Roberto Massa1, Giulia Greco2, Manuela Testi3, Emanuele Rastelli2, Chiara Terracciano2, Erica Frezza2, Matteo Garibaldi4, Girolama A Marfia5, Franco Locatelli6, Nicola B Mercuri5, Eugenio Pompeo7, Giovanni Antonini4, Marco Andreani6. 1. Unit Malattie Neuromuscolari, Dipartimento Medicina dei Sistemi, Università di Roma Tor Vergata, Rome, Italy. massa@uniroma2.it. 2. Unit Malattie Neuromuscolari, Dipartimento Medicina dei Sistemi, Università di Roma Tor Vergata, Rome, Italy. 3. Unit Genetica Medica, Azienda Ospedaliera San Camillo-Forlanini, Rome, Italy. 4. Neurofisiopatologia, Dipartimento NESMOS, Ospedale S. Andrea, Sapienza Università di Roma, Rome, Italy. 5. Neurologia, Dipartimento Medicina dei Sistemi, Università di Roma Tor Vergata, Rome, Italy. 6. Laboratorio d'Immunogenetica dei Trapianti, Dipartimento di Oncoematologia e Terapia Cellulare e Genica, IRCCS OPBG, Rome, Italy. 7. Dipartimento Chirurgia Toracica, Università di Roma Tor Vergata, Rome, Italy.
Abstract
BACKGROUND: The relative prevalence of myasthenia gravis (MG) subtypes is changing, and their differential features and association with HLA class II alleles are not completely understood. METHODS: Age at onset, presence/absence of autoantibodies (Ab) and thymoma were retrospectively considered in 230 adult Italian patients. Clinical severity, assessed by MGFA scale, and the highest Ab titer were recorded. Furthermore, we performed low/high resolution typing of HLA-DRB1 and HLA-DQB1 alleles to detect associations of these loci with MG subtypes. RESULTS: There were two peaks of incidence: under 41 years of age, with female preponderance, and over 60 years, with higher male prevalence. The former group decreased and the latter increased significantly when comparing onset period 2008-2015 to 2000-2007. Thymomatous (TMG) patients showed a higher prevalence of severe phenotype and significantly higher anti-AChR Ab titer than non-thymomatous (NTMG) patients. Among the latter, those with onset after 60 years of age (LO-NTMG) displayed significantly higher Ab titers but lower MGFA grade compared to early-onset patients (< 41 years; EO-NTMG). Significant associations were found between HLA DQB1*05:01 and TMG patients and between DQB1*05:02 and DRB1*16 alleles and LO-NTMG with anti-AChR Ab. CONCLUSIONS: Two distinct cutoffs (< 41 and > 60 years) conveniently define EO-NTMG and LO-NTMG, with different characteristics. LO-NTMG is the most frequent disease subtype, with an increasing incidence. TMG patients reach higher clinical severity and higher antibody titers than NTMG patients. Moreover, TMG and LO-NTMG with anti-AChR Ab differ in their HLA-DQ association, providing further evidence that these two forms may have different etiologic mechanisms.
BACKGROUND: The relative prevalence of myasthenia gravis (MG) subtypes is changing, and their differential features and association with HLA class II alleles are not completely understood. METHODS: Age at onset, presence/absence of autoantibodies (Ab) and thymoma were retrospectively considered in 230 adult Italian patients. Clinical severity, assessed by MGFA scale, and the highest Ab titer were recorded. Furthermore, we performed low/high resolution typing of HLA-DRB1 and HLA-DQB1 alleles to detect associations of these loci with MG subtypes. RESULTS: There were two peaks of incidence: under 41 years of age, with female preponderance, and over 60 years, with higher male prevalence. The former group decreased and the latter increased significantly when comparing onset period 2008-2015 to 2000-2007. Thymomatous (TMG) patients showed a higher prevalence of severe phenotype and significantly higher anti-AChR Ab titer than non-thymomatous (NTMG) patients. Among the latter, those with onset after 60 years of age (LO-NTMG) displayed significantly higher Ab titers but lower MGFA grade compared to early-onset patients (< 41 years; EO-NTMG). Significant associations were found between HLA DQB1*05:01 and TMGpatients and between DQB1*05:02 and DRB1*16 alleles and LO-NTMG with anti-AChR Ab. CONCLUSIONS: Two distinct cutoffs (< 41 and > 60 years) conveniently define EO-NTMG and LO-NTMG, with different characteristics. LO-NTMG is the most frequent disease subtype, with an increasing incidence. TMGpatients reach higher clinical severity and higher antibody titers than NTMG patients. Moreover, TMG and LO-NTMG with anti-AChR Ab differ in their HLA-DQ association, providing further evidence that these two forms may have different etiologic mechanisms.
Authors: E Bartoccioni; F Scuderi; A Augugliaro; S Chiatamone Ranieri; D Sauchelli; P Alboino; M Marino; A Evoli Journal: Neurology Date: 2009-01-13 Impact factor: 9.910
Authors: Angelina H Maniaol; Ahmed Elsais; Åslaug R Lorentzen; Jone F Owe; Marte K Viken; Hanne Sæther; Siri T Flåm; Geir Bråthen; Margitta T Kampman; Rune Midgard; Marte Christensen; Anna Rognerud; Emilia Kerty; Nils Erik Gilhus; Chantal M E Tallaksen; Benedicte A Lie; Hanne F Harbo Journal: PLoS One Date: 2012-05-09 Impact factor: 3.240