Katia Stankovic Stojanovic1, Véronique Hentgen2, Soraya Fellahi3, Sophie Georgin-Lavialle4, Serge Amselem5, Gilles Grateau4, Jean-Philippe Bastard3, Olivier Steichen6. 1. Assistance publique-hôpitaux de Paris, hôpital Tenon, Centre de référence adulte de la fièvre méditerranéenne familiale, service de médecine interne, F-75020 Paris, France; Sorbonne Universités, UPMC Université Paris 06, Département hospitalo-universitaire I2B, F-75013 Paris, France. Electronic address: katia.stankovic@aphp.fr. 2. Centre hospitalier de Versailles, centre de référence des maladies autoinflammatoires rares de l'enfant (CeRéMAI), service de pédiatrie, F-78150 Le Chesnay, France. 3. Sorbonne Universités, UPMC Université Paris 06, Département hospitalo-universitaire I2B, F-75013 Paris, France; Assistance publique-hôpitaux de Paris, hôpital Tenon, UF Bio-marqueurs inflammatoires et métaboliques, Service de biochimie, F-75020 Paris, France. 4. Assistance publique-hôpitaux de Paris, hôpital Tenon, Centre de référence adulte de la fièvre méditerranéenne familiale, service de médecine interne, F-75020 Paris, France; Sorbonne Universités, UPMC Université Paris 06, Département hospitalo-universitaire I2B, F-75013 Paris, France; Sorbonne Université, UPMC université Paris 06, INSERM UMR_S933, F-75012 Paris, France. 5. Sorbonne Universités, UPMC Université Paris 06, Département hospitalo-universitaire I2B, F-75013 Paris, France; Sorbonne Université, UPMC université Paris 06, INSERM UMR_S933, F-75012 Paris, France; Assistance publique-hôpitaux de Paris, hôpital Armand-Trousseau, Centre de référence adulte de la fièvre méditerranéenne familiale, Laboratoire de génétique, F-75012 Paris, France. 6. Assistance publique-hôpitaux de Paris, hôpital Tenon, Centre de référence adulte de la fièvre méditerranéenne familiale, service de médecine interne, F-75020 Paris, France; Sorbonne Universités, UPMC Université Paris 06, Département hospitalo-universitaire I2B, F-75013 Paris, France; Sorbonne Universités, UPMC Université Paris 06, INSERM, LIMICS, F-75005 Paris, France.
Abstract
INTRODUCTION: Monitoring SAA level in attack-free FMF patients is recommended in order to adjust colchicine dose, and minimize the risk of AA amyloidosis. In countries where this test is not available, C-reactive protein (CRP), another acute phase reactant, is used instead. However, CRP is low and SAA is increased in some patients and vice versa. OBJECTIVES: To determine the threshold of CRP corresponding to SAA<10mg/L in patients with FMF and to assess their concordance at the patient level. PATIENTS AND METHODS: Consecutive FMF patients in attack-free period and no other cause of intermittent inflammation including infections were recruited during their regular visits in the French reference center for FMF. Demographic and genetic data were recorded; CRP and SAA were tested simultaneously. The threshold value of CRP corresponding to 10mg/L for SAA was determined and the concordance between the two markers was assessed with Cohen's kappa index. RESULTS: 399 samples were obtained from 218 patients, mean age of 27years (33% under 18years old), 55% of female, from Sephardic Jewish origin in 71%. MEFV mutation was M694V homozygous or compound heterozygous in 52%, and simple heterozygous in 18%. Six patients had AA amyloidosis. The appropriate CRP threshold was found to be 5mg/L in children and 8.75mg/L in adults. Global agreement with SAA<10mg/L was 84% [95% confidence interval: 82 to 86%], leading to a kappa index at 0.62 [95% confidence interval: 0.57 to 0.68]. CONCLUSION: CRP<5mg/L in FMF children or 8.75mg/L in FMF adults during attack-free periods might be a convenient substitute to guide therapeutic decisions when SAA is unavailable.
INTRODUCTION: Monitoring SAA level in attack-free FMFpatients is recommended in order to adjust colchicine dose, and minimize the risk of AA amyloidosis. In countries where this test is not available, C-reactive protein (CRP), another acute phase reactant, is used instead. However, CRP is low and SAA is increased in some patients and vice versa. OBJECTIVES: To determine the threshold of CRP corresponding to SAA<10mg/L in patients with FMF and to assess their concordance at the patient level. PATIENTS AND METHODS: Consecutive FMFpatients in attack-free period and no other cause of intermittent inflammation including infections were recruited during their regular visits in the French reference center for FMF. Demographic and genetic data were recorded; CRP and SAA were tested simultaneously. The threshold value of CRP corresponding to 10mg/L for SAA was determined and the concordance between the two markers was assessed with Cohen's kappa index. RESULTS: 399 samples were obtained from 218 patients, mean age of 27years (33% under 18years old), 55% of female, from Sephardic Jewish origin in 71%. MEFV mutation was M694V homozygous or compound heterozygous in 52%, and simple heterozygous in 18%. Six patients had AA amyloidosis. The appropriate CRP threshold was found to be 5mg/L in children and 8.75mg/L in adults. Global agreement with SAA<10mg/L was 84% [95% confidence interval: 82 to 86%], leading to a kappa index at 0.62 [95% confidence interval: 0.57 to 0.68]. CONCLUSION:CRP<5mg/L in FMFchildren or 8.75mg/L in FMF adults during attack-free periods might be a convenient substitute to guide therapeutic decisions when SAA is unavailable.
Authors: T Kallinich; N Blank; T Braun; E Feist; U Kiltz; U Neudorf; P T Oommen; C Weseloh; H Wittkowski; J Braun Journal: Z Rheumatol Date: 2019-02 Impact factor: 1.372