The elevated markers of hypercoagulability in children with Henoch-Schönlein purpura

Predicting renal damage in children with IgA vasculitis by machine learning

BACKGROUND

Children with IgA Vasculitis (IgAV) may develop renal complications, which can impact their long-term prognosis. This study aimed to build a machine learning model to predict renal damage in children with IgAV and analyze risk factors for IgA Vasculitis with Nephritis (IgAVN).

METHODS

50 clinical indicators were collected from 217 inpatients at our hospital. Six machine learning algorithms-Logistic Regression, Linear Discriminant Analysis, K-Nearest Neighbor, Support Vector Machine, Decision Trees, and Random Forest-were utilized to select the model with the highest predictive performance. A simplified model was developed through feature importance ranking and validated by an additional cohort with 46 patients.

RESULTS

The random forest model had the highest accuracy, precision, recall, F1 score, and area under the curve, with values of 0.91, 0.98, 0.70, 0.79 and 0.94, respectively. The top 11 features according to the importance ranking were anti-streptolysin O, corticosteroids therapy, antihistamine therapy, absolute eosinophil count, immunoglobulin E, anticoagulant therapy, C-reactive protein, prothrombin time, age at onset, D-dimer, recurrence of rash ≥ 3 times. A simplified model using these features demonstrated optimal performance with an accuracy of 84.2%, a sensitivity of 89.4%, and a specificity of 82.5% in external validation. Finally, we provided a web tool based on the simplified model, whose code was published on https://github.com/mulanruo/IgAVN_Prediction .

CONCLUSION

The model based on the random forest algorithm demonstrates good performance in predicting renal damage in children with IgAV, providing a basis for early clinical diagnosis and decision-making.

Clinical characteristics and risk factors of cardiac involvement in pediatric immunoglobulin A vasculitis: A 7-year retrospective study from a single tertiary medical center

Immunoglobulin A vasculitis(IgAV) is the most common form of systemic vasculitis affecting children. To date, cardiac involvement in pediatric IgAV has not been fully investigated and its prevalence may be underestimated. This study aims to reveal the clinical and laboratory characteristics of cardiac involvement in pediatric IgAV and further determine its risk factors. A total of 1451 children with IgAV were recruited between January 2016 and December 2022. According to the severity of cardiac involvement, the patients were divided into the myocarditis/suspected myocarditis group, cardiac abnormalities group, and non-cardiac involvement group. Demographic, clinical, and laboratory characteristics were retrospectively extracted from the individual data collected in the medical records. Among the 1451 pediatric IgAV patients, 179 (12.3%) were identified with cardiac involvement, including 154 (10.6%) with cardiac abnormalities and 25 (1.7%) with myocarditis/suspected myocarditis. Cardiac involvement in pediatric IgAV mainly manifested as elevated cardiac biomarker levels (n = 162), electrocardiogram abnormalities (n = 46), and echocardiogram/chest X-ray abnormalities (n = 15); however, cardiac-related symptoms were only observed in 15.1% of patients with cardiac involvement. Multivariate analysis demonstrated that interval from disease onset to diagnosis > 7 days (OR, 2.157; 95% CI, 1.523-3.057; p < 0.001), IgAV with multi-organ involvement (OR, 1.806; 95% CI, 1.242-2.627; p = 0.002), and elevated D-dimer levels (OR, 1.939; 95% CI, 1.259-2.985; p < 0.001) were independent risk factors for cardiac involvement in pediatric IgAV. The length of hospital stay was significantly longer in the myocarditis/suspected myocarditis group compared with the other two groups (p < 0.05).     Conclusion: This study suggests that cardiac involvements in pediatric IgAV is non-negligible, and cardiac involvement is associated with interval from disease onset to diagnosis > 7 days, IgAV with multi-organ involvement, and elevated D-dimer levels. Severe cardiac involvement may affect the prognosis of pediatric IgAV. What is Known: • Immunoglobulin A vasculitis (IgAV) is the most common form of systemic vasculitis affecting children and adolescents, which exhibits diverse clinical manifestations. Cases of severe IgAV complicated by cardiac involvement have been anecdotally reported. What is New: • The present study suggests that cardiac involvements in pediatric IgAV is non-negligible, and cardiac involvement is associated with interval from disease onset to diagnosis > 7 days, IgAV with multi-organ involvement, and elevated D-dimer levels. Severe cardiac involvement may affect the prognosis of pediatric IgAV.

Clinical characteristics and risk factors of IgA vasculitis with intussusception and intestinal perforation

AIM

Intussusception is the most common surgical complication of IgA vasculitis (IgAV), and intestinal perforation is usually associated with intussusception. If they are not recognised and treated in a timely manner, serious consequences may occur. The objective is to summarise the clinical features of IgAV complicated by intussusception and intestinal perforation and explore its risk factors.

METHODS

The clinical data of 32 patients with IgAV complicated by surgical complications (25 cases of intussusception and 7 cases of intestinal perforation) were retrospectively analysed. A total of 160 IgAV children with gastrointestinal (GI) involvement but without surgical complications were randomly selected as a control group. Binary logistic regression analysis was performed to explore the risk factors for IgAV with intussusception and intestinal perforation.

RESULTS

Compared with the intussusception group, the intestinal perforation group had a significantly higher number of patients with GI symptoms prior to skin purpura and GI bleeding, a significantly higher number of days of abdominal pain, a significantly higher Wong-Baker score, and a significantly higher white blood cell count. Multivariate logistic regression analysis indicated that age ≤7 years, GI symptoms prior to skin purpura, abdominal pain intensity (Wong-Baker scale) and timing of glucocorticoid treatment were independent risk factors of IgAV with intussusception and intestinal perforation.

CONCLUSION

Age less than 7 years, severe abdominal pain, and GI symptoms prior to skin purpura were risk factors for IgAV with intussusception and intestinal perforation. Early use of glucocorticoids may prevent intussusception and intestinal perforation.

A simple nomogram for assessing the risk of IgA vasculitis nephritis in IgA vasculitis Asian pediatric patients

A nomogram for assessing the risk of IgA vasculitis nephritis (originally termed Henoch–Schönlein purpura nephritis, HSPN) in IgA vasculitis (originally termed Henoch–Schönlein purpura, HSP) pediatric patients can effectively improve early diagnosis and prognosis of IgA vasculitis nephritis. However, currently, no nomogram is available. 246 IgA vasculitis and 142 IgA vasculitis nephritis Asian pediatric patients confirmed by renal biopsy were enrolled. Univariate and multivariate logistic regressions were performed to identify the independent risk factors and construct a series of predictive models. The receiver operating characteristic curve, calibration plot, decision curve analysis, net reclassification index and integrated discrimination index were used to screen the best model. Stratification analysis was applied to optimize model’s clinical utility. An external validation set was introduced to verify the predictive efficiency. The final predictive model was converted to nomogram for visual use. We identified age, duration of rash (Dor), D-dimer and IgG as independent risk factors and constructed four models as follows: AIDD (Age + IgG + Dor + D-dimer), AIDi (Age + IgG + D-dimer), AIDo (Age + IgG + Dor) and ADD (Age + Dor + D-dimer), which achieved the receiver operator characteristic curve (AUROC) of 0.931, 0.920, 0.856 and 0.907, respectively. Finally, AIDi model with an AUROC of 0.956 and 0.897 in internal and external validating sets was proposed as a novel predictive model. In stratification analysis by gender and histological grade, the AUROC of AIDi was 0.949 in female, 0.926 in male, 0.933 in mild histological grades and 0.939 in severe histological grades, respectively. AIDi nomogram is an effective and visual tool for assessing the risk of nephritis in IgA vasculitis Asian pediatric patients, regardless of IgA vasculitis nephritis histological grades and gender.

Predictive Value of Laboratory Indexes on Renal Involvement in Children with Henoch-Schönlein Purpura

Objective

Henoch-Schönlein purpura (HSP) is the most common vasculitis in children. Renal involvement is the main long-term complication of HSP, and presently there is no way to predict which children may have irreversible renal damage from the outset. This study aimed to explore the prediction value of laboratory indexes on renal involvement in children with HSP, which could help the early identification and intervention.

Methods

Children with HSP hospitalized at the First Affiliated Hospital of Henan University of Chinese Medicine from June 2019 to December 2020 were included. The demographic findings, clinical features, laboratory findings including blood routine examination, serum immunoglobulin, complement, T cell subsets levels, liver and kidney function, coagulation function were recorded. Laboratory indexes were analyzed, logistic regression analysis was performed to identify the independent predictors in HSP patients with renal involvement, and receiver operating characteristic (ROC) curves were further used to assess the value of prediction indexes, as well as the efficacy of combined diagnosis.

Results

The study included 146 HSP patients, among them, 50 patients (34.2%) had renal involvement. Age, platelet distribution width (PDW), CD3⁺ and fibrinogen (FIB) were positively correlated with renal involvement, while the levels of Immunoglobulin G (IgG), C-reactive protein (CRP), and neutrophil/lymphocyte ratio (NLR) were negatively correlated with renal involvement. The area under the ROC Curve (AUC) of these biomarkers ranged from 0.6284 to 0.7009, and among the combinations, a combination of NLR, CRP, CD3⁺, FIB, PDW, IgG and age had the best AUC value (0.9774).

Conclusion

Age, PDW, CD3⁺, FIB, CRP, NLR and IgG were prediction indexes for renal involvement in HSP patients, and these indexes can be combined appropriately to improve the diagnostic efficacy.

Risk factors for intussusception in children with Henoch-Schönlein purpura: A case-control study

BACKGROUND

The etiology of Henoch-Schönlein purpura (HSP) with intussusception remains undefined.

AIM

To investigate the risk factors for intussusception in children with HSP and gastrointestinal (GI) involvement.

METHODS

Sixty children with HSP and concomitant intussusception admitted to the Beijing Children’s Hospital of Capital Medical University between January 2006 and December 2018 were enrolled in this study. One hundred pediatric patients with HSP and GI involvement but without intussusception, admitted to the same hospital during the same period, were randomly selected as a control group. The baseline clinical characteristics of all patients, including sex, age of onset, duration of disease, clinical manifestations, laboratory test results, and treatments provided, were assessed. Univariate and multiple logistic regression analyses were performed to identify possible risk factors.

RESULTS

The 60 children in the intussusception group comprised 27 girls (45%) and 33 boys (55%) and the 100 children in the non-intussusception group comprised 62 girls (62%) and 38 boys (38%). The median age of all patients were 6 years and 5 mo. Univariate and multiple regression analyses revealed age at onset, not receiving glucocorticoid therapy within 72 h of emergence of GI symptoms, hematochezia, and D-dimer levels as independent risk factors for intussusception in children with HSP (P < 0.05).

CONCLUSION

The four independent risk factors for intussusception in pediatric HSP with GI involvement would be a reference for early prevention and treatment of this potentially fatal disease.

Gastrointestinal involvement and its association with the risk for nephritis in IgA vasculitis

Background:

We analysed clinical and biochemical parameters in predicting severe gastrointestinal (GI) manifestations in childhood IgA vasculitis (IgAV) and the risk of developing renal complications.

Methods:

A national multicentric retrospective study included children with IgAV reviewed in five Croatian University Centres for paediatric rheumatology in the period 2009–2019.

Results:

Out of 611 children, 281 (45.99%) had at least one GI manifestation, while 42 of 281 (14.95%) had the most severe GI manifestations. Using logistic regression several clinical risk factors for the severe GI manifestations were identified: generalized rash [odds ratio (OR) 2.09 (95% confidence interval (CI) 1.09–4.01)], rash extended on upper extremities (OR 2.77 (95% CI 1.43–5.34)] or face [OR 3.69 (95% CI 1.42–9.43)] and nephritis (IgAVN) [OR 4.35 (95% CI 2.23–8.50)], as well as lower values of prothrombin time (OR 0.05 (95% CI 0.01–0.62)], fibrinogen [OR 0.45 (95% CI 0.29–0.70)] and IgM [OR 0.10 (95% I 0.03–0.35)]] among the laboratory parameters. Patients with severe GI involvement more frequently had relapse of the disease [OR 2.14 (CI 1.04–4.39)] and recurrent rash [OR 2.61 (CI 1.27–5.38)]. Multivariate logistic regression found that the combination of age, GI symptoms at the beginning of IgAV and severity of GI symptoms were statistically significant predictors of IgAVN. Patients in whom IgAV has started with GI symptoms [OR 6.60 (95% CI 1.67–26.06)], older children [OR 1.22 (95% CI 1.02–1.46)] with severe GI form of IgAV (OR 5.90 (95% CI 1.12–31.15)] were particularly high-risk for developing IgAVN.

Conclusion:

We detected a group of older children with the onset of GI symptoms before other IgAV symptoms and severe GI form of the IgAV, with significantly higher risk for acute and chronic complications of IgAV.

A Child with COVID-19 and Immunoglobulin A Vasculitis

We describe the case of a child with progressive abdominal pain and rash admitted to a large tertiary children's hospital in the Chicago metropolitan area and subsequently found to have immunoglobulin A (IgA) vasculitis and coronavirus disease 2019 (COVID-19). This patient presented with abdominal pain, purpuric lesions, hematochezia, increasingly elevated D-dimer, and abnormal inflammatory markers on laboratory evaluation. To the best of our knowledge, this article describes the only reported pediatric case of COVID-19 associated with IgA vasculitis. [Pediatr Ann. 2021;50(1):e44-e48.].

Fecal calprotectin as a marker of gastrointestinal involvement in pediatric Henoch-Schönlein purpura patients: a retrospective analysis

Background

Henoch–Schönlein purpura is a type of systemic vasculitis found in children. Its prognosis is usually good; however, recurrence is relatively common. If the intestines are affected, severe complications could arise. Here, we investigated the value of fecal calprotectin in the early screening of Henoch–Schönlein purpura and as a useful factor for predicting gastrointestinal manifestations.

Methods

We retrospectively reviewed the medical records of pediatric patients who were diagnosed with Henoch–Schönlein purpura and underwent fecal calprotectin testing during the acute phase. The patients were categorized into gastrointestinal involvement and non-gastrointestinal involvement groups based on their clinical symptoms. Moreover, gastrointestinal involvement was categorized as follows: upper gastrointestinal tract involvement (up to the duodenum) and lower gastrointestinal tract involvement (from the terminal ileum).

Results

A total of 69 patients were diagnosed with Henoch–Schönlein purpura and underwent fecal calprotectin testing. Among them, 40 patients (58.0%) showed signs of gastrointestinal involvement. The gastrointestinal involvement group had higher fecal calprotectin levels (379.9 ± 399.8 vs. 77.4 ± 97.6 mg/kg, P = 0.000). There were no significant differences in the recurrence of Henoch–Schönlein purpura symptoms or gastrointestinal symptoms. The cut-off value to identify gastrointestinal involvement was 69.10 mg/kg (P < 0.01). Patients with fecal calprotectin levels of > 50 mg/kg showed more frequent gastrointestinal involvement (77.8% vs. 20.8%, P = 0.000) and more severe gastrointestinal symptoms. Significant differences in abdominal pain duration, Henoch–Schönlein purpura clinical score, and abdominal pain severity were observed (P = 0.002, P = 0.000, and P = 0.000, respectively). Additionally, fecal calprotectin levels were significantly higher in patients with lower gastrointestinal tract involvement (214.67 ± 150.5 vs. 581.8 ± 510.1 mg/kg, P = 0.008), and the cut-off value was 277.5 mg/kg (P < 0.01).

Conclusion

Fecal calprotectin testing is useful for identifying gastrointestinal involvement in pediatric Henoch–Schönlein purpura patients.

Colonoscopic diagnosis and reduction of recurrent intussusception owing to Henoch-Schönlein purpura without purpura

About 50-75% of patients with Henoch-Schönlein purpura (HSP) develop gastro-intestinal symptoms with surgical complications such as intussusception occurring in 0.7-13.6%. In 10-40% of patients, however, gastro-intestinal manifestations may precede the onset of purpura. In patients with gastro-intestinal tract involvement without purpura, confirming the diagnosis of HSP and determining the appropriate treatment remains difficult. A seven-year-old boy presented with recurrent intussusception owing to HSP without purpura. It was confirmed pathologically and treated via colonoscopy. Early colonoscopic intervention can contribute to the early diagnosis of HSP and its subsequent management by avoiding unnecessary surgical invasion.

Altered mean platelet volume in children with Henoch-Schonlein purpura and its association with disease activity

Background

Henoch-Schonlein purpura is a systemic small-vessel vasculitis that occurs mainly in children. A review of the literature has suggested a correlation between mean platelet volume and several inflammatory disorders. However, to the best of our knowledge, any potential correlation between mean platelet volume and Henoch-Schonlein purpura has not been reported in the literature. Therefore, our study aimed to evaluate the role of mean platelet volume concentrations in patients with Henoch-Schonlein purpura.

Methods

This study included 97 children with Henoch-Schonlein purpura and 120 healthy individuals as controls.

Results

Mean platelet volume concentrations were found to be significantly lower in Henoch-Schonlein purpura patients compared with healthy controls (8.1 ± 0.86 vs. 9.4 ± 0.81, P < 0.001). Similarly, significant negative correlations were observed between mean platelet volume and neutrophil count, platelet count and erythrocyte sedimentation rate in patients with Henoch-Schonlein purpura (r=−0.327, P = 0.001; r=−0.419, P < 0.001; r=−0.255, P = 0.012). Interestingly, mean platelet volume was significantly lower in the acute phase compared with the convalescent phase of Henoch-Schonlein purpura patients (7.8 ± 0.86 vs. 8.3 ± 0.77, P = 0.002). A cut-off value for mean platelet volume was 7.85 with area under the curve of 0.726 to identify acute phase vs. convalescent phase in patients with Henoch-Schonlein purpura. Mean platelet volume was independently associated with Henoch-Schonlein purpura in logistic regression analysis (odds ratio = 0.114, 95% confidence interval = 0.053–0.243, P < 0.001).

Conclusions

Our results suggest that mean platelet volume is inversely associated with disease in patients with Henoch-Schonlein purpura, and mean platelet volume may be a useful marker to identify active disease in Henoch-Schonlein purpura patients.

Henoch-Schönlein purpura with joint involvement: Analysis of 71 cases

BACKGROUND

Although joint involvement is the second most common clinical manifestation after skin involvement in patients with Henoch-Schönlein purpura (HSP), it has not been well characterized. The aim of this study was to profile the clinical characteristics and identify the potential risk factors for kidney damage in HSP patients having joint involvement.

METHODS

We retrospectively reviewed 71 cases of HSP patients with joint involvement who attended our hospital between January 2010 and March 2012 and analyzed their epidemiological profile, clinical characteristics, follow-up findings (up to three years) and overall prognosis. Logistic regression analysis was performed to identify risk factors associated with renal symptoms in HSP patients with joint involvement.

RESULTS

Average age of patients was 8.55 ± 2.13 years with male to female ratio at 1.29:1. The peak age of disease onset was six to 11 years. The most common triggers included upper respiratory infection, vigorous physical activity, and autumn and winter seasons. Forty cases (56.35 %) had gastrointestinal involvement and 37 (52.11 %) had kidney damage; gastrointestinal system, scrotal involvement, and increased D-dimer levels were significantly associated with kidney injury (P < 0.05) by multivariate analysis. Glucocorticoid therapy was effective in alleviating symptoms.

CONCLUSION

Gastrointestinal symptoms, scrotal involvement, and increased D-dimer are the potential risk factors for kidney damage in HSP patients having joint involvement. Rational use of corticosteroids was probably responsible for the good clinical outcomes.

An analysis of the levels of the soluble form of the endothelial protein C receptor in children with Henoch-Schönlein Purpura

The pathogenesis of Henoch-Schönlein Purpura (HSP) has not been clearly defined. Inflammatory cytokines have been associated with HSP but there are only a few reports that have focused on coagulation. The endothelial protein C receptor (EPCR), which has anticoagulant and antiinflammatory activity, is the key component of the protein C pathway. Recent studies have implicated the soluble form of EPCR (sEPCR) in Wegener's granulomatosis, Behçet's disease, and systemic lupus erythematosus. The aim of this study was to evaluate the levels of sEPCR in HSP children. Twenty-two children with HSP and 17 healthy children were included. We found no significant differences (P > .05) between patient and control groups in the levels of von Willebrand factor and thrombomodulin. The median sEPCR values in the HSP group were lower than the control group (79 vs. 102 ng/mL, respectively) (P > .05). The mean sEPCR value in HSP patients with severe abdominal pain was lower than without (88.8 ± 54.9 vs. 108.2 ± 66.3 ng/mL, respectively) (P > .05). In addition, the mean IL-6 serum levels were significantly elevated in HSP patients during the acute stage of HSP (2.1 ± 1.7 vs. 1.5 ± 1.2 pg/mL, P = .038). We also observed a slight negative correlation between the levels of sEPCR and IL-6 (R = -.135, P > .05). To our knowledge, this was the first study to analyze sEPCR levels in HSP. Our results did not conclusively identify a direct role of sEPCR in HSP, but our findings warrant further investigations, especially in severe HSP cases characterized by gastrointestinal bleeding or renal involvement.

Laboratory markers indicating gastrointestinal involvement of henoch-schönlein purpura in children

PURPOSE

To determine clinically useful biochemical markers reflecting disease activity and/or gastrointestinal (GI) tract involvement in Henoch-Schönlein purpura (HSP).

METHODS

A total of 185 children with HSP and 130 controls were included. Laboratory data indicating inflammation, standard coagulation, and activated coagulation were analyzed for the HSP patients, including measurements of the hemoglobin level, white blood cell (WBC) count, absolute neutrophil count (ANC), platelet count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, prothrombin time, activated partial thromboplastin time, and fibrinogen, D-dimer, and fibrin degradation product (FDP) levels. The clinical scores of the skin, joints, abdomen, and kidneys were assessed during the acute and convalescence phases of HSP.

RESULTS

The WBC count, ANC, ESR, and CRP, fibrinogen, D-dimer, and FDP levels were significantly higher in the acute phase compared with the convalescent phase of HSP (p<0.05). The total clinical scores were more strongly correlated with the D-dimer (r=0.371, p<0.001) and FDP (r=0.369, p<0.001) levels than with inflammatory markers, such as the WBC count (r=0.241, p=0.001), ANC (r=0.261, p<0.001), and CRP (r=0.260, p<0.001) levels. The patients with GI symptoms had significantly higher ANC (median [interquartile range], 7,138.0 [4,446.4-9,470.0] vs. 5,534.1 [3,263.0-8,153.5], p<0.05) and CRP (0.49 [0.15-1.38] vs. 0.23 [0.01-0.67], p<0.05), D-dimer (2.63 [1.20-4.09] vs. 1.75 [0.62-3.39]), and FDP (7.10 [0.01-13.65] vs. 0.10 [0.01-7.90], p<0.05) levels than those without GI symptoms.

CONCLUSION

D-dimer and FDPs are more strongly associated with disease activity and more consistently reflect GI involvement than inflammatory markers during the acute phase of HSP.

Advances in our understanding of the pathogenesis of Henoch-Schönlein purpura and the implications for improving its diagnosis

Henoch-Schönlein purpura (HSP) is a leukocytoclastic vasculitis classically characterized by palpable purpura, arthritis, abdominal pain and renal disease. In this article, we summarize our current understanding of the pathogenesis of HSP and the implications for improving its diagnosis. Although the pathogenesis of HSP is not fully understood yet, exciting new information has emerged in recent years, leading to a better understanding of its pathogenesis. Here, we discuss genetic predisposition, immunoglobulins with a particular emphasis on IgA1, activated complements, cytokines and chemokines, abnormal coagulation and autoantibodies in the underlying pathogenic mechanisms. Finally, diagnostic criteria for HSP developed by institutions such as the American College of Rheumatology and the European League against Rheumatism/Paediatric Rheumatology European Society were proposed to improve early detection and diagnosis.

Construction of a scoring system for predicting the risk of severe gastrointestinal involvement in Henoch-Schönlein Purpura

Objective

To evaluate the parameters associated with significant gastrointestinal (GI) involvement in Henoch-Schönlein Purpura (HSP), and construct a scoring system for the identification of patients at high risk of gross blood in stools.

Study design

Data for HSP patients hospitalized at each of seven institutes were retrospectively analyzed. Patients were divided into four groups according to the consequent severity of GI involvement. Identification of laboratory parameters at the time of admission were then used to differentiate the groups, and a scoring system to predict gross intestinal bleeding was constructed. Prognostic efficiency, correlation with the subsequent duration of abdominal pain, and association with manifestations excluding abdominal pain were also analyzed.

Results

An analysis of variance (ANOVA) test showed significant intergroup differences in white blood cell (WBC) count, neutrophil count, serum albumin, potassium, plasma D-dimer and coagulation factor XIII activity. A scoring system consisting of these parameters showed a good prognostic value for gross intestinal bleeding in a receiver operating characteristic (ROC) analysis, and a cut-off value of 4 points showed a sensitivity of 90.0% and specificity of 80.6%. The score was also correlated with the duration of abdominal pain after admission. A significantly higher score (s) was observed in patients presenting with nephritis, although the predictive value was poor.

Conclusion

A scoring system consisting of generally available parameters was of use in predicting severe GI involvement in HSP patients. Although further study is needed, initial therapy in accordance with disease activity may be taken into consideration using this scoring system.

Superior mesenteric artery syndrome: risk factor for duodenal involvement in Henoch-Schönlein purpura

BACKGROUND

The anatomical location of the third portion of the duodenum is between the superior mesenteric artery (SMA) and the abdominal aorta (AA). When the aorto-mesenteric angle (AMA) is small and the aorto-mesenteric distance (AMD) is short, the duodenum becomes tightly compressed between these two blood vessels. Severe compression can obstruct the duodenum, resulting in vomiting and abdominal pain. This clinical condition is termed superior mesenteric artery syndrome (SMA syndrome). The duodenum is frequently affected in Henoch-Schönlein purpura (HSP). The aim of the present study was to verify that duodenal anatomy mimicking SMA syndrome is a risk factor for duodenal involvement and abdominal pain in HSP.

METHODS

A prospective case-control study involving 12 HSP patients compared with 48 age- and sex-matched children (controls) was conducted. Bowel abnormalities were defined as thickened wall >3 mm and paralytic ileus detected on ultrasound. AMA, AMD and obesity index (OI) were compared between the two groups on Mann-Whitney testing. The correlation between duodenal bowel abnormalities and SMA syndrome was examined using Fisher's exact test.

RESULTS

AMA, AMD and OI were significantly smaller in the HSP patients (P < 0.001, 0.003 and 0.026, respectively). All HSP patients, but only 10 controls, met the ultrasound diagnostic criteria for SMA syndrome (100% vs 20.8%, P < 0.001).

CONCLUSIONS

Duodenal compression by SMA against the AA, which mimics SMA syndrome, may lead to duodenal bowel abnormalities with abdominal pain in thin children with HSP.

Clinical probability score and D-dimer estimation lack utility in the diagnosis of childhood pulmonary embolism

BACKGROUND

Childhood pulmonary embolism (PE) causes significant mortality and evidence suggests that it is under-diagnosed. Clinical probability scores and D-dimer estimation to assess pre-test probability have not been studied in children with suspected PE.

PATIENTS/METHODS

This retrospective cohort study evaluated Wells simplified probability score for PE in 50 children with PE and 25 PE negative control patients, and D-dimer values in 27 PE positive and 12 PE negative children.

RESULTS

PE positive and PE negative groups had similar rates of risk factors for venous thromboembolism (VTE). Wells simplified probability score showed a small difference between PE positive and PE negative children (median score: PE positive, 4.5; PE negative, 4; P = 0.009), children with PE are more likely to obtain a 'PE likely' score (score > 4), P = 0.012. The difference was of slightly greater significance when the Wells score was adjusted to account for pediatric normal ranges for heart rate, P = 0.007, and signs/symptoms of upper limb DVT, P = 0.006. Children with PE were as likely as PE negative patients to have a D-dimer value within the normal range (PE positive, 15%; PE negative, 25%; P = 0.654). A combination of a 'PE unlikely' score and normal D-dimer value occurred in 1/12 (8%) of PE negative children.

CONCLUSIONS

The Wells clinical probability score and D-dimer estimation may lack utility in the determination of pre-test probability of PE in children. Validation of a pediatric clinical probability score, incorporating D-dimer estimation, by prospective study, would be difficult as a result of the rarity of childhood PE.