Bacteria(Once & For All)

S. aureus

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive cocci in clusters

• Facultative anaerobe

• Catalase positive(separates it from catalase negative streptococci) and coagulase positive(it is the only staphylococci that does this)

• Protein A(Binds Fc portion of IgG antibodies and prevents opsonization and phagocytosis), TSST-1(Causes toxic shock syndrome), enterotoxins

• Abscesses pus/cutaneous issues but also many other effects(Impetigo, furuncles/carbuncules/cellulitis, osteomyletitis, endocarditis, scalded skin syndrome, toxic shock syndrome, food poisoning)

• MSSA: [1st choice: Cloxacillin, dicloxacillin, cefazolin, cephalexin][2nd choice: Macrolides and clindamycin(to inhibit toxins)], MRSA: [1st choice: Vancomycin][2nd choice: Daptomycin, Linezolid][Last line: Ceftaroline,Tigecycline]

S, pyogenes

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive cocci in chains

• Facultative anaerobe

• Catalase negative(It’s not staph), beta-hemolytic(It’s group A strep, same result as group B strep), Bacitracin sensitive(Group B is not), PYR positive

• M protein(inhibits complement system and causes rheumatic fever due to antibodies trying to kill M protein), adhesins(Lipoteichoic acid and protein F)

• Pyogenic(Strep-throat, erysipelas), Toxigenic(Scarlet fever, necrotizing fasciitis)

• [1st choice: Amoxicillin, PGS, cefazolin, cephalexin][2nd choice: Macrolides, clindamycin(For toxin damage)]

S. agalactiae

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive cocci in chains

• Facultative anaerobe

• Catalase negative(Because it’s a strep.), beta hemolysis(because it’s group B), Bacitracin negative(Unlike pyogenes!)

• Polysaccharide capsule(Prevents complement activation)

• Sepsis, pneumonia, neonatal meningitis

• [1st choice: Amoxicillin and PGS(IV)][2nd choice: Cefazolin, cephalexin][3rd choice: Vancomycin, clindamycin]

S. pneumoniae

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive diplococci with lancet shape

• Facultative anaerobe

• Catalase neg(It’s a strep.), alpha hemolysis, optochin positive(Gold standard to distinguish from viridans)

• Polysaccharide capsule and IgA protease

• Meningitis, otisis media, pneumonia, sinusitis(MOPS, the #1 cause for all of these)

• [1st choice: Amoxicillin, PGS, Ceftriaxone, Cefotaxime, Azithromycin][2nd choice: Cefuroxime][3rd choice: levofloxacin, moxifloxacin, vancomycin]

S. viridans

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive cocci

• Facultative anaerobe

• Catalase negative(Strep.), alpha hemolytic(like pneumoniae), optochin negative(Resistant to it unlike pneumoniae), Bile insolube

• Biofilm

• Dental caries(S. mutans), endocarditis

• [1st choice: Amoxicillin, PGS][2nd choice: 3rd gen ceph.][Last: Vancomycin]

S. suis

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive cocci

• Facultative anaerobe

• Catalase neg, alpha hemolysis(Like pneumo and viridans), optochin neg.

• Polysaccharide capsule(Like pneumo and agalactiae)

• Meningitis and hearing loss

• [1st choice: Amoxicillin, PGS][2nd choice: 3rd gen ceph.][Last: Vancomycin]

Enterococcus faecalis

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive cocci

• Facultative anaerobe

• Catalase negative, gamma hemolytic, survives 6.5 NaCl and bile

• Enzymes, capsule, adhesins

• UTIs(patient w foley catheter)

• [In order: Amoxicillin, vancomycin, linezolid]

Enterococcus faecium

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive cocci

• Facultative anaerobe

• Catalase negative, gamma hemolytic, survives 6.5 NaCl and bile

• Enzymes, capsule, adhesins

• UTIs(patient w foley catheter)

• [In order: Vancomycin, linezolid, tigecycline]

Gram positive cocci are all…

Facultative anaerobes

B. anthracis

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive rods in chain with endospores

• Strict aerobe

• Catalase positive

• Anthrax toxin, protein capsule, endospores

• Cutaneous, gastrointestinal, and inhalation anthrax(The last one is the worst)

• [Ciprofloxacin, clindamycin]

B. cereus

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive rods with endospore

• Facultative anaerobe

• Catalase positive but motile unlike anthracis

• Enterotoxins and endospore

• Food poisoning sometimes w diarrhea or vomitting

C. tetani

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive rod

• Strict anaerobe

• Nothing important

• Tetanospasmin(Acts on GABA), endospore

• Lockjaw, arched back

• Anti-toxin

C. botulinum

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Anti-toxin

• Gram positive

• Strict anaerobe

• Nothing important

• Botulinum toxin(Acts on SNARE at the NMJ)

• Symmetric, descending flaccid paralysis

C. perfringens

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive rod

• Anaerobic aerotolerant

• Nothing important

• Alpha toxin(Causes muscle death) and endospore

• Food poisoning or gas gangrene(due to spores)

• PGS +- clindamycin

C. difficile

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive rod

• Strict anaerobe

• Nothing important

• Toxin A(destroys brush border) and toxin B(Forms the pseudomembrane), will attack in dysbiosis

• Pseudomembranous colitis

• Vancomycin(ORAL), fidaxomicin, metronidazole

C. diphtheriae

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive rods that look like “Chinese letters” and are actinobacterium that are mod. AFB and AFB negative

• Facultative anaerobe

• Nothing important

• A-B toxin(“B binds”, A kills)

• Pseudomembrane that bleeds at the pharynx/tonsils, bull neck, and toxins traveling to heart and nerves

• Anti-toxin + Erythromycin

L. monocytogenes

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive, small rods

• Facultative anaerobe that grows at fridge temp

• None, it’s motile though

• Phospholipase C(Vacuole escape)

• Neonatal meningitis and in elderly

• Ampicillin +- gentamicin

C. acnes

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive small rods but are actually actinobacterium but both AFB and mod. AFB negative

• Aerotolerant anaerobe

• None

• None, it attacks the sebaceous glands and sticks well to prosthetics

• Acne

• Doxycycline, clindamycin

M. tuberculosis

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive but very poorly but is an actinobacterium that’s AFB positive.

• Strict aerobe

• None

• Mycolic acid and cord factor

• Flu symptoms until reactivation when they break out of Ghon complexes, causing fever, night sweats, weight loss, bloody cough

• 4HRZE 2HR + vitamin B6

M. leprae

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive but not visible rods, but are actinobacterium that are AFB positive

• Strict aerobic

• NON-CULTURABLE

• Mycolic acid and cord factor

• Tuberculoid leprosy: numb skin patches, Lepromatous leprosy: thickened skin, loss of eyebrows, loss of sensation

• Dapsone, rifampicin, clofazimine

N. asteroides

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive rods that are modified AFB positive, branching filamentous

• Strict aerobe

• None

• Mycolic acid defense

• Lung abscess, brain abscess, skin abscess, mycetoma, dyspnea

• Trimethoprim-sulfamethoxazole

A. israeli

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive branching filamentous rod, both mod.AFB and AFB negative

• Strict anaerobe

• Finding yellow granules

• Lumpy jaw after dental trauma, forming swelling and sinus tracts with sulfur granules

• PGS

G. vaginalis

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram variable coccobacilli, both mod. and full AFB negative

• Facultative anaerobe

• Clue cells in vaginal smear

• Nothing

• Attacks in dysbiosis, fishy odor with discharge

• Metronidazole

R. equi

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram positive coccobacilli that’s slightly mod. AFB positive

• Strict aerobe

• None

• None

• Pulmonary abscess, productive cough, fever and weight loss

• Rifampin + macrolides or vancomycin

Neisseria meningitidis

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative diplococci

• Strict aerobe

• Chocolate agar

• Polysaccharide capsule to avoid phagocytosis, pilli for adhering to the nasopharynx, IgA protease

• Meningitis, meningococcemia(including purpura, Waterhouse Frederichsen syndrome)

• Ceftriaxone

Neisseria gonorrhoeae

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative diplococci

• Strict aerobe

• None

• Pilli to attach to mucosa, IgA protease, LOS of course bc it’s gram neg.

• Dysuria with pus-like discharge in men, cervicitis and PID in women, ophtalmia neonatorum in neonates, ITS AN STI

• Ceftriaxone, PGS

Moraxella catharrhalis

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative diplococci

• Strict aerobe

• None

• Nothing important

• Otitis media(3rd highest behind S. pneumo and H. influenzae), acute sinusitis, COPD exasberation

• Amox-clav, 2-3rd gen cephalosporin, macrolides

Escherichia coli

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative bacilli

• Facultative anaerobe

• Oxidase negative, lactose positive

• Fimbriae to bind, K protein in ones that cause neonatal meningitis, T3SS that can cause sepsis

• Gastrointestinal, UTIs, Neonatal meningitis(2nd behind S. agalactiae), sepsis

• Fosfomycin, nitrofurantoin, amox-clav, ampi-sul, cephalosporins/FQ, aminoglycosides

  • ESBL: Carbapenems, colistin

  • CRE: Mero-vaborbactam, ceftaz-avibactam, colistin

K. pneumoniae

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative rods

• Facultative anaerobe

• Oxidase negative, lactose fermenter

• Thick capsule, thicker than S. pneumoniae, larger size than E. coli

• Pneumonia with currant jelly sputum, liver abscesses, UTIs in patients who used catheters

• Fosfomycin, nitrofurantoin, amox-clav, ampi-sul, cephalosporins/FQ, aminoglycosides

  • ESBL: Carbapenems, colistin

  • CRE: Mero-vaborbactam, ceftaz-avibactam, colistin

Salmonella typhi

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative bacilli

• Facultative anaerobe

• Oxidase negative, non-lactose fermenter

• Nth important

• Step fever, rose spots, green pea diarrhea, bradycardia

• Ceftriaxone, ciprofloxacin, azithromycin

Shigella spp.

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative rods

• Facultative anaerobe

• Oxidase negative, lactose non-fermenter

• Shiga toxin

• Blood stool, tenesmus, bacillary dysentry

• Ciprofloxacin, ceftriaxone, azithromycin

Pseudomonas aeruginosa

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative coccobacilli

• Strict aerobes

• Oxidase positive, non-fermenter of lactose

• Nothing important

• BE PSEUDO, it’s opportunistic

• Ceftazidime, cefoperazone-sulbactam, cefepime, piperacillin-tazobactam, carbapenems except ertapenem, aminoglycosides, ciprofloxacin, levo/moxifloxacin

  • If CRPA: Colistin

Acinetobacter baumannii

• Gram staining and shape and any extra microscope morphology if needed

• Oxygen metabolism

• Key laboratory tests

• Virulence factors

• Symptoms

• Drugs of choice

• Gram negative coccobacilli

• Strict aerobe

• Oxidase negative, lactose negative

• Nothing important

• Found in IV/catheter patients and can cause septicemia, foley patients and cause UTI, it’s opportunistic

• Carbapenems except ertapenem

  • CRAB: Colistin

Burkholderia pseudomallei

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Transmission:

• Drugs of Choice:

• Gram-negative rod; "Safety-pin" (bipolar) staining.

• Facultative anaerobe.

• Oxidase positive; lactose non-fermenter

• Nth important

• Found in mud/stagnant water (SE Asia); associated with monsoons/heavy rain. Causes Pneumonia (mimics TB) and skin abscesses. High risk in Diabetics.

• Ceftazidime or Imi/Meropenem (Intensive phase); TMP-SMX (Eradication phase).

Legionella pneumophila

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Gram staining/shape: Gram-negative rod (stains poorly, use silver stain).

• Oxygen metabolism: Facultative anaerobe/intracellular

• Lab tests: Nth

• Virulence factors: Nth

• Symptoms/Key transmission facts: AC units/water towers; Pneumonia + Diarrhea + Hyponatremia (low sodium) OR pontiac fever, a mild-flu like illness

• Drugs of Choice: Azithromycin or Moxi/Levofloxacin

Haemophilus influenzae

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

Haemophilus influenzae

• Gram staining/shape: Gram-negative coccobacillus (pleomorphic).

• Oxygen metabolism: Facultative anaerobe.

• Lab tests: Chocolate agar (needs Factor V and X)

• Virulence factors: Capsule; IgA1 protease.

• Symptoms/Key transmission facts: Epiglottitis (thumbprint sign/drooling), Meningitis, Otitis media.

• Drugs of Choice: BL+: Amox-clav, Ampi-sul, Ceftriaxone. BL-: Amoxicillin, Ampicillin, Cefuroxime

Haemophilus ducreyi

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Gram staining/shape: Gram-negative coccobacillus; "School of fish" appearance.

• Oxygen metabolism: Facultative anaerobe.

• Lab tests: Hard to grow; requires GC agar with hemoglobin; diagnosis often clinical.

• Virulence factors: Cytolethal distending toxin (causes tissue necrosis).

• Symptoms/Key transmission facts: Chancroid = Painful genital ulcer + painful inguinal buboes (buboes may rupture). "Ducreyi makes you cry."

• Drugs of Choice: Azithromycin or Ceftriaxone.

Bordetella pertussis

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Gram staining/shape: Gram-negative coccobacillus.

• Oxygen metabolism: Strict aerobe.

• Lab tests: Nth

• Virulence factors: Pertussis toxin

• Symptoms/Key transmission facts: Whooping cough (inspiratory whoop); Post-tussive emesis; 100-day cough.

• Drugs of Choice: Macrolides (Azithromycin/Clarithromycin).

Vibrio cholerae

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Gram staining/shape: Gram-negative comma-shaped rod.

• Oxygen metabolism: Facultative anaerobe.

• Lab tests: Oxidase positive

• Virulence factors: Cholera toxin

• Symptoms/Key transmission facts: Rice-water stools (painless/watery); Extreme dehydration; Contaminated water.

• Drugs of Choice: Azithromycin, Ciprofloxacin, Doxycycline.

• Vibrio vulnificus:

• Vibrio parahaemolyticus:

• Cellulitis or necrotizing fasciitis in a patient who cut their leg in saltwater or developed septicemia after eating raw oysters (especially in patients with liver disease/hemochromatosis).

• Self-limiting watery diarrhea and abdominal cramps after eating contaminated seafood (sushi/oysters) in Japan or coastal areas.

Helicobacter pylori

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Gram staining/shape: Gram-negative curved/spiral rod.

• Oxygen metabolism: Facultative anaerobe.

• Lab tests: Strongly Urease positive

• Virulence factors: Urease (neutralizes acid)

• Symptoms/Key transmission facts: Gastritis; Duodenal/Gastric ulcers; MALT lymphoma risk.

• Drugs of Choice: Amoxicillin + Clarithromycin + PPI (± Metronidazole).

Campylobacter jejuni

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Gram staining/shape: Gram-negative S-shaped or "gull-wing" rod.

• Oxygen metabolism: Facultative anaerobe.

• Lab tests: Oxidase positive

• Virulence factors: LOS molecular mimicry (leads to GBS).

• Symptoms/Key transmission facts: Undercooked poultry; Bloody diarrhea; Mimics appendicitis; Associated with Guillain-Barré Syndrome.

• Drugs of Choice: Macrolides (Azithromycin or Clarithromycin).

Treponema pallidum

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

Treponema pallidum

• Gram staining/shape: Gram-negative structure but invisible on Gram stain; Spirochete (corkscrew).

• Oxygen metabolism: Facultative anaerobe.

• Lab tests: Dark-field microscopy

• Virulence factors:

• Symptoms/Key facts: Primary (painless chancre); Secondary (rash on palms/soles, condyloma lata); Tertiary (gummas, neurosyphilis), ITS AN STI

• Drugs of Choice: Benzathine Penicillin G (IM). (IV Penicillin G for Neurosyphilis).

Leptospira interrogans

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Gram staining/shape: Gram-negative structure; Spirochete with "question mark" hooks at the ends.

• Oxygen metabolism: Strict aerobe.

• Lab tests: Dark-field microscopy; MAT (Microscopic Agglutination Test) is the gold standard.

• Virulence factors: Flagellar motility (burrows into tissues); LPS (inflammation).

• Symptoms/Key transmission facts: Found in animal urine (rats/dogs); Water sports or farming. Phase 1: Flu-like illness with muscle pain conjunctival suffusion (red eyes without pus). Phase 2 (Weil Disease): Liver failure (jaundice) + Renal failure + Hemorrhage.

• Drugs of Choice: PGS (Penicillin G) for severe disease; Doxycycline or Ceftriaxone for mild cases/prophylaxis.

Orientia tsutsugamushi

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Morphology/Shape: Gram-negative (though stains poorly); small coccobacillus

• Oxygen metabolism: Obligate intracellular, facultative anaerobe.

• Lab tests: Nth

• Symptoms/Key transmission facts: Causes Scrub Typhus; Transmitted by the bite of larval mites (chiggers). Key finding: Eschar (a black, necrotic scab at the bite site) followed by fever, headache, and generalized lymphadenopathy. Found in the "Tsutsugamushi Triangle" (Asia-Pacific region).

• Drugs of Choice: Doxycycline, azithromycin

Rickettsia typhi

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Morphology/Shape: Gram-negative structure (stains poorly); small coccobacillus

• Oxygen metabolism: Obligate intracellular facultative anaerobe.

• Lab tests: Serology (IFA); Weil-Felix test (Positive for OX-19).

• Symptoms/Key transmission facts: Transmitted by the Rat flea (Xenopsylla cheopis). Symptoms include fever, headache, and a maculopapular rash that starts on the trunk and spreads outward to the extremities (centrifugal spread), usually sparing the palms and soles.

• Drugs of Choice: Doxycycline, azithromycin

Chlamydia trachomatis

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Morphology/Shape: Gram-negative structure (lacks peptidoglycan, so does not show on Gram stain)

• Oxygen metabolism: Obligate intracellular facultative anaerobe.

• Lab tests: Nth

• Symptoms/Key transmission facts: Most common bacterial STI. Causes non-gonococcal urethritis (clear/watery discharge) and PID in women.

• Drugs of Choice: Doxycycline (first line) or Azithromycin

Chlamydophila pneumoniae

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Morphology/Shape: Gram-negative structure

• Oxygen metabolism: Obligate intracellular facultative anaerobe.

• Lab tests: Nth

• Symptoms/Key transmission facts: Causes "Atypical" pneumonia. Presents with a gradual onset of non-productive cough, sore throat (pharyngitis), and low-grade fever. Unlike S. pneumoniae, the patient usually doesn't look very "sick" and can continue their daily activities. Common in school-aged children and young adults.

• Drugs of Choice: Azithromycin (preferred) or Doxycycline.

Chlamydophila psittaci

• Morphology/Shape:

• Oxygen metabolism:

• Lab tests:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Morphology/Shape: Gram-negative structure

• Oxygen metabolism: Obligate intracellular facultative anaerobe.

• Lab tests: Nth

• Symptoms/Key transmission facts: Psittacosis (Parrot Fever). Transmitted by inhaling dried bird feces or secretions (parrots, turkeys, pigeons). Causes atypical pneumonia, high fever, and often hepatosplenomegaly. A classic vignette clue is "Horder spots" (pink macules on the skin)

• Drugs of Choice: Doxycycline, then azithromycin

Mycoplasma pneumoniae

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Morphology/Shape: No cell wall (contains sterols in the membrane instead), so it does not Gram stain; Pleomorphic shape;

• Oxygen metabolism: Obligate paraiste

• Lab tests: Nth

• Symptoms/Key transmission facts: Walking pneumonia. Common in young adults in military barracks or dorms. Features a persistent non-productive cough, patchy X-ray that looks much worse than the patient feels, and occasionally Stevens-Johnson Syndrome or bullous myringitis (blisters on the eardrum).

• Drugs of Choice: Azithromycin (preferred) or Doxycycline.

Ureaplasma urealyticum

• Gram staining/shape:

• Oxygen metabolism:

• Lab tests:

• Virulence factors:

• Symptoms/Key transmission facts:

• Drugs of Choice:

• Morphology/Shape: No cell wall → No gram stain

• Oxygen metabolism: Facultative anaerobe (microaerophilic).

• Lab tests: Urease positive

• Symptoms/Key transmission facts: Often part of the normal vaginal flora but can cause non-gonococcal urethritis or cervicitis and PID in women

• Drugs of Choice: Azithromycin or Doxycycline.