective actions of dietary anthocyanins. However, one consistent result of these studies is that the systemic bioavailability of anthocyanins, including cyanidin 3-O-glucopyranoside (Cy-3G), is very poor. Cy-3G has been demonstrated to be highly instable at physiological pH, so its in vivo metabolites, such as the aglycon cyanidin (Cy) and protocatechuic acid (PA), may be responsible for both the antioxidant activitiy and the neuroprotective effects observed in vivo. Therefore, we investigated the protective effects of Cy-3G, Cy and PA against H(2)O(2)-induced oxidative stress in a human neuronal cell line (SH-SY5Y). We determined their ability to counteract reactive oxygen species (ROS) formation and to inhibit apoptosis in terms of mitochondrial functioning loss and DNA fragmentation induced by H(2)O(2). We demonstrated that pretreatment of SH-SY5Y cells with Cy-3G, Cy and PA inhibits H(2)O(2)-induced ROS formation at different cellular levels: Cy-3G at membrane level, PA at cytosolic level and Cy at both membrane and cytosolic levels. In addition, Cy showed a higher antioxidant activity at membrane and cytosolic level than Cy-3G and PA, respectively. Interestingly, both Cy and PA, but not Cy-3G, could inhibit H(2)O(2)-induced apoptotic events, such as mitochondrial functioning loss and DNA fragmentation. These results suggest that Cy and PA may be considered as neuroprotective molecules and may play an important role in brain health promotion. These in vitro findings should encourage further research in animal models of neurological diseases to explore the potential neuroprotective effects of compounds generated during in vivo metabolism of anthocyanins.

Protective effects of cyanidin-3-O-beta-glucopyranoside against UVA-induced oxidative stress in human keratinocytes.

Ultraviolet-A (UVA) radiation causes significant oxidative stress because it leads to the generation of reactive oxygen species (ROS), leading to extensive cellular damage and eventual cell death either by apoptosis or necrosis. We evaluated the protective effects of cyanidin-3-O-beta-glucopyranoside (C-3-G) against UVA-induced apoptosis and DNA fragmentation in a human keratinocyte cell line (HaCaT). Treatment of HaCaT cells with C-3-G before UVA irradiation inhibited the formation of apoptotic cells (61%) and DNA fragmentation (54%). We also investigated antioxidant properties of C-3-G in HaCaT cells against ROS formation at apoptotic doses of UVA; C-3-G inhibited hydrogen peroxide (H2O2) release (an indicator of cellular ROS formation) after UVA irradiation. Further confirmation of the potential of C-3-G to counteract UVA-induced ROS formation comes from our demonstration of its ability to enhance the resistance of HaCaT cells to the apoptotic effects of both H2O2 and the superoxide anion (O2*-), two ROS involved in UVA-oxidative stress. Furthermore, in terms of Trolox Equivalent Antioxidant Activity, C-3-G treatment led to a greater increase in antioxidant activity in the membrane-enriched fraction than in the cytosol (55% vs 19%). The protective effects against UVA-induced ROS formation can be attributed to the higher membrane levels of C-3-G incorporation. These encouraging in vitro results support further research into C-3-G (and other anthocyanins) as novel agents for skin photoprotection.

Follow-up of infants exposed to hydroxychloroquine given to mothers during pregnancy and lactation.

OBJECTIVE: To determine the effect of hydroxychloroquine treatment during pregnancy and lactation on babies of mothers affected by rheumatic diseases. STUDY DESIGN AND METHODS: A total of 40 infants born from mothers affected by rheumatic diseases and treated with hydroxychloroquine during pregnancy were enrolled in a prospective observational study. Main outcome measures at birth were incidence of prematurity, congenital malformations and neonatal infections. Of these babies, including 13 who were breast-fed, 24 were followed up during early infancy for visual function and neurodevelopmental outcome. RESULTS: Preterm delivery was the main complication (20.5%). No significant congenital malformations or neonatal infections were detected. All infants, including those who were breast-fed, had normal visual function and neurodevelopmental outcome. CONCLUSIONS: Hydroxychloroquine treatment during gestation and lactation appeared to be safe. The relatively high incidence of preterm deliveries may reflect the maternal disease state.

Linezolid therapy in a perinatal late-onset Staphylococcus aureus sepsis complicated by spondylodiscitis and endophthalmitis.

We report the case of a two-month-old immunocompetent girl affected by Staphylococcus aureus sepsis complicated with pneumonia and pleural effusion, spondylodiscitis and endophthalmitis treated with linezolid. She developed a S. aureus sepsis in the neonatal period antibiotically treated with clinical resolution. Ten days after therapy discontinuation, the infant experienced a new S. aureus sepsis complicated by pneumonia with pleural effusion. Due to the presence of dorsal swelling, a pulmonary computer tomography was performed that showed a dorsal D5-D6 spondylodiscitis. Since the sepsis was scarcely responsive to several appropriate antibiotics, we finally decided to treat the patient with linezolid. A few weeks after changing antibiotics, the child underwent an ophthalmologic visit. Due to the finding of ocular lesions, imaging examinations were performed. The diagnosis was compatible with retinoblastoma, such that the eye was enucleated. Nevertheless, histological and microbiological investigations did not confirm the tumour hypothesis, but revealed a S. aureus abscess with retinal detachment. The child completed antibiotic therapy with linezolid and was visited periodically at the Infectious Disease Unit for a follow-up. She underwent progressive resolution of discitis and did not present any further flare of sepsis. Nevertheless, she still has a replacement device in her right eye and a D5-D6 severe kyphosis with spinal fusion.