Kawarabi: Administrative Structuring of a Multicenter Research Collaborative to Study Kawasaki Disease in the Arab Countries

Kawasaki disease (KD), the leading cause of acquired heart disease in children in developed countries, merits conducting detailed studies in Arab countries. We introduce Kawarabi, as a multicenter research collaborative effort dedicated to improving diagnosis, care, and outcome of children and adults with KD in the Arab world. During the COVID-19 pandemic, there emerged a new multisystem inflammatory syndrome in children; a disease similar to KD. This highlighted the challenges that Arab physicians face in diagnosing and managing children with KD and KD-like illnesses. Kawarabi brings together experts in North America and Arab nations to study this family of diseases in a not-for-profit, voluntary scientific collaborative setting. Bylaws addressing the vision, objectives, structure, and governance of Kawarabi were established, and vetted by the 45 organizing members in 2021. An initial scientific publication showed evidence of a decreased level of awareness of the disease in the general population, as well as the lack of access to resources available for physicians caring for children with KD in Arab countries. Kawarabi has since held several educational webinars and an inaugural yearly meeting. The groundwork for future initiatives targeted at increasing awareness and understanding of the management and the long-term outcomes of children with KD in the region was established. Data on KD in the Arab world are lacking. Kawarabi is a multicenter research collaborative organization that has the unique resources, diversified ethnic makeup, and energy, to accomplish significant advances in our understanding and management of KD and its variants.

Access to Care and Therapy for Kawasaki Disease in the Arab Countries: A Kawasaki Disease Arab Initiative (Kawarabi) Multicenter Survey

Kawasaki Disease (KD) is still the most common acquired heart disease in children below the age of five years; it has been well described in the developed world; however, data from the Arab world are limited to case reports or single-center case series. In an effort of optimizing KD research in the Arab world, a group of physicians and researchers established the KD Arab Initiative (Kawarabi) in 2021, and published the first survey, which showed disparities in the availability of intravenous immunoglobulin (IVIG); this had prompted Kawarabi to assess the access to care and therapy of KD patients in Arab countries. A 32 structured questions survey was conducted in thirteen Arab countries and addressed KD patients' access to healthcare in urban and rural settings. The survey results showed that access to care was uniform across large, mid-size cities and rural areas in 7/13 (54%) countries, while in 6/13 (46%) countries, it was in favor of large and mid-size cities over rural areas. The quality of medical services received by children with KD in large cities was rated as excellent in 6/13 or good in 7/13 countries compared to fair in 4/13 or poor in 4/13 countries in rural areas. Availability of IVIG was limited (23%) in mid-size cities and almost impossible (23%) in rural areas. The KD patients in mid-size cities and rural areas have limited access to standard healthcare in the Arab world. This survey laid the foundation for future Kawarabi endeavors to improve the care of children with KD.

The "Golden Hours" Algorithm For the Management of the Multisystem Inflammatory Syndrome in Children (MIS-C)

The global concern of increasing number of children presenting with multisystem inflammatory syndrome in children (MIS-C) related to the coronavirus disease (COVID-19) has escalated the need for a case-oriented clinical approach that provides timely diagnosis and management. The aim of this study is to share our experience in managing 64 MIS-C patients of North African ethnicity guided by a risk-based algorithm. Sixty-four patients met the inclusion criteria, 19 (30%) patients were categorized as mild and moderate risk groups and cared for in an isolation ward and 45 patients who belonged to the high-risk group (70%) were admitted to the pediatric intensive care unit (PICU). Positive laboratory evidence of COVID-19 was found in 62 patients. Fever and dysfunction in 2 or more organs were confirmed in all cases (100%). Fifty patients (78%) presented with gastrointestinal symptoms, meanwhile only 10 patients (16%) had respiratory manifestations. Cardiac involvement was reported in 55 (86%) cases; hypotension and shock were found in 45 patients (70%) therein circulatory support and mechanical ventilations were needed for 45 and 13 patients respectively. Intravenous immunoglobulins (IVIG) were used for all cases and methylprednisolone was used in 60 patients (94%). Fifty-eight (91%) patients were discharged home after an average of 9 days of hospitalization. The mortality rate was 9% (6 patients). Conclusion. A single Egyptian center experience in the management of MIS-C patients guided by a proposed bed side algorithm is described. The algorithm proved to be a helpful tool for first-line responders, and helped initiate early treatment with IVIG.

Predictors of transient left ventricular dysfunction following transcatheter patent ductus arteriosus closure in pediatric age

OBJECTIVES

To evaluate the left ventricular function before and after transcatheter percutaneous patent ductus arteriosus (PDA) closure, and to identify the predictors of myocardial dysfunction post-PDA closure if present.

INTERVENTIONS

Transcatheter PDA closure; conventional, Doppler, and tissue Doppler imaging; and speckle tracking echocardiography.

OUTCOME MEASURES

To determine the feasibility and reliability of tissue Doppler and myocardial deformation imaging for evaluating myocardial function in children undergoing transcatheter PDA closure.

PATIENTS AND METHODS

Forty-two children diagnosed with hemodynamically significant PDA underwent percutaneous PDA closure. Conventional, Doppler, and tissue Doppler imaging, and speckle-derived strain rate echocardiography were performed at preclosure and at 48 hours, 1 month, and 6 months postclosure. Tissue Doppler velocities of the lateral and septal mitral valve annuli were obtained. Global and regional longitudinal peak systolic strain values were determined using two-dimensional speckle tracking echocardiography.

RESULTS

The median age of the patients was 2 years and body weight was 15 kg, with the mean PDA diameter of 3.11 ± 0.99 mm. M-mode measurements (left ventricular end diastolic diameter, left atrium diameter to aortic annulus ratio, ejection fraction, and shortening fraction) reduced significantly early after PDA closure (p < 0.001). After 1 month, left ventricular end diastolic diameter and left atrium diameter to aortic annulus ratio continued to decrease, while ejection fraction and fractional shortening improved significantly. All tissue Doppler velocities showed a significant decrease at 48 hours with significant prolongation of global myocardial function (p < 0.001) and then were normalized within 1 month postclosure. Similarly, global longitudinal strain significantly decreased at 48 hours postclosure (p < 0.001), which also recovered at 1 month follow-up. Preclosure global longitudinal strain showed a good correlation with the postclosure prolongation of the myocardial performance index.

CONCLUSION

Transcatheter PDA closure causes a significant decrease in left ventricular performance early after PDA closure, which recovers completely within 1 month. Preclosure global longitudinal strain can be a predictor of postclosure myocardial dysfunction.

HLA class II associations with rheumatic heart disease are more evident and consistent among clinically homogeneous patients

BACKGROUND

Discrepancies in reported HLA class II associations with rheumatic heart disease (RHD) may have been due to inaccuracies of serological typing reagents and/or lack of defined clinical classification of patients analyzed. The molecular association between HLA and RHD was investigated in patients with defined clinical outcome.

METHODS AND RESULTS

Class II allele/haplotype distribution was determined in 2 groups of RHD patients (n=88) and a control group (n=59). Patients were divided into the mitral valve disease (MVD) category (ie, those with mitral regurgitation with or without mitral stenosis) and the multivalvular lesions (MVL) category, with impairment of aortic and/or tricuspid valves in addition to mitral valve damage. The MVD category (n=65) accounted for 74% of patients and included significantly fewer recurrent RF episodes compared with MVL patients (P=0.002).

CONCLUSIONS

Significant increases in DRB1*0701 and DQA1*0201 alleles and DRB1*0701-DQA1*0201 haplotypes were found in patients. Removal of the MVL patients from analysis increased the strength of HLA associations among the MVD sample. The frequency of DQA1*0103 allele was decreased and the DQB1*0603 allele was absent from the patient group, suggesting that these alleles may confer protective effects against RHD. DQ alleles in linkage disequilibrium with DR alleles appear to influence risk/protection effect: whereas the DRB1*13-DQA1*0501-3-DQB1*0301 haplotype showed a trend toward risk, the DRB1*13-DQA1*0103-DQB1*0603 haplotype was absent in the RHD sample. Our data indicate that certain class II alleles/haplotypes are associated with risk or protection from RHD and that these associations appear to be stronger and more consistent when analyzed in patients with relatively more homogeneous clinical manifestations.

Preferential recognition of human myocardial antigens by T lymphocytes from rheumatic heart disease patients

Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) are autoimmune sequelae of upper respiratory infections with group A streptococci (GAS). To gain a better understanding of the pathogenesis of these diseases, we examined the in vitro proliferative responses of peripheral blood mononuclear cells (PBMC) from RHD patients to human myocardial proteins in a T-cell Western assay. A number of myocardial proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were recognized by PBMC from both patients and controls. However, PBMC from a significant percentage of RHD patients (40%) responded to a discrete band of myocardial proteins migrating with an apparent molecular mass of 50 to 54 kDa while none of the control subject PBMC responded to this protein band (P < or = 0.0001). To further investigate the link between infections with GAS and autoimmune carditis, we studied the proliferative responses of PBMC from patients and controls to myocardial proteins before and after in vitro stimulation of the cells with opsonized GAS isolated from ARF patients. Priming of PBMC with rheumatogenic GAS caused the percentage of RHD patients responding to the 50- to 54-kDa myocardial proteins to increase from 43 to 90% (P < or = 0.0284). By contrast, PBMC from control subjects failed to recognize the 50- to 54-kDa myocardial proteins even after stimulation with the opsonized streptococci (P < or = 0.0001). The assay sensitivity was increased from 40 to 90% after priming of a patient's cells with opsonized GAS, but the positive predictive value was 100% in both unprimed and primed cultures. Antibodies generated to partially purified 50- to 54-kDa myocardial proteins did not cross-react with either streptococcal homogenates, purified M protein, myosin, laminin, or vimentin, suggesting a lack of cross-reactivity at the humoral level. This study suggests that the 50- to 54-kDa myocardial proteins contain a putative antigen that is preferentially recognized by T cells from RHD patients and demonstrates that exposure to streptococcal antigens enhances the ability of patients to recognize these proteins.