Gram-Negative Bacteria and others

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1 Slide 1 Gram-Negative Bacteria and others Robert P. Rapp, Pharm. D. College of Pharmacy Slide 2 Gram-negative Bacteria - Respiratory Related Hemophilus influenzae Usually Community Acquired Gram-Negative rod (almost cocci like) (extracellular, aerobic) Exotoxins - none. Source - humans are the only resevoir Capsule - polysaccharide - enables strain b to resist phagocytosis. Slide 3 Gram-negative Rods Respiratory related Hemophilus influenzae (continued) Pneumonia - young children and the elderly Presdisposed by alcoholism, smoking, or COPD. Meningitis - No. 1 organism in children 6 mo - 6 years (almost always Strain or Type B) Eppiglottis - No. 1 cause in young children. Sinusitis and Otitis media. Purulent conjunctivitis. Slide 4 Gram-negative Bacteria - Respiratory related Klebsiella pneumonia Gram-negative rod (aerobic, extracellular) Can be either community acquired (alcoholism) or nosocomial Source - can be part of normal colon flora Capsule - polysaccharide - resist phagocytosis.

2 Slide 5 Gram-negative Bacteria - Respiratory Related Klebsiella pneumonia (continued) Pneumonia - bronchopneumonia and lobar Urinary tract - common cause but second to E. coli Bacteremia - Second to E. coli - as a cause of nosocomial blood stream infections. Slide 6 Gram-negative Bacteria - Respiratory Related Legionella pneumophila Gram-negative rod - aerobic, intracellular Nosocomial or community acquired Exotoxin - possibly - not well studied Source - Standing water (air-conditioning, spas, humidifyers) - inhalation of aerosols. Capsule - none Slide 7 Gram-negative Rod - Respiratory Related Legionella pneumophilia (Continued) Atypical pneumonia - can be fatal in the elderly and immunosuppressed individuals. Pontiac fever - usually resolves spontaneously in one week or so. Slide 8 Gram-negative Bacteria - Respiratory Related Pseusomonas aeruginosa Gram-negative rod - aerobic, extracellular (pigment formation - blue/green) Primarily nosocomial, but some community acquired. Exotoxin - many Exotoxin A, Hemolysins, Exoenzymes Source - Moist areas, sinks, whirlpools, swimming pools, spas, skin, mucus membranes Capsule - Exopolysaccharide

3 Slide 9 Gram-negative Bacteria - Respiratory Related Pseudomonas aeruginosa (continued) Pneumonia - necrotizing, bronchopneumonia in immunocomprimised, cystic fibrosis, rapidly fatal. Burn wound infection - necrosis of tissue, rapid development. Endocarditis - I.V. drug abuser Bacteremia - Septic shock, rapidly fatal. Corneal keratitis - contact lenses External otitis - swimmer s ear, often recurrent Slide 10 Gram-negative Bacteria - UTI Related Escherichia coli Uropathogenic, Enterotoxigenic, EnteroHemorrhagic (0157:H57), EnteroInvasive. Gram-negative rod, aerobic extracellular Exotoxins - several types of hemolysins Source - most common aerobic bacteria in the fecal flora, horizontal transmission. Capsule - Polysaccharide Slide 11 Gram-negative Bacteria - UTI Related Escherichia coli (continued) UTI - upper (pyelonephritis), and lower (cystitis). Most community acquired are uncomplicated and occur in women. Most nosocomial are complicated and associated with catheters, or urolithiasis. Bacteremia and sepsis - No 1 nosocomial cause - secondary to UTI or I.V. lines. Neonatal meningitis - Slide 12 Gram-negative Bacteria - UTI Related Escherichia coli EnteroToxigenic - mild or explosive diarrhea, so called traveler s disrrhea, Mexico, Asia, Africa. Contaminated food and water. EnteroPathogenic - diarrhea, nausea, vomiting, mostly in young children - day care, schools. EnteroHemorrhagic - Hemorrhagic colitis. Can cause hemolytic-uremic syndrome with acute renal failure, hemolytic anemia, thrombocytopenia - children and elderly. Most caused by 0157:H57 strains. Contaminated water, and uncooked hamburger.

4 Slide 13 Gram-negative Bacteria, UTI Related Proteus mirabilis Gram-negative rod, aerobic, extracellular, swarming - movement by flagella. Source - Normal colonic flora, horizontal transmission can occur. Most commonly community acquired but may be nosocomial Capsule - none. Slide 14 Gram-negative Bacteria, UTI Related Proteus mirabilis (continued) UTI - upper (pyelonephritis) and lower (cystitis) Urolithiasis - All Proteus spp, secrete urease, which splits urea to generate ammonia - alkaline urine, which enables precipitation of magnesium, ammonium phosphate. Slide 15 Gram-negative Bacteria - UTI Related Enterobacter cloacae Gram-negative rod, aerobic, extracellular Source - normal flora of gut, transmission is nosocomial - I.V. catheters, respiratory equipment, etc. Horizontal transmission occurs Capsule - probably not. Slide 16 Gram-negative Bacteria - UTI Related Enterobacter cloacae (continued) UTI - upper (pyelonephritis), lower (cystitis) Usually nosocomially acquired - opportunistic infections. Bacteremia - secondary to UTI, pneumonia, lines. Pneumonia - nosocomially acquired, opportunistic infections. Occurs particularly in patient on mechanical respiration.

5 Slide 17 Special Note for Pharmacists!! The following Gram-negative bacteria can grow in dextrose containing I.V. solutions. Klebsiella pneumonia Enterbacter spp. Serratia marcescens Virtually all intrinsic or extrinsic cases of contaminated I.V. fluids have been with these bacteria. Slide 18 Gram-negative Bacteria- UTI Related Serratia marcescens Gram-negative rod, aerobic, extracellular Source - normal flora of the gut, transmission is usually nosocomial, I.V. lines, respirators, horizontal transmission can occur. Capsule - no. Slide 19 Gram-negative Bacteria-UTI Related Seerratia marcescens (continued) UTI, upper (pyelonephritis), lower (cystitis) Bacteremia - usually secondary to UTI, pneumonia, I.V. lines, solutions. Endocarditis - I.V. drug users (heroin) - usually right sided. Infective arthritis - iatrogenic from intra-articular injections Slide 20 Helicobacter pylori Gram-negative rod (comma shaped), microaerophilic, extracellular, motility by flagella cork-screw movement., but produces urease that generates ammonium ion to buffer acidity which enables survival in the stomach. Source - Human GI tract the only reservoir, transmistion - fecal/oral route. Capsule - none

6 Slide 21 Helicobacter pylori (continued) Chronic gastritis - supeficial mucosal inflammation 100% of patients have infection. Duodenal Peptic Ulcer - Occurs in the setting of chronic gastritis % of patients have infection. Gastric peptic ulcer - similar to duodenal % of patients have infection. Gastric carcinoma - may be a relationship with chronic gastritis. Slide 22 Salmonella enteritidis Aerobic, intracellular Source - Animals are resevoirs, eggs, milk, chicken, other infected food, kitchen bacteria! Can survive on sponges, washcloths, etc. Capsule - polysaccharide Slide 23 Salmonella enteritidis (continued) Enterocolitis - bacteria invades the mucosal of the small and large intesting - diarrhea, usually selflimiting but can be severe and long-lasting. Bacteremia - can result from invastion of the colon mucosa to the blood stream. Slide 24 Salmonella typhi Aerobic, intracellular. Source - Human GI tract is resevoir, horizontal transmission via fecal/oral route, contaminated drinking water. Capsule - Polysaccharide

7 Slide 25 Salmonella typhi (continued) Enteric fever (typhoid fever) - invasion of ileum and colon, progresses to thoracic duct to become a systemic infection - fever, enterocolitis, progressing to bacteremia. If untreated, can last for one month. can be fatal. Carrier state - gall-bladder. Slide 26 Neisseria gonorrhoeae Gram-negative diplococci, aerobic, intracellular. Endotoxin - lipooligosaccharide Source - Humans are only resevoir, STD, or acquired during birth Capsule - probably, but unknown material. Slide 27 Neisseria gonorrhoeae (continued) Male - urethritis, anorectal, pharyngeal. Female - endocervical, anorectal, urethral, vaginal or pharyngeal. PID - ascends to follopian tubes (salpingitis) Neonates - Ophthalmia neonatorum - purulent conjunctivitis. Arthritis - arises from bacteremia, mostly in females and frequently in the knee joints. Slide 28 Neisseria meningitidis Gram-negative diplococci, aerobic, extracellular Endotoxin - lipooligosaccharide Source - Humans the only resevoir, colonizes the nasal pharynx, transmitted via respiratory droplets. Capsule - polysaccharide

8 Slide 29 Neisseria meningitidis (continued) Epidemic meningitis - children, young adults, military barracks. Meningococcemia - sepsis, can be rapidly fatal. Waterhouse-Friderichsen Syndrome - fulminant form of disseminated disease with rapid onset of DIC, bilateral adrenal hrmorrhage, and coma. Prophylaxis - for contacts, rifampin or ciprofloxacin. Slide 30 Moraxella catarrhalis Gram-negative diplococci, aerobic, extracellular. - lipopolysaccharide Source - Human upper respiratory tract and vagina are resevoirs. Transmission via respiratory droplets. Capsule - polysaccharide Slide 31 Moraxella catarrhalis - (continued) Otitis media in children Sinusitis Laryngitis Treaheitis Bacteremia in immunocompromised host. Slide 32 Mycoplasma (no cell wall) Mycoplasma pneumoniae Does not stain with Gram-stain, aerobic extracellular or intracellular - smallest freeliving organism. Plasma membrane contains sterols. Exotoxins - none ] Endotoxins - none Source - Humans are the only resevoir, horizontal droplets via respiratory droplets. Capsule - none

9 Slide 33 Mycoplasma - (no cell wall) Mycoplasma pneumoniae (continued) Atypical pneumonia - most common cause, infection runs from mild to fatal. Most common among college students and military troops. Bronchitis. Slide 34 Mycoplasma - (no cell wall) Mycoplasma hominis Does not stain with Gram-stain, aerobic, extracellular or intracellular Endotoxin - none Source - humans the only resevoir, transmission via sexual contact. Capsule - none Slide 35 Mycoplasma - (no cell wall) Mycoplasma hominis (continued) UTI - acute pyelonephritis, which may progress to PID. Perinatal infection - post-partum or post-abortion fever. Slide 36 Spirochetes Treponema pallidum Tightly coiled spiral rods, mircoaerophilic, extracellular Endotoxin - lipopolysaccharide Source - Transmission via sexual contact. Capsule - no, but complex membrane structure.

10 Slide 37 Spirochete Treponema pallidum Primary syphilis - indolent chancre at the site of entrance ( genatalia, oral, anal, cervical sites). Incubation 3 weeks, symptoms last 4-6 weeks. Contagious during primary stage. Secondary syphilis - maculo-papular rash, first on trunk, then palms, soles, genitalia, fever, sore throat. Can invade any organ (the great pretender). Begins 3weeks - 3 months after untreated primary syphilis. Contagious during secondary stage. Slide 38 Spirochete Treponema pallidum (continued) (continued) Latent syphilis - no symptoms Tertiary syphilis - can occur up to 40 years after latency, much quicker in HIV + individuals. Spirochete found only in the CNS and can effect any organ Neurosyphilis - tabes dorsalis Cardiovascular - ascending aortic aneurysm. Gumma - formation in bones, mucocutaneous sites, or anywhere. Congenital syphilis - transmission from mother. Saddle nose, saber shins, skin rash, etc. Slide 39 Spirochete Borrelia burgdorferi Long coiled rods, aeobic, extracellular. Endotoxin - lipopolysaccharide Source - White-foot mouse, whitetail deer, and Ixodes ticks are the resevoirs. Tick must usually be in place for 24 hours or longer. Capsule - none, but complex membrane structure Slide 40 Spirochete Borrelia burgdorferi (continued) Lyme disease Stage 1 - erythema migrams - annular rash with central clearing, raised borders. Painless and not infectious Stage 2 - Neurologic and cardiac - many symptoms including meningitis, encephalitis A-V block. State 3 - Late or migratory arthritis, chronic neurologic and musculoskeletal involvement. Begins two months to 2 years after beginning stage 1.

11 Slide 41 Chlamydia Chlamydia pneumoniae No peptidoglycan in cell wall - Gram-stain will not stain. Obligate anerobe, obligate intracellular organism. Endotoxin - Lipopolysaccharide - similar to Gram-negative bacteria. Source - Humans are the only resevoir - can survive in macrophages or epithelial cells but killed by PMN s. Slide 42 Chlamydia Chlamydia pneumoniae (continued) Atypical pneumonia - infection can range from asymptomatic to fatal. Effects the elderly most often. Interstitial pneumonia, chills, headache, chest pain. Bronchitis Slide 43 Chlamydia Chlamydia trachomatis No peptidoglycan in cell wall, Gram-stain will not stain, obligate anaerobe, obligate intracellular organism. Endotoxin - lipopolysaccharide - similar to Gram-negative bacteria. Source - humans are the only resevoir, transmission via sexual contact Capsule - none. Slide 44 Chlamydia Chlamydia trachomatis (continued) Male STD - urethritis, epididymitis, proctitis in homosexual men. Female STD - cervicitis, endometritis, salpingitis, PID, proctitis Lymphogranuloma verereum - STD - genital/anal papule arises at site of infection. Trachoma - infection of eye Neonatal infections