Dentistry

Immune thrombocytopenic purpura (ITP) •           Also called idiopathic thrombocytopenic purpura •           Autoimmune disorder with production of anti-platelet antibody causing destruction of platelet –         Primary or idiopathic( absence of any known risk factors ) –         Secondary •           Primary –         Acute –         Chronic- more common •           Secondary –         Systemic lupus erythematosus    –         AIDS –         After viral infection –         drug therapy Chronic ITP •           Adult women younger than age 40 years •           F:M= 3:1 •           Insidious onset •           Bleeding into skin and mucosal surfaces •           Petechiae, ecchymoses •           H/O nosebleeds, bleeding from gums, hemorrhage into soft tissues from minor trauma •             May present with melena, hematuria or excessive menstrual flow •             Subarachnoid hemorrhage and intracerebral hemorrhage: Serious consequences

Glucose-6-phosphate dehydrogenase deficiency The red cell   vulnerable to injury by endogenous and exogenous oxidants are normally inactivated by reduced glutathione (GSH). Oxidants such as hydrogen peroxide are stopped by GSH, which is converted to oxidized glutathione in the process   •           X- linked recessive, males •           Hemolysis after exposure to oxidant stress •           Oxidant drugs: antimalarial, sulfonamide, nitrofurantoins •           Infections: viral hepatitis, pneumonia, typhoid fever •           Foods: Fava beans •           Causes episodic intravascular and extravascular hemolysis, which involve the following sequence: –         Exposure of G6PD deficient red cells to oxidants –         Regeneration of GSH is impaired in G6PD-deficient cells, hydrogen peroxide attack globin chains, which have sulfhydryl groups that are susceptible to oxidation –           Oxidized Hb denatures and precipitates, forming intracellular inclusions call

White Cell Disorders •        Leukocytosis •        Leukopenia •        Leukemoid reaction •        Leukemia •        Myeloproliferative disorders Leukocytosis is a raised white blood cell count (the leukocyte count) above the normal range •        white blood cell count greater than 11,000/ mm3 (11.0 x 10 9 /L) •        Common in a variety of reactive inflammatory states caused by microbial and nonmicrobial stimuli •          Nonspecific and can be classified on the basis of the particular white cell series affected Classification •        Neutrophilia •        Eosinophilia •        Basophilia •        Monocytosis •        Lymphocytosis Neutrophilia •        Pathological –       Acute bacterial infection (pyogenic organisms) –       Inflammation §   Myocardial infarction §   Burns –       Corticosteroid therapy –       Leukemia •        Physiological –       Pregnancy –       Severe exercise, stress Eosinophilia •        P

Bleeding disorders •           characterized clinically by abnormal bleeding –           Spontaneous –           Trauma or surgery –         Systemic conditions that activate or damage endothelial cells A normal hemostatic response involves blood vessel wall, platelets and clotting cascade •           Excessive bleeding can result from Increased fragility of vessels Platelet deficiency or dysfunction Derangement of coagulation Combinations of these Bleeding disorders   •           Vessels wall abnormalities •           Reduced platelet number •           Defective platelet function   •           Abnormalities in clotting factors •           Disseminated intravascular coagulation

Lymphadenopathy (LAD) refers to enlargement of nodes, with or without tenderness Always note size, number, tenderness, consistency and mobility of LAD Localized LAD Often from a local source, Generalized LAD usually refers to LAD in at least 2 different lymph node regions                Infection, neoplasia, drugs Generalised lymphadenopathy: A few causes Viral EBV, CMV, HIV Measles, rubella Brucellosis

BLOOD Connective Tissue Cells (45%) suspended in fluids (Plasma- 55%) Delivers necessary substances such as nutrients and oxygen to body’s cells and transport waste products away from those cells •       Plasma •       Red Blood cells •       Platelets •       White Blood Cells •       Metabolism in Reticulocytes Reticulocytes—immature red blood cells –     Develops and matures in red bone marrow –     Anucleated –     Enters circulation, loses intracellular organelles (eg, mitochondria, ER etc) and ribosome within 24 hrs    Becomes young RBC & loses ability to

Metronidazole: A prototype nitroimidazole.  Tissue amoebicide Broad spectrum cidal activity Mechanism of action:                  Diffusion into cell of amoeba     Nitro group reduced into highly reactive nitro radical by redox      potential of anaerobes                                                                             Causes cytotoxicity by damaging DNA Nitro radical acts as electron sink which competes with the biological electron acceptor of anaerobic organism for the electrons generated by pyruvate oxidation          Disruption of energy metabolism of anaerobes —   Uses and dosage regimens: 1. Amoebiasis: Ø   mild intestinal disease: 400mg TDS for 5-7 days Ø Invasive dysentery and liver abscess: 800mg TDS for 7-10 days 2. Giardiasis: Ø 400mg TDS for 7 days 3. Trichomonas vaginitis: Ø 400mg TDS for 7 days 4. Anaerobic bacterial infection: Ø For serious cases, iv 15mg/kg infused over 1 hour followed by 7.5mg/kg every 6 hours t