Table 1.
Clinical and laboratory characteristics
| Characteristics | All Patients (n=122) |
|---|---|
| Age, yr | 62.7±13.5 |
| Symptomatic carriers/asymptomatic carriersa | 68/54 |
| Body mass index, kg/cm2 | 25±4.6 |
| Women, n (%) | 96 (80) |
| Hypertension, n (%) | 65 (56) |
| Diabetes, n (%) | 4 (3.5) |
| PEPT2 genotype, n (%) | |
| *1/*1 (exon 13b CC/exon 15 CC) | 26 (21.5) |
| *1/*2 (exon 13b CT/exon 15 CT) | 62 (51) |
| *2/*2 (exon 13b TT/exon 15 TT) | 32 (26) |
| *1/*3 (exon 13b CC/exon 15 TT) | 2 (1.5) |
| HMBS mutation, % null allele/missense | 71/29 |
| Urine ALA-to-creatinine ratio, μmol/mmol creatinineb | 5.1±4.7 |
| Symptomatic carriers | 6±5.3 |
| Asymptomatic carriers | 3.9±3.7 |
| Urine PBG-to-creatinine ratio, μmol/mmol creatininec | 5.8±7.1 |
| Symptomatic carriers | 7.7±7.9 |
| Asymptomatic carriers | 3.5±5 |
| eGFR, ml/min per 1.73 m2 | 67±23.7 |
| Urine protein-to-creatinine ratio, g/mmol creatinine | 0.06±0.09 |
Values are means±SD unless otherwise indicated. The GFR was estimated according to the four-variable Modification of Diet in Renal Disease formula.
“Symptomatic carrier” is defined as the association of at least one AIP attack with a typical porphyrin and heme precursor excretion profile in both urines and feces, confirmed by a 50% decrease in HMBS activity in erythrocytes and the identification of a causative mutation in the HMBS gene. “Asymptomatic carrier” status is defined after a family screening to identify those with latent disease and on the basis of a deficient HMBS enzymatic activity, and confirmed with a DNA analysis by direct sequencing to identify the causative mutation in the HMBS gene.
ALA-to-creatinine normal value <3 µmol/mmol creatinine.
PBG-to-creatinine normal value <1 µmol/mmol creatinine.