Figure 2.

Residual enzymatic ASS1 activity predicts number and severity of HAEs. (A) Number of HAEs (NH₄ ⁺ _max ≥ 100 µmol/L) per year subject to residual enzymatic ASS1 activity (%). Each point represents a single patient (n = 43). Gray line displays estimated regression curve. GAM‐analysis, P = 0.002, R ² = 0.26. (B) Boxplot illustrating number of HAEs (NH₄ ⁺ _max ≥ 100 µmol/L) per year with a residual enzymatic ASS1 activity below or equal to 8.1% (n = 17) or above 8.1% (n = 26). Data are shown as median (black thick line) and mean (triangle), length of the box corresponds to IQR, upper and lower whiskers correspond to max. 1.5 × IQR, each point represents an outlier. Recursive partitioning, P = 0.003. (C) NH₄ ⁺ _max during most severe HAE subject to residual enzymatic ASS1 activity (%). Each point represents a single patient (n = 26). Gray line displays estimated regression curve. GAM‐analysis, P = 0.007, R ² = 0.23. (D) Boxplot illustrating NH₄ ⁺ _max during most severe HAE with a residual enzymatic ASS1 activity below or equal to 8.1% (n = 17) or above 8.1% (n = 9). Data are shown as median (black thick line) and mean (triangle), length of the box corresponds to IQR, upper and lower whiskers correspond to max. 1.5 × IQR, each point represents an outlier. Recursive partitioning, P = 0.01. ASS1, argininosuccinate synthetase 1.