Kawasaki disease and the environment: an enigmatic interplay

Kawasaki disease (KD) is a common systemic vasculitis of childhood. Although it has been almost 6 decades since Dr. Tomisaku Kawasaki reported the first case series of KD, the underlying cause remains a mystery. KD is a self-limiting disease. However, a dreaded complication is development of coronary artery abnormalities (CAAs). KD is the most common cause of acquired heart disease in children in the developed world and is being increasingly reported from developing countries too. Over the years, significant observations have been made about epidemiology of KD. It usually affects children below 5, has male preponderance and has significantly higher incidence in North East Asian countries. While several hypotheses have been proffered for etiology of KD, none have been conclusive. These include associations of KD epidemics in Japan and the United Stated with changes in tropospheric wind patterns suggesting wind-borne agents, global studies showing peaks of incidence related to season, and increased rates in populations with a higher socioeconomic profile related to hygiene hypothesis and vaccination. Furthermore, the self-limiting, febrile nature of KD suggests an infectious etiology, more so with sudden decline noted in cases in Japan with onset of COVID-19 mitigation measures. Finally, single nucleotide polymorphisms have been identified as possible risk alleles in patients with KD and their significance in the pathogenesis of this disease are also being defined. The purpose of this review is to elucidate the puzzling associations of KD with different environmental factors. Looking at patterns associated with KD may help us better predict and understand this disease

CD40 gene polymorphism and its expression in children with Kawasaki disease from North India: a preliminary case–control study and meta-analysis

IntroductionCD40 gene single-nucleotide polymorphisms (SNPs) have been associated with susceptibility and development of coronary artery abnormalities (CAAs) in children with Kawasaki disease (KD) in Japanese, Chinese, and Taiwanese populations. However, data on SNPs of the CD40 gene in patients with KD from the Indian subcontinent are not available. We studied the CD40 gene polymorphisms and its expression in children with KD from North India.MethodsSNPs of the CD40 gene (rs4810485, rs1535045) were studied using Sanger sequencing. CD40 expression was studied by flow cytometry. Meta-analysis was carried out to assess the role of both SNPs of the CD40 gene in KD. GRADEpro GDT software (v.3.2) was used to assess the “certainty of evidence.”ResultsForty-one patients with KD and 41 age-, sex-matched febrile controls were enrolled. However, none of the alleles and genotypes of the CD40 gene were found to be associated with KD. CD40 expression was higher in KD and in KD with CAAs compared to controls, but it failed to reach statistical significance. In a meta-analysis, the T allele of rs153045 was found to be significantly associated with KD (OR = 1.28; 95% confidence interval (: 1.09–1.50; p = 0.002). The GRADE of evidence for this outcome, however, is of “ very low certainty.”ConclusionThe present study found no association between SNPs (rs4810485 and rs153045) and susceptibility to KD. This could be a reflection of a modest sample size. CD40 expression was higher in KD and in KD with CAAs. In the meta-analysis, the T allele of rs153045 was significantly associated with KD. Our study confirms a significant genetic heterogeneity in KD among different ethnicities

Primary Immunodeficiency Disorders in India—A Situational Review

Primary immunodeficiency disorders (PIDs) are a group of genetic defects characterized by abnormalities of one or more components of the immune system. While there have been several advances in diagnosis, management, and research in the field of PIDs, they continue to remain underdiagnosed, especially in the less affluent countries. Despite several limitations and challenges, India has advanced significantly in the field of PIDs in the last few years. In this review, we highlight the progress in the field of PIDs in India over the last 25 years, the difficulties faced by clinicians across the country, the current state of PIDs in India and the future prospects

Systemic toxicity of topical corticosteroids

Corticosteroids are known to cause many ocular and systemic side effects when administered by oral or parenteral routes. Corticosteroid induced systemic toxicity secondary to topical steroid eye drops is rare. A 6-week-old, male infant was brought to our tertiary eye care center with bilateral congenital cataracts. The child underwent phacoaspiration with primary posterior capsulotomy without intraocular lens implantation in both eyes at an interval of 6 weeks. Child was initiated on topical betamethsone 0.1% eight times a day, tobramycin 0.3% six times a day, homatropine 2% twice a day, and carboxymethylcellulose 0.5% four times a day. Two and four weeks later he underwent surgical membranectomy in the right and left eye respectively followed by frequent use of topical steroids, initially given 1 hourly and then tapered weekly in the follow-up period. The patient showed increase in intraocular pressure and gain in body weight along with development of cushingoid habitus nearly 6 to 8 weeks after starting topical steroids. These side effects started weaning off following the reduction in dose of topical steroids, suggesting the role of the corticosteroid-related systemic side effects. This case highlights the serious systemic side effects secondary to increased frequency and duration of topical corticosteroid use in infancy. Hence, dosage of topical steroids should be adjusted in its therapeutic range to prevent their ocular and systemic side effects. Therefore, close monitoring is advocated for children using topical corticosteroids to prevent serious ocular and systemic side effects