title: Clinical features of hereditary angioedema in Chinese patients: new findings and differences from other populations.
abstract: BACKGROUND
  Hereditary angioedema (HAE), caused by C1 inhibitor deficiency, is characterized by recurrent subcutaneous or submucosal swelling. Because it is rare, data on clinical features, especially in Chinese patients, are not comprehensive.
  
  
  OBJECTIVE
  Our aim was to identify the characteristics of HAE in a Chinese population and enhance clinical knowledge of this disease.
  
  
  METHODS
  One hundred and fifty-eight symptomatic patients were studied retrospectively. Data were obtained from medical records. Statistical analyses were performed using statistical software package: R version 2.14.0.
  
  
  RESULTS
  The majority of patients first experienced attacks during the second (42%) and third (32%) decades: the mean onset of symptoms was at the age of 21.25 years. The percentage of patients having experienced a swelling at least once for the following sites were: extremities (83.54%); pharyngolarynx (58.86%); face (55.06%); gastrointestinal tract (34.17%); trunk (18.35%) and genitalia (15.33%). Rare manifestations included melaena, swollen gastric mucosa inverting into the oesophagus, pleural effusion, dysuria and syncope. For patients who first experienced swelling in pre-adolescence, 41.67% noted intensified attack rates when they entered puberty. In pregnancy, 61.70% did not note a change in HAE attack frequency.
  
  
  CONCLUSIONS
  Compared with previous studies, the mean age of symptom onset is older. The frequencies of abdominal attacks occurring in patients on the Chinese Mainland, as well as in Taiwan and Japan, appears much lower than in western countries. Ethnic or environmental differences may contribute to this finding. Melaena and gastric mucosa inverting into the oesophagus secondary to edema are first reported here.
authors.affiliation: Department of Allergy.
authors.forename: Ying-Yang
authors.initials: YY
authors.lastname: Xu
authors.forename: Ying
authors.initials: Y
authors.lastname: Jiang
authors.forename: Yu-Xiang
authors.initials: YX
authors.lastname: Zhi
authors.forename: Jia
authors.initials: J
authors.lastname: Yin
authors.forename: Liang-Lu
authors.initials: LL
authors.lastname: Wang
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Wen
authors.forename: Jian-Qing
authors.initials: JQ
authors.lastname: Gu
authors.forename: Kai
authors.initials: K
authors.lastname: Guan
authors.forename: Hong-Yu
authors.initials: HY
authors.lastname: Zhang
mesh_terms: D015746:Abdominal Pain / Q000209:etiology; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D054179:Angioedemas, Hereditary / Q000150:complications* / Q000453:epidemiology*; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D018450:Disease Progression; D053159:Dysuria / Q000209:etiology; D005121:Extremities; D005145:Face; D005260:Female; D005767:Gastrointestinal Diseases / Q000453:epidemiology / Q000209:etiology; D005835:Genitalia; D006801:Humans; D007818:Laryngeal Diseases / Q000453:epidemiology / Q000209:etiology; D008297:Male; D008551:Melena / Q000209:etiology; D008875:Middle Aged; D062072:Patient Acuity; D010608:Pharyngeal Diseases / Q000453:epidemiology / Q000209:etiology; D010996:Pleural Effusion / Q000209:etiology; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000453:epidemiology*; D012189:Retrospective Studies; D013575:Syncope / Q000209:etiology; D060726:Torso; D055815:Young Adult