Ljiljana Popović

Pseudocholinesterase activity in cerebrospinal fluid as a biomarker of solid central nervous system tumors in children.

Aim To determine the activity of pseudocholinesterase (PChE) in cerebrospinal fluid (CSF) and serum in children with solid central nervous system (CNS) tumor and to assess whether PChE activity could be a valid biomarker for solid CNS tumors in children. Methods The study and control group included 30 children each. Children in the study group had a solid CNS tumor, while those from the control group had never suffered from any tumor diseases. CSF and serum samples were collected from all participants and PChE activity was determined using the Ellman’s spectrophotometric method. PChE activity in CSF was shown as a cerebrospinal fluid/serum ratio expressed in percentage, ie, PChE CSF/serum ratio. Receiver operating characteristic (ROC) curve was used to assess whether PChE activity can be used as a biomarker for identifying children with solid CNS tumors. Results Children with solid CNS tumor had significantly higher PChE activity in CSF and serum, as well as PChE CSF/serum ratio (P = 0.001). PChE CSF/serum ratio in the study group was 2.38% (interquartile range [IQR] 1.14-3.97) and 1.09% (IQR 0.95-1.45) in the control group. ROC curve analysis of PChE CSF/serum ratio resulted in an area under the curve (AUC) value of 0.76 (95% confidence interval [CI] 0.63-0.88) and a cut-off of 1.09. Twenty five of 29 patients with elevated PChE CSF/serum ratio had a tumor, corresponding to a sensitivity of 83% and a specificity of 53%. Conclusion PChE CSF/serum ratio may be used as a test or biomarker with good sensitivity for solid CNS tumors in children.

Successful Early Pyeloplasty in Infants

BACKGROUND Early pyeloplasty for the treatment of congenital ureteropelvic junction obstruction to maximize nephron salvage is justified only if potential hazards of operating on small infants are avoided. METHODS The records were analyzed of all infants who underwent pyeloplasty over a 5-year period. Open pyeloplasty was performed if collecting systems had deteriorated or were demonstrated to be obstructed; it was also performed for severe cases of hydronephrosis. Outcome of surgery in the younger infant (patients <2 months of age) was compared with the older infant group (patients >2 months of age). Preoperative evaluation in case of mild or moderate hydronephrosis was directed toward ruling out a non-obstructed collection system and included voiding cystourethrography, and serial ultrasonography and/or dual isotope diuretic renography. Postoperative assessment consisted of serial ultrasonography and/or nuclear imaging to confirm decompression and relief of obstruction. RESULTS A total of 24 pyeloplasties were performed on 22 patients in the younger infant group (two bilateral) and 30 were performed on 27 infants in the older infant group (three bilateral). The only significant differences between the groups were as follows: patients in the younger infant group were likely to present in utero (75%, p = 2.69), whereas those in the older infant group were more likely to present with a urinary tract infection (48%, p = 4.12). During follow-up examination, 23 renal units in the younger infant group and 24 in the older infant group were judged to be stable or improved. Four kidneys were not salvaged after pyeloplasty, one in the younger infant group and three in the older infant group. CONCLUSIONS Good results of pyeloplasties performed in the infants in this series support early correction of ureteropelvic junction obstruction in infants.