PMID- 9323296
OWN - NLM
STAT- MEDLINE
DCOM- 19971119
LR  - 20190905
IS  - 0931-041X (Print)
IS  - 0931-041X (Linking)
VI  - 11
IP  - 5
DP  - 1997 Oct
TI  - Renal tubular acidosis and osteopetrosis with carbonic anhydrase II deficiency: 
      pathogenesis of impaired acidification.
PG  - 633-6
AB  - Renal tubular acidosis with osteopetrosis is an autosomal recessive disorder due 
      to deficiency of carbonic anhydrase II (CAII). A 3.5-year-old Egyptian boy with 
      osteopetrosis and cerebral calcification has a persistent normal anion gap type 
      of metabolic acidosis (plasma pH 7.26) and a mild degree of hypokalemia. A 
      baseline urine pH was 7.0; ammonium (NH4+) excretion was low at 11 mumol/min per 
      1.73 m2; fractional excretion of bicarbonate HCO3 (FEHCO3) was high at 9% when 
      plasma HCO3 was 20 mmol/l; citrate excretion rate was high for the degree of 
      acidosis at 0.35 mmol/mmol creatinine. Intravenous administration of sodium 
      bicarbonate led to a urine pH of 7.6, a FEHCO3 of 14%, a urine-blood PCO2 
      difference of 7 mmHg, NH4+ excretion fell to close to nil, and citrate excretion 
      remained at 0.38 mmol/mmol creatinine. Intravenous administration of arginine 
      hydrochloride caused the urine pH to fall to 5.8, the FEHCO3 to fall to 0, the 
      NH4+ excretion rate to rise to 43 mumol/min per 1.73 m2, and citrate excretion to 
      fall to < 0.01 mmol/mmol creatinine. These results show that our patient had a 
      low rate of NH4+ excretion, a low urine minus blood PCO2 difference in alkaline 
      urine, and a low urinary citrate excretion, but only when he was severely 
      acidotic. He failed to achieve a maximally low urine pH. These findings indicate 
      that his renal acidification mechanisms were impaired in both the proximal and 
      distal tubule, the result of his CAII deficiency.
FAU - Nagai, R
AU  - Nagai R
AD  - Department of Pediatrics, University of Toronto, Canada.
FAU - Kooh, S W
AU  - Kooh SW
FAU - Balfe, J W
AU  - Balfe JW
FAU - Fenton, T
AU  - Fenton T
FAU - Halperin, M L
AU  - Halperin ML
LA  - eng
PT  - Case Reports
PT  - Journal Article
PL  - Germany
TA  - Pediatr Nephrol
JT  - Pediatric nephrology (Berlin, Germany)
JID - 8708728
RN  - 0 (Bicarbonates)
RN  - 7664-41-7 (Ammonia)
RN  - EC 4.2.1.1 (Carbonic Anhydrases)
SB  - IM
CIN - Pediatr Nephrol. 1998 Apr;12(3):261. PMID: 9630052
CIN - Pediatr Nephrol. 1999 Feb;13(2):180. PMID: 10229010
MH  - Acidosis, Renal Tubular/blood/*enzymology/*pathology
MH  - Ammonia/urine
MH  - Bicarbonates/metabolism
MH  - Carbonic Anhydrases/blood/*deficiency
MH  - Erythrocytes/enzymology
MH  - Humans
MH  - Infant
MH  - Male
MH  - Osteopetrosis/blood/*enzymology/*pathology
EDAT- 1997/11/05 00:00
MHDA- 1997/11/05 00:01
CRDT- 1997/11/05 00:00
PHST- 1997/11/05 00:00 [pubmed]
PHST- 1997/11/05 00:01 [medline]
PHST- 1997/11/05 00:00 [entrez]
AID - 10.1007/s004670050354 [doi]
PST - ppublish
SO  - Pediatr Nephrol. 1997 Oct;11(5):633-6. doi: 10.1007/s004670050354.