title: Palatal Petechiae in the Absence of Group A Streptococcus in Pediatric Patients with Acute-Onset Neuropsychiatric Deterioration: A Cohort Study.
abstract: BACKGROUND
  Palatal petechiae are 95% specific for streptococcal pharyngitis. Despite this, and despite prior research demonstrating that Group A Streptococcus (GAS) is a common antecedent to pediatric acute-onset neuropsychiatric syndrome (PANS) episodes, we anecdotally observed a low rate of documented GAS in patients with PANS and palatal petechiae. This retrospective chart review was conducted to formally report the rate of palatal petechiae and concurrent GAS in a cohort of patients with PANS and investigate other etiologic factors.
  
  
  METHODS
  The clinical notes of 112 patients seen at the Stanford PANS Clinic who met PANS research criteria were reviewed for mention of palatal petechiae. The medical records of patients who demonstrated palatal petechiae on physical examination were reviewed for signs of infection, a clinical history of trauma, and laboratory results that could indicate other causes of petechiae.
  
  
  RESULTS
  Twenty-three patients had documented palatal petechiae on physical examination (ages 5-16, 13/23 [57%] male). Fifteen patients had a rapid GAS test and GAS culture in the Stanford PANS clinic, all with negative results. Evidence of recent GAS infection was found in 8/23 (32%) patients (elevated GAS titers [n = 6] or documentation of a positive rapid GAS test at another facility [n = 2]), one of whom also had potential herpes simplex virus (HSV) infection. One patient had potential HSV infection and recent palatal trauma. No patients had thrombocytopenia. 14/23 (61%) of patients with palatal petechiae had no discernable cause of petechiae. 10/19 (53%) of patients had antihistone antibodies.
  
  
  CONCLUSIONS
  Despite the established relationship between palatal petechiae and GAS, no patient with palatal petechiae in our clinic tested positive for GAS and only 32% had evidence of recent GAS. Most did not have an identifiable cause for the palatal lesions. This finding suggests the potential for alternative causes of palatal petechiae or undetectable GAS in our patient population. The high prevalence of palatal petechiae without GAS infection suggests that the pathogenesis of PANS is multifactorial and may involve disruption or inflammation of the microvasculature. Additional research is needed to further elucidate these findings.
authors.affiliation: 1 Divisions of Pediatric, Department of Allergy, Immunology, and Rheumatology, Palo Alto, California.|2 Stanford PANS Clinic and Research Program at Lucile Packards Children's Hospital, Stanford School of Medicine , Palo Alto, California.
authors.forename: Talia
authors.initials: T
authors.lastname: Mahony
authors.affiliation: 3 Divisions of Pediatric, Department of Otolarynthology, Palo Alto, California.
authors.forename: Douglas
authors.initials: D
authors.lastname: Sidell
authors.affiliation: 4 Divisions of Pediatric, Department of Infectious Disease, Palo Alto, California.
authors.forename: Hayley
authors.initials: H
authors.lastname: Gans
authors.affiliation: 5 Pediatric Infectious Disease, University of Missouri School of Medicine , Columbia Missouri.
authors.forename: Michael
authors.initials: M
authors.lastname: Cooperstock
authors.affiliation: 1 Divisions of Pediatric, Department of Allergy, Immunology, and Rheumatology, Palo Alto, California.|2 Stanford PANS Clinic and Research Program at Lucile Packards Children's Hospital, Stanford School of Medicine , Palo Alto, California.
authors.forename: Kayla
authors.initials: K
authors.lastname: Brown
authors.affiliation: 2 Stanford PANS Clinic and Research Program at Lucile Packards Children's Hospital, Stanford School of Medicine , Palo Alto, California.
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Cheung
authors.affiliation: 2 Stanford PANS Clinic and Research Program at Lucile Packards Children's Hospital, Stanford School of Medicine , Palo Alto, California.
authors.forename: Bahare
authors.initials: B
authors.lastname: Farhadian
authors.affiliation: 2 Stanford PANS Clinic and Research Program at Lucile Packards Children's Hospital, Stanford School of Medicine , Palo Alto, California.
authors.forename: Melissa
authors.initials: M
authors.lastname: Gustafson
authors.affiliation: 2 Stanford PANS Clinic and Research Program at Lucile Packards Children's Hospital, Stanford School of Medicine , Palo Alto, California.|6 Divisions of Pediatric, Department of Child & Adolescent Psychiatry, Stanford University School of Medicine , Palo Alto, California.
authors.forename: Margo
authors.initials: M
authors.lastname: Thienemann
authors.affiliation: 1 Divisions of Pediatric, Department of Allergy, Immunology, and Rheumatology, Palo Alto, California.|2 Stanford PANS Clinic and Research Program at Lucile Packards Children's Hospital, Stanford School of Medicine , Palo Alto, California.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Frankovich
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D002648:Child; D002653:Child Behavior Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D065886:Neurodevelopmental Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D010159:Palate / Q000382:microbiology / Q000473:pathology*; D011693:Purpura / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D012189:Retrospective Studies; D013290:Streptococcal Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D013297:Streptococcus pyogenes / Q000302:isolation & purification*
keywords: PANS; child; group A streptococcus; infection; petechiae; youth