Acta Dermato-Venereologica 98-8CompleteContent | Page 10

CLINICAL REPORT

753 Advances in dermatology and venereology ActaDV Acta Dermato-Venereologica ActaDV

Epidemiological Analysis of Major Complications Requiring Medical Intervention in Patients with Neurofibromatosis 1
Yuichi YOSHIDA 1 , Yuko EHARA 1 , Monji KOGA 2 , Shinichi IMAFUKU 2 and Osamu YAMAMOTO 1
1
Division of Dermatology , Department of Medicine of Sensory and Motor Organs , Faculty of Medicine , Tottori University , Yonago , and
2
Department of Dermatology , Fukuoka University School of Medicine , Fukuoka , Japan
Neurofibromatosis 1 has various complications . To elucidate the frequency of neurofibromatosis 1-related major complications requiring medical intervention , a nationwide retrospective study was conducted of 3,530 patients with neurofibromatosis 1 registered from 2001 to 2014 in Japan . The ratio of certified patients requiring medical intervention (> stage 3 ) was 82 %. Patients classified in the most severe grade experienced dermatological complications ( 71.8 % of patients ), neurological complications ( 38.1 %) and bone complications ( 33.3 %). In patients with dermatological manifestations , medical treatment was needed for cutaneous neurofibromas ( 58 %), diffuse plexiform neurofibromas ( 31 %) and malignant peripheral nerve sheath tumours ( 10 %). Patients with neurological manifestations needed medical treatment mainly for brain tumours ( 53 %) and intellectual disability ( 26 %). Patients with bone manifestations needed medical treatment for pseudoarthrosis ( 9 %), scoliosis ( 55 %) and bone defects ( 16 %). It is necessary for physicians to be aware of neurofibromatosis 1-related complications requiring medical intervention in order to provide appropriate care for patients with neurofibromatosis 1 .
Key words : neurofibromatosis 1 ; epidemiology ; treatment ; survey .
Accepted May 22 , 2018 ; Epub ahead of print May 24 , 2018 Acta Derm Venereol 2018 ; 98 : 753 – 756 .
Corr : Yuichi Yoshida , Division of Dermatology , Department of Medicine of Sensory and Motor Organs , Faculty of Medicine , Tottori University , 86 Nishi-cho , Yonago-shi , Tottori 683-8503 , Japan . E-mail : yxyhifu1 @ med . tottori-u . ac . jp

Neurofibromatosis 1 ( NF1 ) is an autosomal dominant genetic disorder with a birth incidence of 1 in 3,000 – 4,000 individuals ( 1 ). NF1 is caused by a mutation of the NF1 gene ( 2 ) and has various complications , including dermatological , neurological and bone manifestations ( 3 ). We recently performed an epidemiological survey of patients with NF1 at the Division of Dermatology of Tottori University Hospital in Japan for assessment of disease severity . The survey found that 37.1 % of patients had major health impairments requiring medical treatment ( 4 ). In addition , two-thirds of patients classified in the most severe grade of NF1 experienced diffuse plexiform neurofibromas with secondary problems . However , the number of patients in that study was relatively

SIGNIFICANCE
Neurofibromatosis 1 is a genetic disease characterized by various symptoms such as dermatological , neurological and bone complications . This study presents the frequencies of complications requiring medical treatment in patients with neurofibromatosis . Our data suggest that most frequently treated symptoms were dermatological complications . It is important to know the characteristic complications requiring treatment in order to provide appropriate care for patients suffering from neurofibromatosis .
small ( n = 124 ) and the survey was limited to the field of dermatology . Since patients with a severe grade of NF1 have been supported by the public medical expenses subsidy system in Japan , we investigated the details of complications in cases requiring medical intervention that were registered in a national database . The aim of this nationwide study was to elucidate the clinical characteristics of NF1 and to determine the frequencies of complications requiring medical intervention .
PATIENTS AND METHODS
This retrospective study investigated clinical information for patients with NF1 registered at the Ministry of Health , Labour and Welfare from 2001 to 2014 from all over Japan . Patients with NF1 with a certain grade of severity are registered for research and exemption of medical fees as a government ’ s healthcare policy in Japan . Anonymous data for patients who met the diagnostic criteria of NF1 by the National Institutes of Health in 1988 ( 5 ) were analysed ( patients for whom essential information , such as age or sex , was missing were excluded ). Clinical information , including sex , age , family history and complications , was investigated . Clinical severity was also assessed by both the Japanese severity classification ( DNB classification ) ( 4 ) and Riccardi ’ s severity grade ( 6 ), as shown in Appendices S1 1 and S2 1 . The study protocol was approved by the ethics committees of Tottori University Hospital ( number 1704A005 ) and Fukuoka University Hospital ( 17-4-03 ).
RESULTS Patients ’ characteristics
Of the 3,530 registered patients , 25 were excluded from the study due to missing essential data . Finally , data for
1 https :// www . medicaljournals . se / acta / content / abstract / 10.2340 / 00015555-2975
This is an open access article under the CC BY-NC license . www . medicaljournals . se / acta Journal Compilation © 2018 Acta Dermato-Venereologica . doi : 10.2340 / 00015555-2975 Acta Derm Venereol 2018 ; 98 : 753 – 756