Table 2.
Follow-up data on infants with definite or “possible” Pompe disease.
| Case | Genotype | Phenotype | GAA Activity a Result (nl) | CK (IU/L) Result (nl) |
Urine Glc4 or Hex4 b Result (nl) |
Cardiac Findings | Other Clinical Findings |
|---|---|---|---|---|---|---|---|
| 1 | c.2560C>T, c.1211A>T, c.2161G>C | IOPD | 0.02 (>3.0) | 1064 (35–232) |
NR | HCM | Hypotonia |
| 2 | c.1437+1G>A, c.2227C>T | IOPD | 0.8 (>3.88) | 566 (32–250) |
NR | HCM | Hypotonia; Motor delay |
| 3 | c.2560C>T, c.2459_2461del | IOPD | 1.6 (>3.88) | 3488 (30–279) |
Glc4 14.9 (0.14–1.29) |
HCM | Initial hypotonia c |
| 4–16 | c.-32-13T>G homozygous | LOPD | 0.0–2.8 | 153–669 (8/17 elevated) |
See footnote d | Normal e | None |
| 17 | c.-32-13T>G, c.1655T>C | LOPD | 0.8 (>3.0) | 550 | Normal | ASD | Mild hypotonia |
| 18 | c.-32-13T>G, c.2238G>C | LOPD | 2.55 (>3.88) | 86 (29–168) | Normal | None | None |
| 19 | c.-32-13T>G, c.1839G>A | LOPD | 1.5 (>3.88) | 641 (30–279) | Glc4 7.59 (0.14–1.29) |
None | None |
| 20 | c.-32-13T>G, c.258DPC | LOPD | 0.3 (>3.0) | NR | NR | None | None |
| 21 | c.-32-13T>G, c.2238G>C, c.2065G>A | LOPD | 1.0 (>3.0) | NR | Hex4 41.6 (<20) |
RVH on ECG; PFO on echo | None |
| 22 | c.-32-13T>G, c.2297A>G | LOPD f | 2.3 (>3.88) | 168 (55–170) | Glc4 1.21 (0.08–1.37) | Normal | None |
| 23 | c.307T>G, c.1375G>C, c.271G>A | LOPD f | 1.6 (>3.88) | Normal | Glc4 2.0 (1.14–1.29) | Normal | None |
| 24 | c.1637-3_1637-4delinsG, c.1831G>A | LOPD | 2.4 (>3.88) | 93 (30–279) | Glc4 12.98 (0.14–1.29) | Normal | None |
| 25 | c.-32-12T>G, c.2219-2220delTG | LOPD g | 2.0 (>3.88) | 555 (30–279) | Glc4 11.79 (0.14–1.29) | PFO | Hypotonia; gross motor delay |
| 26 | c.2238G>C, c.2242dupG | LOPD f | 2.9 (>3.88) | 142 (30–279) | Glc4 6.54 (0.14–1.29) | Normal | None |
| 27 | c.2173delC, c.858+17-858+23delCGGGGCGG | LOPD | 2.9 (>3.88) | 272 (30–279) | NR | Normal | None |
| 28 | c.1121G>T, c.885C>T | LOPD | 0.3 (>3.0) | NR | NR | Normal | None |
| 29 | c.307T>G, c.525delT | LOPD | 0.5 (>3.0) | 193 (55–170) | NR | Normal | None |
| 30 | c.655G>A, c.1418G>C | UND | 3.0 (>7.4) | 73 (39–308) | Hex4 11.2 (<20) | PFO | None |
| 31 | c.525delT, c.265C>T | UND f | 2.9 (>3.88) | 74 (30–279) | Glc4 6.76 (0.14–1.29) | PFO h | None |
| 32 | c.1942G>A, c.1346C>T, c.2065G>A, c.1726G>A | UND | 0.2 (>3.0) | 167 (39–308) | NR | Normal | None |
| 33 | c.664G>A, c.1346C>T | UND | 0.0 (>3.88) | 101 (30–279) | NR | Normal | None |
| 34 | c.726G>A, c.1357G>A | UND | 0.7 (>3.0) | NR | NR | Normal | None |
| 35 | c.1631T>A, c.2509C>T, c.2065G>A | UND | UND | 0.7 (>3.0) | NR | NR | Normal |
| 36 | c.307T>G, c.265C>T | UND | 2.1 (>3.88) | 152 (30–279) | NR | NR | Normal |
| 37 | c.1781G>A, c.1194+3G>C | UND | 3.5 (>3.88) | 571 (30–279) | Glc4 3.46 (0.14–1.29) | Normal | None |
a GAA activity units: pmol/punch/h. b Urine Glc4 or Hex4 activity units: mmol/mol creatinine. c Initial hypotonia and hypoventilation during sleep; resolved by 10 months of age. d 13 Cases: NR for 7; Glc4 5.42–9.83 (0.142–1.29) for 4; Hex4 6.8 and 13.2 (<20) for 2. e One case with left ventricular hypertrophy on ECG, with normal echo; all others normal. f Older sibling, born prior to newborn screening, has same genotype. g Symptomatic at 9 months of age, started on ERT. h Also had mildly dilated ascending aorta. ASD = Atrial septal defect. CK = creatine kinase. GAA activity = dried blood spot alpha-glucosidase activity determined at time of diagnostic evaluation. Glc4 = glucose tetrasaccharide. HCM = Hypertrophic cardiomyopathy. Hex4 = hexose tetrasaccharide. IOPD = Infantile onset Pompe disease. LOPD = Late onset Pompe disease. nl = Normal. NR = Not reported. PFO = Patent foramen ovale. RVH = Right ventricular hypertrophy. UND = Undetermined.