ABSTRACT
Acute Leukemias [AL] are the most common malignancy In childhood [33%] with acute Iymphoblestlc leukemia [ALL] constituting 75% of cases. Thirty years have elapsed since the first description of leukemic inhItration of central nervous system [CNS], however It still remains 8 problem In ALL. Fibronectin is a high molecular weight glycoprotein that Is detectable in the normal CSF at low concentration. Thymidine kinase is a cytoplasmIc scavenger enzyme present In dividing cells which converts thymidine Into thymidine monophosphate. It is usually undetectable In CSF of most normal individuals. We studied 20 newly diagnosed children with ALL [11 males and 9 females], none of them showed any evidence of CNS leukemia at diagnosis. Determination of thymidine kinase and Fibronectin concentrations In CSF of the studied cases was done at diagnosis. The studied children were followed up for an average of 2 years [range 1.6 - 25 years] after the start of Induction treatment. All of them echleved complete remission. During the treatment period 5 patients showed an evidence of CNS Involvement. The duration tiII CNS relapse ranged between 10 months and 12 months. Our results showed significantly higher Ievels of CSF thymidine kinase and fibronectin In patients who showed CNS disease men In those who had either remained on maintenance chemotherapy, completed the treatment or relapsed In other sites [R0. 0001 and P<.05 respectively]. Meningeal leukemia occurred In almost 70% of our patients [5 out of 7 patients] who showed CSF thymidine kinase values above the upper Limit of the normal range [1.4 U/microI.] recorded at diagnosis, while comparable levels were found In only 13% [2 out of 15 patients] without CNS relapse. Determination of levels of these markers [thymidine kinase and fibronectin] may be compiled with the more recent techniques that can Identify leukemic cells In CSF [as sensitive polymerase chain reaction assays] may help In prediction of patients with high risk of CNS relapse. These methods could be potentially useful in identifying sub-groups of ALL patients with no Initial CNS disease who require a more Intensive presymptanatic prophylactic CNS therapy
ABSTRACT
Saudi Arabia used to by hyperendemic for HBV infection. Most of infection occurs in early life. HBV vaccine was, therefore, introduced in 1989 as the seventh primary immunogen of the EPI Program. This study is conducted to evaluate the efficacy of this program in Riyadh and Hail Regions. Method and Patients: A cohort follow-up study of children from Riyadh and Hail, who had been vaccinated in 1989, evaluated in 1991 and tested for HBV markers six years later. The files of 303 children from Riyadh and Hail, who were investigated in 1991retrieved and only 119, were available for testing. Fifty% of the children have still a protective anti- HBs tittr. One vaccinated child was found to be positive for HBs Ag. According to this study, the efficacy rate against HBs Ag carriage is 88%. This study demonstrates the tremendous effect of HB vaccine on the HBV infection of Saudi children in these two regions