1/26/2016 Structure and Function of the Microbes Cardiovascular and Lymphatic Systems Learning Objective Invisible Invaders Identify the role of the cardiovascular Amazing Allies and lymphatic systems in spreading and eliminating infections. Chapter 23 Microbial Diseases of the Cardiovascular and Lymphatic System Structure and Function of the The human cardiovascular system and related structures Cardiovascular and Lymphatic Systems Cardiovascular system:circulates blood Lung through the body's tissues -Includes the heart and associated arteries, Capillaries in u veins,and capillaries Inferior vena cave main lower w -Delivers substances to and removes substances from the cells Intestines to intestines 2
1/26/2016 1 Invisible Invaders Amazing Allies Chapter 23 Microbial Diseases of the Cardiovascular and Lymphatic System Structure and Function of the Cardiovascular and Lymphatic Systems Learning Objective Identify the role of the cardiovascular and lymphatic systems in spreading and eliminating infections. Structure and Function of the Cardiovascular and Lymphatic Systems • Cardiovascular system: circulates blood th h th b d through the body's tissues – Includes the heart and associated arteries, veins, and capillaries – Delivers substances to and removes substances from the cells The human cardiovascular system and related structures Superior vena cava (main upper vein) Lung Aorta (main artery) Capillaries in lung Inferior vena cava (main lower vein) Liver Stomach Heart Spleen Kidneys Capillaries to intestines K y Intestines
1/26/2016 Structure and Function of the Cardiovascular and Lymphatic Systems A 16.T ·Blood:consists of -Fluid called plasma -Formed elements:cells and cell fragments suspended in plasma 四 Red blood cells-transports O2 and CO2 White blood cells-immunity Platlets-blood clotting An overview of the body's defenses 四 Chcle First line of defense Second line of defense Third line of defense Intact skin gocytes.such as 益岩 nd t 四
1/26/2016 2 Structure and Function of the Cardiovascular and Lymphatic Systems • Blood: consists of – Fluid called plasma – Formed elements: cells and cell fragments suspended in plasma • Red blood cells - transports O2 and CO2 • Whit bl d ll White blood cells - i it mmun y • Platlets – blood clotting Insert Table 16.1 If possible, break into multiple slides Insert Table 16.1 If possible, break into multiple slides An overview of the body’s defenses First line of defense • Intact skin •Mucous membranes and their secretions • Normal microbiota Second line of defense Third line of defense •Specialized lymphocytes: T cells and B cells •Antibodies • Phagocytes, such as neutrophils, eosinophils, dendritic cells, and macrophages • Inflammation •Fever •Antimicrobial substances
1/26/2016 Phases of Phagocytosis Phagocytosis Phago:from Greek,meaning eat Cyte:from Greek,meaning cell Ingestion of microbes or particles by a cell,performed by phagocytes 5)Bedy Macrophage engulfing rod-shaped bacteria Structure and Function of the Cardiovascular and Lymphatic Systems Macrophage Lymphatic system Plama eaves blood capilariesto beome interstitial fluid Bacterium -Lymphatic system provides an accessory return route for the interstitial fluid to the blood -Lymph capillaries transport interstitial fluid(now called lymph)to lymph vessels(lymphatics)and lymph Pseudopods nodes Very permeable Picks up microorganisms and infectious agents Lymph nodes 25 .Buboes:swollen lymph nodes
1/26/2016 3 Phagocytosis • Phago: from Greek, meaning eat • Cyte: from Greek, meaning cell • Ingestion of microbes or particles by a cell, performed by phagocytes Phases of Phagocytosis Macrophage Macrophage engulfing rod-shaped bacteria Pseudopods Bacterium Structure and Function of the Cardiovascular and Lymphatic Systems • Lymphatic system – Plasma leaves blood capillaries to become interstitial fluid – Lymphatic system provides an accessory return route for the interstitial fluid to the blood – Lymph capillaries transport interstitial fluid (now called lymph) to lymph vessels (lymphatics) and lymph nodes • Very permeable • Picks up microorganisms and infectious agents – Lymph nodes (a component of the immune system) contain fixed macrophages, B cells, and T cells • Buboes: swollen lymph nodes
1/26/2016 Relationship between cardiovascular and lymphatic systems Bacterial Diseases of the Cardiovascular and Lymphatic Systems atic To h Learning Objectives List the signs and symptoms of sepsis,and explain the importance of infections that develop into septic shock. Differentiate gram-negative sepsis,gram- positive sepsis,and puerperal sepsis. a)Capillary system in lung b)Lymph node Describe the epidemiologies of endocarditis and rheumatic fever. Discuss the epidemiology of tularemia. Bacterial Diseases of the Cardiovascular Bacterial Diseases of the Cardiovascular and Lymphatic Systems and Lymphatic Systems Learning Objectives Learning Objectives Discuss the epidemiology of brucellosis. Compare and contrast the causative agents, vecfors,reservoirs,symptoms,freatments Discuss the epidemiology of anthrax. and preventive measures for plague.Lyme Discuss the epidemiology of gas gangrene disease,and Rocky Mountain spotted Identify pathogens and the diseases that fever. are transmitted by animal bites and Describe the epidemiologies of epidemic scratches. typhus,endemic murine typhus,and spotted fevers
1/26/2016 4 Relationship between cardiovascular and lymphatic systems To lymphatic system Venule To heart Interstitial fluid To lymphatic system Valve to Lymphocytes and macrophages Tissue cells Lymph capillaries Blood From heart Arteriole prevent backflow From lymphatic ill t capillaries capillary system a) Capillary system in lung b) Lymph node a) From the capillaries, some blood plasma filters into the surrounding tissue where it is called interstitial fluid and enters the lymph capillaries. This fluid, now called lymph, returns to the heart through the lymphatic circulatory system (green). b) All lymph returning to the heart must pass through at least one lymph node Bacterial Diseases of the Cardiovascular and Lymphatic Systems Learning Objectives List the signs and symptoms of sepsis, and explain the importance of infections that develop into septic shock. Differentiate gram-negative sepsis, grampositive sepsis and puerperal sepsis positive sepsis, and puerperal sepsis. Describe the epidemiologies of endocarditis and rheumatic fever. Discuss the epidemiology of tularemia. Bacterial Diseases of the Cardiovascular and Lymphatic Systems Learning Objectives Discuss the epidemiology of brucellosis. Discuss the epidemiology of anthrax. Discuss the epidemiology of gas gangrene. Identify pathogens and the diseases that are transmitted by animal bites and scratches. Bacterial Diseases of the Cardiovascular and Lymphatic Systems Learning Objectives Compare and contrast the causative agents, vectors, reservoirs, symptoms, treatments, and preventive measures for plague, Lyme disease, and Rocky Mountain spotted fever. Describe the epidemiologies of epidemic typhus, endemic murine typhus, and spotted fevers
1/26/2016 Sepsis and Septic Shock Blood is normally sterile Moderate numbers of bacteria ·Septicemia canenter the bloodstream, eiethe preceofpe or thirtor especially in hospital settings due ·Sepsis to invasive procedures -Systemic inflammatory response syndrome(SIRS) Blood and lymph contain defensive -Caused by an infection that releases mediators of inflammation phagocytic cells into the bloodstreom -Site of infection is not necessorily the blood Blood is low in free iron Once in the blood,bacteria are widely diss Visible as red streaks from the site of infection ·Severe sepsis body's defenses fail -Decreased blood pressure and dysfunction of at least one orgar Septic shock -Sepsis and uncontrollable decreased blood pressure Lymphangitis.one sign of sepsis Gram-Negative Sepsis Also called endotoxin shock Endotoxins(lipopolysaccharides [LPS])cause a severe drop in blood pressure Antibiotics can worsen the condition by killing bacteria Treatment involves neutralizing the LPS components and inflammatory-causing cytokines 750,000 cases of septic shock in the US annually and 225,000 are fatal
1/26/2016 5 • Blood is normally sterile • Moderate numbers of bacteria can enter the bloodstream, especially in hospital settings due to invasive procedures • Blood and lymph contain defensive phagocytic cells • Blood is low in free iron • O nce i th bl d b t i in th e bloo d, bacteria are widely disseminated and some can reproduce in the blood if the body’s defenses fail Sepsis and Septic Shock • Septicemia – Acute illness due to the presence of pathogens or their toxins in the blood • S i eps s – Systemic inflammatory response syndrome (SIRS) – Caused by an infection that releases mediators of inflammation into the bloodstream – Site of infection is not necessarily the blood • Lymphangitis – Inflamed lymph vessels – Visible as red streaks from the site of infection • Severe sepsis – Decreased blood pressure and dysfunction of at least one organ • Septic shock – Sepsis and uncontrollable decreased blood pressure Lymphangitis, one sign of sepsis Gram-Negative Sepsis • Also called endotoxin shock • Endotoxins (lipopolysaccharides [LPS]) cause a severe drop in blood pressure • Antibiotics can worsen the condition by killing bacteria • Treatment involves neutralizin g the LPS components and inflammatory-causing cytokines • 750,000 cases of septic shock in the US annually and 225,000 are fatal
1/26/2016 Gram-Positive Sepsis Most common cause of sepsis Puerperal Sepsis Potent exotoxins that cause toxic shock syndrome ·8a+2ae2anps7l5adpeoet8k8eot Also called puerperal fever and childbirth fever components or even DNA Hospital-acquired infections -Caused by Streptococcus pyogenes -Transmitted to the mother during ·Inhabit the colon childbirth Colonize wounds and the urinary tract Resistant to many antibiotics -Group B streptococci(GBS) ·年ec6go6rt间 Streptococcus agalactioe Modern hygienic practices have made this an -Neonatal sepsis that is life-threatening uncommon complication of childbirth. Bacterial Infections of the Heart Rheumatic Fever 2g黑能onimtecTion wall o时3yer Autoimmune complication of 5.pyogenes infections Ages 4-18:often following a case of streptococcal sore throat Arthritis and fever initially Leads to inflammation of the heart valves -Immune reaction against streptococcal M protein -Re-infection renews the immune attack Acute bacterial endocarditis Subcutaneous nodules at the joints Ropid progression of the disease Sydenham's chorea -Coused by Staphylococcus aureus -10%of rheumatic fever cases develop Pericarditis -Inflammation of the arourd the Pericardium is a double-walled complications sac around the heart -Purposeless,involuntary mo ts du ing waking hours 6
1/26/2016 6 Gram-Positive Sepsis • Most common cause of sepsis • Potent exotoxins that cause toxic shock syndrome • Bacterial components that lead to toxic shock are not compl t l k ibl letely known, possibl y gram-positi ll ll itive cell wall components or even DNA • Hospital-acquired infections – Enterococcus faecium and Enterococcus faecalis • Inhabit the colon • Colonize wounds and the urinary tract • Resistant to many antibiotics – Group B streptococci (GBS) • Streptococcus agalactiae – Neonatal sepsis that is life-threatening – CDC recommends that pregnant women be tested for GBS and those with GBS be offered antibiotics Puerperal Sepsis • Also called puerperal fever and childbi th f hildbi rth fever – Caused by Streptococcus pyogenes – Transmitted to the mother during childbirth • Infects the uterus and progresses to an infection of the abdominal cavity (peritonitis) • Modern hygienic practices have made this an uncommon complication of childbirth. Bacterial Infections of the Heart • Pathogen source usually an infection elsewhere in the body • Endocarditis – Inflammation of the endocardium Heart wall consists of 3 layers • Subacute bacterial endocarditis – Impairs the function of the heart valves – Particularly in patients with heart abnormalities – Alpha-hemolytic streptococci from an oral or tonsil infection • Acute bacterial endocarditis – Rapid progression of the disease – Caused by Staphylococcus aureus • Pericarditis – Inflammation of the sac around the heart – Streptococci Pericardium is a double-walled sac around the heart Rheumatic Fever • Autoimmune complication of S. pyogenes infections • Ages 4-18; often following a case of streptococcal sore throat • Arthritis and fever initially • Leads to inflammation of the heart valves – Immune reaction against streptococcal M protein – Re-infection renews the immune attack • Subcutaneous nodules at the joints • Sydenham's chorea – 10% of rheumatic fever cases develop complications – Purposeless, involuntary movements during waking hours
1/26/2016 A nodule caused by rheumatic fever Caused by Francisella tularensis -Gram-negative rod Tularemia Zoonotic disease -Creates an ulcer at the site of entry -Mortality usually3% Nodule wjoint Bacteria reproduce in phagocytes -Enlarges the regioral lymph -Makes chemotherapy more difficult -Infective dose is small -Mortality rate>30% Tularemia cases in the United States(2001-2010) Brucellosis(Undulant Fever) 500,000 new human cases annually World's most common bacterial zoonosis Middle East and Mexico-endemic areas Brucella spp. -Aerobic gram-negative rods -Brucella abartus(elk,bison,cows) Brucella suis (swine) -Brucella melitensis (goats,sheep,camels) Perisists in the reticuloendothelial(macrophage)system: KEY evades phagocytes;becomes chronic and can affect any organ Undulant fever (malaise,night sweats,muscle aches) er county Not usually fatal 1
1/26/2016 7 A nodule caused by rheumatic fever Tularemia • Caused by Francisella tularensis – Gram-negative rod • Zoonotic disease • Transmitted from rabbits, ticks, and deer flies – Entry via several routes, wound most common – Creates an ulcer at the site of entry – Mortality usually 30% F. tularensis bacteria (blue) infecting a macrophage (yellow) Tularemia cases in the United States (2001–2010) Brucellosis (Undulant Fever) • 500,000 new human cases annually • World’s most common bacterial zoonosis • Middle East and Mexico - endemic areas • Brucella spp. – Aerobic gram-negative rods – Brucella abortus (elk, bison, cows) – Brucella suis (swine) – Brucella melitensis (goats, sheep, camels) • Transm m fmf m w itted via milk from infected animals or contact with infected animals • Perisists in the reticuloendothelial (macrophage) system; evades phagocytes; becomes chronic and can affect any organ • Undulant fever (malaise, night sweats, muscle aches) – Not usually fatal
1/26/2016 Caused by Bacillus anthracis The Anthrax -Gram-positive,endospore-forming Anthrax Cycle aerobic rod Found in soil:spores survive up to 60 years Primarily affects grazing animals: fatal sepsis Spores introduced into the body are taken up by macrophages and germinate -Bacteria enter the bloodstream and release toxins Treated with ciprofloxacin or doxycycline Vaccination of livestock Anthrax Three Forms of Anthrax Cutaneous anthrax Bacteria produces virulence factors -Endospores enter through a minor cut -Protective antigen:binds the toxins to -90%of human form of anthrax target cells,permitting their entry -20%mortality if enters the bloodstream without freatment -Edema toxin:causes local swelling and interferes with phagocytosis Gastrointestinal anthrax(rare) Ingestion of undercooked.contaminated food -Lethal toxin:targets and kills -50%mortality rate macrophages Inhalational((pulmonary）anthrax Amino acid capsule that avoids an -Inhalation of endospores immune response -Bacteria enter the bloodstream:progresses into sept tic shock Near 100%mortality rate Bioterrorism
1/26/2016 8 Anthrax • Caused by Bacillus anthracis – Gram-positive, endospore-forming aerobic rod • Found in soil; spores survive up to 60 years • Primarily affects grazing animals; fatal sepsis • Spores introduced into the body are taken up by macrophages and germinate – B t i t th bl d t d Bacteria enter the bloodstream and release toxins • Treated with ciprofloxacin or doxycycline • Vaccination of livestock Bacillus anthracis spores in a murine macrophage Anthrax • Bacteria produces virulence factors – Protective antigen: binds the toxins to t t ll itti th i t target cells, permitting their entry – Edema toxin: causes local swelling and interferes with phagocytosis – Lethal toxin: targets and kills macrophages – Amino acid capsule that avoids an immune response Three Forms of Anthrax • Cutaneous anthrax – Endospores enter through a minor cut – 90% of human form of anthrax – 20% mortality if enters the bloodstream without treatment • Gastrointestinal anthrax (rare) – Ingestion of undercooked, contaminated food – 50% mortality rate • Inhalational (pulmonary) anthrax – Inhalation of endospores – Bacteria enter the bloodstream; progresses into septic shock – Near 100% mortality rate – Bioterrorism
1/26/2016 Applications of Microbiology:Protection against Bioterrorism 1346:plague-ridden bodies used by the Tartar army against Kaffa (Ukraine) 1937-1945:plague-carrying flea bombs used in the Sino-Japanese War 1979:explosion of B.anthracis weapons plant in the Soviet Union 1984:Salmone/la enterica used against the people of The Dalles,Oregon 1996:Shigella dysenteriae used to contaminate food 2001:B.anthracis distributed in the United States Potential Biological Weapons Gangrene Bacteria Viruses Ischemia:loss of blood supply to tissue Necrosis:death of tissue Gangrene:death of soft tissue Chianycloolia puracl Hemohaoicever vruses (boa Marbug.Lassa) ·Gas gangrene Coctndtumbotu4numon Monkeypox -Caused by Clostridium perfringens,a gram-positive, Coxloto bumnen Nipah irus endospore-forming anaerobic rod ianhdtular Grows in necrotic tissue:dead tissue provides ikn0powa nutrients:ferments carbohydrates with gas g物p Produces toxins that move along muscle bundles that kill the tissues v cholrae -Treatment includes the surgical removal of necrotic Yep tissue and/or use of a hyperbaric chamber
1/26/2016 9 Applications of Microbiology: Protection against Bioterrorism • 1346: plague-ridden bodies used by the Tartar army against Kaffa (Ukraine) • 1937–1945: plague-carrying flea bombs used in the Sino-Japanese War • 1979: explosion of B. anthracis weapons plant in the Soviet Union • 1984 : Salmonella enterica used against the people of The Dalles, Oregon • 1996: Shigella dysenteriae used to contaminate food • 2001: B. anthracis distributed in the United States Potential Biological Weapons Gangrene • Ischemia: loss of blood supply to tissue • Necrosis: death of tissue • Gangrene: death of soft tissue • Gas gangrene – Caused by Clostridium perfringens, a gram-positive, endospore-forming anaerobic rod • Grows in necrotic tissue; dead tissue provides nut i t f t b h d t ith trients; ferments carbohydrates with gas • Produces toxins that move along muscle bundles that kill the tissues – Treatment includes the surgical removal of necrotic tissue and/or use of a hyperbaric chamber
1/26/2016 Systemic Diseases Caused by Bites The toes of a patient and Scratches with gangrene .1%of ER visits:4.4 million annually in US Dogs make up 80%of reported bites: cats about 10% -Cat bites have higher infection rates Pasteurella multocida oxygen rich -Gram-negative rod:causes sepsis Staphylococcus,Streptococcus, Corynebacterium Cat-Scratch Disease Caused by Bartonella henselae -Aerobic,gram-negative cells ced in the -Multiplies in the digestive system of cat fleas Cat claws contaminated with flea feces scratch human Forms a papule at site of infection and swollen lymph nodes .Self-limiting 回a 22,000 cases annually in the US Cat Scratch Disease 10
1/26/2016 10 The toes of a patient with gangrene H b i Ch b Hyperbaric Chamber: pressurized oxygen rich atmosphere Systemic Diseases Caused by Bites and Scratches • 1% of ER visits; 4.4 million annually in US • Dogs make up 80% of reported bites; cats about 10% – Cat bites have higher infection rates • Pasteurella multocida – Gram-negative rod; causes sepsis • Staphylococcus, Streptococcus, Corynebacterium Cat-Scratch Disease • Caused by Bartonella henselae – Aerobic, gram-negative – Inhabits cat red blood cells; carried in the blood of 50% of cats – Multiplies in the digestive system of cat fleas • Cat claws contaminated with flea feces scratch human • Forms a papule at site of infection and swollen lymph nodes • Self-limiting • 22,000 cases annually in the US Electron micrograph showing the location of Bartonella henselae within a red blood cell Pore Red blood cell B. henselae Cat Scratch Disease