Table 1.

Clinical and biochemical features of primary renal tubular acidosis (RTA) affecting the distal nephron

Dominant dRTARecessive dRTAOsteopetrosis with RTA
a After bicarbonate replacement.
b Gene symbols for the ATP6 family have been changed ( ATP6V1B1 replaces ATP6B1; ATP6V0A4replaces ATP6N1B.
Usual presentationOlder/adultInfancy/early childhoodChildhood
Symptoms/signsNone?Early nephrocalcinosisEarly nephrocalcinosis
NephrolithiasisVomiting/dehydrationThickened bones
NephrocalcinosisPoor growthCerebral calcification
Sometimes ricketsRicketsMental retardation
Sometimes osteomalaciaBilateral SNHL in about 1/3, usually severeDeafness
Hematology2° erythrocytosisAnemia
BiochemistryMild or compensated hyperchloraemic acidosisSevere hyperchloraemic acidosisHyperchloraemic acidosis
Low/normal KLow KLow K
Urine chemistryMin urine pH > 5.5Min urine pH > 5.5Min urine pH < 5.5a
Low urine citrateLow urine citrate
Low urine ammoniumLow urine ammonium
Low urine-blood pCO2Low urine-blood pCO2High urine-blood pCO2
TreatmentCitrate/bicarbonateCitrate/bicarbonateHigh dose citrate/bicarbonate
Marrow/stem cell transplantation
Gene(s) and proteinbSLC4A1: AE1ATP6V1B1: H+-ATPase B1 subunitCA2: Carbonic anhydrase II
ATP6V0A4: H+-ATPase a4 subunit rarely SLC4A1: AE1