OBJECTIVETo study the difference of plasma actual bicarbonate between the children with growth hormone deficiency (GHD) and idopathatic short stature (ISS) and to value the plasma bicarbonate standard deviation scores (SDS) in diagnosis of GHD.

METHODSForty-seven short stature children were divided into two groups (GHD and ISS) according to the peak GH response to provocative test. Plasma actual bicarbonate concentrations anion gap (AG), base excess and electrolytes were measured in 47 children with short stature before GH provocative tests.

RESULTSThe mean plasma actual bicarbonate concentrations, bicarbonate SDS were (22.60+/-1.29)mmol/L and -0.27+/-0.98 respectively in GHD children, which were significantly lower than those of ISS children (P<0.01), whereas AG was higher than that of ISS children [(11.73+/-4.52 vs 7.87+/-1.70) mmol/L], P<0.01. Seventy-two percent of patients with bicarbonate SDS

CONCLUSIONPlasma actual bicarbonate concentrations and bicarbonate SDS are lower in patients with GHD than those in patients with idopathatic short stature. Evaluation of plasma bicarbonate SDS of short stature children can predict the probability of GHD, especially when bicarbonate SDS is less than 1 s.