ORIGINAL ARTICLE Changing epidemiology of acute post-streptococcal glomerulonephritis in Northeast Florida: a comparative study Mohammad Ilyas & Asad Tolaymat Received: 15 November 2007 / Revised: 9 January 2008 / Accepted: 11 January 2008 / Published online: 29 March 2008 # IPNA 2008 Abstract The objective of this study was to review the epidemiological patterns of acute post-streptococcal glo- merulonephritis (APSGN) in a pediatric population. We compared incidence, pathogenesis, clinical presentation and outcomes in two APSGN pediatric patient cohorts in northeastern Florida. Retrospective medical records were reviewed of children who were admitted to our institution with a diagnosis of APSGN. Patients admitted between 1999 and 2006 (recent cohort) were compared with a previously reported cohort of patients admitted between 1957 and 1973 (earlier cohort). The recent cohort com- prised 45 children with APSGN of whom 87% were male and 13% were female; the median age was 7 years, and there was an average incidence of 6.4 patients per year. The earlier cohort comprised 153 children with APSGN of whom 62% were male and 38% were female; the median age 4.25 years, and there was an average incidence of 10.9 patients per year. The recent cohort was predominantly White-American (62%) and the earlier cohort predomi- nately African American (87%). In the recent cohort, 64% of patients had antecedent pharyngitis, and in the earlier cohort, 66% of patients had antecedent pyoderma. In the recent cohort, 11% of APSGN cases occurred between August to October, and in the earlier cohort, 50% occurred during these months. In the recent cohort, symptoms of APSGN at presentation were milder and all cases recov- ered, but in the earlier cohort two deaths (1.3% mortality) were reported. In conclusion, there has been a decline in the incidence and severity of APSGN at our institute in recent decades. Pharyngitis has replaced impetigo as the predomi- nant cause of APSGN. The etiological agent for impetigo has changed over the last decade, which has impacted the incidence, racial distribution, seasonal variation and severity of APSGN. Keywords Acute post-streptococcal glomerulonephritis . Impetigo . Incidence . Pharyngitis Introduction Acute post-streptococcal glomerulonephritis (APSGN) pri- marily affects children, with spontaneous recovery occur- ring in almost all patients, including those who develop renal insufficiency during the acute phase [1]. Irreversible renal failure likely occurs in less than 1% of all pediatric patients and in a slightly higher percentage of adults [2]. The incidence of clinically detectable glomerulonephritis during an epidemic is up to 10% of children with pharyngitis and up to 25% of children with impetigo [3]. Despite sporadic outbreaks, the incidence of APSGN has decreased over the last few decades [4], and although the reasons for this decline have not been clearly delineated, the wide- spread use of antibiotics, changes in etiological pathogens, altered susceptibility of the host, better health care delivery and improved socioeconomic conditions clearly play major roles [5,6]. Pediatr Nephrol (2008) 23:1101–1106 DOI 10.1007/s00467-008-0778-1 M. Ilyas : A. Tolaymat Pediatric Nephrology, University of Florida/Jacksonville, Jacksonville, FL, USA M. Ilyas (*) 820 Prudential drive Suite #405, Jacksonville, FL 32207, USA e-mail: mohammad.ilyas@jax.ufl.edu