Semiology of i nfectios diseases

Semiology of infectiosdiseases Prof. Dr.YaşarKüçükardalı Yeditepe University Faculty of Medicine Department of Internal Medicine

Semiology ; science of thefindingsandsymtoms of thedeseases

Subjective and Objectiveinformation

Infection • Infection: The invasion and multiplication of microorganisms such as bacteria, viruses,fungusand parasites that are not normally present within the body and the reaction of host tissues to these organisms and the toxins they produce. • An infection may cause no symptoms and be subclinical, or it may cause symptoms and be clinically apparent. • An infection may remain localized, or it may spread through the blood or lymphatic vessels to become systemic . • Microorganisms that live naturally in the body are not considered infections. For example, bacteria that normally live within the mouth and intestine are not infections. • transmissible diseases • communicable diseases

How bacteria and viruses enter the body Pathogenicbacteria must gain access into the body. The range of access routes for bacteria includes: • Cuts • Contaminated food or water • Close contact with an infected person • Contact with the faeces of an infected person • Breathing in the exhaled droplets when an infected person coughs or sneezes • Indirectly, by touching contaminated surfaces – such as taps, toilet handles, toys and nappies.

Viruses are spread from one person to another by: • Coughs • Sneezes • Vomits • Bites from infected animals or insects • Transfusion of thecontaminatedbloodproducts • Exposure to infected bodily fluids through activities such as sexual intercourse or sharing hypodermic needles. • Forgetting to wash your hands after handling pets and animals is another way for germs to be taken in by mouth.

Primary pathogens cause disease as a result of their presence or activity within the normal, healthy host, and their intrinsic virulence

Opportunistic pathogens can cause an infectious disease in a host with depressed resistance. • such as pathogenic bacteria or fungi in the gastrointestinal or the upper respiratory tract, An opportunistic disease requires impairment of host defenses, which may occur as a : • result of genetic defects (such as Chronic granulomatous disease), • exposure to antimicrobial drugs or immunosuppressive chemicals (as might occur following poisoning or cancerchemotherapy), • exposure to ionizing radiation,

fever • > 37.5 C oral, > 38.2 rectal • Endogenpirogens : IL-1, TNF, INF • Eksogenpirogens: Gr+, - , bacterialendooregzotoxins, • Daily physiologicalterationmayoccur 1 C • 20-30 % elderlypatientsmay not havefeverduringthinfectionepisode

Hyperpyrexia • Hyperpyrexia is a fever with an extreme elevation of body temperature greater than or equal to 41.5 °C (106.7 °F). Such a high temperature is considered a medical emergency • The most common cause is an intracranial hemorrhage sepsis, Kawasaki syndrome, neuroleptic malignant syndrome, drug effects, serotonin syndrome, thyroid storm. Heatstroke malignant hyperthermia • Infections commonly associated with hyperpyrexia include: rubeolaand enteroviralinfections • in hyperpyrexia the body's temperature regulation mechanism sets the body temperature above the normal temperature, then generates heat to achieve this temperature, while in hyperthermia the body temperature rises above its set point due to an outside source.

Causes of fever • İnfectiousdiseases • Solid andhematologicmalignancies • Vasculitisandcollageneousdiseases • Outoimmun • Granulamatous • Endocrinandmetabolic • Primaryneurologic • Other: FMF, allergicrx, alcoholichepatitis, hemolysis, histiositosis -X, drugfever, Kikuchidiseases, pancreatitis, Sweetsyndrome, pulmonaryemboli, hyperimmungloubulin D syndrome

Continuous fever: Temperature does not fluctuate more than 1 °C in 24 hours, e.g.lobar pneumonia, urinary tract infection, brucellosis, or typhus. Typhoid fever may show a specific fever pattern, with a slow stepwise increase and a high plateau. Remittent fever: Temperature remains above normal throughout the day and fluctuates more than 1 °C in 24 hours, e.g., infective endocarditis. Intermittent fever: The temperature elevation is present only for a certain period, later cycling back to normal, e.g.malaria, kala-azar, pyaemia, or septicemia Pel-Ebstein fever: A specific kind of fever associated with Hodgkin's lymphoma, being high for one week and low for the next week and so on

Mostcommonsymptomsrelatedtoside of theinfection

MostPhysicalfindingsrelatedtoside of theinfection

Characteristics of viralinfections • In general, viral infections are systemic. • This means they involve many different parts of the body or more than one body system at the same time; i.e. a runny nose, sinus congestion, cough, body aches etc. • They can be local at times as in viral conjunctivitis or "pink eye" and herpes. Only a few viral infections are painful, like herpes. • The pain of viral infections is often described as itchy or burning.

Reye syndrome Reye syndrome is sudden (acute) brain damage and liver function problems of unknown cause. The syndrome has occurred in children who have been given aspirin when they have chicken pox or the flu. Reye syndrome has become very uncommon since aspirin is no longer recommended for routine use in children.

Diagnosis of viraldiseases • Clinical presentation is used to detect viral disease by looking for history of severe muscle and joint pains before fever also detect skin rash lymph gland swelling • Laboratory investigations is not necessary to detect viral infections, because no increase in the white blood cells, the laboratory investigation is done to find other bacterial infections, if it is suspected. • Viruses commonly have self-limited life, so treatment is usually reduce the symptoms only andantipyretic and analgesicdrugs

Characteristics of bacterialinfection • The classic symptoms of a bacterial infectionare: localized redness, heat, swelling and pain. • One of the hallmarks of a bacterial infection is local pain, thatoccurs at the site of the infection. • Bacterial throat pain is often characterized by more pain on one side of the throat. • An ear infection is more likely to be diagnosed as bacterial if the pain occurs in only one ear. • Bacterialinfectionsproduces pus and milky-colored liquid

Fever withoutlocalisesymptoms • Tuberculosis • Endocarditis • Micoticanevrisma • Septicthrombophlebitis • Spondilitis • Osteomyelitis • Pneumonia • Intraabdominalabces • Pyelonephritis • Viral: CMV , mononucleosis, HIV, earlyhepatitis

Majorsymptomsmaycoexistwithfever • Eruption • Jointand bone pain • Lymphadenopathy • Faceandneckswelling • Headacheandneckstiffness • Neurologicaldisturbances • Coldangflulikesymptoms • Coughingandchestpain • icterus • Splenomegali • Diarea • Abdominalpain • Disuria • Sepsis • Heartdiseases

Fever andpatechia / purpura A petechiais a small (1 - 2 mm) red or purple spot on the skin, caused by a minor hemorrhage (broken capillaryblood vessels). • Bacteria, ricethsia, virus • DİC • Gram negativesepsis • Endocarditis • Meningococcemia • Tiphus, RockyMountain Fever, • Rubella, rubeola, mononucleosis, hepatitis, hemoragicfever

Semiology of i nfectios diseases