Chronic granulomatous disease (CGD) is an inherited defect of phagocyte function due to defective NADPH oxidase. Patients with CGD are not able to effectively clear the infections because of the defect in the phagocyte production of oxygen free radicals and are prone to recurrent bacterial and fungal infections. Inflammatory complications are also noted in CGD such as colitis, non-infective granulomas causing gastrointestinal or urinary tract obstruction, hemophagocytic lymphohistiocytosis, and arthritis. Studies on toll-like receptor pathways and neutrophil extracellular traps in CGD have shed light on the role of NADPH oxidase in the innate immunity and pathogenesis of infections in CGD. Some reports also indicate a reduction of memory B cells and defective production of functional antibodies in CGD. Though the exact mechanisms for non-infective inflammatory complications in CGD are not yet clear, studies on efferocytosis and defective autophagy with inflammasome activation have made a substantial contribution to our understanding of the pathogenesis of inflammation in CGD. We also discuss the clinical and molecular features of p40phox defects and a newer genetic defect, EROS. Clinical phenotypes of X-linked carriers of CYBB are also discussed.

Severe Combined Immunodeficiency (SCID) is an inherited group of rare, life-threatening disorders due to the defect in T cell development and function. Clinical manifestations are characterised by recurrent and severe bacterial, viral, and fungal opportunistic infections that start from early infancy period. Haematopoietic stem cell transplantation (HSCT) is the treatment of choice. The pattern of inheritance of SCID may be X-linked or autosomal recessive. Though the diagnosis of SCID is usually established by flow cytometry-based tests, genetic diagnosis is often needed for genetic counselling, prognostication, and modification of pre-transplant chemotherapeutic agents. This review aims to highlight the genetic aspects of SCID.

Objective: Precise evaluation of coronary artery abnormalities (CAAs) in Kawasaki disease (KD) is essential. The aim of this study is to determine role of CT coronary angiography (CTCA) for detection of CAAs in distal segments of coronary arteries in patients with KD.Methods: CTCA findings of KD patients with distal coronary artery involvement were compared with those on transthoracic echocardiography (TTE) during the period 2013–21.Results: Among 176 patients with KD who underwent CTCA (128-Slice Dual Source scanner), 23 (13.06%) had distal CAAs (right coronary—15/23; left anterior descending—14/23; left circumflex—4/23 patients). CTCA identified 60 aneurysms—37 proximal (36 fusiform; 1 saccular) and 23 distal (17 fusiform; 6 saccular); 11 patients with proximal aneurysms had distal contiguous extension; 9 patients showed non-contiguous aneurysms in both proximal and distal segments; 4 patients showed distal segment aneurysms in absence of proximal involvement of same coronary artery; 4 patients had isolated distal CAAs. On TTE, only 40 aneurysms could be identified. Further, distal CAAs could not be identified on TTE. CTCA also identified complications (thrombosis, mural calcification and stenosis) that were missed on TTE.Conclusions: CAAs can, at times, occur in distal segments in isolation and also in association with, or extension of, proximal CAAs. CTCA demonstrates CAAs in distal segments of coronary arteries, including branches, in a significant number of children with KD—these cannot be detected on TTE. CTCA may therefore be considered as a complimentary imaging modality in children with KD who have CAAs on TTE.