1. Gram Positive Pathogens
Staphylococcus
Streptococcus
Enterococcus
Listeria monocytogenes
Bacillus anthracis

2. A ‘coccus’ is a spherical bacteria
Staphylococcus tend to cluster in groups
While Streptococcus tend to line up in strings

4. Gram-positive bacteria: Staphylococci

5. Staphylococcus aureus
Staphylococcus aureus causes a variety of suppurative (pus-forming) infections and toxinoses in humans.

6. Important to distinguish Staphylococcus from Streptococcus
Most Staphylococcus are resistant to Penicillin G
Most produce a -lactamase
Or, may be resistant due to mutation of PBP (as in MRSA)
Most Streptococcus are susceptible to Penicillin G

7. Lipoteichoic Acid also present

9. As is Polysaccharide Capsule

10. Proteins that Disable Our Immune Defenses Include:
Protein A: Binds to IgG
Coagulase: leads to fibrin formation around bacteria, preventing phagocytosis
Hemolysins
Leukocidins
Penicillinase

11. Proteins that Tunnel Through Tissue Include:
Hyaluronidase: breaks down proteoglycans in connective tissue
Staphylokinase: Lyses formed fibrin clots
Lipase: Degrades the fat protective layer on surface of skin
Proease: Destroys tissue proteins

12. Exotoxins Produced Include:
Exfoliatin: causes skin to slough off (scalded skin syndrome)
Enterotoxins: cause food poisoning (vomiting and diarrhea)
Toxic Shock Syndrome Toxin (TSST-1): Causes massive T cell response and outpouring of cytokines, resulting in toxic shock syndrome.

13. 3 Major Pathogenic Types of Staphylococcus:
Staphylococcus aureus
Many types of infections
Staphylococcus epidermidis
Most common cause of infection in indwelling prosthetic devices (prosthetic joints, heart valves, etc.)
Staphylococcus saprophyticus
Leading cause of urinary tract infections in sexually active young women

14. Staphylococcal Scalded Skin Syndrome (SSSS)

15. Staphylococcus causes superficial skin lesions such as boils, styes and furunculosis;

16. Staphylococcus also causes more serious infections such as pneumonia, mastitis (inflammation of mammary gland), phlebitis (inflammation of vein, usually in leg), meningitis (inflammation of meninges), and urinary tract infections;

17. Staphylococcus also causes deep-seated infections, such as osteomyelitis (inflammation of the bone) and endocarditis (inflammation of heart).

18. S. aureus is a major cause of hospital acquired (nosocomial) infection of surgical wounds and infections associated with indwelling medical devices.

19. S. aureus causes food poisoning by releasing enterotoxins into food, and toxic shock syndrome by release of superantigens into the blood stream.

20. Superantigens and TSS
Toxic Shock Syndrome can occur via skin, vagina, or pharynx
There has been some indication that it was associated with selected materials used in some ultra-abosorbant tampons. These materials are no longer used in the US.

22. Treatment of Infections Caused by Staphylococcus aureus
Antistaphylococcal penicillins: Nafcillin, oxacillin
First Generation cephalosporins: Cefazolin
Second Generation Cephalosporins: Cefuroxime
Third-generation cephalosporins: Ceftriaxone, cefotaxime, ceftizoxime
-Lactam/ -lactamase inhibitor combinations: Ampicillin-sulbactam, piperacillin-tazobactam, ticarcillin-clavulanate
Carbapenems: Imipenem, meropenem

23. Treatment of Infections Caused by Staphylococcus aureus (NOT methicillin resistant)

24. Treatment of Methicillin-resistant Staphylococcus aureus
Vancomycin
LINK

25. Treatment of Methicillin-resistant Staphylococcus aureus
Linezolid

26. Treatment of Methicillin-resistant Staphylococcus aureus
Streptogramins (Quinupristin-dalfopristin)

27. Treatment of Methicillin-resistant Staphylococcus aureus
Daptomycin
(cubicin)

28. Treatment of Methicillin-resistant Staphylococcus aureus
Tigecycline (Tygacil)
Doxycycline

29. Gram-positive pathogens: Streptococcus pneumoniae

30. Types of Streptococci Group A beta-Hemolytic Streptococci
Streptococcal pharyngitis (Strep throat)
Streptococcal skin infections
Scarlet Fever
Streptococcal toxic shock syndrome
Rheumatic fever
Glomerulonephritis (inflammation of small blood vessels in the kidney)

31. Streptococcus pyogenes

32. Streptococcus pyogenes
Impetigo

33. Treatment of Streptococcus pyogenes+
Penicillin G
Aminopenicillins: Ampicillin
Aminoglycosides are sometimes added for synergy: Gentamicin

34. Treatment of Streptococcus pyogenes+ +
Clindamycin is added for severe invasive Streptococcus pyogenes infections

35. Treatment for Penicillin-resistant Streptococcus pyogenes (and other penicillin resistant Streptococcus)
Vancomycin
Second-generation cephalosporins: Cefuroxime
Third-generation cephalosporins: cefotaxime, ceftriaxone

36. Necrotizing Fasciitis
Necrotizing fasciitis is a rare condition, also known as flesh-eating bacterial disease, that is usually caused by streptococci, but can also be caused by staphylococci.
The disintegration of the skin tissue is due to the production of toxins, which may result in an overly-zealous response of the immune system.

37. Types of Streptococci (Group B)
Viridans Group Streptococci
Dental Infections
Endocardidis

38. Types of Streptococci (Group D)
Streptococcus pneumoniae
S. pneumoniae is a common cause of otitis media (ear infection) and is also a major cause of bacterial pneumonia.

39. Otitis media

40. Streptococcus pneumoniae

41. Treatment of Streptococcus pneumoniae
Ampicillin
Penicillin G (high doses)
Aminopenicillins: Ampicillin (high doses)

42. Treatment of Penicillin-resistant Streptococcus pneumoniae
Second Generation Cephalosoporins: Cefuroxime
Third Generation Cephalosporins: Cefotaxime, Ceftriaxone
Quinolones: Moxifloxacin, Levofloxacin
Vancomycin
Macrolides/ketolines: Telithromycin

43. Enterococci

44. Enterococcus
Enterococci are gram positive cocci, that are normal residents of the GI tract

45. Two common species are Enterococcus faecalis and Enterococcus faecium.
In order of importance these microorganisms cause the following types of infections
Urinary Tract Infections (UTIs)
Intra - abdominal and intra - pelvic abscesses or postsurgery wound infections
Blood stream infections (BSIs)

46. Enterococcus Resistance Mechanisms

47. Treatment of Infections Caused by Enterococcus
Penicillin G
Aminopenicillins: Ampicillin
Extended-spectrum Penicillins: Piperacillin
Carbapenems: Imipenem, meropenem

48. Treatment of Infections Caused by Enterococcus+
For serious infections, add an aminoglycoside for synergy: Gentamicin

49. Treatment for Infections Caused by Penicillin-resistant Enterococci
Vancomycin

50. Treatment for Vancomycin Resistant Enterococci (VRE)
Linezolid
Tetracycline-like: Tigecycline

51. Gram-positive Bacteria: Listeria Monocytogenes

52. Listeria is a food-borne pathogen and is now recognized as a serious hazard by the food industry
Listeria can cause septicemia and meningitis
Listeria seems to particularly affect pregnant women, individuals with weakened immune systems, and newborns.

53. Listeria monocytogenes

54. Treatment of Infections Caused by Listeria monocytogenes
Ampicillin + Gentamicin
If penicillin allergic:
Trimethoprim-sulfamethoxazole +

55. Bacillus anthracis

56. Bacillus anthracis
LINK

57. Bacillus anthracis

58. Treatment of Infections Caused by Bacillus anthracis
Quinolones: Ciprofloxacin

59. Treatment of Infections Caused by Bacillus anthracis
Tetracycline: Doxycycline

60. Treatment of Infections Caused by Bacillus anthracis
For Inhalation Anthrax, a Second Agent Should be Added from the Following List:
Rifampin
Vancomycin
Penicillin G
Ampicillin
Chloramphenicol
Carbapenem: Imipenem
Clindamycin
Macrolide: Clarithromycin

61. Gram-negative Bacteria: Enterobacteriaceae

62. Septic Shock
Septic shock is a condition of hypotension (severely reduced blood pressure) caused by decreased tissue perfusion and oxygen delivery.
Septic shock can lead to multiple organ dysfunction syndrome and death, with the mortality rate approx. 50%. LINK

63. Enterobacteriaceae Shigella Escherichia coli Yersinia pestis
Klebsiella pneumoniae
Escherichia coli
Salmonella

64. Escherichia coli

65. Klebsiella

66. Proteus

67. Escherichia coli.
E. coli is a normal resident of the human intestinal tract and most strains are harmless.
However, some strains acquire the ability to produce toxins and to invade the blood stream.

68. Certain strains of E. coli
Certain strains of E. coli., like serotype O157:H7, however, can cause serious illness.
E. coli is also a leading cause of urinary tract infections in women and also of meningitis in neonates.
Link
LINK

69. Treatment of Infections Caused by: E. coli., K. pneumoniae, Proteus
Aminopenicillins: Ampicillin
First Generation Cephalosporins: Cefazolin
Sulfa drugs: Trimethoprim-sulfamethoxazole
Quinolones: Ciprofloxacin, levofloxacin, moxifloxacin

70. Treatment of Resistant Infections Caused by: E. coli. , K
Treatment of Resistant Infections Caused by: E. coli., K. pneumoniae, Proteus
Third Generation Cephalosporins: Cefoxaxime, ceftriaxone, ceftizoxime
Monobactam: Aztreonam

71. Treatment of Resistant Infections Caused by: E. coli. , K
Treatment of Resistant Infections Caused by: E. coli., K. pneumoniae, Proteus
Extended Spectrum penicillins + b-lactamase inhibitor: Piperacillin-tazobactam, ticarcillin-clavulanate

72. Treatment of Resistant Infections Caused by: E. coli. , K
Treatment of Resistant Infections Caused by: E. coli., K. pneumoniae, Proteus
Meropenem
Carbapenems: Imipenem, meropenem, ertapenem
Carbapenem + aminoglycoside in serious infections: Add Gentamicin, Tobramycin, amikacin

73. Treatment of Infections Caused by: Enterobacter, Serratia, Citrobacter, Providencia, and Morganella Spp.
Carbapenems: Imipenem, meropenem, ertapenem
Sulfa Drugs: Trimethoprim-sulfamethoxazole
Quinolones: Ciprofloxacin, levofloxacin
Fourth Generation Cephalosporins: Cefepime
+ aminoglycoside: Gentamicin, tobramycin, amikacin

74. Treatment of Infections Caused by: Salmonella enterica, Shigella spp.
Quinolones: Ciprofloxacin
Third-generation cephalosporins: Cefotaxime, ceftriaxone, ceftizoxime
Macrolides: Azithromycin

75. Treatment of Infections Caused by: Yersinia spp.
LINK
Historical Link

76. Treatment of Infections Caused by: Yersinia spp.
Gentamycin
Aminoglycosides: Gentamicin, streptomycin

77. Treatment of Infections Caused by: Yersinia spp.
Tetracyclines: Doxycycline

78. Treatment of Infections Caused by: Yersinia spp.
Quinolones: Ciprofloxacin
Sulfa drugs

79. Gram-negative Bacteria: Pseudomonas

80. Pseudomonas

81. Pseudomonas aeruginosa

82. Resistance of Pseudomonas

83. Treatment of Infections caused by Pseudomonas aeruginosa
Extended spectrum penicillins: Piperacillin, Ticarcillin
Third Generation Cephalosporins: Ceftazidime
Fourth-generation Cephalosporins: Cefepime
Carbapenems: Imipenem, meropenem
Monobactams: Aztreonam
Quinolones: Ciprofloxacin, Levofloxacin
Aminoglycosides: Gentamicin, tobramycin, amikacin

84. Treatment of Serious Infections Caused by Pseudomonas aeruginosa
Antipseudomonal b-lactam + aminoclycoside: Ceftazidime + Tobramycin

85. Treatment of Serious Infections Caused by Pseudomonas aeruginosa
Extended-spectrum penicillin + antipseudomonal quinolone: Piperacillin + Ciprofloxacin

86. Neisseria

87. Neisseria meningitidis

88. The meninges are a series of membranes surrounding the central nervous system
They consist of three layers: the dura matter, the arachnoid matter, and the pia matter

89. Neisseria meningitidis

91. Neisseria meningitidis

92. Neisseria gonorrhoeae

93. Neisseria gonorrhoeae

94. Treatment of Infections Caused by Neisseria meningitidis
Penicillin G
Third generation cephalosporins: Ceftriaxone, cefotaxime
Chloramphenicol

95. Treatment of Infections Caused by Neisseria Gonorrhoeae
Third Generation Cephalosporins: Ceftriaxone, cefixime

96. Curved Gram Negative Bacilli
Campylobacter jejuni,
Helicobacter pylori,
Vibrio cholerae

97. Campylobacter jejuni
Camphylobacter jejuni is a common cause of gastroenteritis.

99. Campylobacter jejuni

100. Treatment of Infection Caused by Campylobacter jejuni
Azithromycin
Macrolides: Erythromycin, azithromycin, clarithromycin
Link

101. Treatment of Infection Caused by Campylobacter jejuni
Quinolones: Ciprofloxacin

102. Helicobacteri pylori

103. Helicobacter pylori

104. Helicobacter pylori

105. Duodenal Peptic Ulceration Caused by Helicobacter pylori

106. Treatment of Infection Caused by Helicobacter pylori
Amoxicillin + clarithromycin + proton pump inhibitor
Metronidazole + clarithromycin + proton pump inhibitor
Bismuth subsalicylate + metronidazole + tetracycline + proton pump inhibitor

107. Vibrio cholerae
LINK

108. Vibrio cholerae
Cholera is a bacterial infection of the small intestine.
Cholera is spread by eating or drinking contaminated water or food.

110. Vibrio cholerae
The main symptoms of cholera are watery diarrhea and vomiting, which can lead to rapid dehydration and death.

111. Treatment of Infection Caused by Vibrio cholerae
Tetracyclines: tetracycline, doxycycline
Sulfa drugs: Trimethoprim-sulfamethoxazole
Quinolones: Ciprofloxacin
Macrolides: Erythromycin, Azithromycin

112. Haemophilus influenzae

113. Haemophilus influenzae
Haemophilic means ‘blood loving’. The organism requires a blood-containing medium for growth
Influenzae: The bacterium often attacks the lungs of a patient with viral influenza.
Since the organism was frequently isolated from the lungs of patients during the 1890 and 1918 influenza pandemics, scientists incorrectly concluded that the bacterium was the causative agent.

114. Haemophilus influenzae

115. Haemophilus influenzae

116. Treatment of Infections Caused by Haemophilus influenzae
Aminopenicillins + b-lactamase inhibitor:
Amoxicillin/clavulanate
Ampicillin/sulbactam
Second-generation cephalosporin
Cefuroxime
Third-generation cephalosporin
Ceftriaxone
Cefotaxime

117. Bordetalla pertussis

118. Bordetalla pertussis causes a violent cough called ‘whooping cough’

119. Bordetella pertussis
LINK

120. Treatment of Infection Caused by Bordetella pertussis
Macrolides: Azithromycin, Clarithromycin, Erythromycin

121. Moraxella catarrhalis
Causes otitis media, pneumonia, and sinusitis
Usually produces b-lactamase

122. Treatment of Infections Caused by Moraxella catarrhalis
Extended spectrum penicillins: piperacillin, ticarcillin
-lactam/-lactamase inhibitor combinations: piperacillin/tazobactam, ticarcillin/clavulanate
Second and third-generation cephalosporins

123. Acinetobacter Recent outbreak among soldiers in Iraq
Second leading cause of infection among troops during the Vietnam conflict

124. Acinetobacter

125. Treatment of Infection Caused by Acinetobacter
Sulbactam
Carbapenems
Quinolones

126. Anaerobic Bacteria Gram positive: Clostridia spp.

127. Clostridium tetani
Clostridium tetani is the etiologic agent of tetanus
Characterized by persistent tonic spasm, usually involving the masseter muscles (lockjaw)
Usually caused by deep wound becoming infected with C. tetani spores.

128. Clostridium botulinum
Clostridium botulinum is usually acquired by ingestion of food contaminated with C. botulinum spores
Botulinum toxin leads to cranial neuroopathies and weakness rather than muscular spasm.
Link
LINK

129. Botulinum Toxin (Botox)
Botulinum toxin is a neurotoxic protein produced by Clostridium botulinum
It was discovered in the 1950’s that injecting small amounts decreased muscle activity by blocking release of acetylcholine at the neuromuscular junction

130. Botulinum Toxin (Botox)

131. LINK
LINK

132. Treatment of Infections Caused by Clostridium spp.
Penicillin G
Metronidazole (may be associated with better outcomes)

133. Clostridium difficile

134. Clostridium difficile
LINK

135. Treatment of Infections Caused by Clostridium difficile
Oral metronidazole
Oral vancomycin

136. Clostridium perfringens is the cause of gas gangrene

137. Gas Gangrene
Gangrene comes from the Greek ‘gangraina’ meaning ‘putrefication of tissues’
Dry gangrene often occurs in the toes and feet of elderly patients
Wet gangrene occurs in naturally moist tissues, such as the mouth, bowel, lungs.

138. Gas gangrene is due to infection by Clostridium perfringens, which produces gas within the tissues.
Such gas-producing infection spreads very rapidly, and should be considered a medical emergency.

139. Treatment of Infections Caused by Clostridium perfringens
Penicillin + one of the following:
Clindamycin
Tetracycline
Metronidazole

140. Hyperbaric Oxygen Therapy
One treatment for gas gangrene includes hyperbaric oxygen therapy

141. Anaerobic Gram-negative Bacteria

142. Common Anaerobic Gram-negative Pathogens
Bacteroides fragilis
Usually produces b-lactamase
Prevotella
Porphyromonas

143. Treatment of Anaerobic Gram-negative Infections
b-lactam/b-lactamase inhibitor combinations
Ampicillin-sulbactam
Piperacillin-tazobactam
Ticarcillin-clavulanate
Carbapenems: Imipenem, Meropenem, Ertapenem
Metronidazole

144. Atypical Bacteria: Chlamydia

145. Chlamydia trachomatis
One of the most common sexually transmitted diseases
Also a leading cause of blindness in some parts of the world
LINK

146. Chlamydia is a bacterial infection of the genital tract spread through sexual contact. If untreated, it can result in various medical complications, including damage to the reproductive organs.
The disease affects both women and men, although reported cases for women greatly exceed those for men. Chlamydia affects people in all age groups, but it is particularly prevalent among teenagers and young adults. According to the U.S. Centers for Disease Control and Prevention (CDC), the infection is most prevalent among women aged 20 to 25.

147. Chlamydia trachomatis
Some signs and symptoms that may be present in people infected with chlamydia are:
Abnormal discharge from the penis or vagina
Burning sensation during urination
Lower abdominal or back pain
Nausea
Fever
Pain during intercourse
Burning or itching around the head of the penis
Swollen or tender testicles
Bleeding between menstrual cycles
Proctitis (inflammation of the rectum)

148. Life Cycle of Chlamydia trachomatis
Link
USMLE Study Song

150. Treatment of Infections Caused by Chlamydia trachomatis
Tetracyclines
Tetracycline
Doxycycline
Macrolides
Azithromycin
Erythromycin
Telithromycin
Quinolones
Ofloxacin
Moxifloxacin
Gemifloxacin

151. Mycoplasma pneumoniae

152. Mycoplasma pneumoniae

153. Treatment of Infections Caused by Mycoplasma pneumoniae
Macrolides: Azithromycin, clarithromycin, erythromycin telithromycin
Tetracyclines: Tetracycline, doxycycline
Quinolones: Levofloxacin, moxifloxacin, gemifloxacin

154. Atypical Bacteria: Legionella
Legionella pneumophila is the most common species, and is the causative agent of Legionaires’ disease
Once in the lung, Legionella organisms are taken up by macrophages and multiply within them.

155. Legionalla pneumophila

157. Treatment of Infections Caused by Legionella pneumophila
Macrolides: Azithromycin
Quinolones: Levofloxacin, moxifloxacin

158. Brucella
Brucellosis is a disease of animals, that is occasionally transmitted to humans
Contact with animals and/or ingestion of unpasteurized milk or cheese are risk factors

159. Brucella

160. Brucella

161. Treatment of Infections Caused by Brucella spp.+
Doxycycline + rifampin
Doxycycline + gentamicin
Doxycycline + streptomycin

162. Francisella tularensis
Tularemia is contracted by contact with infected animals (squirrels) or through an arthropod vector (fleas, ticks, etc.)

163. Francisella tularensis

165. Treatment of Infections Caused by Francisella tularensis
Aminoglycosides: Streptomycin, Gentamicin
Tetracyclines: Tetracycline, doxycycline

166. Rickettsia spp

167. Rickettsia rickettsii
Rocky Mountain spotted fever is the most severe and most frequently reported rickettsial illness in the United States. The disease is caused by Rickettsia rickettsii, a species of bacteria that is spread to humans by ixodid (hard) ticks.

168. Treatment of Infections Caused by Rickettsia spp.
Tetracyclines
Doxycycline
Tetracycline

169. Spirochetes: Treponema pallidum

170. Treponema pallidum
LINK

171. Treponema pallidum

172. Treponema pallidum

173. LINK

174. Treatment of Infections Caused by Treponema pallidum
Penicillin G (including benzathine penicillin)
Tetracyclines
Third Generation Cephalosporins

175. Penicillin procaine
Penicillin benzathine
These particular salts of penicillin are injected intramuscularly and absorbed slowly over a period of time.

176. Penicillin G benzathine

177. Procaine penicillin G

178. Borrelia borgdorferi

179. Borrelia burgdorferi

180. Borrelia burgdorferi is the causative agent of Lyme Disease

181. Treatment of Infections Caused by Borrelia burgdorferi
Tetracyclines: Doxycycline
Aminopenicillins: Amoxicillin

182. Leptospira interrogans

183. Leptospira interrogans

184. Treatment of Infection Caused by Leptospira interrogans
Tetracyclines: Doxycycline
Aminopenicillins: Amoxicillin
Severe Disease can be treated with Penicillin G, Ampicillin, or Ceftriaxone

185. Mycobacteria Mycobacterium tuberculosis Mycobacterium avium complex
Mycobacterium leprae

186. Mycobacterium tuberculosis
Link

187. Mycobacterium tuberculosis

188. Mycobacterium tuberculosis

189. Treatment of Infections Caused by Mycobacterium tuberculosis
Active Disease
Isoniazid + Rifampin + Pyrazinamide + Ethambutol for two months
Followed by: Isoniazid + Rifampin for Four months
Latent Disease
Isoniazid for 9 months

190. Mycobacterium avium complex

191. Mycobacterium avium complex

192. Treatment of Infections Caused by Mycobacterium avium complex (MAC)
Clarithromycin + ethambutol + rifabutin

193. Mycobacterium leprae

194. Mycobacterium leprae

195. Leprosy

196. Treatment of Infections Caused by Mycobacterium leprae
Dapsone + rifampin + clofazimine