Table 2.
Initial treatment with arginine and/or citrulline after diagnosis and during follow up (exposed population)
| OTC (n = 57) | CPS1 (n = 15) | NAGS (n = 4) | ORNT1 (n = 3) | Total (n = 79) | |
|---|---|---|---|---|---|
| Initial treatment after diagnosis, n (%) | |||||
| Arginine | 35 (61.4) | 6 (40.0) | 3 (75.0) | 2 (66.7) | 46 (58.2) |
| Citrulline | 11 (19.3) | 1 (6.7) | 1 (25.0) | 1 (33.3) | 14 (17.7) |
| Arginine + citrulline | 11 (19.3) | 8 (53.3) | 0 | 0 | 19 (24.1) |
| Duration of exposure to initial treatment, years, median (range) | |||||
| Arginine and/or citrulline | 0.7 (0.0–23.9) | 0.9 (0.0–15.4) | 0.8 (0.0–6.9) | 2.5 (1.9–9.1) | 0.9 (0.0–23.9) |
| Arginine | 0.3 (0.0–23.9) | 0.2 (0.0–6.9) | 0.2 (0.0–1.4) | 5.5 (1.9–9.1) | 0.3 (0.0–23.9) |
| Citrulline | 2.5 (0.0–19.2) | 0.6 (0.6–0.6) | 6.9 (6.9–6.9) | 2.5 (2.5–2.5) | 2.5 (0.0–19.2) |
| Arginine + citrulline | 3.6 (0.1–18.8) | 8.9 (0.2–15.4) | – | – | 5.5 (0.1–18.8) |
| Received any time during follow up, n (%) | |||||
| Arginine (± citrulline) | 48 (84.2) | 15 (100) | 3 (75.0) | 2 (66.7) | 68 (86.1) |
| Citrulline (± arginine) | 49 (86.0) | 14 (93.3) | 3 (75.0) | 2 (66.7) | 68 (86.1) |
| Received only arginine during follow up, n (%) | 8 (14.0) | 1 (6.7) | 1 (25.0) | 1 (33.3) | 11 (13.9) |
| Received only citrulline during follow up, n (%) | 9 (15.8) | 0 | 1 (25.0) | 1 (33.3) | 11 (13.9) |
| Received only arginine + citrulline during follow up, n (%) | 4 (7.0) | 6 (40.0) | 0 | 0 | 10 (12.7) |
| Received only arginine at least once during follow up, n (%) | 38 (66.7) | 6 (40.0) | 3 (75.0) | 2 (66.7) | 49 (62.0) |
| Received only citrulline at least once during follow up, n (%) | 22 (38.6) | 5 (33.3) | 2 (50.0) | 1 (33.3) | 30 (38.0) |
| Received arginine + citrulline at least once during follow up, n (%) | 38 (66.7) | 13 (86.7) | 2 (50.0) | 1 (33.3) | 54 (68.4) |
| Time from diagnosis to first treatment with arginine and/or citrulline, years | |||||
| Arginine | |||||
| Mean (SD) | 1.9 (5.3) | 0.1 (0.1) | 0.1 (0.2) | 0.1 (0.1) | 1.5 (4.7) |
| Median (range) | 0.0 (0.0–25.9) | 0.0 (0.0–0.3) | 0.0 (0.0–0.3) | 0.1 (0.0–0.2) | 0.0 (0.0–25.9) |
| Citrulline | |||||
| Mean (SD) | 2.9 (3.5) | 4.1 (6.6) | 1.4 (1.0) | 0.1 (NA) | 2.9 (3.9) |
| Median (range) | 1.4 (0.0–11.5) | 0.4 (0.4–15.6) | 1.4 (0.7–2.2) | 0.1 (0.1–0.1) | 1.2 (0.0–15.6) |
| Arginine + citrulline | |||||
| Mean (SD) | 2.4 (5.4) | 0.2 (0.4) | 0.1 (0.1) | 9.2 (NA) | 1.9 (4.7) |
| Median (range) | 0.1 (0.0–25.6) | 0.0 (-0.1–1.1)a | 0.1 (0.0–0.2) | 9.2 (9.2–9.2) | 0.0 (-0.1–25.6) |
| Duration of exposure, years, median (range) | |||||
| Arginine and/or citrulline | 9.4 (0.5–25.7) | 9.1 (0.2–28.4) | 3.0 (1.4–6.9) | 2.5 (1.9–35.2) | 7.3 (0.2–35.2) |
| Arginine monotherapy | 0.6 (0.0–23.9) | 0.2 (0.0–6.9) | 1.4 (0.2–2.7) | 5.5 (1.9–9.1) | 0.6 (0.0–23.9) |
| Citrulline monotherapy | 3.7 (0.0–19.2) | 3.2 (2.0–12.0) | 3.5 (0.0–6.9) | 2.5 (2.5–2.5) | 3.1 (0.0–19.2) |
| Arginine + citrulline | 5.2 (0.1–22.9) | 9.5 (0.2–15.7) | 1.5 (1.1–2.0) | 26.2 (26.2–26.2) | 5.9 (0.1–26.2) |
| Duration of exposure as a percentage of total follow up duration, median (range) | |||||
| Arginine and/or citrulline | 99.8 (7.4–100.0) | 99.8 (82.8–100.0) | 57.8 (26.6–99.9) | 98.7 (96.8–99.6) | 99.8 (7.4–100.0) |
| Arginine monotherapy | 6.2 (0.0–100.0) | 2.1 (0.1–96.1) | 72.3 (1.9–81.6) | 62.2 (25.6–98.7) | 7.4 (0.0–100.0) |
| Citrulline monotherapy | 59.6 (0.2–100.0) | 41.9 (17.0–94.0) | 17.1 (0.3–33.9) | 96.8 (96.8–96.8) | 55.7 (0.2–100.0) |
| Arginine + citrulline | 94.3 (0.5–100.0) | 99.1 (6.0–100.0) | 26.0 (24.5–27.6) | 73.9 (73.9–73.9) | 94.3 (0.5–100.0) |
aOne patient was treated for suspected UCD before diagnosis was confirmed
CPS1, carbamoyl phosphate synthetase 1; NAGS, N-acetylglutamate synthase; NA, not applicable; ORNT1, ornithine translocase; OTC, ornithine transcarbamylase; SD, standard deviation; UCD, urea cycle disorders