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► Med 11 - USMLE 1 > Micro Systems > Flashcards

Flashcards in Micro Systems Deck (113):
1

Normal Dominant Flora of Skin

Staphylococcus epidermidis

2

Normal Dominant Flora of Nose

Staph epidermidis. Colonies by Staph aureus

3

Normal Dominant Flora of Oropharynx

Viridans Group Strep

4

Normal Dominant Flora of Dental plaques

Streptococcus mutans

5

Normal Dominant Flora of Colon

Bacteroides fragilis (more)
E. coli (less)

6

Normal Dominant Flora of Vagina

Lactobacillus
Colonies by E coli and GBS

7

Neonates delivered by Cesarean section re flora?

They have no flora but are rapidly colonized after birth

8

Staph aureus and B cereus food poisoning course

Starts quickly and ends quickly

9

Contaminated seafood

Vibrio parahaemolyticus and V vulnificus (can cause wound infection from contact with contaminated water or shellfish)

10

Reheated rice

"be serious"
B cereus

11

Meats, Mayonnaise, Custard

S aureus

12

Reheated meat dishes leading to watery diarrhea

Clostridium perfringens

13

Improperly canned foods (bulging cans)

Clostridium botulinum

14

Undercooked meat

E coli O157:H7

15

Poultry, meat, eggs

Salmonella

16

Bugs that can mimic appendicitis

Yersinia enterocolitica causes mesenteric adenitis
Nontyphoidal Salmonella
Campylobacter jejuni

17

Causes of Bloody Diarrhea with signs

Campylobacter: Comma or S shaped, grows at 42
Salmonella: Lac-, Flagella
Shigella: Lac-, low ID50
EHEC, EIEC
Yersinia enterocolitica: Daycare outbreaks, pseudoappendicitis
Entamoeba histolytica

18

Causes of Watery Diarrhea

Enterotoxigenic E coli: Traveler's, ST and LT toxin
V Cholerae: comma-shaped, rice-water
C difficile: bloody w/ pseudomembranous colitis
C perfringens: also gas gangrene
Protazoa: Giardia, Cryptosporidium (in immunocompromised)
Rotavirus, Norovirus

19

Pneumonia in neonate (less than 4 weeks)

GBS, E coli

20

Pneumonia in children (4 weeks to 18 years)

"Runts May Cough Chunky Sputum"
RSV, Mycoplasma, C. pneumoniae (school age), Chlamydia trachomatis (infant to 3 years), Streptococcus pneumoniae

21

Pneumonia in adults (18 years to 40 years)

Mycoplasma, C pneumoniae, S pneumoniae

22

Pneumonia in adults (40 years to 65 years)

S pneumoniae, H influenzae, Anaerobes, Viruses, Mycoplasma

23

Pneumonia in elderly

S pneumoniae, Influenza, Anaerobes, H influenzae, H influenzae, Gram- rods

24

Special Nosocomial Infections

Staph, Enteric Gram negative Rods

25

Special Immunocompromised infections

Staphylococcus, Enteric Gram- rods, Fungi, Viruses, Pneumocystis jirovecii - w/ HIV

26

Special infections with aspiration

Anaerobes

27

Special infections w/ EtOH and IV drug users

S pneumoniae, Klebsiella, Staph

28

Special infections in CF

Pseudomonas, S aureus, S pneumoniae

29

Special infections in Post-Viral pt

Staph, H influenzae, S pneumoniae

30

Bugs that cause atypical pneumonia

Mycoplasma, Legionella, Chlamydia

31

Meningitis in a newborn (0 to 6 months)

GBS, E coli, Listeria

32

Meningitis in a child (6 months to 6 years)
PathoPhys
Presentation

Streptococcus pneumoniae
Neisseria meningitidis
Enteroviruses
Haemophilus influenzae type B
Polio
Last 2 in non immunized children
Microbe colonizes nasopharynx leading to myalgias and paralysis

33

Meningitis in a adults (6 years to 60 years)

S pneumoniae
N meningitidis (#1 in teens)
Enteroviruses
HSV

34

Meningitis in elderly (60+)

S pneumoniae
Gram- rods
Listeria

35

Meningitis Treatment

Ceftiazone and Vancomycin empirically
Add ampicillin if Listeria is suspected

36

Viral causes of meningitis

Enterovirus (esp coxsackievirus), HSV2 (HSV1 = encephalitis), HIV, West Nile Virus, VZV

37

Meningitis in HIV pt

Cryptococcus, CMV, toxoplasmosis (brain abscess), JC virus (PML)

38

Recent changes in H influenzae meningitis

Decreased with introduction of conjugate H influenzae vaccine in last 10-15 years.
Todays cases are in un-immunized children

39

CSF findings in Bacterial meningitis
Opening pressure
Cell type
Protein
Sugar

Opening pressure ↑
PMNs
Protein ↑
Sugar ↓

40

CSF findings in Viral meningitis
Opening pressure
Cell type
Protein
Sugar

Opening pressure Normal or ↑
Lymphocytes
Protein is Normal or ↑
Sugar is Normal

41

CSF findings in Fungal/TB meningitis
Opening pressure
Cell type
Protein
Sugar

Opening pressure ↑
Lymphocytes
Protein is Normal or ↑
Sugar ↓

42

Osteomyelitis w/ nothing else

S aureus

43

Osteomyelitis in sexually active individual

Neisseria gonorrhoeae (rare), septic arthritis more common

44

Osteomyelitis in diabetic or IV drug user

Pseudomonas aeruginosa, Serratia

45

Osteomyelitis in Sickle cell disease

Salmonella

46

Osteomyelitis in Prosthetic replacement

S aureus and S epidermidis

47

Osteomyelitis in Vertebral disease

Mycobacterium Tuberculosis (Pott's disease)

48

Osteomyelitis in cat and dog bite/scratches

Pasteurella multocida

49

Osteomyelitis
Mostly in...
Signs

Children
Elevated CRP and ESR

50

UTIs
Presentation
Labs
PathoPhys
Causes in males
Causes in elderly
Can progress to...

Dysuria, Frequency, Urgency, Suprapubic pain
WBCs (but not casts) in urine
Males: infants w/ congenital defects, vesicoureteral reflux
Elderly: Enlarged prostate
Pyelonephritis

51

Pyelonephritis presentation

Fever, Chills, Flank pain, CVA tenderness, Hematuria, WBC casts

52

UTIs in women
Frequency
Predisposing factors

10x more likely in women because of shorter urethra colonized by fecal flora
Obstruction, Kidney surgery, Catheterization, GU malformation, Diabetes, Pregnancy

53

UTI Dx markers

+Leukocyte esterase test = bacterial UTI
+Nitrite test = Gram- bacterial UTI
+Urease test = Proteus, Klebsiella
-Urease test = E coli or Enterococcus

54

UTI bugs

E coli: #1. Green metallic sheen on EMB
Staph saprophyticus: #2
Klebsiella: #3. Large mucoid capsule + viscous colonies
Serratia: Red pigment. Nosocomial and drug resistant
Enterobacter cloacae: Nosocomial and drug resistant
Proteus mirabilis: Swarming on agar, Urease+, Struvite stones
Pseudomonas aeruginosa: Blue-green pigment, fruity odor. Nosocomial and drug resistant

55

ToRCHeS Infection
What are they?
Presentation

Mother --> fetus. Transplacental in most cases or via delivery (HSV2)
HSM, Jaundice, Thrombocytopenia, Growth retardation

56

Names of ToRCHeS Infection

Toxoplasma gondii
Rubella
CMV
HIV
HSV2
Syphilis

57

Toxoplasma gondii
Mode of transmission
Maternal manifestation
Neonatal manifestation

Cat feces or ingestion of undercooked meat
Usually asymptomatic; Lymphadenopathy (rarely)
Classic Triad: Chorioretinitis, Hdyrocephalus, and Intracranial calcification

58

Rubella
Mode of transmission
Maternal manifestation
Neonatal manifestation

Respiratory droplets
Rash, Lymphadenopathy, Arthritis
Classic triad: PDA (or pulmonary artery hypoplasia), Cataracts, and Deafness
Blueberry muffin rash

59

CMV
Mode of transmission
Maternal manifestation
Neonatal manifestation

Sexual contact, organ transplant
Usually asymptomatic. Mononucleosis-like illness
Hearing loss, Seizures, Petechial rash, Blueberry muffin rash

60

HIV
Mode of transmission
Maternal manifestation
Neonatal manifestation

Sexual contact, Needlestick
Variable presentation depending on CD4 count
Recurrent infections, Chronic diarrhea

61

HSV2
Mode of transmission
Maternal manifestation
Neonatal manifestation

Skin or mucous membrane contact
Usually asymptomatic. Herpetic (vesicular lesions)
Encephalitis, Herpetic (vesicular) lesions

62

Syphilis
Mode of transmission
Maternal manifestation
Neonatal manifestation

Sexual contact
Chancre (primary) and disseminated rash (secondary) are the 2 stages likely to result in fetal infection
Stillbirth, Hydrops Fetalis
If child survives presents with facial abnormalities [notched teeth (Hutchinson's teeth), saddle nose, short maxilla, Dry wrinkled skin, yellow-brown hue, hemorrhagic rhinitis], saber sings, CN VIII deafness

63

Childhood rash that begins at head and moves down --> fine truncal rash

Rubella virus
Usually associated with lymphadenopathy

64

Childhood rash beginning at head and moving down preceded by cough, coryza, conjunctivitis, and blue-white spots on buccal mucus

Measles

65

Childhood vesicular rash beginning on trunk and spreading to face and extremities with lesions of different ages

Chickenpox (VZV)

66

Childhood (infant) macular rash over body appears after several days of high fever, febrile seizures

Roseola (HHV6)

67

Childhood "slapped cheek" rash on face

Erythema infectionsum (parvovirus B19)
Can cause hydrops fetalis in pregnant women)

68

Childhood erythematous sandpaper rash with fever and sore throat

Scarlet fever from Strep pyogenes

69

Childhood vesicular rash on palms and soles with ulcers in oral mucosa

Hand-Foot-Mouth Disease (Coxsackievirus A)

70

Urethritis, Cervicitis, PID, Prostatitis, Epididymitis, arthritis, Creamy purulent discharge

Neisseria gonorrhoeae

71

Painless Chancre

Primary syphilis (Treponema pallidum)

72

Fever, lymphadenopathy, Skin rashes, Condylomata lata

Secondary syphilis (Treponema pallidum)

73

Gummas, Tabes Dorsalis, General Paresis, Aortitis, Argyll Robertson pupil

Tertiary syphilis (Treponema pallidum)

74

Painful genital ulcer with inguinal adenopathy

Chancroid caused by Haemophilus ducreyi
"It's so painful, you DO CRY"

75

Painful penile, vulvar, or cervical vesicles and ulcers
Fever, Headache, Myalgia

Genital herpes
HSV2. Less commonly HSV1

76

Urethritis, Cervicitis, Conjunctivitis, Reiter's Syndrome, PID

Chlamydia from Chlamydia trachomatis (D-K)

77

Infection of lymphatics, Genital ulcers, Lymphadenopathy, Rectal strictures

Lymphogranuloma venereum from Chlamydia trachomatis (L1-L3)

78

Vaginitis, Strawberry colored mucosa, motile in wet prep

Trichomonas vaginalis

79

Opportunistic infections Kaposi sarcoma, Lymphoma

AIDS from HIV

80

Genital warts, Koilocytes

HPV 6 and 11

81

Jaundice

HBV

82

Non-Inflammatory, Malodorous Discharge (fishy smell), Positive whiff test, Clue cells

Gardnerella vaginalis

83

PID
Causes
Presentation
May include...

Chlamydia trachomatis (subacute, often undiagnosed), Neisseria gonorrhoeae (acute)
Cervical motion tenderness (chandelier sign), Purulent cervical discharge
Salpingitis, Endometriosis, Hydrosalpinx, Tubo-Ovarian Abscess

84

PID can lead to...

Hugh-Curtis Syndrome
Infection of the liver capsule and violin string adhesion of parietal peritoneium to liver

85

Salpingitis is a risk factor for...

Ectopic pregnancy, Infertility, Chronic pelvic pain, Adhesions

86

Nosocomial infections in a newborn nursery

CMV, RSV

87

Nosocomial infections in urinary catheterizations

E coli, Proteus, Mirabilis

88

Nosocomial infections in Respiratory Therapy Equipment

Pseudomonas aeruginosa
"Presume Pseudomas when Air or Water are involved"

89

Nosocomial infections for work in renal dialysis unit

HBV

90

Nosocomial infections in hyperalimentation

Candida albicans

91

Nosocomial infections in water aerosols

Legionella

92

Painful throat. Grayish oropharyngeal exudate in painful throat in an un-immunized child

Corynebacterium diphtheriae elaborating toxin that causes necrosis pharynx, cardiac and CNS tissue

93

Fever, dyspnea, Drooling, difficulty breathing due to cherry red edematous epiglottis in un-immunized child

H influenzae type B
Can cause epiglottitis in fully immunized children too

94

Pus, Empyema, Abscess

S aureus

95

Pediatric infection

Haemophilus influenzae (including epiglottitis)

96

Pneumonia in CF or burn pt

Pseudomonas aeruginosa

97

Branching rods in oral infection w/ sulfur granules

Actinomyces israelii

98

Traumatic open wound

Clostridium perfringens

99

Surgical wound

S aures

100

Dog or cat bite

Paseurella multocida

101

Currant jelly sputum

Klebsiella

102

+PAS stain

Tropheryma whippelei

103

Sepsis/Meningitis in a newborn

GBS

104

Healthcare provider

HBV from needlestick

105

Fungal infection in diabetic or immunocompromised pt

Mucor or Rhizopus

106

Asplenic pt

Encapsulated microbes
"SHiN"
S pneumoniae, H influenzae type B, N Meningitidis

107

Chronic Granulomatous disease

Catalase+ microbes esp S aureus

108

Neutropenic pt

Candida albicans (systemic), Aspergillus

109

Facial nerve palsy

Borrelia burgdorferi (Lyme disease)

110

Infectious cause of pericarditis

Coxsackie B

111

Best Way to Prevent Tetanus?

Vaccinate Mother

112

Most common causes of UTIs?

E coli
Staph saprophyticus

113

Sepsis with black rash

Pseudomonas