Comprehensive Microbial List Flashcards

Question

Tularemia (Francisella tularensis)

Answer 1

- reservoir in rabbits and rodents infection from contact; vector is ticks, deerflies, and mosquitoes. - metastatic infection--survives within macrophages (granulomatous reaction) - Acute febrile disease, lymphatic distribution. - Distribute to major organs via lymph =\> enlarge, hard nodes =\> granulomas (necrotizing, described as ‘palisading’) - Ulceroglandular: pustular lesions (necrosis) with lymphadenopathy and acute febrile illness--significant mortality if untreated - Occuloglandular = Spread from eye to parotid gland

Answer 2

- transmitted via mosquito bites - inflammatory parasitic infection of lymphatic vessels: lymphangitis and sometimes lymphatic obstruction - edema with thickening of the skin and underlying tissue-elephantiasis - Often unilateral, involving scrotum/leg - Occult filariasis (anti-filarial antibodies) produces tropical pulmonary eosinophilia--can lead to fatal pneumonia.

Answer 3

- infectious mononucleosis: fever, malaise, pharyngitis, splenomegaly - lymphadenopathy--spleen and lymph nodes (cervical) - atypical lymphocytes - heterophilic antibody--distinguishing lab test

Answer 4

- Epidemiology: First emerged in Africa, Zaire and Sudan in 1976. Outbreaks caused by Ebola Zaire and Sudan strains primarily. Outbreaks occured in Gabon, Republic of Congo, and Uganda. Fatality rate 53 to 89%. January 2008--Ebola Bundibugyo strain emerged in Uganda. Fruit bats are reservoir for virus. Virus can be spread by bodily secretions, blood, and used needles. - Pathology: widespread destructive tissue lesions--most damage of all viral hemorrhagic fever agents. Replicates in endothelial cells, mononuclear phagocytes, and hepatocytes. Necrosis is most severe in liver, kidneys, gonads, spleen, and lymph nodes. Hepatocellular necrosis + Kupffer cell hyperplasia, Councilman bodies, and microsteatosis seen in liver biopsies. Lungs hemorrhagic and petechial hemorrhages seen in skin, mucous membranes, and internal organs. Injury to microvasculature--increase vascular permeability leads to shock. - Clinical Features: incubation time is 2 to 21 days. Initial symptoms headache, weakness, and fever, followed by diarrhea, nausea, and vomiting. Severe disease characterized by overt hemorrhage including bleeding from injection sites, petechia, GI bleeding, and gingival hemorrhage.

Answer 5

- aerobic, curved, gram(-) rod - spread from ingesting contaminated food/water; shellfish are natural reservoir--sporadic outbreaks - epidemics in areas where human feces pollute water supply -cholera exotoxin: binds GM1 ganglioside in enterocyte cell membrane to enter cell and activated adenylyl cylase- increase cAMP and increase Na+/H20 secretion into intestinal lumen. -severe watery diarrhea with flecked mucus (rice water stools)--leads to fluid and electrolyte loss that leads to shock - 50% mortality rate in untreated patients (lacking electrolyte and oral rehydration therapy +antibiotis) - vaccine available (50% effectiveness)

Answer 6

- Gram(-), highly motile. -granulomatous--taken up by macrophages - Pyogenic STD with 3 characteristic stages - Primary: Chancre (firm, painless) with luetic vasculitis, occasionally multiple lesions in immunecompromised. - Secondary: (involves systemic spread) Maculopapular rash on palms and soles of the feet, follicular and numular syphilids, condylomata lata (white plaques on perineum region), obliterative endarteritis. - Latent stage: Asymptomatic - Tertiary (3-15 yrs after infection): Gumma: soft, tumor-like balls of inflammation which may vary considerably in size. NeuroSyphilis - meningitis, seizure, dementia + tabes doralis (peripheral nerve demyelination) Cardiovascular syphilis- aortitis =\> aneurism. - Congenital syphilis can cause snuffles, saddle nose, saber shins, and Hutchinson teeth in newborn

Answer 7

- Found in tropics, skin-to-skin transmission - Pyogenic: neutrophilic Raspberrry-like papilloma lesion. - Diffuse skin lesions, ones on the sole of feet can cause “Crab Yaw” walking - After a latent period, re-emerges as face and upper airway lesions

Answer 8

- spread by eating contaminated vegetation (watercress) with cysts from sheep - cysts liberate metacecariae that pass into peritoneal cavity--live in intrahepatic and extrahepatic bile ducts - hepatic abscesses and granulomas - induce hyperplasia of bile duct epithelium, portal and periductal fibrosis, and biliary obstruction - Symptoms: eosinophilia, vomiting, acute gastric pain - Fatal if untreated - diagnosis: recovering eggs from stool or biliary tract

Answer 9

- endemic in sheep, goats, cattle, and sheep dogs - humans contaminated by dogs: ingest tapeworm eggs spread by dog in human living spaces - cestode has suckers and hooklets facilitating attachment - larva penetrate gut wall, enter bloodstream, disseminate into deep organs - form large (hydatid) cysts containing brood capsules and scolices - cysts can compress intrahepatic bile ducts--obstructive jaundice - Major complication: cyst rupture and seeing of adjacent tissues--proliferating cyst number and causing pain and fatal allergic reactions (anaphalactic shock)

Answer 10

- Spread from Birds in tropics. - Self-limited pneumonia,splenomegaly, rose-colored ‘Horders Spots

Answer 11

- extracellular enteric infection - diarrheal infection - self-limiting, unless immunocompromised - AIDS patients, etc, develop chronic infection with persistent chronic diarrhea that can lead to death

Answer 12

- Epidemiology: Belongs to same family as influenza. Spreads rapidly from child to child in aerosols and secretions--daycare centers, hospitals and other areas with confined children. - Pathology: Viral surface proteins interact with receptors on host respiratory epithelium-viral binding and fusion. Causes necrosis and sloughing off of bronchial, bronchiolar, and alveolar epithelium. Multinucleated syncytial cells seen. - Clinical Features: Young children with RSV bronchiolitis or pneumonitis have wheezing, cough, and respiratory distress. Illness self-limited (1-2 weeks duration). older adults produces much more mild illness. 20-40% mortality among hospitalized children with congenital heart disease.

Answer 13

- respiration or cutaneous inoculation - gram(+) aerobic filamentous - May affect lungs, brain, skin or systemic dissemination - Disease of immunocompromised. - Pyogenic: Pulmonary abcesses w/ central necrosis. - Fatal if untreated, long term antibiotics.

Answer 14

- ingested eggs in contaminated food, soil, drink - Live in the Cecum or upper colon--children especially susceptible - Invasion causes small erosions, focal active inflammation, loss of small amounts of blood - Usually asymptomatic - Heavy infestations causes cramping, abdominal pain, bloody diarrhea, weight loss and anemia

Answer 15

- Epidemiology: spreads person to person by respiratory route. Infection common and occurs in outbreaks, mostly among children. - Pathology: gains entry to erythroid precursor cells via P erythrocyte antigen and produces certain cytopathic effects: enlarged nuclei with peripheral chromatin displacement and eosinophilic material nuclear inclusion bodies. - Clinical Features: Mild exanthematous illness (rash) known as erythema infectiosum, accompanied by interruption of erythropoiesis (mostly asymptomatic). Potentially fatal anemia caused in hosts with chronic hemolytic anemia--transient aplastic crisis. Fetal infection leads to severe anemia, hydrops fetalis, and death in utero (10% of maternal infections).

Answer 16

- Gram-negative rod-shaped coccobacillus. It is a facultative anaerobe - survive/proliferate inside macrophages (granulomatous + necrotizing) - Produces plasminogen activator: hemorrhaging - Bubonic plague: spread by fleas on rats-septic shock and bulbous enlargements of lymph nodes - Septicemic plague: direct blood contamination (death quick-48 hours) - Pneumonic plague: inhalation of airborne particles, endotoxic shock in 1-2 days after infection period which follows 2-5 day incubation -tetracyclin with streptomycin

Answer 17

- obligate anaerobe, spore forming, gram(+) - bacterial benign, diarrheal food poisoning, necrotizing enteritis (enterotoxins-ulcerating ß-toxin), and gas gangrene - GAS GANGRENE: myotoxin--alpha toxin (alpha lecithinase--phospholipase) that destroys cell membranes leading to severe hemolysis and muscle necrosis--SEVERE

Answer 18

- infection of connective and subcutaneous tissues - transmitted by drinking water contaminated with intermediate host, crustacean of genus Cyclops - year incubation: symptoms: systemic allergic reaction, blisters that burst upon contact with water with female worm partially emerging - dead worms provoke intense inflammatory response

Answer 19

- Gram(+) bacteria - normal bacterial flora (skin, mucosal surfaces) - not as serious as S. aureus infections - low grade fever - spread from contaminated medical and prosthetic devices. -nosocomial variants multidrug resistant. (use non-beta lactam antibiotics)

Answer 20

- Epidemiology: ancient disease. named after latin "varius" meaning "pimple/spot". Common in Europe. Arrived in the new world by explorers and decimated native populations. Edward Jenner (1796) performed first vaccination by innoculating child with lymph from hand of milkmaid infected with cowpox. WHO began eradication campaign in 1967 leading to eradication in 1978 (Somalia last endemic cases). CDC and Russia still have virus stockpiled. - Etiology: Spread between infected and susceptible hosts via droplets or aerosol of infected saliva. Virus highly stable and remains infective for long periods outside human host. Variola major (Asia and parts of Africa--prototypical) and Variola minor (Africa, South America, and Europe--minor systemic toxicity and lesions). - Pathology: Skin vesicles of variola show reticular degeneration and areas of ballooning degeneration. Guarnieri bodies (eosinophilic, intracytoplasmic inclusion bodies) are seen, but not specific to smallpox (most poxviral infections). Vesicles also occur in palate, pharynx, trachea, and esophagus. Severe cases produce gastric and intestinal involvement, hepatitis, and interstitial nephritis. - Clinical Features: Incubatin period: 12 days (7-17 days). Spreads to regional lymph nodes to produce viremia. Abrupt malaise, fever, vomiting, and headache manifest. Characteristic rash (face and forearms) follows in 2-3 days. After eruptions on lower extremities, rash spreads central during next week to trunk. Lesions: macules--\>papules--\>pustular vesicles--\>scabs--\>scars. Fatality rate is 30% in unvaccinated.

Answer 21

- prototypical prion disease - neurodegenerative - transmitted via ingestion (cannibalism of flesh)

Answer 22

- A disfiguring, smelly facial necrosis that destroys both soft tissue and bones of mouth and face - Often targets malnourished kids in and immune compromised in the tropics - Common bacteria: T. vincentii, B. fusiformis (fusospirochetal), Bacteroides, Corynebacterium - Underlying bone may be revealed. - Usually need antibiotics and reconstructive surgery

Answer 23

- aka "Beaver Fever" and "Backpacker's Bug" - usually self-limited, normally commensual protozoa - Small Intestine, watery diarrhea. - Symptoms of GI infection + bloating, excessive gas, and burping (often sulfurous) - Malabsorption, structural and chemical changes to brush border. - Watery diarrhea - IgA deficiency?

Answer 24

- Inhaled, common in AIDS patients (probably latent endogenous infection), often fatal. - Trophozoites (yeast-like) reproduce in alveolar type 1 cells and form cysts and rupture - alveoli fill with frothy eosinophillic material; diffuse lung inflitrate. - Best seen with methenamine silver stains

Answer 25

- Histoplasma capsulatum. - Primarily effects lung, typically SELF\_LIMITED in HEALTHY. - Intracellular, macrophages = \> granulomatous, may resemble TB. =\> caseous necrosis + calcifications. - Can dissemminate bone, spleen, liver, adrenal glands, mucocutaneous membranes--AIDS, immunocompromised--fatal,

Answer 26

- chicken pox, skin vesicular eruptions - latent in dorsal ganglion--shingles in older patients (herpes zoster) - pain in single dermatome in shingles--localized painful vesicular eruption. - neutrophil filled vesicles. - fever, malaise, rash

Answer 27

- “Valley fever” “Desert Fever” - Coccidioides immitis or Coccidioides posadasii - Endemic in certain parts of Arizona, California, Nevada, New Mexico, Texas, Utah. - Flu-like, maculopapular rash, - Begins with pulm infection, then disseminates, can cause meningitis in immunocompromised. - Necrotizing, caseous granulomas, non calcifying.

Answer 28

- Rural areas of Mexico, Central America, and South America; - Flagellate protozoan, insect born zoonosis (kissing bug). - Bite =\> Invasion of macrophages / nodular ‘chagoma’ - lesion =\> dissemination - Acute illness may kill via myocarditis / encephalitis - Chronic illness involes GI dysfunction and autonomic nerve degeneration and cardiac failure--years to decades

Answer 29

- microaerophilic, curved, gram(-) rod (similar to vibrios) self-limited - spread through contaminated food/water + fecal-oral route - most common cause of bacterial diarrhea in developed world--2 million annual cases in US -affects farm animals--huge economic losses - causes superficial enterocolitis--terminal ileum and colon with focal necrosis of interstitial epithelium and acute inflammation -severe cases: ulcers and patchy inflammatory exudates (necrotic cells, fibrin, neutrophils) - watery stools, gross blood containing stools - associated with Guillain-Barre syndrome (autoimmune peripheral neuropathy)

Answer 30

- Taenia Solium = Brain Cysts - Ingestion of Larvae (Meat) =\> Gut Tapeworm - Pernicious anemia - Mostly asymptomatic - Humans shed eggs in fecal matter. - Ingestion of Eggs (Fecal) =\> Disseminated Cysts to muscle and brain - Eggs create a massive inflammatory response. “Swiss cheese brain”

Answer 31

- Mosquito-born, hemolytic, febrile illness. - obligate intracellular parasite-replicate, kill human cells - Equitorial regions (tropics) - P. falciparum tends to be worst. - Human reservoire; gametocytes are in human blood and taken up by mosquito - Reproduce sexually in mosquito = \> sporozoites - Trasmitting to human via bite; go to the liver and form merozoite, perform asexual division. - Merozoites can invade/multiply within/destroy RBCs. =\> hemosiderin-laiden Macrophages seen. - Hepatosplenomegaly - clumped, infected erythrocytes block blood vessels--hemorrhages, obstruction--acute renal failure with renal blood vessels, intravsascular hemolysis leads to hemoglobinuric nephrosis (blackwater fever)

Answer 32

- Rare, granulomatous disease. - Zoonotic; associated with horses. - Burkholderia mallei aka pseudomonas mallei - Transmission via cuts in the skin, via musoca, or inspiration. - Nodular lesions in the lungs and ulceration of the mucous membranes in the upper respiratory tract - Acute bacteremia =\> Almost always fatal. Generally a 50% mortality rate and very small minimum infectious dose.

Answer 33

- Orientia tsutsugamushi, a Gram-negative α-proteobacterium of Rickettsia family. - Transmitted by Chigger (mites) bite, leaving a black eschar that helps with diagnosis. - Endemic to parts of Russia, Korea and Japan. - Can be fatal without treatment. - Similar effects to those above.--obligate intracellular pathogen--infects endothelial cells

Answer 34

- Tick-born, malaria-like disease. - Typically non fatal (self-limited) in healthy; but immuncompromised/splenectomy =\> complications - Reproduce in red blood cells (hemolytic anemia), where they can be seen as cross-shaped inclusions (fourmerozoites asexually budding - Seen in Europe and North America

Answer 35

- gram(-) rod, facultatively anaerobic - SELF-LIMITED -spread by fecal-oral route, contaminated foodstuff - proliferate and invade enterocytes in ileum and colon-acute inflamation and some superficial ulceration - diarrhea (self-limited), nausea, vomiting, abdominal cramping, fever--food poisoning: takes 12-48 hours to manifest (no exotoxin production like S. aureus) - antibiotics rarely improve clinical course - major cause of childhood mortality in 3rd world countries (lack of oral rehydration therapy)

Answer 36

- Acute, self-limiting. - P2P droplet spread. - fever, sore throat, cough

Answer 37

- ingestion of fecal contaminated food (from dogs/cats) - hypereosinophilia, pneumonitis, hypergammaglobulinemia - cheif symptom: loss of vision in one eye. - usually Self-limited

Answer 38

- Transmitted by fly bite. - Onchocerca volvulus is the nematode, which carries a bacterial endosymbiont: Wolbachia pipientis, which causes a severe immune response that can cause blindness. - inlammatory response causes damage to cornea, choroids, retina

Answer 39

- obligate intracellular pathogen - mostly asymptomatic, problem for immunocompromised and fetus-necrotizing disease. - Undercooked pig meats, cat litter, cats shed oocysts in their feces. - Convert to tachyzoites inside intermeidate-host and replicate inside specialized vacuoles - Immune response causes conversion to bradyzoites, which are associated with cyst formation, especially in CNS and muscle. - Associated with developmental defects in fetus and neuropsychiatric disorders. - Encephalitis produced in immunocompromised hosts - Lymphadenopathy in immunocompetent hosts

Answer 40

- small, encapsulated, nonmotile, gram(-) bacillus - Granuloma inguinale: chronic, superficial ulceration of genitalia and inguinal and perianal regions - lesion is granulation tissue--macrophages, plasma cells, neutrophils and lymphhocytes - Donovan bodies: interspersed macrophages containing bacteria - genital elephantiasis: obstruction of lymphatics--thickening of skin and edema (NO BUENO)

Answer 41

- Caused by Rickettsia Typhi - Transmitted by flea; rodent pool. - Similar phenotype to epidemic louse-bourne typhus, but less dangerous. -Flea feces can be inhaled--pulmonary infection

Answer 42

- similar to smallpox, milder. - fever, headache, lymphadenopathy, malaise, myalgia, back ache.

Answer 43

- gram(-) coccobacillus, facultative anaerobes - fecal-oral route and contaminated water + milk. - painful diarrhea - enerocolitica: contaminated meat; proliferates in ileum and invades mucosa--necrosis and ulceration of Peyer patches--fever, diarrhea (bloody), and abdominal pain (can be confused with appendicitis); rare septicemia - 50% mortality rate in those persons - pseudotuberculosis (Far East scarlet-like fever): contact with infected animals, penetrates ileal mucosa, localizes in ileal-cecal lymph nodes and causes abscesses and granulomas in lymph nodes, spleen, and liver--fever, diarrhea, and abdominal pain (appenicitis mimic)

Answer 44

- gummas in skin, airways, bone - transmission is mouth-to-mouth, breast-to-mouth, or utensil-to-mouth - usually begins in childhood as a small mucous patch, often on the interior of the mouth, followed by the appearance of raised, eroding, Pyogenic lesions on the limbs and trunk. Periostitis (inflammation) of the leg bones is commonly seen, and gummas of the nose and soft palate develop in later stages. - Mediterrenian/West Africa

Answer 45

-Epidemiology: Common in children under 3 years. Spread from person to person through respiratory aerosols and secretions. Highly contagious. Isolated from 10% of young children with acute respiratory tract illness. -CROUP Pathology: Infect and kill ciliated respiratory epithelial cells and cause inflammatory response. Extends to lower respiratory tract in young children causing bronchiolitis and pneumonitis. Clinical Features: Local edema of laryngotracheitis compresses upper airway to obstruct breathing and cause croup (laryngotracheobronchitis causing inspiratory stridor and barking cough). Causes fever, hoarseness, and cough. Symptoms mild in adults.

Answer 46

- SARS-associated coronavirus (SARS-CoV) from bats. - aerosol respiratory spread -alveolar damage (multinucleate cells without viral inclusions) -fever, headache, cough, dyspnea + some liver involvement (rare) - higher fatality in elderly

Answer 47

- infects lymphocytes and monocytes--Infectious Mononucleosis - symptomatic in immune suppressed patients (as is EBV) - encephalitis, pneumonitis, GI hemmorhage

Answer 48

- Light or non-productive cough. - Non-lobar, very small localizations. “Patchy consolidation” often in lower lung. - Caused by unexpected organisms (Not: Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis) - Caused by atypical bacteria, viruses, fungi, - smallest free-living prokaryotes

Answer 49

- obtain nutrients from keratin--common and benign - Athlete's foot or tinea pedis - Ringworm of the body or tinea corpora - Facial ringworm or tinea faciei - Blackdot ringworm or tinea capitis - Scalp ringworm or tinea capitis - Ringworm of the hands or tinea manuum - Ringworm of the nail, Onychomycosis, or tinea unguium

Answer 50

- paired, bean-shaped, gram(-) cocci - epidemic in crowded areas (military barracks) - P2P spread: respiratory droplets - confined to CNS or disseminated - fulminant fever, stiff neck, headache - meningococcal sepsis: fever, shock, mucocutaneous hemmorhages, diffuse vascular endothelium damage, petechiae, purpura - Rare: vasculitis, thrombosis--Waterhous-Friderichsen Syndrome (adrenal hemorrhagic necrosis)

Answer 51

- Transmission: Water w/ animal urine contacts breaks in the skin. - Usually mild and self-limited, sever forms cause hepatic and renal failure - Leptospiremic phase: 1-2 weeks of nonspecific fever, shaking chills, headache, myalgia that resolve on their own - Immune phase / Weil disease: 3 days after the leptospiremic phase, symptoms return with vasculitis, hemorrhage, meningitis (CNS pleocytosis), liver and kidney failure, shock and death. - Mortality of Weil disease is 5-30%

Answer 52

- Epidemiology: Present worldwide--disease of childhood. Highly contagious--infects 90% of exposed with 60-70% showing symptoms. Live attenuated viral vaccine prevents mumps. - Pathology: Viral infection of respiratory epithelium--necrosis. Disseminates through blood and lymphatic systems to salivary and parotid glands, CNS, pancreas, and testes. 50% cases involve CNS. Epididymoorchitis (unilateral; no sterility) present in 30% males (swollen to three times normal size)--causing local infarctions. Swollen glands and ducts lined by necrotic epithelium and interstitium infiltrated by lymphocytes. - Clinical Features: Fever and malaise followed by painful swelling of salivary glands, one or both of parotids. Symptomatic meningeal involvement manifests as headache, stiff neck, and vomiting. Prior to vaccination, mumps was leading cause of viral meningitis. Patients exhibit elevated serum amylase levels though sever pacreatitis is rare.

Answer 53

- reservoir: many species of mammals and birds--rare spread from animal to human - spread: unpasteurized milk and dairy products - evades intracellular + extracellular host responses: acidic phagosome activate listeriolysin O exotoxin--escape into cytoplasm and usurps cytoskeleton to form portrusions to dock with other cells (spread without staying in extracellular environmentz) - Pregancy listeriosis: lead to abortion or premature delivery - Septicemic listeriorsis: severe febrile illness in immunocompromised--shock and DIC: death without treatment (heavy duty antibiotic course needed) - Self-limited in healthy host

Answer 54

- aka Carrion's disease - gram(-) pleomorphic bacteria - vector: sandflies of Peru, Ecuador, Colombia - Oroya fever: acute hemolytic anemia--untreated leads to 40% mortality rate - verruga peruana: dermal eruptive phase--chronic skin condition that is self-limited and follows acute anemic phase

Answer 55

- a.k.a Tropical Foot, fusospirochetal infection - Follows trauma (lesions) in the tropics, malnutrition is a factor. - Painful leg legion with necrosis, sloughing of skin, and gray putrid exudate -May be complicated by tibial osteomyelitis and squamous cell carcinoma - Deep wounds that persist for years, often need reconstructive surgery to fix

Answer 56

- Inhaled- natural reservoir is pigeon droppings - Impaired cell-mediated immunity common (AIDS, hodkins disease, leukemia) - CNS = site of primary infection--meningitis. Also causes progressive pulmonary disease - Fatal without treatment - Proteoglycan capsule is critical for virulence, - stains poorly with H&E - stains with mucicarmine - India Ink stain of CNS infection

Answer 57

-Most important human helminthic infection, very disabling. -Intense inflammatory response, damage to nearby tissue, usually Liver, GI, or bladder, where it causes granulomas and dysregulated growth (polyps in colon, sq cell carcinoma in bladder). -Asexual reproduction in snail. -Penetrates human skin as schistosomula. -Lays eggs: These cause the inflammatory response. Diagnosed based on eggs in feces. -Generally self-limited

Answer 58

- filamentous, anaerobic, Gram(+) commensual saprophytes present in oropharynx, GI tract, vagina--requires trauma to cause disease - Cervicofacial: jaw injury or after dental surgery--leads to purulent abscesses in jaw. "lumpy jaw" -form sulfur granules made of Splendore-Hoeppli material (tangled masses of branching filaments in polysaccharide protein matrix) - Sinus tracts that penetrate lobe to lobe in pulmonary infections - progressive, slow growing (anaerobic), disease that is well controlled by antibiotics - Fatal if untreated

Answer 59

- Spreads by aerosols from infected water (or infected food, soil) - Immunocompromised older people (⅓ of AIDS patients!). COPD predisposes. - Begins in lungs - causes TB like pulmonary cavities and caseating granulomas (but slow progressing)-years to decades. Macrophages engulf (but dont kill) bugs, then spread throughout body - Antibiotics may control but not cure.

Answer 60

- Spread via respiratory tract and secretions (person-person) -Necrosis of respiratory epithelium, with predominate lymphocytic infiltrate. - Warthin-Finkeldey giant cells (up to 100 nuclei). - fever, rhinorrhea, cough, and conjunctivitis. -Progresses to characteristic mucosal and skin lesions (Koplik spots) develope -Subacute sclerosing panencephalitis (SSPE) -more deadly in immunocompromised

Answer 61

- most common STD - Intracellular, cant make ATP -Elementary body attached to cell and becomes endocytosed - Reticulate body becomes active inside cell, pirates the cell machinery. - Genital and Neonatal Infections - Serovars D through K -Asymptomatic in approx 60% women. - Inflammation of GU tracts, exudate, PID - Generally non lethal, can cause permanent damage to reproductive system. - Lymphogranuloma Venereum - Serovars 1 through 3 - Buboes or abscesses in the groin (inguinal) region where draining lymph nodes are located, progress to necrotizing lymphadenitis. - Often seen with HIV. - Trachoma - Serovars A,B,C - Leading cause of blindness in underdeveloped. - Neonatal exposure from mom. - Effects eyes: characteristic roughening of the inner surface of the eyelids. -Painful, Can lead to visual impairmnent.

Answer 62

- Not common, may be inhaled, ingested, or inoculated - M. kansasii - granulomatous disease similar to MAI in older people - M. scrofulaceum - granulomatous, cervical lymphadenitis in young children - M. marinum - granulomatous or pyogenic, localized skin lesions - from water (pools) - M. chelonae or fortuitum - painless abscesses from trauma that ulcerate and then heal

Answer 63

- Coxiella burnetii - From animals--inhalation of aerosolized dropletts -phagocytosed and proliferation inside macrophages. - Typically a self-limited systemic infection, particularly lungs and liver. - Granulomatous hepatomegaly.

Answer 64

- aerobic, pleomorphic, gram(-) coccobacillus, nonencapsulated, capsulated(Type B): most virulent - P2P spread: respiratory droplets and secretions - Normal flora of oropharynx -pyogenic infection, MENINGITIS (#1 cause in - broncopneumonia, epiglottitis (obstruct airway), septic arthritis (bacteremic), facial cellulitis (bacteremic) - vaccine: nearly eliminated infantile meningitis

Answer 65

- Facultative intracellular parasites causing chronic disease, which usually persists for life. - four types: goats/sheep, cattle, swine, dogs - enter through lungs, through skin, oropharynx - produces UNDULANT FEVER (waxes and wanes) - multiply in macrophages (lymph nodes, spleen, liver): multi-organ granulomas - common complications: spondylitis of spine, meningitis, endocarditis--treat with tetracycline -usually self-limited. mortality

Answer 66

- penetrate human epidermis on contact-enter venous circulation - Duodenale = Asia / Mid East / Africa - Americanus = Americas, Southeast Asia, Subsaharran africa. - GI inflammation, iron deficiency anemia - Most common cause of chronic anemia worldwide.

Answer 67

- Gram-positive, endospore-forming, rod-shaped bacterium - spore form in dead animals/soil and reservoir in goats/sheep/cattle/dogs/pigs/horses - spread through inhalation, breaks in skin, ingestion with germination in body - Malignant pustule: Cutaneous form (most common) papule/ulcer--lymphadenitis can lead to septicemia. (without dissemination--self-limited no complications) - Pulmonary: "woolsorter's disease" respiratory failure and shock within 24-48 hours. - Septicemic: DIC, exotoxin depresses respiratory center--antibiotics ineffective against exotoxin - Gastrointestinal: rare, eating contaminated meat: stomach + bowel ulceration--death caused by fulminant diarrhea and massive ascites

Answer 68

- Active form (trophozoite) in human and feces - Cyst form is usually ingested from environment / fecal oral. - Large Intestine, bleeding more likely. - Invasive =\> May feature bloody / leukocytes in stool, metastisis = \>Liver - ameboma: complication, when amebae invade through intestinal wall-inflammatory thickening of bowel resembling colon cancer.

Answer 69

- sporadic, familial, iatrogenic (from pituitary of cadaveric victims) - neurodegenerative -myoclonus, behavioral changes, dementia - New Variant (vCJD): associated with mad cow - genetic susceptibility (met-met at codon 129 of gene PRNP -fatal (no cure)

Answer 70

- small, aerobic bacillus, gram(-) - respiratory spread: aerosols of infected sources, NOT CONTAGIOUS - pneumoina: Legionaire's Disease (life-threatening) and Pontiac fever (milder, self-limiting) - proliferate inside resident macrophages (granulomatous)--macrophages show eccentric nuclei pushed aside by vacuoles containing L. pneumophila - alveolar necrosis, fever, nonproductive cough followed by hypoxia leading to death. - Silver grain stain, Urine antigen test for diagnosis

Answer 71

- proteobacteria - spread from cat scratches inoculated skin or contact with eye. - Self-limited granulomatous and purulent lymphadenitis. - Parinaud oculoglandular syndrome secondary to conjunctival infection

Answer 72

- obligate anaerobe, spore forming, gram(+) - acute necrotizing infection of small bowel and colon responsible for antibiotic-associated diarrheas (clindamycin most responsible) - Produces cytotoxins A + B - opportunistic--resides in colon flora - pseudomembranous colitis

Answer 73

- Via sandfly bite. - proliferate in macrophages--amastigotes - Tropic/Subtropic, overcrowding. - Skin soars, may progress to disseminated disease, splenomegaly. - kala azar=visceral leishmaniasis "black sickness"-viscera overwhelmed by build up of infected macrophages--disrupts organ architecture with sheets of parasitized macrophages. - kala azar is fatal: Requires treatment if disseminated.

Answer 74

- tropics and subtropics - barefooted agricultural workers

Answer 75

- Inadequatly cooked or encysted meat; PORK. - Survives in human skeletal muscle, myositis (diaphragm, ocular muscles, tongue, intercostals, deltoids, gastrocnemius), calcifications - Classic sign: periorbital edema, swelling around the eyes, which may be caused by vasculitis. - Extreme eosinophilia (\>50% of leukocytes) - May have CNS or cardiac involvement

Answer 76

- aerobic, gram(+) rod, pleomorphic - P2P spread: respiratory droplets + oral secretions - diphteria exotoxin - thick, gray, leathery membranous lesions from respiratory epithelium (necrotic debris, fibrin, neutrophils, - fever, sore throat, malaise -treated with antitoxin and antibiotics - most in western world immunized - peripheral nerve demyelination w/ neural involvement

Answer 77

- Gram(+) cocci - pneumonia, sinusitis, otitis media, meningitis - normal flora in oropharynx (opportunist) - infection follows cold or influenza - insults such as smoking and alcohol - capsule blocks opsonization by complement C3b (inhibits macrophages, antibody needed to kill) -Self limiting, Not severe

Answer 78

-Spreads person to person through intimate contact - respiratory tract or open wounds -Proliferates in areas of lower body temperature (hands and face) -Infection occurs in 5% of exposed people and is either tuberculoid or lepromatous Tuberculoid = Moderate: few lesions, dermal granulomas with sensory loss (not caseous). Reflects appropriate TH1 activation Lepromatous = Severe: foamy macrophages act as incubators and form globi. Form diffuse, tumor like lesions of skin, eyes, testes, nerves, lymph nodes and spleen. Results from deficient TH1 activation.

Answer 79

- spirochete, invade macrophages - Skin-to-skin transmission - Mexico, Central America - Colored spots, scaly/flakey, disease limited to the skin; may leave behind areas of hyperpigmentation

Answer 80

- HSV1: oral secretions - HSV2: genital secretions - painful ulcerating lesions on skin or mucous membranes - Herpes encephalitis and hepatitis (rare HSV1) - neonatal Herpes--serious complication of maternal genital herpes (high mortality) - acyclovir effective

Answer 81

- antigenically diverse, aerobic (facultatively anaerobic), gram(-) rod, most commensal and opportunistic - synthesize vitamin K2, virulence after plasmid transfer - 90% of all urinary tract infections -bladder mucosa infection--dysuria, pyuria (leukocytes in urine) - Immunocompromised: Pneumonai, sepsis - neonatal meningitis: colonizes vaginal canal - Four strains: - ENTEROTOXIGENIC: traveler's diarrhea from contaminated water and food, self-limited (Africa, Latin America)--produce 3 enterotoxins--secretory dysfunction of small bowel (one similar to cholera-adenylyl cyclase, other acts on guanylyl cyclase) - ENTEROPATHOGENIC: diarrheal illness in tropical regions among infants and children, spread from contaminated food and water, deforms microvilli of intestinal epithelial cells, fever + malaise - ENTEROHEMORRHAGIC: bloody diarrhea, fever, cramping abdominal pain, hemolytic-uremic syndrome (anemia, acute kidney failure, thrombocytopenia), contaminated meat/milk, enterotoxin similar to Shigatoxin - ENTEROINVASIVE: food-borne DYSENTERY, indistinguishable from shigella (similar toxin to shiga toxin)-self-limited, invades and destroys mucosal cells of ileum and colon. abdominal pain, fever, tenesmus (feeling of incomplete defecation), bloody diarrhea. week long illness

Answer 82

- Very similar to coccidiomycosis, granulomatous, but also suppurative pulmonary dissease - Endemic to Midwest, Mississippi river and Ohio river basins, and around the Great Lakes. - Skin (\>50%) and bones (\>10%) are most common sites of extrapulmonary involvement. - Usually self-limited (1/3 of patients)

Answer 83

- Epidemiology: spreads by oral-fecal route. Most common amongst children. siblings, parents, playmates, food, water, and surfaces face contamination. 6 months to 2 years is peak age of infection. (all infected by age 4). 100 deaths in young children in US. 1 million deaths worldwide. - Pathology: confined to duodenum and jejunem, where there is shortening of intestinal villi and mild infiltrate of neutrophils and lymphocytes - Clinical Features: Vomiting (2-3 days duration), fever, abdominal pain, and profuse watery diarrhea (5-8 days duration). Without fluid replacement, diarrhea can produce fatal dehydration in young children.

Answer 84

- Caused by Rickettsia prowazekii, - Transmitted by lice, often during disasters, war, or in prisons; human pool. - Obligate intracellular pathogen - Early stage = Febrile - Later = A rash begins on the chest (infects capillary endothelial cells) about five days after the fever appears, and spreads to the trunk and extremities.

Answer 85

- Epidemeology: 10-40 million annual cases for 35,000 deaths. Highly contagious and epidemics spread world wide. Hemagluttinin (H) and Neuraminidase (N) designate serotype. - Pathology: Necrosis and desquamination of ciliated respiratory tract epithelium--lymphocytic infiltrate. infection of lungs leads to necrosis and sloughing of alveolar lining cells. - Clinical Features: Rapid onset of fever, chills, myalgia, headaches, weakness and nonproductive cough. Upper respiratory infection Deaths from both influenza and its complications. Vaccine 75% effective in preventing influenza.

Answer 86

- Epidemic fever disease from lice, caused by Borrelia recurrentis: high untreated mortality - Endemic version is from ticks, many species - General symptoms: fever, lethargy, arthralgia, headache, myalgia, petechiae -More specific symptoms: splenomegaly with miliary microabscesses, hemorhages, hepatomegaly because the spirochetes live in liver sinusoids → inflammation - Sickness comes and goes abruptly in 1-2 week long waves, each time the duration is shorter and symptoms are milder. - Spirochetes also change their antigenic coats in between each febrile period - can be fatal

Answer 87

- natural flora on skin--innoculation following injury - leading cause of infective endocarditis -furuncles, carbuncles, scalded skin syndrome (desquamantion), osteomyelitis, bacterial arthritis - Septicemia, TSS, food posioning, - MRSA-antibiotic resistance plus virulence factors (toxins + proteolytic enzymes) encoded on plasmids.

Answer 88

- penetrate human epidermis - most cases asymptomatic, lethal disseminated disease in immunocompromised persons. - reproduce in human hosts-autoinfection (rhabditiform larvae become infective filariform within host's intestine and repenetrate perianal skin--new parasitic cycle - Immunocompromised: autoinfection greatly increased-penetrate intestinal walls and disseminate leading to ulceration, edema, and severe inflammation leading to sepsis from gram(-) bacteria-FATAL

Answer 89

- gram(-) bacillus, histology looks like school of fish - P2P: sexually - Chancroid: leading cause of genital ulcers in 3rd world countries (facilitate spread of HIV) - opportunistic: enters through breaks in skin - painful, unilateral, suppurative, inguinal lymphadenitis (bubo) - erythromycin: effective treatment

Answer 90

- Pathology: necrotizing bronchitis and bronchiolitis, with sloughed epithelial cells and inflammatory infiiltrate (lymphocytic) fill damaged bronchioles. Interstitial pneumonia is characterized by areas of consolidation with extensive necrosis, hemorrhage, and mononuclear inflammatory infiltrate. Intracellular inclusions, smudge cells and Cowdry type A inclusions involve bronchiolar epithelial cells and alveolar lining cells. - Clinical Features: necrotizing bronchitis and bronchiolitis. Adenovirus type 40 + 41 infect colonic and small intestinal epithelial cells--cause diarrhea in both immunocompetent and compromised victims. AIDS patients susceptible to Adenovirus type 35--urinary tract infections.

Answer 91

- P2P spread (chronic carriers commonly old women with gallstones or biliary scarring), and contaminated water/food--dairy and shellfish, oral-fecal route rarer - granulomatous infection: proliferation inside infected macrophages - Typhoid fever (SEVERE): degeneration of intestinal epithelium brush border (Peyer patch hypertrophy as well)--capillary thrombosis with ulcerated bowel tissue leading to infectious peritonitis; Systemic dissemination: focal granulomas in liver, spleen (typhoid nodules-macrophages with ingested bacteria,erythrocytes, dead lymphocytes) - 10-14 day incubation period - Signs: Bacteremia/invasion: daily increase in temperature (IL-1 + TNF), malaise, arthralgias, abdominal pain--Fastigium: fever/malaise increase--septicemia from release of endotoxin from dead bacteria and hepatomegaly and splenomegaly. Fever abates over weeks to months -10-20% mortality in untreated patients (complications including pneumonia) - Typhoid antitoxin curative if given within 3 days of fever onset.

Answer 92

- Gram(+) cocci - Neonatal Pneumonia, meningitis, and sepsis - 30% infected infants die (1000's infected yearly) - Normal vaginal flora in 10-30% women - spread to infant through birth canal - Risk factor is low level of maternal IgG antibodies

Answer 93

- Gram(-) coccobacillus - highly contagious, P2P: respiratory aerosols - tracheobronchitis with necrosis of ciliated respiratory epithelium (acute inflamed response) - Whooping cough: paroxysmal stage - catarrhal stage: upp resp illness w/ low fever, runny nose, conjunctivitis, cough - vaccine: unimmunized--50 million cases w/ 1 million deaths per year. - secondary bacterial pneumonia--causes death

Answer 94

- short, encapsulated, facultative anaerobic, gram(-) rods - necrotizing lobar pneumonia with cavitations - 10% of nosocomial infections: P2P spread - patients with COPD, endotracheal tubes, catheters, and immunosuppressed. - complication from influenza or other viral infections - characteristic THICK MUCOID SPUTIM - can lead to fulminating, deadly septicemia--requires aggressive antibiotic treatment

Answer 95

- spread through skin on contact (dogs and cats major source of of disease) - severe, itching, inflammation

Answer 96

- inheirited, rare disorder - progressive degree of insomnia to sleeplesness - autonomic instability, motor system degeneration, spongiform changes (like CJD)

Answer 97

- neurotoxin present in improperly canned food (blocks acetylcholine release): Don't feed newborns honey - descending paralysis, blurred vision - untreated: lethal - antitoxin- 25% mortality

Answer 98

- Naegleria fowleri “Brain eating ameoba”: free-living, soil ameba - Rare, but almost always rapidly fatal: fulminant disease-fever, nausea, vomiting, headache to deterioration of mental status in matter of hours. - invades via nasal epithelium/olfactory bulbs. - Swimming pools - Neti-pots (for cleaning out your sinuses)

Answer 99

- Mango fly bite transmites loa loa (round worm), which travels to the conjunctiva, where it can be readily seen in patient. - Does not cause blindness - rarely lethal (sudden + diffuse cerebral ischemia) - usually self limited with mild CNS involvement

Answer 100

-spores (conidia) inhaled -Allergic bronchopulmonary aspergillosis: restricted to asthmatics, spores can germinate in airways and cause long-term antigen exposure → exacerbation and infiltrates -Aspergilloma (fungus ball): Occur in old TB cavities. Cavity wall is collagenous connective tissue with lymphs and plasma cells. Usually left untreated if asymptomatic. -Inasive Aspergillosis: Occurs when neutrophil count is low (steroids, leukemia). Produces lung and pleural infarcts, but often spreads to blood and causes disseminated infec tion and thrombosis. Usually fatal, antifungals may help.