title: Seropositivity for Antibodies to DRS-G, a Virulence Factor from Streptococcus dysgalactiae subsp. equisimilis, Is an Independent Risk Factor for Poststreptococcus Glomerulonephritis and Chronic Kidney Disease in Mumbai, India.
abstract: The disease spectrum caused by Streptococcus dysgalactiae subsp. equisimilis resembles that of S. pyogenes (group A streptococcus [GAS]). These two bacterial species are closely related and possess many common virulence characteristics. While some GAS strains express virulence factors called streptococcal inhibitor of complement (SIC) and distantly related to SIC (DRS), some S. dysgalactiae subsp. equisimilis isolates express an orthologue of DRS, which is referred to as DRS-G. We reported previously that seropositivity for either anti-SIC or anti-DRS antibodies (Abs) is associated with poststreptococcal glomerulonephritis (PSGN). However, only seropositivity for anti-SIC Abs is associated with chronic kidney disease (CKD). We now extend the study to test whether seropositivity for anti-DRS-G Abs is also associated with these renal diseases. Stored serum samples collected for our previous study were tested by an enzyme-linked immunosorbent assay (ELISA) for Abs to DRS-G. The samples represented sera from 100 CKD adult patients, 70 adult end-stage renal disease (ESRD) patients, 25 PSGN pediatric patients, and corresponding age-matched control subjects. The proportion of PSGN, CKD, and ESRD patients who showed seroreaction to anti-DRS-G Abs was significantly higher than that of the corresponding age-matched controls, who in general exhibited seropositivity rates commensurate with the isolation rate of drsG-positive S. dysgalactiae subsp. equisimilis in the community during this study period. Since higher rates of seropositivity for anti-DRS-G Abs in the renal disease categories are resultant of previous infections with DRS-G-positive S. dysgalactiae subsp. equisimilis strains, we conclude the seropositivity is an additional risk factor for these renal diseases. In this regard, anti-DRS-G Abs have attributes similar to those of the anti-SIC Abs.
authors.affiliation: KEM Hospital, Mumbai, India.
authors.forename: Gouri P
authors.initials: GP
authors.lastname: Hule
authors.affiliation: KEM Hospital, Mumbai, India.
authors.forename: Mohan G
authors.initials: MG
authors.lastname: Karmarkar
authors.affiliation: Griffith University, Gold Coast Campus, Gold Coast, Queensland, Australia.
authors.forename: Ainslie
authors.initials: A
authors.lastname: Cameron
authors.affiliation: KEM Hospital, Mumbai, India.
authors.forename: Niwrutti
authors.initials: N
authors.lastname: Hase
authors.affiliation: KEM Hospital, Mumbai, India.
authors.forename: Uday
authors.initials: U
authors.lastname: Khopkar
authors.affiliation: KEM Hospital, Mumbai, India.
authors.forename: Preeti R
authors.initials: PR
authors.lastname: Mehta
authors.affiliation: QIMR Berghofer, Brisbane, Australia.
authors.forename: Celia L
authors.initials: CL
authors.lastname: McNeilly
authors.affiliation: The University of Sunshine Coast, Sippy Downs, Australia.
authors.forename: David
authors.initials: D
authors.lastname: McMillan
authors.affiliation: QIMR Berghofer, Brisbane, Australia sris@qimr.edu.au.
authors.forename: Kadaba S
authors.initials: KS
authors.lastname: Sriprakash
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005921:Glomerulonephritis / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007194:India / Q000453:epidemiology; D007223:Infant; D008297:Male; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D013290:Streptococcal Infections / Q000150:complications*; D013291:Streptococcus / Q000276:immunology*; D037521:Virulence Factors / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D037521:Virulence Factors