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Normal biota S. pyogenes, H. influenzae, S. pneumoniae, N. meningitidis, S. aureus, Moraxella, nonhemolytic and alpha hemolytic streptococci, Corynebacterium, Candida albicans Sinusitis Inflammation in sinues, varierty of viruses and bacteria; nasal congestion, pressure, headache or toothache, facial swelling and tenderness, discharge; agents: S. pyogenes, S. aureus, H. influenzae Acute otitis media Pain in ear and loss of hearing, irritability, fussiness, difficulty sleeping, eating and/or hearing, rupture of eardrum, mastoiditis, meningitis, intracranial abscess; agents: S. pneumoniae, H. influenzae, Moraxella catarrhalis; not communicable Haemophilus spp. characteristics Wide variety of infections, G- coccobacilli, many possess capsules, require X factor and/or V factor, chocolate agar is medium H. influenzae pathogenesis Capsules, adherence factors = virulence factors; 90% nontypable strains adhere to buccal mucosa; Hib = more invasive; may be bloodstream invasion that promotes meningitis, epiglottitis or cellulitis H. influenzae clinical manifestations Otitis media, sinusitis, epiglottitis, bronchitis, pneumonia, cellulitis, conjunctivitis, meningitis H. influenzae epidemiology Unencapsulated strains in nasopharynx, droplet transmission, most cases of meningitis and cellulitis in kids 2 mo-4y.o.a. H. influenzae diagnosis Gram stain, isolation, biochemical ID, carriage rates high, fastidious, tests for PRP include latex agglutination and EIA Pharyngitis signs and symptoms Inflammation of throat, pain, swelling, reddened mucosa, swollen tonsils, white packets of inflammation on walls of throat Pharyngitis causative agents Cold viruses and S. pyogenes S. pyogenes strep throat complications Scarlet fever, rheumatc fever, acute glomerulonephritis C. diphtheriae characteristics G+, club-shaped C. diphtheriae pathogenesis Diphtheria toxin, A-B exotoxin, systemic effects include cardiac damage, depression of respiration and paralysis of soft palate C. diphteriae clinical manifestations Commonly a local infection, mucus membranes of pharynx affected, pseudomembrane formed, interfere w/ breathing, cutaneous infection, abrupt onset w/ fevere,, sore throat, enlarged cervical lymph nodes, bullneck appearance, cardiac and circulatory dysfunctions, paralysis of soft palate; non-toxigenic strains: endocarditis, arthritis, recurrent soft throat C. diphtheriae epidemiology Maintained in humans, endemic and epidemic in nautre, P2P via droplets C. diphtheriae diagnosis Pseudomembrane clinical specimen, gram stain, isolation, biochemical tests, Elek test B. pertussis morphology and physiology Small E- coccobacilli, obligate aerobes, media supplemented w/ charcoal or other supplements B. pertussis virulence factors Filamentous hemagglutinin, pertussis toxin, tracheal cytotoxin, endotoxin B. pertussis clinical manifestations Catarrhal stage: replication, mild URI symptoms; paroxysmal stage: ciliated epithelial cells extruded, clearance of mucus impaired, violent, spasmodic productive cough w/ whoop, vomiting; convalescence stage: cough may persist; complication: bronchitis, pneumonia B. pertussis epidemiology Humans = reservoir; survive a few days outside body, transmitted via contaminated object, direct contact, droplet inhalation; highest transmission during catarrhal stage, highly communicable B. pertussis diagnosis Gold standard = culture of nasopharyngeal secretions; fastidious; clinical diagnosis used, PCR-based assays, ELISA for fimbrial hemagglutinin used for epidemiology M. tuberculosis morphology Acid-fast positive, slender, slightly curved rods M. tuberculosis chemical composition Polypeptides are outer layer (Ag, PPD), lipids = mycolic acid -> acid fastness M. tuberculosis physiology Cord factor causes bacterium to grow in filaments, obligate aerobes, require complex media, long generation time M. tuberculosis pathogenes, signs and symptoms Easily infected but resist disease; primary TB: depends on route of entry, bacteria grow in unactivated alveolar macrophages, T cells and macrophages wall off area w/ fibrin (tubercle), tubercles can break into necrotic caseous lesions that heal by calcification; secondary TB:tubercles expand and drain into bronchial tubes and URT, symptoms include violent coughing, greenish/bloody sputum, low grade fever, anorexia, weight loss, extreme fatigue, night sweats and chest pain; extrapulmonary TB: common targets are lymph nodes, kidneys, long bones, genital tract, brain and meninges M. tuberculosis epidemiology Most prevalent in underdeveloped countrys, airborne transmission, low infectious dose, humans only important source of transmission but not only carriers M. tuberculosis diagnosis Tuberculin testing, chest X0ray, direct ID of AFB, isolation and culture and antibiogram, PCR, nucleic acid probes M. avium complex characteristics Clinical illnesses in individuals w/ damaged tissues, no P2P transmission MAC clinical manifestation TB-like disease, disseminated in AIDS patients MAC epidemiology Ubiquitous in water and soil environments, transmission by infectious aerosol/ingestion MAC diagnosis Isolation, culture and biochemical tests Pneumonia signs and symptoms URT symptoms (runny noe, congestion, headache, fever, and/or GI symptoms), lung symptoms (chest pain, fever, cough, discolored sputum, dyspnea) Community-acquired pneumonia bacterial agents S. pneumoniae, L. pneumophila, M. pneumoniae, C. pneumoniae S. pneumoniae - pneumonia Risk factors: old age, season, underlying disease; lobar pneumonia, consoldiation L. pneumophila characteristics Poorly staining G- pleomorph, obligate aerobe, fastidious nutritional requirements, charcoal yeast-extract medium, slow growers L. pneumophila clinical manifestaton Legioneloosis (headache, malaise, myalgia, dramatic temp rise, nonproductive cough, vomiitng, diarrhea, abdominal pain, bronchopneumonia; pontiac fever (less sever, fever, headache, myalgia, dry cough, self-limitng) L. pneumophila epidemiology Worldwide, sporadic, parasitizes amoebae, in biofilms; risk factors = exposure to epidemic source, age > 50 y.o.a., smokers, people w/ compromised CMI; airoborn transmission L. pneumophila diagnosis ELISA M. pneumoniae characteristics Smallest and simplest of bacteria, smallest genome, single triple-layered membrane M. pneumoniae pathogenesis and clinical manifestation Mycoplasma pneumonia, adhere specifically to respiratory epithelial cells by adhesin, interfere w/ ciliary action, impair normal clearance, incubation: 9-21 days, insidious onset, can be URI, bronchopneumonia w/ lack of lobar consolidation, course varies w/ remittent fever, cough, headache, elevated WBC, positive cold agglutinins test M. pneumoniae epidemiology 20% pneumonia cases, infectious droplet transmission, low infectious dose M. pneumoniae diagnosis Culture, isolation, biochemical tests, ELISA, cold agglutinins test, DNA probe test, NAATS Chlamydiaceae characteristics Chlamydia and Chlamydophila; very small G- like cocci, small genome; obligate intracellular parasite, 3 phases; can't make ATP C. pneumoniae clinical manifestation Acute respiratory tract infections (sinusitis, bronchitis, pneumonia), correlated w/ atherosclerosis C. pneumoniae epidemiology P2P transmission, respiratory droplet, incubation: 7-21 days; coinfection w/ viurses common, reinfections common, serum Ab not protective C. pneumoniae diagnosis NAATS, MIF Bacterial agents of hospital acquired pneumonia S. pneumoniae, Klebsiella spp., Enterobacter spp., E. coli, P. aeruginosa, S. maltophila, Acinetobacter spp. K. pneumoniae characteristics G-, aerobic bacilli; major virulence factor = capsule; resistant to many antibiotics becasue of R plasmid K. pneumoniae clinical manifestation Pneumonia, UTI, community acquired pneumonia = Friedlander's disease; nosocomial acquired infections include sepsis, meningitis, surgical wound infections K. pneumoniae diagnosis Gram stain, isolation and culture, biochemical tests, antibiogram Pseudomonas characteristics Large G- rods, single polar flagellum or 2-3 flagella, capsule-like envelope or slime layer, green, blue-green and fluorescent P. aeruginosa physiology and metabolism Use many compounds for growth, wide temperature range, survive in many environments, produces pigments, resistant to high concentrations of salt, dyes, disinfectants, antibiotics P. aeruginosa pathogenesis and clinical manifestations Biofilm development, virulence factors (capsular polysaccharide, fimbriae and LPS), antibiotic resistance, when protective coating of mucosa gone, can be infected, can nfect CF patients, burn and leukemia patients, bacteremia P. aeruginosa epidemiology Ubiquitous, P2P transmission, nosocomial infections P. aeruginosa diagnosis Isolation, gram stain, blue-green pigment, fluorescence, fruit-like odor S. maltophilia characteristics Nosocomial pathogen, resistant to many broad-spectrum antibiotics S. maltophilia pathogenesis Nosocomial infections may be affected by ability to adhere to plastic, glas and teflon and survive and multiply in various types of IV infusates S. maltophilia clinical manifestations Bacteremia, endocarditis, respiratory tract infection, CNS infection, ophthalmologic infection, UTI, skin/soft tissue infection, bone and joint infection, GI infection S. maltophilia epidemiology In soil and water, food, nosocomial sources