Autoimmunity in Acute Poststreptococcal GN: A Neglected Aspect of the Disease

Acute poststreptococcal GN (APSGN) is the prototype of immune complex GN and is associated with manifestations of autoimmune reactivity that have been neglected as epiphenomena. Recently, studies have demonstrated transient antifactor B autoantibodies that activate the alternative complement pathway, bringing self-immunity to a central position in the pathogenesis of APSGN. Therefore, examining other manifestations of autoimmunity that have been reported in association with poststreptococcal GN is of interest. This article reviews the renal and extrarenal manifestations of autoimmune reactivity in APSGN and considers their potential relevance in modifying the usually benign clinical course of the disease. It also discusses related aspects of the nephritogenic antigens, complement activation, and genetic elements associated with immune reactivity and their potential relevance to the familial incidence of the disease.

Familial risk of Behçet’s disease among first-degree relatives: a population-based aggregation study in Korea

Objective Previous studies have indicated that Behçet’s disease (BD) has a genetic component, however population-level familial risk estimates are unavailable. We quantified the familial incidence and risk of BD in first-degree relatives (FDR) according to age, sex and type of family relationship. Methods Using the Korean National Health Insurance database, which has full population coverage and confirmed FDR information, we constructed a cohort of 21 940 795 individuals comprising 12 million families, which were followed for a familial occurrence of BD from 2002 to 2017. Age- and sex-adjusted incidence risk ratios for BD were calculated in individuals with affected FDR compared with those without affected FDR. Results Among the total study population, 53 687 individuals had affected FDR, of whom 284 familial cases developed BD with an incidence of 3.57/104 person-years. The familial risk (incidence) for BD was increased to 13.1-fold (2.71/104 person-years) in individuals with an affected father, 13.9-fold (3.11/104 person-years) with affected mother, 15.2-fold (4.9/104 person-years) with an affected sibling and the highest risk was 165-fold (46/104 person-years) with an affected twin. Familial risks showed age dependence, being higher in younger age groups. The sex-specific familial risk was similar in males and females. Conclusion This study provides quantified estimates of familial incidence and risk in FDR of BD patients in an entire population. Familial risks were higher within generation (sibling–sibling) vs between generations (parent–offspring). This implicates complex interactions between genetic factors and shared childhood environmental exposures in the pathogenesis of BD.

Familial Case of Cherubism from South India: Differential Diagnosis and Report of 2 Cases

Cherubism is a rare familial multilocular cystic lesion of the jaws. The condition clinically appears as a bilateral symmetric swelling of the cheeks in children and is the primary reason for referral. It is a rare lesion of the jaws that has a dominant pattern of inheritance. We report two cases of cherubism, that of a boy and his mother suggestive of a strong familial incidence. A variety of lesions of the jaw mimic this condition and hence the differential diagnosis has been emphasised.