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108 Cards in this Set
- Front
- Back
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Gram Stain
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Pos = Blue
Neg = Red |
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Enzyme that catalyzes formation of peptidoglycan aka?
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Transpeptidase
Penicillin Binding protein |
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Teichoic Acid
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Antigenic determinant of many gram-positive bacteria present in gram-positive cell walls.
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Murein Protein
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Unique lipoprotein present in gram-neg cell wall to attach to outer membrane.
* No teichoic acid |
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LPS & Components
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Found in outermost portion of gram-neg bilayer.
1) O-antigen or O-specific side chain 2) Water Soluble core polysaccharide 3) Lipid A - Gram-neg Endotoxin |
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Gram Positives
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Cocci - Strept & Staph
Bacillus Spore - Bacillus, clostridium Bacillus non-spore - Corynbacterium, listeria |
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Gram Negs
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Cocci - Nisseria
Spiral - Spirochetes Rest are gram-neg rods or plemorphic |
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Flagellum attach to bacteria via
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Basal body, attaches to cell membranes.
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Bacterial Adhesins
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Pili for attachment to produce virulence
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Exosporium
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Outer layer of endospore
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Bacterial with Exotoxin subunits
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Bacillus anthracis
Clostridium botulinum Clostridium tetani Vibrio Cholera Corynbacterium Diptherae Shigella Bordetella pertussis Pseudomonas |
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4 bacteria that produce exotoxins that increase levels of cAMP
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Cholera
Anthrax Ecoli Pertussis |
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Parts of Spore
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Core - Contains DNA, ribosomes, enzymes, and everything cell needs
Cortex - Modified Peptidoglycan with fewer cross linkages Coat - Protein layers that confer resistance to most chemicals |
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Transformation
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When naked DNA fragments released from cell lysis is taken up by an another competent bacteria
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Transduction & types
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When a bacteriophage carries a piece of bacterial DNA from one to another
General is from a virulent phage that lyses a bacteria with a piece of DNA the same size as viral DNA Specialize is from temperate phages and results from error in splicing where piece of bacterial DNA will be cut & replicated to be packaged into virus |
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Conjugation
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Sexual union between bacterial with F plasmid & one without
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Transposons
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Mobile genetic elements of DNA that can insert themselves into a donor chromosome without having DNA homology
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6 types of disease caused by Group A beta-hemolytic Strep
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aka Strep Pyogenes
Scarlet fever Skin infection Streptococcal pharyngitis Strept toxic shock syndrome 2 delayed: Rheumatic fever Glomerulonephritis |
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Scarlet Fever
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Caused by pyrogenic or erythrogenic toxin from Group A Beta-hemo strep. Causes fever with scarlet red rash starting from trunk to extremities sparing face
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Rheumatic Fever age group & symptoms
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Strikes children 5-15 following untreated beta-hemo Group A strep pharyngitis.
Fever, myocarditis, arthritis, chorea, subcutaneous nodules, rash called erythema marginatum |
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Group B Strep
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aka Strep Agaelacteae
Beta-hemolytic 25% of women carry this bug vaginally & transmitted during delivery Neonatal meningitis, pnemonia & spesis |
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Viridians Strep
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Huge group, mostly alpha hemolytic
Causes Dental infection, endocarditis, & abcesses |
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Group D strep
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Alpha Hemolytic
Enterococci - Found in GI & prey on weak hospitalized pts & Non Entero cocci -Strep Bovis & Equinus -Bovis in blood - Cancer in Bowel |
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Pneumococcus
Optochin? |
Streptococcus Pnemoniae
- No lancefield antigen - Diplococci Optochin positive, but Strep Viridians is negative Most common cause of otitis media in children & bacterial meningitis in adults |
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Coagulase test
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Staph Aureus is Positive
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Staph A exotoxins
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Exfoliatin - cause scalded skin syndrome
Enterotoxin - Gastroenteritis TSST - toxic shock syndrome toxin, hybrid between food poisoning & streptococcal scarlet fever |
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Direct organ invasion of Staph A
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1) Pnemonia
2) Acute bacterial endocarditis 3) Osteomyelitis 4) Arthritis 5) Meningitis 6) UTI 7) Sepsis 8) Skin infections |
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TSST
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Toxic shock syndrome toxin released by Staph A from super absorbent tampons
Causes hybrid between food poisoning & Scarlet fever |
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Staphylococcal Scalded skin syndrome
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Caused by a Staph A strain that releases exfoliatin A & B
- Usually in neonates & causes cleavage of middle epidermis |
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Acute Endocarditis
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Caused by both Staph A & Strep viridians & Group D strep which has a more gradual onset.
Staph Aureus acute endocarditis is violent destruction of heart valves with sudden onset of high fever, chills & myalgias |
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Staph Epidermis
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-Coagulase Neg
-Normal skin flora, but can infect hospitalized patients -Infects prosthetic devices |
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Staph Saprophyticus
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-Second only to E.Coli for UTI in sexually active young women.
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Spore forming rods & They oxygen tolerance
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Bacillus - Aerobic
Clostridium - Anaerobic |
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2 Pathogenic species of Gram Positive Spore forming Rods
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Bacillus Anthracis - Anthrax
Bacillus Cereus - Gastroenteritis |
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pXO1 & pXO2
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Anthrax virulence factors
pXO1 - Edema Factor (EF) increases cAMP which impairs neutrophils & causes edema - Protective Antigen (PA) - Enables entry of EF into phagocytes -Lethal factor (LF) - Zinc metalloproteinase that inactivates protein kinase, stimulates TNFa & IL1b from macrophage to cause death pXO2 - encodes poly-glutamyl capsule(Only one composed of protein) to inhibit phagocytosis |
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Anthrax transmission & Vaccine
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Via contaminated products made of hides & goat hair
Can infect via: Skin abrasion - Local necrosis & black lesion with a rim of edema "malignant pustule" Pulmonary - transported by macrophages to mediastinal nodes & cause hemorrhage, pleural effusions GI - Exotoxin causes necrotic lesion in intestine, vomiting, bloody diarrhea, often death Vaccine via protective antigen (PA) |
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Bacillus Cereus
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- Motile, non-encapsulated, & resistant to penicillin
-Causes food poisoning via 2 enterotoxins heat-labile toxin - similar to enterotoxin of cholera & LT from E coli, nausea, vomiting diarrhea for 12-24 hrs Heat-stabile toxin - Similar to enterotoxin of Staph A, short incubation with severe nausea & vomiting, but limited diarrhea |
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Clostridiums
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Anaerobic, spore forming gram positive rods,
Botulinum, tetani, perferinges, dificile |
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Botulism definition & types
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Releases neurotoxin that blocks release of ACh from presynaptic nerves causing flaccid paralysis
Adult botulism - Eating smoked fish or home-canned vegetables with botulinum spres that landed on them. If uncooked and placed in a anaerobic enviornment, neurotoxin is made and eaten Infant botulism - when babies ingest botulism spores. Intestines are colonized, and toxins are released Wound botulism - puncture wounds or deep infections makes good environment for botulism growth. Presentation same as adult botulism but without GI symptoms |
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Tetanus Definition & symptoms
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-Follows puncture wound contaminated with spores
-Releases tetanospasmin, which is transported from NMJ to CNS to stop inhibitory interneurons -Presents with muscles spasms & trismus or lockjaw, with risus sardonicus |
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Tetanus prevention & protocol
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Immunization with formalin inactivated toxin every 10 yrs
1) last shot more than 10 yrs ago is given another booster 2) Never been immunized is immunized & given preformed antibodies to tetanus toxin 3) Having developed tetanus 5 steps - neutralize toxin with immune globulins - Give immunization booster - Clean wound to remove spores - Antibiotics - Muscle relaxants, ventilator |
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Clostridium Perferinges
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aka gas gangrene
- Spores found in soil & matures in anaerobic conditions & produces gas - Affects wounded soldiers - 3 classes of infection 1) Cellulitis - Crepitus(crackling, spongy skin due to pockets of gas) within necrotic skin 2) Clostridial myonecrosis - destroys mucles & forms pockets of gas 3) Diarrheal - can germinate in foods like meat, poultry, leading to watery diarrhea |
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Clostridium Difficile
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aka Pseudomembranous Enterocolitis
- Pathogen responsible for antibiotic-associated pseudo-membranous colitis. - Antibiotic wipeout of normal flora causes pathogenic clostridium difficile to superinfect colon - Characterized by severe diarrhea, abdominal cramping, & fever |
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The Gram positive non spore forming rods & they age group
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Corynbacterium & Listeria
Pediatric age group |
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Corynbacterium Diptherae transmission
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Colonizes pharynx & forms grayish pseudomembrane. Releases exotoxin into blood & damage heart & neural cells by inhibiting protein synthesis
2 subunits for exotoxin which is a "human antibiotic" |
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Listeria Monocytogenes Transmission, virulence factors, diseases
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Acquired from contaminated foods: Milk, soft cheeses, butter, deli meats
Grows at low temperatues - Major virulence factor is listeriolysin O that allows escape from phagolysosomes LIST: Pregnant women - third trimester, can cross placenta Neonates - Can be infected in utero or moving through vagina Meningitis in elderly & immunocompromised - Second most common cause of meningitis after pneumococcus |
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Meningococcus, Virulence factors(5), & Diseases
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Neisseria Meningitidis
- Antiphagocytic capsule - LPS endotoxin, causes blood vessel destruction & petechiae - IgA1 protease cleaves IgA - Extracts iron - Pili attaches to human nasopharynx & undergo variation - Meningococcemia - Intravascular multiplication results in fevers, chills, arthralgia, petechial rash - Fulminant meningococcemia - This is sepsis & tachycardia with hypotension results, with DIC & coma -Meningitis - Most common form of meningococcal disease striking infants <1yr old |
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Gonoccocus virulence factors & diseases
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Neisseria gonorrhoeae - second most common STD behind chlamydia
- Pili - Undergo recombinations to protect, helps bind to host cells, & holding so close it avoids phagocytosis - Outer membrane protein porins & Opa proteins both help invade epithelial cells Men: penetrates mucous memb of urethra. Some are asymptomatic, others have purulent discharge & painful urination. MSM can cause rectal gonococcal infection Women: More likely asymptomatic, but infection of cervix can lead to PID. Fever, lower abdominal pain, abnormal menstruation. Can spread to uterus, fallopian tubes, or ovaries Men & Women: - Gonococcal bacteremia - Skin lesions, fever, joint pains, pericarditis, etc - Septic arthritis - Acute fever with swelling of 1-2 joints. Gonococcal arthritis is most common form of septic arthritis in young sexual adults Infants: Transmitted to infant during birth. Result in ophthalmia neonatorum. Given erythromycin drops for chlamydia & Neisseria |
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PID
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Result of Gonoccocal or Chlamydial infection of cervix, leading to infection of uterus, tubes, & ovaries
Complications include 1) Sterility 2) Ectopic pregnancy 3) Abcesses 4) Peritonitis 5) Peri-hepatitis |
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Lactose fermentation
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E.coli & most enterobacteria do. But Salmonella, Shingella, Pseudomonas aeruginosa do not
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Major surface antigens of Enterics and Misc
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O antigen - Outermost portion of LPS
K antigen - covers the O antigen H antigen - Makes up subunits of flagella so only motile bacteria has. Kleibsella & Shingella doesn't have & Salmonella's changes periodicly |
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Pathogenesis of enterics & Details & Examples
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Diarrhea with or without systemic invasion
Others such as UTI, pnemonia, sepsis Diarrhea types - No cell invasion - Watery diarrhea w/o systemic symptoms. EnteroToxigenic Ecoli, Cholera - Invasion of intestinal epithelium - Leukocytes & blood in stool & fever. Enteroinvasive Ecoli, Shingella, Salmonella enteritidis - Invasion of Lymph nodes & blood - Aside from abdominal pain with bloody diarrhea, theres systemic fever, headache & white cell elevation. Can lead to sepsis. Salmonella typhi, Yersinia Enterocolitica, Campylobacter jejuni. |
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E. Coli pathogenicity
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Gains virulence factors via plasmid exchange:
1) Mucosal Interaction - Mucosal adherence with pili - Ability to invade intestinal epithelial cells 2) Exotoxin - HL & HS toxin - Shinga-like toxin 3) Endotoxin: LPS 4) Iron binding siderophore Diseases: Diarrhea, UTI, Neonatal meningitis, Gram neg sepsis: Common in hospitalized pts |
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Diarrhea producing E. Coli
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EnteroToxogenic E.coli (ETEC) - Traveler's diarrhea from E.coli with colonization factor. Heat-labile toxin like cholera, and heat-stabile toxin. Inhibits Na+ & Cl- reabsorption & stimulates Cl- & HCO3- secretion. Rice water diarrhea like cholera
- Enterohemorrhagic e.coli(EHEC) - Secrets shinga-like toxin which inhibits protein synthesis at 60S. Intestinal epithelial cells die & hemorrhagic colitis - Bloody diarrhea with abdominal cramps Enteroinvasive E.coli (EIEC) - Same as that caused by shingella. Gains ability to invade, causes hemorrhagic colitis & fever due to shinga-like toxin production in cell. |
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Other E. Coli diseases 4
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UTI - Most common cause ahead of Staph Saprophyticus
Meningitis - Second to group B strep as common cause for neonatal meningitis Sepsis - Most common cause of gram neg sepsis, succeptible pts, LPS is cause Pnemonia - Common cause of hospital pnemonia |
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Klebsiella Pneumoniae virulence, disease & symptoms
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Encapsulated with O antigen but no H antigen.
- Second leading cause of sepsis after E. Coli, infecting alcoholics and hospitalized pts -Pneumonia with bloody sputum & high mortality rate |
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Proteus Mirabilis
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AKA urea splitting protease
-Very motile -Common cause of UTI & urine will be basic due to proteus' ability to split urea into NH3 & CO2 |
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Enterobacter
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Normal Part of flora, sometimes responsible for hospital infections
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Serratia
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Notable for production of bright red pigment
- Causes UTI, wound infections, or pneumonia |
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Shigella
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Non motile & does not produce H2S or ferment lactose. Ecoli ferments lactose, & Salmonella produces H2S & non-lactose
Releases Shinga toxin which is like EIEC, & has subunits that inhibit protein synthesis |
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Salmonella Characteristics & Virulence, Transmission, & Infection
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Non-lactose, H2S positive, Motile
- Vi antigen which surround O antigen to prevent antibody binding. Just like K antigen. - Lives in animal intestines & infection is via contamination of food with animal feces Typhoid fever- aka enteric fever. Goes a step beyond EIEC & shigella to invade lymph nodes & many organ systems. Can survive in monocytes. Arises 1-3 wks after exposure, includes fever, headache with pain over lower right quadrant, mimicking appendicitis. Red spots on abdomen. Carrier state - Some who recover from typhoid fever carry salmonella in gall bladder & constantly excreting bacteria Sepsis - Cruising in bloodstream can infect lungs, brain or bone. Gastroenteritis - Most common salmonella infection. Nausea, abdominal pain, diarrhea watery or trace blood. Half have fever. |
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Yersinia enterocolitica transmission, Pathogenesis
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- Lives in animals, but is transfered via fecal oral route rather than flea bite like yersernia pestis (Bubonic plague)
- Following ingestion of contaminated milk, or water, develop fever, diarrhea, severe lower right quadrant pain. - Invasion with virulence factors that allow binding to intestinal wall & blood - Enterotoxin - like that of E.coli, & causes diarrhea |
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Vibrio Cholera transmission, toxin & disease
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-Transmitted fecal oral route usually from fecal contaminated water. Multiply within intestine & cause same disease as ETEC but more severe.
Choleragen - same mechanism of action as LT toxin of E. Coli. Has subunits, A enters cell & activates G protein which stipulates Adenylate cyclase to produce cAMP. Na & Cl are dumped and not reabsorbed. - Diminished pulse, sunken eyes, poor skin turgor. Death by dehydration |
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Vibrio Parahaemolyticus
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Marine bacterium that causes gastroenteritis after eating uncooked seafood. #1 cause of diarrhea in Japan
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Campylobacter Jejuni transmission & disease
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- Transmission via fecal oral route of domestic animals, pultry & unpasteurized milk
- Fever, headache, abdominal cramps, & bloody diarrhea |
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3 most common causes of Diarrhea in the world
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Campylobacter jejuni, ETEC, Rotavirus
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Helicobacter Pylori
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- Most common cause of duodenal ulcers & Chronic gastritis, second leading cause of gastric ulcers
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Pseudomonas aeruginosa virulence, characteristics & diseases
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- Colonizes & infects sick, immunocompromised patients, & is resistant to almost every antibiotic
- Obligate aerob & non lactose fermenter with a grape like scent - Many exotoxins like exotoxin A which has same mechanism as diptheria toxin. 8 Diseases: Burn wound infection - Significant burn wound infection leading to fatal sepsis Endocarditis - Staph A & Pseudomonas aeruginosa are frequent causes of right heart valve endocarditis in drug users Pneumonia - colonizes lungs of cystic fibrosis pts & immunocompromised Sepsis - high mortality External Malignant otitis media - ear infections in diabetics UTI - polynephritis in debilitated nursing home pts from foleys Diabetic osteomyelitis - Increased foot ulcers infection with Pseudomonas aeruginosa. Also affects drug users & children Corneal infection - in contact lens wearers |
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Bacteroides Fragilis
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- One of the few gram negative bacteria that does not contain lipid A (No endotoxin)
- Lives peacefully in intestine, but if torn, infects peritoneal cavity & forms abcesses. |
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Bacteroides Melaninogenicus
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Causes Periodontal disease & necrotizing anaerobic pneumonias by aspiration of sputum. Lives in mouth, vagina & intestines
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Fusobacterium
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Just like bacteroides melaninogenicus, causes PD and aspiration pneumonias.
- Can also cause abdominal & pelvic abcesses & otitis media |
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Gram negative rods aquired through respiratory tract
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Haemophilus influenza, Bordetella pertussis & Leigionella pneumophilia
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Haemophilus Influenzae description, virulence, Specifics, & preventions
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- Needs blood for hematin & NAD+ & loves to attack lungs of those with a viral influenza. Transmitted via respiratory route
- Polysaccharide capsule designated a,b,c,d,e,f confers virulence. Type b is associated with invasive Haemophilus influenzae disease in children. - Non encapsulated strains can colonize Upper respiratory tract & cause local infection. Cause otitis media in children & respiratory disease in those with lung disease like COPD - 6month to 3yr window to invade children Capsule b = bad 1) Meningitis - Used to be main cause of meningitis 6mth to 3yrs. Most heal but inflammation against LPS leave neurological damage like retardation, seizures, deafness. 2) Acute epiglottitis - Can cause rapid swelling of epiglottis. Following sore throat & fever, child develops stridor & cant swallow. 3) Septic arthritis - H.I is most common cause of septic arthritis in infants. 4) Sepsis - Children btw 6mth & 3 yrs present with fever, lethargy, & loss of apetite. Esp in children with no spleens. Vaccination - Purified type b capsule only worked after 18mth old. Now conjugate with mutant diptheria toxin, meningococcus outer memb protein or tetanus toxoid to activate T-lymphocytes |
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Haemophilus ducreyi & Differential
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- Responsible for the STD chancroid. Classified by unilateral painful genital ulcers with pus.
Separate from: Syphilis - which is bilateral, painless, and no pus Herpes - Painful aswell, but with systemic fevers & myalgias Lymphogranuloma venerum (Chlamydia trachomatis) - Primary ulcer disappears before nodes enlarge |
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Gardnerella Vaginalis
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Formerly Haemophilius vaginalis
- Causes bacterial vaginitis with anaerobic vaginal bacteria. Develop itching of labia, dysuria & fishy vaginal discharge. Look for CLUE CELLS - vaginal epithelial cells with pleomorphic bacilli within cytoplasm |
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Bordetella Pertussis Toxins,
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Whooping cough
4 toxins to attach & damage ciliated cells of trachea & bronchi 1) Pertussis toxin - has subunits with A activates adenylate cyclase to ^cAMP etc. 3 observed effects: histamine sensitization, inc insulin synt, promotion of lymphocyte produc & inhibit phagocytosis 2) Extra cytoplasmic adenylate cyclase - Bordetella pertussis throws adenylate cyclase grenades for phagocytes to eat. Inc cAMP to impair chemotoxis & H2O2 or superoxide generation 3) Filamentous hemagglutinin (FHA) Involved in binding to cells of bronchi. Antibodies are directed against FHA 4) Tracheal cytotoxin - destroys ciliated epithelial cells to impaire clearance of bacteria, mucus, & exudate. Causing violent cough |
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Whopping cough, disease, Vaccination & special
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Caused by Bordetella Pertussis & now affects mostly children <1yr & young adults b/c vaccine only covers for 15 yrs.
- Highly contagious & transmitted via respiratory secretions. Week long incubation followed by 3 states 1) Catarrhal stage - lasts 1-2 wks similar to upper respiratory infection with fevers, runny nose, & mild cough. Most contageous Paroxysmal stage - Fever subsides & 15-25 violent cough attacks per day. Covalescent stage - attacks subside gradually over a month & no longer contagious * Blood will have increase in lymphocyte with modest inc in neutrophil due to pertussis toxin & will seem like a viral Vaccination via DPT - includes heat kill organisms with pertussis toxin, FHA, adenylate cyclase. Combined with inactivated tetanus & diptheria toxins. |
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Leigionella Pneumophilia, transmission, Diseases
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Leigionnaires Pneumonia
Found in natural & man made water environments. Infection via inhaled aerosolized contaminated water. E.g A/C, whirlpool, watertowers. no person to person - Settles in lower respiratory tract & lives to replicate in macrophages. - Can live & replicate in ameobas & biofilm Diseases: 1) Pontiac fever - like influenza, involves headache, muscle ache, fatigue, fever, chills. Resolves in a week 2) Legionnaires disease - very high fevers & severe pneumonia |
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Yersinia, Francisella, Brucella, Pasteurella (5)
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Pasteurella is only first 2
1) All gram negative rods 2) All zoonotic species 3) All very virulent and can infect via insect or animal bite, direct contact, or via inhalation of infected matter. 4) All travel via macrophages to lymph nodes, set up infection and spread to lungs, liver, spleen. 5) Like all faculative intracellular organisms, immunity is cell mediated & injection of bacterial extracts will elicit DTH reaction. |
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Yersinia pestis transmission, whereabouts, virulence, symptoms
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- Rats harbor disease while fleas are the vector. As rats die, fleas search out humans. Can also be aerosolized causing human to human transmission. Now lives in squirrels & prairie dogs in south western US.
- Fraction 1 has antiphagocytic properties, V & W antigens, unique to Yersinia genus, actions are unknown. - Usually infects inguinal nodes which become like eggs, red, hot and painful. Invades lungs, liver, blood and causes fever & headache. Hemorrhages under skin result in blackish discoloration. Hence black death. |
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Francisella tularensis, transmission, diseases
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Causes Tularemia which resembles bubonic plague
- Transmission via contact with wild rabbit or bite from ticks or deerflies. 1) Ulceroglandular tularemia, bite site is ulcerated with a black base. Local lymph nodes become red hot & swollen. Bacteria then spreads to infect other organs. Much like plague, but Tularemia has only 5% mortality & plague has no ulcer. 2) Pneumonic tularemia - Aerosolization of bacteria during skinning & evisceration of rabbits or spread of ulceroglandular tularemia to lungs can cause pneumonia. * Can also invade eyes & GI tract. So virulent only takes 10 to cause disease. |
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Brucella types, transmission, disease
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Causes brucellosis of 4 types
Brucella melitensis - goats Abortus - causes abortions in cows Suis - pigs Canis - dogs Infection via contact with infected animal meat, milk or aborted placentas. Not likely in US so infection means someone in meat industry, vet, farmer or traveler. - Penetrates skin, mucous membranes, followed by lymphatic spread via macrophages. Systemic symptoms like fever, chills, loss of appetite etc. Fever usually peaks in evening & then gradually declines at night. aka Undulant fever. |
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Pasteurella Multocida
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- Colonizes mouths of cats causes most frequent infection after cat or dog bite.
- Do not close suture after cat or dog bite. It would allow pasteurella multocida to grow & infect local joints & bones |
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ATP/ADP translocator
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Found in obligate intracellular energy parasites like Chlamydia & Rickettsia. However, Rickettsia does have some ability to create ATP but Chlamydia does not.
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Chlamydia general classification, features & infectious cycle & organisms
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- Has inner & outer memb & Classified as gram neg b/c it stains red but does not peptidoglycan or muramic acid.
- Likes to associate with columnar epithelium, thus infects conjunctivitis, cervicitis, & pneumonia - Metabolically inert elementary body (EB) enters via endocytosis columnar epithelial cells. - Multiplies & becomes Initial Body or reticulate body - Some IB turn back into EB and infect other cells 3 species cause disease: Chlamydia trachomatis Chlamydophila Pssitaci Chlamydophila Pneumonia |
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Chlamydia Trachomatis diseases
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- Most common STD and Primarily affects eyes & genitals
Trachoma - Type of conjunctivitis thats leading cause of preventable blindness in povery & underdeveloped. Transmitted via hand-to-hand transfer via infected eye secretions & slow blindness in 10-15 yrs. Inclusion conjunctivitis - Babies delivered through infected birth canals develop conjunctival inflammation with yellow purulent discharge & swelling of eyelids. Diagnose via intracytoplasmic inclusion bodies in cells from palpebral conjunctival surface. Infant Pneumonia - Passage through birth canal can also lead to pneumonia between 4-11 wks. Diagnose via IgM antibodies. Urethritis - Nongonococcal urethritis or NGU is caused predominantly by C. trachomatis & Ureaplasma urealyticum. Many asumptomatic but symptoms include dysuria with mucoid discharge. PID - Infection of cervix can lead to PID along with N. Gonorrhoea. Bleeding, pain during sex, nausea, vomiting, fever. PID shuffle. Epididymitis - Chlamydial epididymitis can develop in men & presents with unilateral scrotal swelling, tenderness, pain & fever Other complications Reiter's syndrome: Arthritis of large joints Fitz-hugh-curtis syndrome: infection of liver capsule with right upper quadrant pain, gonoccocal or chlamydial can cause this Lymphogranuloma venerum - Starts with painless papule that goes away. Then bacteria migrate to regional lymph nodes which enlarge over 2 months. May break open & drain pus |
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Chlamydophila psittaci
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-Infects many birds, even parrots. Humans are infected via inhaling feather dust or dried feces.
- 1-3wks after exposure, psittacosis results: Atypical pneumonia with dry cough, fever & less sick. |
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Chlamydophila pneumoniae
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- Strain TWAR stands for Taiwan isolated acute respiratory.
- Transmitted person to person & causes atypical pneumonia in young adults |
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Rickettsia characteristics, diseases
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Small non-motile similar in size to chlamydia & large viruses. Differs in 4 characteristics
1) Needs arthropod vector except Q fever 2) Can reproduce in cytoplasm vs endosomes (intracytoplasmic inclusion bodies) for chlamydia 3) Likes to infect endothelial cells vs columnar epithelium 4) Different diseases: most with high fevers, rashes & headaches Rickettsia rickettsii - Rocky mountain spotted fever presents after tick bite. Characterized by fever, conjunctival redness, headache & rash from extremities spread to trunk. More common in south eastern region. Proliferation in endothelial lining causes small hemorrhages & thrombi to explain conjunctival redness. Often resolves in 3 wks but can cause death. Rickettsia akari - Transmitted via mite on mouse. Causes rickettsialpox, a mild self limited febrile disease with red skin bump at site of infection. Rickettsia prowazekii - Epidemic typhus, transmitted in poverty & crowding via lice. Sudden onset of fever & headache. Pink macules all over body but spares palms, soles & face. Invasion of endothelial cells leads to clotting & gangrene of feet or hands. Resolve by 3 wks but can be fatal Rickettsia typhi - endemic typhus harbored in rats & transmitted via rate flea. Milder symptoms than epidemic Rickettsia tsutsumagushi - Found in asia & southwest pacific. Spread by bite of mite larvae in soil. |
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Bartonella quintana
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- Louse-borne febrile disease during WWI. Spread in trenches by body louse. High feves, rash, headache, severe back & leg pains. 5 day relapses. * Not obligate intracellular organism
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Bartonella henselae
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aka cat-scratch disease
Following cat bite or scratch, regional lymph node enlarge with lograde fever & malaise. Resolves in a few weeks |
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Coxiella burnetii characteristics & disease
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Causes Q fever
- unique to rickettsia due to endospore form. - Resistant to heat or drying, exist extracellular, transmit via ticks & cattle. - Disease via spore inhalation. Pneumonia with fever & soaking sweats. NO RASH |
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Spirochetes special characteristics & species
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1) Move in unique spinning fashion with axial filaments.
2) Has all gram neg characteristics but with additional phospholipid outer memb with few proteins for stealth 3) Axial flagella come out ends of cell wall rather than out of outer membrane. Runs sideways under outer membrane sheath. Periplasmic flagella. 4) Can't be seen with light microscope or grown on ordinary media. Must see with darkfield microscopy 3 genera: Troponema, Borrelia, Leptospira |
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Troponema virulence, transmission, diseases, diagnosis
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- Produce no known toxins or tissue destructive enzymes. Disease is via inflammatory infiltrate.
- Penetrates intact mucous membranes or invading epithelial abrasions. 3 disease stages with latency between stages 2&3 Primary - Painless chancre at site 3-6 wks after initial contact. Regional lymph node swelling. Ulcer highly contagious Secondary - Bacteremic stage, 6 wks after primary chancre heals. Dissemination through body with widespread rash & many organ involvement. Condyloma latum - wartlike lesions in scrotum or vulva. Skin infection in areas of hairgrowth results in bald spots. Fever, weight loss, lymphadenopathy. Latent Syphilis - After 4 yrs relapses disappear, but women can still transmit to fetus. 33% will progress to tertiary syphilis. Tertiary Syphilis - develops over 6-40 yrs, grouped into 3 categories 1) Gummatous syphilis - occures 3-10 yrs after primary infection. Gummas are localized granulomatous lesions that necrose & become fibrotic. Found mainly in skin & bones. Deep gnawing pain 2) Cardiovascular syphilis - atleast 10 yrs after primary in 10% of untreated. Aneurysm forms in ascending aorta or aortic arch caused by destruction of arterioles supplying aorta itself, leading to media layer necrosis. Irreversible 3) Neurosyphilis - occurs in 8% with 4 manifestations - Asymptomatic syphilis with CSF tests positive - Subacute meningitis *High lymphocyte, high protein, low Glucose. - Meningovasclar syphilis destroys blood vessels in brain & meninges causing nerve tissue damage - Tabes dorsalis affects posterior column & dorsal roots. Loss of reflexes, pain & temp sensation. Prostitute's pupil Congenital syphilis: T. pallidum crosses PBB & can infect after 4 months of gestation. Most spontaneously abort. Ones that survive develop early or late congenital syphilis. a) Early - occurs within 2 yrs like adult secondary syphilis. b) Late - Similar to adult with neurosyphilis, bone & teeth involvement. With saddle nose, saber shins, hutchinson's teeth & mulberry molars. CV problems rarely occur. Corneal infection can occur. Diagnose via antibodies against cardiolipin & lecithin VDRL. Or specifically FTA-ABS. |
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3 bacterial infections that lead to high lymphocytes instead of neutrophils.
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Bordetella pertussis, Troponema pallidum, Mycobacterium TB
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Jarisch-Herxheimer Phenomenon
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Mild fever, chills, malaise, headache, myalgia after treatment of syphilis. May occur with most spirochetes.
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Borrelia transmission, diseases, & diagnosis
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Transmitted via insect vector
Borrelia burgdorferi - Seen in NE, Midwest & NW US. Reservoir is in mice & deer. Takes 24 hrs of tick attachment to transfer Lyme disease. Infection cycle much like syphilis & disease divided into 3 stages 1) Early localized stage - Begins after 10 days with skin lesion at site of tick bite (ECM). 2) Early disseminated stage - Involves dissemination to skin, nerves, heart, joints. Multiple smaller ECM on body. Could lead to meningitis, cranial nerve palsies, peripheral neuropathies. Transient cardiac abnormalities. 3) Late stage - 10% untreted will develop chronic arthritis for more than a yr. Could lead to chronic neurologic damage. Memory impairment, irritability etc. Diagnose via biopsy leading edge of rash on ECM. Borrelia Recurrentis - Transmitted via human louse or tick bite sleeping campers in western US. Disseminates via blood, with fever, chills, headaches, & muscle aches. Drenching sweats for 3-6 days followed by 8 day refractory. Relapsing fever due to antigenic variation. Diagnose by drawing blood culture during febrile periods. |
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Leptospira transmission, diseases, diagnosis
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- Found in urine of dogs, rats, livestock & wild animals. Transmission via mucous membrane or abraded skin contact.
2 phases - leptospiremic phase causes fever, headache, myalgia. Immune phase is IgM showing up, with meningismus. Leptospira Interrogans cause Weil's disease or infectious jaundice. Involves renal failure, hepatitis with jaundice, mental status changes & hemorrhage in many organs. Diagnose via culture blood or CSF during first fever, or urine after that. |
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Mycobacterium structure, ID & types
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- Thin rods with lipid laden cell walls
- High lipid content in cell wall makes them acid fast on staining. RED. Only Mycobacterium & Nocardia stain acid fast Mycobacterium Tuberculosis & Mycobacterium Leprae |
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Mycobacterium TB virulence
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1) Mycosides - Made from mycolic acid bound to a carbohydrate. Forming a glycolipid.
2) Cord factor - A mycoside formed by 2 mycolic acids with a dissacharide. Only found in virulent strains of TB, appearing as cords. Inhibits neutrophil migration & damage mitochondria. Might contribute to weight loss phenomenon. 3) Sulfatides - Mycosides that are chord factors with sulfates on the disaccharide. Inhibits phagolysosome fusion. 4) Wax D - Complicated mycoside that acts as adjuvant. |
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TB pathogenesis
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- Primarily affects lung, but can infect any other tissue.
1) Faculative intracellular growth - inhaled bacteria are gobbled up by neutrophils & macrophages but are not destroyed. Move to distant sites & set up camp. 2) Cell mediated immunity - Some macrophages succeed in destroying bacteria & present to T cells. T cells attract new macrophages to lungs causing destruction & caseous necrosis that calcifies. Bacteria stays trapped but may spread during immunity depression. |
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PPD Skin test
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Purified protein derivative - additional exposure will result in type 4 hypersensitivity & localized swelling & redness.
Positive PPD is bigger than 10mm in diameter or 5mm for aids pts after 48 hrs. Means active, latent or cured of TB. |
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Organ systems involved in TB
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1) Pulmonary TB - Reactivation occurs in apical areas. Chronic low fever, night sweats, weight loss, bloody cough.
2) Pleural & pericardial infection 3) Lymph node infection - Scrofula, usually cervical nodes 4) Kidney - red & white cells in urine 5) Skeletal - destroying IV discs in thoracic & lumbar spine 6) Joints- arthritis if 1 major joint 7) CNS - subacute meningitis 8) Miliary TB - All over body kidneys, liver, lungs. |
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Diagnosis of TB
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1) PPD indicates past exposure
2) Chest X-ray to look for Ghon focus, Ghon complex, or scarring, or active 3) Sputum acid fast stain & culture |
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Mycobacterium Leprae characteristics, transmission, diseases
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Acid fast rod, Impossible to grow on media, & unclear why only some are affected.
- Grows better in cool temps like skin, eyes, nerves, testes but spares warm areas - Severity is dependent on host immune response - Transmitted via respiratory secretions of infected. 1) Lepromatous leprosy - severest form due to defective T cells. Leonine facies, saddlenose deformity. 2) Tuberculoid leprosy - Can mount cell mediated defense against bacteria. So less severe Diagnose or prognose with Lepromin PPD. |
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Mycoplasma characteristics, diseases, & diagnostics
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Tiniest free living organism capable of self reproduction. Smaller than large viruses & lack cell wall, thus Pleomorphic. But has many sterols for protection.
Lack of cell wall leads to ineffectiveness of PCN. Mycoplasma pneumoniae - causes self limited bronchitis & pneumonia. Walking pneumonia. Can develop erythema multiforme: severe skin reaction with erythematous vesicles over mouth, eyes skin. Diagnostics: Cold agglutinins IgM antibodies target "I" antigen modefied with infection so red cells agglutinate at 4 deg C. Complement fixation, septum culture, DNA probe, PCR. Ureaplasma Urealyticum - Part of normal flora but can cause UTI. |
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3 bacterial that cause UTI
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Chlamydia trachomatis, Nesseria gonorrhoeae, Ureaplasma urealyticum.
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Clinical manifestations of TB
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Primary TB - Transmitted via aerosolized respiratory secretions of adult with TB. Can be asymptomatic, where organisms are walled off & forms Ghon focus or Ghon complex if it involves calcified lymph nodes. Can be symptomatic in immunocompromised & cause caseous necrosis.
Secondary or reactivation TB - Temporary weakening of immune system can reactivate TB. 10% chance of secondary TB in lifetime, 10% chance per year for those with HIV. |
