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Atypical Bacteria (5)
- Classification Criteria
- Types

Gram Stains are unreliable. aka "Gram Weird"
Types
- Mycobacteria
- Spirochetes
- Rickettisae spp.
- Chlamydiae + Chlamydophila
- Mycoplasma
Mycobacteria (Genus)
- Classification
- Common Types
- Misc Info.
- "Atypical" Bacteria
- aerobic, non-motile, rods (wiki)
- Mycobacterium tuberculosis + mycobacterium leprae
- Acid Fast Stain
- Special Cell Envelope - "waxy layer" -> allows transmission through air, resists desiccation + phagocytosis.
Spirochetes (Phylum)
- Classification
- Common Types
- "Atypical" Bacteria
- anaerobic + spiral shaped (wiki)
- Borrelia burgdorferi - Lyme Disease
- Treponema pallidum - Syphilis
- Dark Field Microscopy to visualize
Rickettisae spp. (Genus)
- Classification
- Common Types
- Misc Info
- "Atypical" Bacteria - Gram Negative
- Obligate intracellular bacteria (vector borne)
- Highly polymorphic (cocci, rods, thread-like) - (wiki)
- R. rickettsi - Rocky mountain spotted fever (misnomer)
- Wood + Dog Tick
- R typhi - endemic typhi
Symptoms - nausea, fever, muscle pain, rash
- Pathogenesis: Host Actin to move from 1 cell to another.
- Rash: Small pools of blood from ruptured capillaries
- Clinical + Exposure History
- Weil-Felix : Proteus Vulgaris (Test)
-
Chlamydiae + Chlamydophila
- Classification
- Common Types
- Misc Info
- "Atypical" Bacteria
- Obligate intracellular bacteria. "Energy Parasites"
- Chlamydiae trachomatis - blindness, nongonococcal urethritis, pneumoniae
- Chlamydophila psittaci - psittacosis (form on pneumonia)
- Chlamydophila pneumoniae - pneumonia
- Two membranes w/o peptidoglycan.
- Too small for Gram Staining.
Mycoplasma spp.
- Classification
- Types
- Misc Info
- "Atypical" Bacteria
- Mycoplasma Pneumoniae - "atypical" pneumonia
- lack cell wall
- sterols in plasma membranes
- very small
Anaerobic Bacteria
Gram + (3)
Gram - (2)
Gram +
- Sporeforming Rods: Clostridium,
- Non-sporeforming rods:Actinomyces
- Cocci: Peptococcus, Peptostreptococcus

Gram -
- Nonsporeforming rods: Bacteroides-like group, Fusobacterium
- Cocci - Veillonella
Bacteroides-like Bacteria
- groups (3)

- characteristics
- misc facts

- Gram (-), Anaerobic
- Part of "normal" flora in colon, mouth, vagina
Bacteroides
- LPS not endotoxic
- fragilis - capsule = antiphagocytic. makes enterotoxin. causes peritonitis -> abscess 


Porphyromonas
- pigmented, bile sensitive
- LPS is endotoxic
- bivia - female genital tract -> pelvic inflammatory disease + infertility
- melanginogenica - mouth. RTI

Prevotella
- pigmented, bile sensitive
- LPS is endotoxic
- gingivalis - mouth. RTI.
Clostridia

- characteristics
- types
- misc facts
- anaerobic (low tissue redox), gram (+) rods, spore forming rods

- part of normal GI flora + soil

- perfringens (90% of infections, 3rd food poisoning)
- septicum (cancer of GI)

- a toxin - lecithinase (PLC) - disrupts membranes

Wound Infections
- gas gangrene (clostridial myonecrosis)
- anaerobic cellulitis
- wound infections (least serious)
Organ Infections
- uterine (illegal abortions)
Bacterial Endospores
- types of Bacteria (2)
- resistance mechanism
- transmission
- Bacillus + Clostridium

- low H2O and high DNA stabilization

Diseases
anthrax (bacillus anthracis)
tetanus (clostridium tetani)
infections (histotoxic clostridia)
clostridium dificil
Campylobacter Jejuni
- Case Study = Chicken Sandwich
- curved/gull-winged, gram (-) rod, 42oC, microaerophilic
- LPS, adhesins,
- toxins (not important for disease)
- Cramps + Diarrhea (Bloody)
- Guillain-Barre syndrome - autoimmune, demyelinating neuropathy
- Ingestion, Animal Resevoir
Chlamydia Life Cycle
- Elementary Body (Spore-like) - Extracellular, disulfide bonds
- Endosome (prevent lysosome fusion)
- Reticulate body - divide + multiply
- Inclusion - endosome w/ reticulate bodies
Chlamydia Trachomatis
- gram negative, obligate intracellular parasite, small, no peptidoglycan
- serotypes cause distinct clinical disease
- replication in macrophages (lymph nodes)
- inflammation -> tissue dmg
-
Chlamydia Clinical Manifestations
- Urethritis (dysuria + urethral discharge)
- Reiter's dsyndrome - nongonococcal, acute aseptic arthritis (males)
- Pelvic Inflammatory Disease (PID)- lower abdominal pain, infertility + ectopic pregnancy
- Lymphogranuloma Venerum (LGV) - inflammation of lymphnodes that rupture (elephantiasis)
-
Chalmydia Diagnosis + Treatment
- PCR. Culture. Antibodies (serology)
- extended microbial therapy. Azithromycin
Chalmydia Congenital Problems
- Conjunctivitis - opthalmia neonatorum. ocular discharge, swollen eyelids, conjunctivae infected
- Pneumonia - afebrile (non-fever). nasal obstruction + staccato cough. tachypnea + rales w/o wheezing.
- systemic therapy!
Syphilis
- Spirochete. Treponema pallidum.
- lacks LPS
- GAGs (glycosaminoglycans) - extra outer membrane. molecular mimcry
- dark field microscapy
Treponema Pallidum Pathogenesis + Epidemiology
- minor abrasions + transplacentally
- endothelial cells
- MSM, poverty, crack cocaine, HIV, minorities
Treponema Pallidum Clinical manifestations
Primary Syphilis - hard painless ulcer. (women w/in cervix) + local lymph node enlargement
Secondary - dissemination -> skin, liver, joints, lymph, muscles + brain. Palms + soles + generalized lymphadenopathy.
Latent - resides within lymph. 3-30 years. asymptomatic. Treat during EARLY latency.
Tertiary - reactivates. Gumma (skin lesions), neurosyphilis (tabes dorsalis), cardiovascular lesions
Congenital Syphilis
- still birth (premature), physical deformity, neuro complications
- hepato + splenomegaly
- bone + teeth malformation. skin rashes.
Syphilis Diagnosis + Treatment
Clinical
- chancre, dark field microscopy, serology
Non-treponemal tests
- VDRL, RPR - IgM and IgG antibodies for lipids + lecithin
Treponemal tests
- FTA + MHA-TP
- + for life.
- Penicillin
Borrelia burgdorferi
- spirochete (endoflagella), dark field microscopy
- gram -
- Lyme Disease
- Tick Vector (Nymph) - 48 hrs of feeding
- Virulence: Osps: antigenic variability, adhesins (influence tissue/species tropism)
- Early: Bull's Eye rash w/ fever, malaise, fatigue, headache, chills
- Early Disseminated: Facial Droop (nerves) + cadiac dysfunction
- Late: Oligoarthitis, derm syndrome
- Case history + Clinical Symptoms
- Serological Testing (early diagnosis problem)
-
Bacillus Anthracis
- spore-forming, gram + rod
- 22 cases. 11 Inhalation.
- cutaneous (painless lesion)
- Inhalation - high mortality
- culture. nasal swab. PCR
- no person-to-person transmission
- AVA (vaccine)
- Polypeptide Capsule (instead of sugar)
Anthrax Toxin
- Exotoxin
- Lethal Toxin (kill macrophages, endothelial cells, neutrophils)
- Edema Toxin (cAMP -> tissue edema)
- Protective Antigen
-
Tularemia
- Francisella tularensis
- Gram Negative coccobacillus
- Facultative Intracellular pathogen
- Summer - Ticks
- Local infection w/ GI
- blood strem -> lymphatics
- ulceroglandular (Ulcer + lymph)
- Lung (aerosolized / weapon) - severe respiratory illness w/ unusual epidemiologic factors.
- sputum culture + antibodies
Yersinia Pestis
- Plague
- Gram - Rod
- Plague + fea bites
- Febrile lymphadenitis, pneumonia, septicemic.
- bloody sputum
- LPS, temp-dep enzymes
- VERY contagious
Haemophilus Influenzae
- amish boy w/ lethargy + stiff neck w/o immunization
- gram negative coccobacilli
- factor X + V (w/in blood cells)
- chocolate agar NOT blood agar
- capsule B
- Respiratory (droplets)
- day care setting
Haemophilus Influenzae
- Pediatric
- Adult
Pediatric
- Otitis Media, Meningitis (w/ hearing loss), Pneumonia (80%)

Adult
- nontypable strains = disease
- chronic bronchitis + pneumonia (COPD)
Haemonphilus Influenzae Virulence
- Capsule = immune evasion
- Polyribose ribosyl phosphate (type B)
- Endotoxin (LOS) - adhere to respiratory tract, IgA Protease, Pili

- culture = chocolate +, blood -
- Type B serotyping.
Therapy
- B lactams or Rifampin
Prevention
Incidence in children < 2yrs, but vaccine no good.
Mycoplasma Pneumoniae
- prokaryote w/o cell wall (NO B Lactams) + very small
- persistant cough (weeks) + rash
- Respiratory Epithelium ONLY (no alveoli) - w/ adhesins
- Dmg from peroxides + auto-inflammation

- Serology, PCR, Cold agglutinate (antibody presence)
- NO culture

Ribosome: tetracycline + macrolides or DNA: fluoroquinolones
Treatment helps symptoms not shedding.
Enterobacteriaceae General Characteristics
- Gram negative Rods
- Oxidase-negative (no cytochrome oxidase)
- MacConkey = pH color change (lactose for E. Coli, not Salmonella or Shigella)
-
E. Coli
Antigens - O (LPS), H (Flagella), K (Capsule)
- Human Resevoir. Normal Flora
- Virulence: Pili (type 1 and CFA - specific strains), Iron (siderophores), Toxins (LPS, Hemolysin, Heat-stable, Heat-labile, Shiga)
- UTIs (Community >>> Nosocomial), cystitis + pyelonephritis
- Neonatal Meningitis (K1 antigen)
Heat Stable Toxin
Heat Labile Toxin
Shiga Toxin

Heat Stable (STa) - cysteine rich (19 AAs)
- increase cGMP (electrolyte + fluid secretion)
Heat Labile (LT)
- like cholera toxin (1A and 5B), cAMP
Shiga Toxin (STX)
- inactivates ribosomes, stops protein synthesis
ETEC
- Enterotoxic
- CFA (plasmid encoded)
- watery diarrhea
- stays on microvillus surface
- produce LT or STa
EPEC
- bfp - bundle forming pilus
- type 3 secretion system: attachment creates a pedestal + delivery into enterocyte of TIR (the intimin receptor).
- Intimin - binding to TIR = tighter binding
EAEC
- diarrhea HIV+
- increase mucus secretion + biofilm
EIEC
- like shigella
- INVADES enterocytes (lyses vesicles)
- no specific pili
- type III secretion
- diarrhea w/ blood + leukocytes
EHEC/STEC
- shigatoxin: blood stool w/o fever
- hemolytic uremic syndrome - acute renal failure
- Jack-in-the-Box - undercooked meat
- like ETEC w/ production of shigatoxin (intimin, TIR)
-
Helicobacter pylori
- curved, gram negative rod
- stomach survival (virulence) urease + = raises local pH, flagella = move to mucus layer (higher pH)
- developing countries
- Disease = VacA - dmg epithelial cells, CagA - induce inflammation (pathogenicity island = type IV secretion system)
- gastritis, 1% gastric ulcers, gastric lymphoma
- biopsy, endoscopy (look for malignancy), breath test for urease
Clostridium Dificile
- Gram +, Rod, anaerobic, spore forming, toxin producing
- Nosocomial: Diarrhea (caused by antibiotic use)
- Toxin A (actin cytoskeleton interference, leaky and neutrophil chemotaxis) + Toxin B (actin, chemotaxis, and cytopathic effect)
- Diarrhea -> toxic megacolon
- stool = elevated leukocytes, sigmoidoscopy = pseudomembranes
Enterococcus (VRE)
- Gram + Coccus
- facultative anaerobe
- Nosocomial Infection  
- faecalis + faecium
- lower GI, UTI, bacteremia (lines + catheters)
- vancomycin resistance
- linezolid + daptomycin
Staph Aureus
- Gram +, Coagulase + (Staph epi = coagulase -)
- MRSA + Vancomycin resistance
- Nosocomial Infection
Klebsiella
- gram negative, aerobic or anaerobic
- Nosocomial Infection: Hand contact (10-15 minutes)
- mucoid: resist phagocytosis
- bacteremia, pneumonia, UTI
- B-lactamases (no penicillins), ESBL
- Carebepenems or aminoglycosides
Yersinia Enterocolitica
- gram - rods, contaminated food/water, extracellular growth
- GI; fever cramps, diarrhea
- YOPS - yersinia outer proteins, 
- Zipper entry through M Cells w/in Peyer's patch(invasin protein: produced before ingestion @ low temp) - multiple adherence proteins
Shigella Characteristics
- Enterobacteriacae
- Gram - rod
- Invasive Pathogen
- H2S negative, Lactose Negative
- Type III Secretion system
- Ipa (expressed after ingestion) -> Membrane Ruffling (macropinocytosis and cytoskeleton rearrangement)
- plasma-encoded genes
- Cytoplasma localization
- stops @ epithelium
Salmonella
- Enterobacteriacae
- Gram - rod
- Invasive Pathogen
- H2S Positive, Lactose Negative
- Type III Secretion -> Sip -> Membrane Rufling
- chromosomal encoded genes
- endosome localization
- nontyphoid - stops @ subepithelium
- typhoid - disseminates
Shigella Specifics (sonnei)
- low volume blood diarrhea/dysentery
- hijack cellular machinery (non-motile)
- extremely virulent, fecal-oral
Extracellular
- LPS
- Ipa (complex on M Cell) Mxi-Spa (Type III),
Cytoplasm
- IcsA+B (actin polymerization + enter other epithelial cells)
- Shiga toxin
Treatment: vaccine, fluids
Diagnosis: fecal leukocytes, culture
N. Gonorrhoeae
- Phase Variation
- Gram - diplo, oxidase + , thayer martin
- urethritis, PID
- NO capsule, NO maltose acid
- Pili, OPA (adhesins), LOS
- Recombination (pilin): PilE = expression, PilS = variable regions. PilS-> PilE = variation.
- Transformation (take up DNA)
- Phase variation: turn off pili gene
N. Meningitis Characteristics
- gram negative, oxidase + , nonmotile, diplo
- capsule (thick carb - looks like human sugars)
- pili, OPA (surface adhesins)
- acid (maltose)
- thayer martin
N. Meningitis Disease
- human disease (oung adults)
- meningitis belt in Africa
- Capsule - looks like human sugars (disease-causing)
- IgA Protease - cleaves hinge of Fab
- Siderophores (iron)
- LOS (inflammatory)

- Mucosal epithelium (pharynx) + forms plaques
- invade epithelium (multiply) -> brain + skin (purpura)
- MAC Def. -> Mengiococcal
- STIFF NECK + FEVER
- OXIDASE POSITIVE
- Penicillin or cephalosporin
- Vaccine (diptheria toxoid- MCV4 - all children)
- none for serotype B (big problem)
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