title: [Complement terminal fraction deficiency revealed at first invasive meningococcal infection].
abstract: Prevalence of complement protein deficiency in the general population is rare and its association with an increased risk of meningococcal infection is well established. However, management of these patients with potentially serious infections and indications warranting a search for such a deficiency have not met with consensus. We report the case of a 3-year-old child with no significant medical history who consulted in an emergency department for a fever after a stay in Senegal. Medical explorations concluded in septicemia and meningococcal W meningitis with a favorable outcome. Secondarily, we highlighted a complete deficiency of complement component C6. We diagnosed the same deficit in his twin sister who presented no infection. A long-term prophylactic antibiotic therapy and a meningococcal conjugate vaccine A,C,Y,W were set up for the twins. Recurrent invasive meningococcal infections and highlighting certain meningococcal serogroups are currently indications for complement protein exploration. We suggest expanding the search criteria for a complement protein deficiency after a single event of invasive meningococcal infection. This is an easy, rapid, and cost-effective screening system by dosage of CH50, C3, C4, and AP50. The arrival of the new meningococcal B vaccine will contribute to improving these patients' care. Family screening is necessary for prophylactic therapy.
authors.affiliation: Service de pédiatrie, université Paris 13, Sorbonne Paris Cité, hôpital Jean-Verdier, AP-HP, avenue du 14-Juillet, 93143 Bondy cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: de Marcellus
authors.affiliation: Centre national de référence des méningocoques, Institut Pasteur, 26-28, rue du Dr-Roux, 75015 Paris, France.
authors.forename: M-K
authors.initials: MK
authors.lastname: Taha
authors.affiliation: Service de pédiatrie, université Paris 13, Sorbonne Paris Cité, hôpital Jean-Verdier, AP-HP, avenue du 14-Juillet, 93143 Bondy cedex, France.
authors.forename: J
authors.initials: J
authors.lastname: Gaudelus
authors.affiliation: Laboratoire d'immunologie biologique, université Paris 5, hôpital européen Georges-Pompidou, AP-HP, 20, rue Leblanc, 75015 Paris, France.
authors.forename: V
authors.initials: V
authors.lastname: Fremeaux-Bacchi
authors.affiliation: Service de pédiatrie, université Paris 13, Sorbonne Paris Cité, hôpital Jean-Verdier, AP-HP, avenue du 14-Juillet, 93143 Bondy cedex, France.
authors.forename: L
authors.initials: L
authors.lastname: de Pontual
authors.affiliation: Service de pédiatrie, université Paris 13, Sorbonne Paris Cité, hôpital Jean-Verdier, AP-HP, avenue du 14-Juillet, 93143 Bondy cedex, France. Electronic address: tamazoust.guiddir@jvr.aphp.fr.
authors.forename: T
authors.initials: T
authors.lastname: Guiddir
mesh_terms: D002675:Child, Preschool; D003183:Complement C6 / Q000172:deficiency*; D000081208:Hereditary Complement Deficiency Diseases; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000150:complications* / Q000175:diagnosis; D008297:Male; D008585:Meningitis, Meningococcal / Q000276:immunology*
chemical_list: D003183:Complement C6