: 161  The Norse king Ivar the Boneless, who lived c. 800 CE, is speculated to have had OI as well.Nicolas de Malebranche is oft credited as being the first person to describe the physical characteristics of OI in his 1688 book The Search after Truth, in which he describes a man who has had his "bones broken in the places a murderers would be" all his life. His confident description of the pathology of the disorder, however, which creates what he termed «enfants monstrueux» ("monstrous children"), is scientifically void—he wrote that it was due to the mothers antepartum viewership of a public execution by breaking wheel. : 683 : 165–168 The earliest modern scientific studies of OI began in 1788 by Olof Jakob Ekman, who described the condition, which he termed "osteomalacia congenital", in his doctoral thesis and mentioned cases of it going back to 1678, all in the same family, through three generations. Ekmans description of the condition mentioned dwarfism, bone fragility, and bowing of the long bones. : 763  In 1831, Edmund Axmann gave a detailed description of it in himself and his two brothers, being the first to mention blue sclerae as a characteristic sign of OI. : 683  Jean Lobstein first described the mild form of the condition, today known as type I, in 1833, calling it "osteopsathyrosis idiopathica". : 347 It was not until 1912 that hearing loss was positively recognized as a symptom of OI, first mentioned in a brief paper by the English physician Charles Allen Adair-Dighton.
Brittle asthma is a type of asthma distinguishable from other forms by recurrent, severe attacks. There are two subtypes divided by symptoms: Type 1 and Type 2, depending on the stability of the patients maximum speed of expiration, or peak expiratory flow rate (PEFR). Type 1 is characterized by a maintained wide PEF variability despite considerable medical therapy including a dose of inhaled steroids, and Type 2 is characterized by sudden acute attacks occurring in less than three hours without an obvious trigger on a background of well controlled asthma.Brittle asthma is one of the "unstable" subtypes of "difficult asthma", a term used to characterize the less than 5% of asthma cases that do not respond to maximal inhaled treatment, including high doses of corticosteroids combined with additional therapies such as long-acting beta-2 agonists. Diagnosis
Types
The 2005 Oxford Textbook of Medicine distinguishes type 1 brittle asthma by "persistent daily chaotic variability in peak flow (usually greater than 40 per cent diurnal variation in PEFR more than 50 per cent of the time)", while type 2 is identified by "sporadic sudden falls in PEFR against a background of usually well-controlled asthma with normal or near normal lung function". In both types, patients are subject to recurrent, severe attacks. The cardinal symptoms of an asthma attack are shortness of breath (dyspnea), wheezing, and chest tightness.