| Patient | Sex | First acute episode | Subsequent clinical progress | Family history | Age | Presenting symptoms | Blood ammonia (first measurement - maximum value, μmol/l, N.R. 50–80) | Therapy received | Outcome |
| 1 | M | 3d | Poor suck, reduced oral intake and lethargy progressing to coma | 350 -780 | Stop protein intake, PFN, SB, SPB, L-Arg, PD, MV | Survived | Spastic tetraplegia, severe psychomotor retardation, frequent hyperammonemic episodes despite a low-protein diet and treatment with oral ammonia scavengers, fatal encephalopathy at 6 y | Negative |
| 2 | F | 6y | Recurrent vomiting, difficulty in breathing following a febrile illness | 215 - 310 | iv SB, SPB, L-Arg, | Survived | Mild learning disability, infrequent decompensation on a low-protein diet and oral ammonia scavengers | A younger male sibling died of hyperammonemic coma at 40d |
| 3 | M | 2d | Poor feeding, lethargy, tachypnea, irritability, coma | 305 - 850 | Stop protein intake, PFN, PD, MV | Died | - | Negative |
| 4 | F | 7d | Feeding intolerance, irritability, altered sensorium | 250 - 480 | Stop protein intake, PFN, SB, SPB, L-Arg, PD, MV | Survived | Moderate developmental delay/learning disability, recurrent decompensation | Negative |
| 5 | M | 5d | Sudden onset of fits, progressing to somnolence and coma and respiratory arrest | 450 – 2,361 | Stop protein intake, PFN, MV | Died | - | A male sibling died suddenly during neonatal period (undiagnosed) |
| 6 | M | 2d | Feeding refusal, vomiting, lethargy, progressing to coma | 750 - 865 | Stop protein intake, PFN, MV | Died | - | Negative |
| 7 | M | 3d | Poor suck, lethargy, hypotonia, coma | 345 – 2,915 | Stop protein intake, PFN, PD, MV | Died | - | Negative |
| 8 | F | 1y | History of failure to thrive, hypotonia, seizures. Acute encephalopathy and respiratory distress following a febrile illness. | 236 - 560 | Stop protein intake, PFN, phenytoin, MV | Died | - | Multiple neonatal deaths among maternal male siblings |
| 9 | M | 5d | Vomiting, lethargy, seizures, progressing to coma | 201 - 990 | Stop protein intake, PFN, SB, SPB, L-Arg, PD, MV | Died | - | Negative |
| 10 | M | 2d | Poor suck, vomiting, progressive lethargy, and irritability | 320 - 980 | Stop protein intake, PFN, MV | Died | - | Negative |
| 11 | M | 2d | Lethargy, poor breathing effort, progressing to cardiorespiratory collapse | 1,700 | Stop protein intake, PFN, MV | Died | - | Multiple neonatal deaths among maternal male siblings |
| 12 | M | 2d | Poor oral intake and lethargy progressing to coma | 468 - 789 | Stop protein intake, PFN, SB, SPB, L-Arg, PD, MV | Survived | Severe psychomotor retardation, frequent hyperammonemic episodes despite a low-protein diet and treatment with oral ammonia scavengers, fatal encephalopathy at 2y | Negative |
| 13 | M | 2d | Reduced oral intake, lethargy, irritability, progressing to coma | 248 – 1,065 | Stop protein intake, PFN, SB, SPB, L-Arg, CVVH, MV | Survived | Mild psychomotor retardation, infrequent hyperammonemic episodes on low-protein diet and oral ammonia scavengers | Negative |
| 14 | M | 2d | Poor suck, lethargy, abnormal breathing, progressing to coma | 332 - 976 | Stop protein intake, PFN, SB, SPB, L-Arg, MV | Died | - | First one diagnosed in the family |
| 15 | F | 14y | Vomiting, seizures and progressive acute encephalopathy following a febrile illness | Not done | PFN, phenytoin, antibiotics, MV | Died | - | Sibling of Patient 14 (They presented around the same time.) |
| 16 | F | 34y | History of protein avoidance. Post-partum delirium | 180 - 250 | Stop protein intake, PFN, high calories intake, SB, SPB, L-Arg | Survived | Mildly symptomatic. Nausea if consuming high protein content foods | Mother of Patients 14 and 15 |
|
|