As an acuteA condition or illness that usually has a rapid onset of symptoms and may resolve within days with or without treatment. It is the opposite of chronic. phase protein, the serum level of A1AT fluctuates over time, notably increasing during acuteA condition or illness that usually has a rapid onset of symptoms and may resolve within days with or without treatment. It is the opposite of chronic. inflammation [61], and the test-retest reproducibility of this measurement is weak. This makes it problematic to properly classify individuals regarding their A1AT deficiency status, particularly in situations of intermediate deficits. To account for the intrinsic variability of the measurement, a cut-off of < 23 μmol/L (< 1.2 g/L) is proposed above which most patients with A1AT deficiency should be reasonably excluded, therefore not mandating further testing. This cut-off may be applied in many clinical situations, such as in individuals with a diagnosis of COPD, unexplained bronchiectasis or adult-onset asthma with persistent airway obstruction, although some authors have suggested a higher threshold considering that levels as high as 1.4 g/L may be reached in some patients with A1AT deficiency during episodes of acuteA condition or illness that usually has a rapid onset of symptoms and may resolve within days with or without treatment. It is the opposite of chronic. inflammation.
Alpha-1-Antitrypsin Deficiency Targeted Testing and Augmentation Therapy: A Canadian Thoracic Society Meta-analysis and Clinical Practice Guideline – Canadian Journal of Respiratory, Critical Care, and Sleep Medicine