ABSTRACT
A kinetic assay for total calcium in serum was developed which is based on the activation of Ca++-ATPase by free Ca++ [Ca++]f maintained by EGTA in the reaction mixture. The concentration of Caf++ was dependent on total reference calcium added or serum calcium. Ca++-ATPase activity was coupled to the reduction of NADH by pyruvate kinase (PK) and lactate dehydrogenase (LDH) and monitored by change in absorbance at 340 nm. The calcium in normal serum was 10.08 +/- 0.24 mg/ dl (n = 35) by our method while with o-cresolphthalein complexone (CPC) method, the total calcium in the same 35 serum samples was 10.14 +/- 0.54 mg/dl. The range of within-run coefficient of variations (CVs) by this method was 0.9-2.87% at 8-12 mg/dl and day-to-day CVs were 0.72-3.17%. The presence of other ions and standard clinical interfering agents did not affect this assay system. The correlation between values obtained with our method (y) and CPC method (x) for normal serum was: y = 1.064x-0.580 mg/dl (r = 0.912, n = 59).
Subject(s)
Adolescent , Adult , Female , Humans , Male , Adenosine Triphosphatases/metabolism , Calcium/blood , Comparative Study , Enzyme Activation , Kinetics , NAD/metabolism , Pyruvate Kinase/metabolism , Reference Standards , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Eighty five children with recurrent abdominal pain(RAP) were studied. Organic cause was noticed in 70 cases and non-organic in 15 cases. Giardiasis was the commonest organic cause in 57 (67.0 percent), either alone or with other parasitic infestations. Other organic causes include gallstones (4.7 percent), urinary infections (4.7 percent), esophagitis/gastritis (3.5 percent) and abdominal tuberculosis (2.3 percent). Single parent, school phobia, sibling rivalry, RAP in other family members and nocturnal enuresis are significant factors associated with nonorganic causes