الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 174 |  |  |
| | | from | 174 | | |
Abstract
Platelets are the smallest and yet extremely reactive blood morphotic component. They are involved in the processes of fibrosis and maintenance of hemostasis. (50) Also, platelets secrete microbicidal proteins and antibacterial peptides, in addition, they mediate leukocyte movement from the bloodstream through the vessel wall to tissues. (54-56) Platelet indices are biomarkers of platelet activation as they allow extensive clinical investigations focusing on the diagnostic and prognostic values in a variety of settings without bringing extra costs. Among these platelet indices, plateletcrit (PCT), mean platelet volume (MPV), and platelet distribution width (PDW) are a group of platelet parameters determined together in automatic CBC profiles; they are related to platelets’ morphology and proliferation. (60-61) During activation, platelets’ shapes change from biconcave discs to spherical, and a pronounced pseudopod formation occurs that leads to MPV increase during platelet activation. Plateletcrit is the volume occupied by platelets in the blood as a percentage and calculated according to the formula PCT = platelet count × MPV / 10,000.(74-77) Simultaneous measurement of all of the platelet indices will provide us a valid instrument for measuring disease severity and an insight into the potential etiology that resulted in platelets’ indices changes. Numerous research groups have found a relationship between the changes in platelet indices and the activation of the coagulation system, severe infection, trauma, systemic inflammatory reaction syndrome, and thrombotic diseases. (81) This study aimed to investigate the relationship between platelet indices and illness severity and their performance in predicting mortality in critically ill children. (93) This was a prospective observational study that was done at Tanta Pediatric Intensive Care Units from October 2021 to September 2022 on 200 critically ill infants and children who were the patient group (group 1) and on 200 healthy infants and children with the comparable age and sex (group 2). The study was approved by the Ethics committee of faculty of medicine, Tanta university (NO. 34764/6/21). Inclusion criteria: All infants and children from 2 months till the age of 17 Years. Exclusion criteria: 1. Age lesser than 2months or more than 17 years. 2. Patient who died or transferred to other hospitals within 24 hours from admission . 3. Patients with primary platelet disease that affect the platelet indices. 4. Patients whose guardians refused to share in the study. All patients were subjected to the following, *Informed consent: An informed consent was taken from all participants guardians. *History taking: -Personal history: age, sex ,residence.. -Present history: complains and their analysis. -Past medical history: chronic illness, hospital admission, blood or blood product transfusion. -Past surgical history: any surgical operation / procedure and possible complications. -Family history: consanguinity, similar condition, chronic diseases and familial diseases. -Obstetric history: prenatal, natal and post-natal. -Nutritional history. -Developmental history: motor, verbal, social and dentation . *Clinical examination: All participants were subjected to thorough clinical examination in the form of vital signs, general and systemic examination . *Pediatric scoring systems: (for patient group only) SOFA score and PRISM III score. *Routine laboratory investigations including: CBC, LFT, RFT, Electrolytes, RBS, CRP, Bleeding profile, Blood & other body fluids culture when indicated. *Specific research laboratory investigations (For both patient and control group) : Platelet distribution width “PDW”, Mean platelet volume (MPV), plateletcrit (PCT). *Radiological investigations including: chest x-ray, abdominal US, CT, MRI when indicated. * Invasive Procedures: Bone marrow aspirate/biopsy Pleural aspiration, pericardiocentesis and analysis of the aspirated fluid when indicated. Results: 256 patients were admitted at Tanta Pediatric Care Units but 56 patients were excluded as, 23 cases had primary platelet disease that affects platelet indices. 18 cases died within 24 hours from admission. 12 cases their gaurdians refuse to participate in the study. 3 cases transferred to other hospitals within 24 hours of admission. On the Other hand similar data was collected from 200 healthy infants and children who were relatives of our patients . There was no significant difference as regarding to age and sex between both patient and control group. As regarding to Hemoglobin ( Hb) , Mean Corpuscular Volume (MCV), Mean Corpuscular Hemoglobin (MCH ) and Lymphocytic count their results were significantly higher in Control group .While Total Leukocytic Count ( TLC) and Neutrophilic count were significantly higher in patient group . Platelet count and PCT (Plateletcrit) were significantly lower in patient group. While MPV ( Mean Platelet Volume )and PDW (Platelet Distribution Width) were significantly higher in patient group . PDW (Platelet Distribution Width) and MPV (Mean Platelet volume) are directly related to each others and both are inversely related to PCT (Plateletcrit). Among 200 critically ill patient 33% of them died and 67% survived and were discharged. MPV ( Mean Platelet Volume ) and PDW ( Platelet Dstribution Width) were significantly higher in non survivors .While PCT ( Plateletcrit ) was significantly lower in non survivors. PCT ( Platelcrit ) was inversely related to PRISM and SOFA scores while MPV (Mean Platelet Volume) and PDW (Platelet Distribution Width ) were directly related to PRISM and SOFA scores . Platelet count significantly decreased with decreased PCT (plateletcrit) and Increased MPV (Mean Platelet Volume) and PDW (Platelet Distribution Width ) , Also RBS , Lymphocytic count ,Serum albumin showed similar results .Whereas PH was significantly increased with increased PCT (Plateletcrit) with and showed no significant change with MPV ( Mean Platelet Volume ) and PDW ( Platelet Distribution Width) ,While HCO3 showed significant increase with increased PCT ( Plateletcrit ) and significant decrease with increased MPV (Mean Platelet Volume ) . Total Leukocytic Count (TLC) significantly increased with MPV (Mean Platelet Volume) and PDW (Platelet Distribution Width) , while it is significantly decreased with PLC (Plateletcrit) , Also Neutrophil count ,CRP , ALT, AST and Urea showed similar results . PDW ( Platelet Distribution Width ) was the most sensitive parameter to discriminate between patient and control group with sensitivity 96% and cut off value>17 , while PCT ( Plateletcrit ) was the most specific parameter with 99% specificity and cut off value ≤0.21 . PCT (Plateletcrit) was the most sensitive parameter to predict mortality in patient group with sensitivity 86.57% and cut off value>0.16 . While MPV (Mean Platelet Volume) and PDW (Platelet Distribution Width) were the most specific with specific parameters to predict mortality in patient group with specificity 87.88% with cut off value ≤17 and ≤25.8 respectivelly.