[Usefulness of serum procalcitonin in the early diagnosis of maternal-fetal bacterial infection. A prospective study]

Early diagnosis avoiding unnecessary treatment of maternal-fetal bacterial infection remains one of the greatest challenges for obstetricians and pediatricians. To meet these objectives, many inflammatory mediators were used, including procalcitonin (PCT). The aim of our study was to determine the usefulness of PCT in early diagnosis and management of neonatal infection.

SUBJECTS AND METHODS

Over a period of 8 months, all living newborns with highly suspected maternal-fetal bacterial infection who were to receive antibiotic treatment according to our neonatal unit protocol were included in this prospective study. Serum PCT concentrations were determined at birth and after 12h of life using a specific immunoluminometric assay. Two distinct populations were defined based on clinical, biological, and bacteriological criteria: group 1: infected neonates, and group 2: noninfected neonates.

STATISTICAL METHODS

We compared PCT means in different groups and determined the cut-off value correlated with maternal-fetal bacterial infection by analyzing the receiver operating characteristics curve (ROC).

RESULTS

A total of 130 neonates were included in the study: 38 (29%) were classified in group 1 with 29 possible infections and 9 defined infections, including 5 cases of septicemia. The average PCT at birth in group 1 was significantly higher than in group 2 (3.52 ± 8.19 ng/ml vs 0.43 ± 0.73 ng/ml; P<0.001). The PCT threshold value at birth found by the ROC curve with the highest sensitivity (71.1%) and highest specificity (62%) was 0.215 ng/ml. The negative predictive value (NPV) was 83.8%, making it possible to avoid unnecessary treatment in the majority of the cases. The PCT threshold value within 12h of birth was 3.78 ng/ml, for a sensitivity of 89.5% and 1 NPV of 94.4%.

CONCLUSION

PCT is a valuable biological examination because it can be administered early, it is sensitive, and it has a NPV. These characteristics make PCT a biological argument that can be used in the initial decision on whether to administer antibiotics. Another study will be conducted to establish the cut-off value.

[Biochemical and molecular diagnosis of primary hyperoxaluria type 1: Tunisian study about 15 cases]

BACKGROUND

The primary type 1 hyperoxaluria (HP1) is the most frequent and severe form of the primary hyperoxaluriae. It is related to an enzymatic deficit in alanine glyoxylate aminotransferase (AGT). It is a recessive autosomic disease. Rare in Europe, it is responsible for 13% of the end stage renal failure in the Tunisian child.

AIM

The aim of this work is to evaluate the biological and molecular examinations contributing with the early diagnosis and the follow-up of the HP1 patients and to test their response to pyridoxin.

PATIENTS AND METHODS

A prospective study of 15 children who have oxaluria lower than 500 μmol/l and normal renal function is carried out. The cristalluria study, oxaluria and the glycolate-glycerate urinary ratio were carried out on all the patients. The so-called mutation maghrebean T853 (Ile244 Thr) was detected by direct sequencing of the exon 7 gene AGXT. The response to pyridoxin was tested among 13 patients.

RESULTS

The oxaluria concentration was greater or equal to 1000 μmol/l in nine cases (60%) and ranging between 600 and 1000 μmol/l in the remaining cases. The oxaluria flow was significantly high depending on the age. The glycolaturia was high among eight patients (57%). In 61,5% of the cases, the most frequent crystalline species was whewellite (C1). The "maghrebin" mutation was identified in nine patients at the heterozygous state, showing 25% allelic frequency. The response to pyridoxin was observed in the 13 tested cases.

CONCLUSION

The HP1 is frequent in our country from where the need for an early diagnosis. The use of simple biochemical tools such as the study of the cristalluria, the morphological analysis of stones and the oxaluria allow to direct the diagnosis towards a HP1, confirmed by the glycolaturia determination. The molecular biology is required in the atypical forms.

[Cystine lithiasis: retrospective study about 25 cases]

INTRODUCTION

cystinuria is a severe form of renal which is exposed the patient at multiple recurrent.

OBJECTIVE

Report and identify the clinical and biochemical characteristic of cystinuria in Tunisian region.

METHODS

It is a study of 25 cases of cystinuria, concerning at 16 adults and 9 children from 1995 to 2006. Cystinuria is recognized on the basis of spectrophotometric analysis of the stones (24/1586), by study of urinary crystals completed with brands test (5 cases) or by the two types of explorations.

RESULTS

the frequence of cystinuria is 1.5% (25/1586). 89% stones were renal and 23% were bilateral. The stones have a diameter between 15/30 mm and classified type V at morphology.

CONCLUSION

Our data will improve the management based on early diagnosis, regular follow up and respect of dietetic rules.

[Hemoglobin C disease: report of 16 Tunisian cases]

AIM

was to provide the clinical and biological patterns hemoglobine disease in Tunisia.

METHODS

This retrospective study collected to 16 cases of hemoglobin C disease : 6 homozygotic Hb C and 10 heterozygotic Hb C/beta-thalassemia.

RESULTS

The clinical profile is characterized by mild hemolytic anemia (Hb = 11.7 g/dl) associated with splenomegaly and hypersplenism. Contrary to homozygous state, the Hb C/beta-thalassemia is associated with microcytosis and pseudopolycythemia. The diagnosis is based on target cells, specific intraerythrocytic Hb C crystals in blood smear and Hb C level at 100%.

CONCLUSION

The Hb C disease must be considered as a benign hemoglobinopathy which is associated with a long survival without major complications.