Table 1.
Study cohort characteristics obtained through review of medical records and parent survey responses
| Age (Years) | Sex | ALPL variant confirmed by molecular testing | Low alkaline phosphatase | Elevated vitamin B6 | Clinical findings of HPP** | Asfotase alfa therapy | Duration of asfotase alfa therapy prior to enrollment | Mental health diagnoses*** |
|---|---|---|---|---|---|---|---|---|
| 3 | F | c.1250A>G | X | PTL, SS | ||||
| 3.5 | M | Not tested | X | X | PTL, SS | X | 2 years | |
| 4 | M | Not tested | X | X | PTL, C, MW, AG | X | 2 years | OCD, sensory processing disorder |
| 4.4 | F | c.1259G>C | X | X | PTL | |||
| 4.6 | M | c.892G>A | X | |||||
| 4.9 | F | c.1133A>T | X | X | PTL | |||
| 5.3 | M | c.407G>A; c.984_986delCTT; *c.818C>T | X | PTL, SS | X | 1 year | ||
| 5.5 | F | Not available | X | PTL, C, MW | X | 2 years (tapered off) | ||
| 5.6 | F | c.1133A>T | X | PTL, LBMD, SS | Anxiety | |||
| 5.6 | F | c.1171delC; c.406C>T | PTL, SS, BLB, R, MW, AG | X | 5.5 years | |||
| 5.8 | F | c.1133A>T | X | X | PTL, BLB | |||
| 5.9 | F | c.407G>A; *c.1213>C | X | X | PTL, SS, BLB, R, MW, AG | X | 2 years | |
| 5.9 | M | c.1133A>T | X | X | PTL, LBMD | Anxiety | ||
| 6 | F | c.1471G>A; *c.1327G>T | X | PTL, C, CD, BLB | X | 4 years | ||
| 6.2 | M | c.1133A>T | X | X | PTL | |||
| 6.6 | M | c.881A>C | X | SS, CD, MW | Autism spectrum disorder | |||
| 7.7 | M | c.1142A>G | X | PTL | Depression, disruptive behavior | |||
| 7.7 | M | c.976G>C | X | SS | Dyslexia | |||
| 7.9 | F | c.571G>A | PTL | |||||
| 8 | F | Not available | X | PTL, CD, BLB, MW, AG | X | 2.6 years | ||
| 8.8 | F | c.920C>T; c.1171C>T | PTL, LBMD, SS, CD, BLB, F, R, C, MW, AG | X | 8.5 years | |||
| 9.5 | M | c.346G>A; c.571G>A | PTL, LBMD, CD, R, MW, AG | X | 2.6 years | |||
| 10.4 | M | c.1250A>G | X | X | PTL, MW | |||
| 10.5 | M | *c.1157G>A | X | F, MW, AG | ADHD, disruptive behavior | |||
| 13.2 | M | Not available | X | PTL, SS, CD, BLB, R, C, MW, AG | X | 8 years | ||
| 13.3 | M | c.340G>A | X | PTL, F, AG | X | Not available | ADHD, OCD, anxiety | |
| 13.6 | M | Not available | X | PTL, BLB, F, R, MW, AG | X | 0.8 year | ||
| 13.6 | F | Not available | X | X | PTL, SS, CD, BLB, R, MW, AG | X | 6 years | |
| 15.4 | M | Not tested | X | X | PTL, LBMD, R, MW, AG | X | 1.6 years | Depression, dyslexia |
| 16.6 | F | c.526G>A; *c.371A>G | X | X | PTL, MW, AG |
*Variant of uncertain significance
**Clinical findings of HPP. PTL premature tooth loss, LBMD low bone mineral density/osteopenia, SS short stature, CD chest deformity, BLB bowing of the long bones, R ricket-like bone findings on x-ray, F recurrent or poorly healing fractures, C craniosynostosis, MW muscle weakness, AG abnormal gait
***Mental health diagnosis confirmed by medical documentation. ADHD attention deficit hyperactivity disorder, OCD obsessive–compulsive disorder