1. Infectious Diseases
2008

2. Sepsis SIRS – systemic response Sepsis = SIRS + Infection
Temp >38C (<36C)
HR >90bpm, RR >20bpm (PaCO2<32mmHg)
WBC >12k or >10% bands
Sepsis = SIRS + Infection
Severe Sepsis = Sepsis + Organ Dysfunction
Septic Shock = Sepsis + Hypotension
PIRO severity staging
TLR 4 – LPS (Gm-)
TLR 2 – PGN, LTA (Gm+)
Fever, inflammation, DIC, ARDS, azotemia, olyguria, cellulitis, purpura, GI bleeding, jaundice
Procalcitonin diagnostic?
Tx: ATB, supportive, Activated Protein C (Xigris)

3. Fever / Hyperthermia Fever Hyperthermia
Hypothalamic setpoint shifted up by PGE2 stimulating EP-3
Pyogenic cytokines
Pneumonia, drugs, PE, DVT, C. difficile, fungal infection, MI, NG tubes, IV catheters
Hypothalamic setpoint unchanged
Does not respond to NSAIDS
Heat stroke, hyperthyroidism, atropine, ecstasy, malignant hyperthermia, serotonin syndrome

4. Botulism (Inhalation)
Bioterrorism
Anthrax (Cutaneous)
Bacillus antracis
Botulism (Inhalation)
Bacillus antracis
Direct contact with spores
Jet black lesions (eschars) on skin within 7-10d
Incubation 1d
Tx: Cipro or Doxy q 60d
Vaccine: attenuated Ag
Inhaled spores, no person-to-person transmission
Incubation: 1w to 2 months
Mediastinal widening, pleural effusion, infiltrates
Initial symptoms improve, abrupt onset of fever/ARDS, shock/death within 24-36h
Tx: Penicillin or Cipro/Doxy

5. Clostridium botulinum
Bioterrorism
Anthrax (GI)
Bacillus antracis
Botulism
Clostridium botulinum
Ingested spores, no person-to-person transmission
N/V, severe abd pain, bloody diarrhea, possibly mediastinal widening, rebound tenderness, ascites
Incubation: 1-7d
Tx: Penicillin or Cipro/Doxy
Most poisonous toxin on earth
Not contagious, spread by aerosol/food
12-72 h incubation
N/V, diff see, swallow, speak
Muscle weakness/paralysis

6. Bioterrorism Rice-water diarrhea, dehydration, shock Incubation 12h-5d
Cholera
Vibrio cholerae
Glanders
Burkholderia mallei
Rice-water diarrhea, dehydration, shock
Incubation 12h-5d
Food/water spread
Affects horses, mules, donkeys
Enters cut skin, mucous membranes, inhalation

7. Bioterrorism Nonspecific febrile syndrome, pneumonia
Plague
Yrsinia pestis
Q Fever
Coxiella burnetii
“Black Death”, infected fleas
Bubonic – 1-10 cm buboes on skin w/ edema, flu-like symptoms w/ abd pain
Septicemic - secondary septicemia, thromboses in acral v. leading to necrosis
Penumonic – acute fulminant symptoms, nearly 100% mortality rate
Tx: Streptomycin or Doxycycline
Nonspecific febrile syndrome, pneumonia
Hepatitis, endocarditis, granulomatous complications
Tx: Doxycycline 14-21d

8. Francisella tularensis
Bioterrorism
Smallpox
Variola major
Tularemia
Francisella tularensis
Officially eradicated
Incubation 10-14d
High fever, HA, backache, vomiting, rash on palm/sole
Highly contagious
No tx, vaccine within 3-5d
One of most infectious bacteria in world
Tick/insect bites
Incubation 10-14d
Fever, chills, HA, cough, lethargy, skin ulcers, lymph-adenopahty

9. Bioterrorism GB
Sarin VX
Binary weapon – two non-lethal reagents mix to form sarin gas
Inhibit ACHe, phosphonate esters, light brown oil
If mild: dim vision, salivation, chest tightness
Tx: Atropine and 2PAMCl
1000x more toxic than GB
Persists in soil for 6d
Binary weapon
Inhibits ACHe, phosphonate esters, light brown oil
If severe: stop breathing, paralysis, seizures, LOC

10. Bioterrorism Ricin Waste leftover from processing castor beans
V/D, dehydration, hypotension, hallucinations, seizures, hematuria, multiple organ dysfunction
No tx available

11. Bioterrorism Needs Immediate Treatment, Suspect … Respiratory Symptoms
Acute: Cyanide
Also nerve agents, mustard, lewisite, phosgene, SEB
Delayed: Anthrax, Plague, Tularemia
Also Q Fever, SEB, ricin, mustard, lewisite, phosgene
Neurological Symptoms
Acute: Nerve agents
Also cyanide
Delayed: Botulism
Also VEE-CNS

12. Bioterrorism “Active” Research “Secretly” Developing “Former” Programs
Algeria
Egypt
India
Iran
Israel
N. Korea
Pakistan
Syria
Taiwan
“Secretly” Developing
China
Russia
“Former” Programs
Canada
France
Germany
Japan
S. Africa
UK, US

13. Immunocompromised Deficiencies in Clues Complement IG/B-Cell Phagocyte
T-cell
Clues
Recurrent Neisseria inf
Recurrent pneumonia
Severe presentation
Pneumocystis jiroveci
Burkholderia cepacia
Non-TB Mycobacteria
Aspergillus

14. Complement Deficiency
Hereditary angioedema
C1 inhibitor deficiency
Overactive complement
Minor stressors trigger attacks
C5-9 Deficiency
MAC lysis defect
Neisseria bacteremia
DAF and CD59
Paroxymal nocturnal hemoglobinuria
C1, C3, C4 deficiency
Recurrent pyogenic sinus and respiratory infection
C1q deficiency
90% have SLE

15. Ig/B-Cell Deficiency (Bruton’s) X-Linked Agammaglobulinema
Btk defect, no B-cells, Ig
Multiple pyogenic infections
No live vaccines!
Tx: IvIg
Hyper IgM Syndrome
X-linked, normal B-cell
Low Ig but high IgM
Pneumocystis infections
T-cells lack CD40L
CVID
Low Ig, normal B-cell
Recurrent sinus, respiratory infections
Chronic infections with Giardia, Campylobacter
Tx: ATB, IVIg
IgA deficiency
Associated with CVID
Compensated by others
Secondary Ig deficiencies
Multiple myeloma, leukemia, skin burns

16. Neutrophil Deficiency
Neutropenia
Causes
Blacks have lower counts
Chemotherapy patients
Post-infection, sepsis
Sulfa-drugs, β-lactams
Infections
Mucositis
Ecthyma gangrenosum
Disseminated candidiasis
Aspergillosis
Hereditary Cyclic N.
AD, ELA2 mutation
Predictable cycles
Aphtous stomatitis
Tx: G-CSF, steroids
Chediak-Higashi Syndrome
AR, LYST mutation
Giant lysosomes, ineffective granulopoiesis
Oculocutaneous albinism

17. Neutrophil Deficiency
Job’s Syndrome
Hyper IgE, impaired chemotaxis
STAT3 gene mutation
Facies, scoliosis, skin abscesses, sinusitis
Myeloperoxidase (MPO)
Makes pus green
Converts H2O2 to HOCl
Deficiency impairs this
CGD
Defective NADPH oxidase, no respiratory burst, no killing
Infections with catalase positive organisms
NBT test

18. Spleen “Deficiency” Splenectomy Hyposplenism
Trauma, ITP, Hairy cell leukemia, abscess
Hyposplenism
Autoimmune (Graves, Hashimoto, SLE)
Neoplasia (Hodgkin, CML, Sezary)
Amyloidosis
Alcoholism, elderly, Crohn’s, Sickle cell
Decrease in circulating activated B-cells (75%)
Risk of thalassemia > hodgkins > sphero-cytosis > ITP > sepsis
Infections
S. Pneumoniae (mostly)
Haemophilus, GNR, Neisseria (less common)

19. T-Cell Deficiency DiGeorge’s SCID CD4 T-cell Deficiency
Deletion 22q11.2
No T-cells, hypocalcemia, velocardiofacial defects
SCID
Combined B/T-cell deficiency, lymphopenia, hypogammaglobulinemia
ADA, PNP, RAG1/2, Jak3 gene deficiencies
CD4 T-cell Deficiency
HIV, <300 CD4+/mL
Wiskott-Aldrich
WASP protein
Pyogenic infections, purpura, eczema
High IgA, IgE, low IgM
Infections
Mycobacteria, norcardia, legionella, cryptococcus, histoplasma, pneumocystis, herpesvirus, cryptosporidium, toxoplasma

20. Food Safety Milk pasteurization: 72C for 15s or 63C for 30m
Botulism spores: kill with high heat + acidic
Preservatives: weak acids, nitrites, sulfites, spices
Radiation: γ-irradiation for spices, meats
Survival: Cold – Listeria; Chlorine – Giardia, Cryptosporidum cysts; Anything home processed
Outbreaks: Listeria (microwaved hot dogs), Cyclospora (raspberries), Salmonella, ETEC

21. Tuberculosis Mycobacterium tuberculosis, bovis, africanum
Acid-fast, aerobic non-motile bacillus, reduce nitrates, produce niacin, slow growing
BACTEC blood culture, DAT tests using PCR
PPD (Mantoux) is killed tuberculin, positive if >15 mm, indicates prior infection (LTBI), need CXR
Risks: (normal) 1st year: 3-4%, lifetime: 5-15% (HIV infected) 1st year: 40%, +10% every year
Tx: test susceptibility, give multiple drugs INH + RIF + ETH (+ PZA), INH prophylaxis, hepatotoxicity

22. Tuberculosis Mycobacterium tuberculosis, bovis, africanum
Infected aerosolized droplets, milk (M. bovis), replicates in middle/lower lobes alveolar space, Rasmussen’s aneurysm (pulmonary a.), pleural effusion, sputum with PMNs
Spread to hilar lymph nodes in macrophages
Reactivate in upper lobes, cavities form
Can disseminate through blood (military TB), skin lesions, HA, abd pain, osteomyelitis

23. Leprosy Mycobacterium leprae
Lepromatous Leprosy
Tuberculoid Leprosy
Poor TH1 response
Large # of bacteria in tissue
Infectious, non self-limiting
Tx: rifampicin (monthly) and dapsone (daily) - FREE
Thickened peripheral nerves
Loss of sensation, lesions, peripheral nerve damage, hair loss, disfigurement
Strong TH1 response
Small # of bacteria
Self-limiting
Form granulomas

24. AIDS HIV infection
Lenti- retrovirus, persistent viremia, infects T-cells and macrophages (CD4 + CCR5/CXCR4)
CD4 >500 asymptomatic, increased thrush, shingles, <200 opportunistic infections, <50 MAI, CMV CD4 drops 10/month on average
Transmitted by breast milk (acute), blood, semen Risk: blood 95%, pregnancy 20-33%, MSM 10%, needlestick 1 in 300 (1 in 2400 with therapy) Acute infection “mono”-like w/ rash, ulcers, and w/o tonsil hypertrophy and exudate.

25. AIDS HIV infection
Presents with unexplained anemia, leukopenia, recurrent pneumococcal pneumonias, Kaposi’s sarcoma, thrush, wasting, STD, fever
Screen: ELISA, Confirm: Western Blot, Viral Load: PCR, Severity: CD4 Count
HAART Treatment: NRTI (AZT, 3TC), NNRTI (nevirapine, efavirenz), protease inhibitors (ritonavir, nelfinavir)
Opportunistic Infections: CMV, MAC, PCP, Toxoplasmosis, Cryptococcosis, Candida, PML

26. Gonorrhea Neisseria gonorrhoeae
Gm- diplococci
Infect columnar/cuboidal epi, PMN response, pharynx, anorectal, conjunctivitis
Spread via sex and perinatally
Dysuria w/o frequency or urgency, pain, discharge, cervicitis (PID complication)
Dx by culturing swab for diplococci
Tx with Ceftriaxone IM/cefixime PO

27. Chlamydia C. trachomatis, psittaci, pneumoniae
Intracellular membrane-bound inclusions
Dx with culture, DFA (MicroTrak), ELISA, annual screen sexually active women <25 yo
Tx Azithromycin x 1 or Doxycycline bid x 7d, abstinence x 7d after treatment

28. Chlamydia C. trachomatis, psittaci, pneumoniae
LGV (STD)
Urethritis
Endemic in Africa/SE Asia/ India/S. America
Painless ulcer (heals) to lymphadenopathy (scars) to ulceration of genetalia
Tx: Doxycycline po bid x 21d
NGU
7-14d incubation
Dysuria, scant discharge
Complications
PID, ectopic pregnancy
Reiter’s syndrome (arthritis)

29. Trichomonas Vaginalis
Flagellated motile protozoa
Yellow, purulent, frothy, foul-smelling vaginal discharge, itch, dysuria, lower abd pain
Tx: Metronidazole (ok in pregnancy)

30. Bacterial Vaginosis Gardnerella or Mobiluncus
Mild to moderate thin, gray, adherent vaginal discharge with odor, itch
Clue cells (squamous cells stippled with bacteria)
+Whiff test (fishy smell in KOH)
Tx: Flagyl/Clindamycin (+Metronidazole in pregnant women)

31. Herpes Simplex HSV-1/2 Vesicular lesions, grouped, painful ulcers
Incubation 6 days, primary disease lasts 3wks
Recurrence in 90% of patients
Dx by Tzanck smear (Wright stain) showing multinucleated giant cells
Tx: Acyclovir

32. Syphilis Treponema pallidum
1⁰ - localized painless chancres (ulcerated, non-tender, hard, smooth clean base)
2⁰ (25% untreated) – 3-6 wks after chancre, generalized rash on palms/soles, condylomata lata (flat warts), minimally pruritic
Latency – High Ab titers, 30% progress to 3⁰
3⁰ - “gummas” (granulomatous lesions) neurosyphilis: general paresis (insanity), tabes dorsalis (demyelination of posterior columns - sensation), Argyll Robertson pupil (non-reactive to light), gun-barrel sight

33. Syphilis Treponema pallidum
Congenital: affects muscle, skin, bones; saber shins, saddle nose, Hutchinson’s teeth
Dx: non-specific VDRL, RPR (negative in 1⁰, 3⁰), specific FTA-ABS test (confirmatory)
Tx: (1⁰, 2⁰) Benzathine – Penicillin G IM x 1 (late latent) Benzathine PCN G q week x 3 (neurosyphilis) IV PCN G q 4h

34. Chancroid H. ducreyi
Painful ulcer/ragged edges, painful inguinal lymphadenopathy
Often associated with HIV infection
Incubation 4-7d
Tx: Azithromycin x 1 or Ceftriaxone IM x 1

35. Donovanosis Klebsiella granulomatis
Painless destructive ulcers
No lymphadenopathy
Tx: Doxycycline (+aminoglycoside)

36. TORCH Syndrome
Mother asymtomatic but baby has: small size, hepatosplenomegaly, rash (thrombocytopenia), CNS defects (encephalitis, seizures), jaundice
Toxoplasma
Other (syphilis, HIV)
Rubella
CMV
HSV

37. TORCH Syndrome Toxoplasmosis Other (syphilis)
Detect IgG for previous infection, positive immunity
If not immune: monitor for IgM (acute), avoid undercooked meat, garden soil, wash fruits and vegetables, handwashing
Treat infected infants aggressively
Test all pregnant mothers
If positive, treat monther with penicillin, if allergic to PCN then desensitize
Infected babies commonly show bone lesions, screen CSF for neurosyphilis

38. TORCH Syndrome Other (HIV) Rubella Reduce transmission by
Anti-HIV therapy (zidovudine) during pregnancy and at birth
Give infant antiretroviral therapy for 16 weeks
Cesarean delivery
No breast feeding
Vaccinate mother
Highest risk when mother infected in 1st trimester, no risk after 16 weeks
Infected infant has patent ductus arteriosus

39. TORCH Syndrome CMV HSV Dangerous if mother not immune before pregnancy
If mother not immune, 40% transmission
15% infected infants have neurological symptoms (hearing loss, MR)
Education, handwashing, no vaccine
Perinatal infection by reactivated herpes lesions
Reduce transmission by Cesarean section
Can treat mother with acyclovir around birth time to reduce transmission
Treat infected infants with antiviral therapy

40. Other Congenital GBS VSV B19
Perinatal infection (50%), anogenital screening
Concern in newborn (meningitis), infant (sepsis)
VSV
Primary infection during pregnancy very serious, especially during first 20 weeks (later is mild)
VZV Ig given within 96h of exposure, no vaccine
Fetal infection results in short limbs, skin scars, CNS
B19
Most maternal infections do not lead to fetal infection
Infant symptoms: death, anemia w/ blueberry rash

41. Endocarditis Infection of the endocardial surface or valves
Surface disrupted, platelets/fibrin deposit on exposed collagen forming sterile thrombus, transient bacteremia infect sterile thrombus on low pressure side (Venturi effect), thrombus grows, Ab cannot clear infection
Once established, require ATB to cure
Two types, native or prosthetic valve endoc.

42. Endocarditis NVE PVE Native Valve Endocarditis
Viridans strep most common (followed by S. aureus, Strep, Entero)
If culture negative, can be HACEK, intracellular pathogens, fungi
Prosthetic Valve Endocarditis
Coagulase negative Staph most common in early PVE
Late PVE similar to NVE but coag neg staph still common
Platelets still deposit
Infection of surgical site leads to ring abscess

43. Endocarditis Fever + murmur, persistent bacteremia
Insidious onset of non-specific symptoms
History of heart disease, dental work
Small red lesions on palms/soles, Janeway are non-tender, Osler’s is tender
Roth spots – retinal hemorrhage w/ central pallor
Splinter hemorrhages under nails
Anemia, elevated ESR, TEE echo

44. Endocarditis
Dx: Duke – microbes on valve OR 2 major OR 1 major & 3 minor OR 5 minor
Tx: IV Bactericidal for >4 weeks (Viridans) IV PCN + aminoglycoside (Culture-neg) IV Ceftriaxone (MRSA) Vancomycin + Gentamycin + Rifampin (Entero) Ampicillin + Gentamycin (Fungi) Amphotericin B + SURGERY (2+ embolic event) SURGERY
Prophylaxis: Amoxicillin

45. Respiratory Diseases Rhinitis Influenza
Rhinovirus, parainfluenza, RSV, coronavirus, others
Rhinorrhea, little cellular damage, self-limiting
Symptoms peak days 3-4, persist 1-2 weeks
Late August to early spring, unrelated to temp
Leading infectious cause of death in US
Type A shifts H+N antigens easily, B less so
Vaccine: 2 A strains, 1 B
Amantadine resistance is prevalent

46. Streptococcus pneumoniae Mycoplasma pneumoniae
Respiratory Diseases
Typical Pneumonia
Streptococcus pneumoniae
Atypical Pneumonia
Mycoplasma pneumoniae
Rusty sputum, unilobar
Aspirated into alveolar space, fills with fluid and PMN, then fills with blood (2-3d), then fill with fibrin, then resolve w/o scarring
Asplenic, sickle-cell, agammaglobulinemia at risk
Vaccine has 23 serotypes
Dry cough, myringitis
Inhaled, attaches to respiratory cell, bronchitis infiltrated by plasma cells, lasts 2-6 wks
Similar to Chlamydophila
Unusual over age 40
IgM cold agglutinins

47. Respiratory Diseases Aspiration Pneumonia Chronic, foul sputum
Polymicrobial anaerobic, microaerophilic aspirated into lung
Alcoholics, seizures, tracheoesophageal fistula are risk factors
Tx: Clindamycin PO x 3wks

48. Acute Bacterial Meningitis
S. pneumoniae
vaccine covers most types
N. meningitidis
B cause half infections
vaccine does not have B
H. influenzae
type b vaccine
L. monocytogenes
neonates + elderly
<4w GBS, <18y H.flu, 18-50y S.pneu, >50y L.mono
Stiff neck, Kernig’s sign (leg extension resisted when supine), Brudzinski’s sign (neck flex causes hip flex)
Dx: CNS leukocytosis, positive culture
Tx: Ceftriaxone (+Vanco if community acquired) (+ampicillin if immuno-compromised) + Dexamethasone

49. Acute Viral Meningitis
Enterovirus
Kids > 2 wks old
Summer months
Hand-foot-mouth disease, herpangina
HSV-2
Aseptic meningitis
Genital warts
HIV
Mucosal to viremia to BBB crossing to subarachnoid space to CSF to inflammation
Dx: LP <1000, mostly lymphocytes
Tx: (enterov) nothing (HSV-2) acyclovir (HIV) HAART

50. Chronic Meningitis Fungal Tuberculosis
CSF glucose normal, protein >60, WBC <500
Tuberculosis
CSF protein >>100
AFB smear, +culture
Chronic symptoms with gradual neurologic decline
Dx: history, PE, LP
Tx: most likely diagnosis

51. Intracranial Abscess
Frontal: sinus, teeth Temporal: ear, jaw, sinus Cerebellum: ear, jaw
Strep, GNR, Bacteroides, S. aureus, Fusobacter
MCA: blood, lung, heart
Staph, Strep, Fusobacter, Actinomyces, Anaerobes
Beneath wound
Clostridium, Staph, Strep
Neurologic deficit
1-3d: early cerebritis 4-9d: late cerebritis 10-13d: early capsule >14d: late capsule
Dx: MRI/CT c contrast
Tx: Surgical drainage, manage ICP, culture Metronidazole + ceph + naf/vanco

52. Viral Encephalitis Non-treatable Treatable
EEEV, WEEV, VEEV, St. Louis Encephalitis, West Nile, Polio, Rabies, HIV, Measles
Treatable
HSV-1/2, VZV
Altered mental status, decrease LOC, seizures
Enter brain via blood, retrograde transport, exposed CN-I
Dx: EEG, MRI, LP/PCR
Tx: Acyclovir if treatable

53. Subdural Empyema Bacteriology Inflammatory Source
Strep, Staph, S. pneumoniae, H. influenzae, anerobes, GNR
Usually polymicrobial
Inflammatory Source
50-80% frontal/ethmoid
10-20% mastoid/AOM
5% hematogenous
Altered mental status, focal neuro signs, seizures, like rapidly expanding mass lesion
Reach via emissary vessels or osteomyelitis
Dx: MRI
Tx: Burr holes, craniotomy, manage ICP Metronidazole + Ceftriaxone + Naf/Vanco

54. Epidural Abscess Intracranial Spinal
Intracranial epidural abscess spills over into subdural space
81% associated with subdural empyema, similar bacteriology, diagnositic, treatment
Mainly S. aureus (60-90%)
Abscess covers 4-5 vertebra but can extend entire length
Focal pain, radiculopathy, increasing paralysis
Bacteria enter space by osteomyelitis or hematogenous
Dx: MRI, myelogram
Tx: Surgical drainage Metro + 3rd gen ceph + Vanco

55. Nosocomial Precautions
Standard: gloves, do not recap needles
Infectious: blood, CSF, amniotic/vaginal fluid, semen
Low Risk: saliva, sputum, urine, feces
Surgery: double glove, cover shoes, (face shield)
Contact: gown (+gloves)
VRE, MRSA, C. difficile
Droplet: surgical mask
Influenza, Mumps, Meningococcal Meningitis
Airborne: N-95 mask (particles <5 microns)
TB, Chicken Pox

56. Nosocomial Risks and Numbers
Accidental contaminated needlestick
1:300 HIV (therapy decrease risk 8-fold)
1:30 Hepatitis C
1:3 Hepatitis B (without therapy)
Bacterial drug resistance
63% S. aureus in hospitals are MRSA (2007)
80% E. faecium in this area are VRE
Bacteruria occurs in 100% of patients with indwelling urinary catheters after 30 days

57. UTIs
We prevent UTIs by emptying bladder, valves, normal flora distally, lack glucose, Tamm-Horsfall protein (prevent E. coli attachment)
Lower UTI vs Upper UTI
Lower UTI is the lower poles and the bladder, upper UTI is the upper poles and the kidneys
Uncomplicated vs Complicated
Uncomplicated is adult female who Is not pregnant with normal urinary tract anatomy/fxn
E. coli most common cause of UTIs

58. UTIs Lower UTI Upper UTI Cystitis Urethritis Prostatitis
Dysuria, frequency, urgency
Pyuria tested by urine dipstick
Hematuria, bacteruria
Uncomplicated tx Cipro x 3d
Complicated tx Cipro x 7-14d
Urethritis
Usually due to STD
Prostatitis
Avoid rectal exam if acute
Acute tx: TMP-SMX x 14d
Chronic difficult to treat
Fever common symptom
Pyelonephritis
85% E. coli, 15% entero
Dysuria, frequency, urgency
Fever, CVA/flank tenderness, N/V
“urosepsis” appear septic
Tx ampi + aminoglycoside x 14d
Renal Abscess
Rare complication in DM
Can be caused by S. aureus
Dx CT/Ultrasound
Tx anti-staph PCN, cephalosporin

59. Other UTIs Catheter-related UTI Pregnancy
Most common nosocomial infection
Indwelling = Foley cath
Mostly by E. coli, Proteus, Pseudomonas, Enterococci
Can lead to “urosepsis”
Tx: change the catheter broad spectrum ATB x 3-5d
5% develop asymptomatic bacteruria
Screened at 1st visit and 28th week (or 16th week once)
Associated with premature labor, stillbirth, low infant birth weights
Tx amoxicillin, TMP-SMX, cephalosporin to eradicate

60. Cellulitis Staph. aureus | Strep. pyogenes
Source: anterior nares
Virulence: hemolytic toxin and leukocidin
Source: nasopharynx
Virulence: M-protein and hyaluronidase
Entry by infected oil gland, puncture, bite, rash
High risk: poor lymph drainage, blood supply, neutropenia, hypogammaglobulinemia
Tx: elevate extremity, local heat, ATB
Variants
Impetigo – confined to dermis with crusting
Erysipelas – rapidly spreads, raised borders
Furuncles – local abscesses from infected gland
Carbuncle – several connected furuncles

61. Skin and Soft Tissue Diseases
Synergistic Gangrene
Toxin-Cased Skin Inflammation
Clostridium perfringens is synergistic with GNR, S. aureus causing cellulitis
Necrosis of blood vessels, gangrene of subcutaneous tissue, spreads rapidly
Tx: Surgical removal
Toxic Shock Syndrome:
Staphylcoccus protein
Desquamation of skin of hands, feet, tongue
Hypotension, organ failure
Scarlet Fever
Streptococcus toxin
Diffuse red rash
Scalded-skin syndrome
Staphylococcal toxin
Dehydration, infection

62. Skin and Soft Tissue Infections
Anthrax
Pasteurella Multocida
Bacillus anthracis, a soil bacterium
Marked edema, necrosis surrounding black ulcer
20% fatal if untreated
Common in underdevelopd world
Gm- coccobacillus
Cat bites
Pain/swelling at bite can spread to joints and bone
Tx: opening bite, cleaning, PCN

63. Skin and Soft Tissue Infections
Lymphocutaneous Granulomas
Lyme Disease
Mycobacterium manium or Sporothrix schenckii
Painful papule can ulcerate, spread along lymphatics
M. marinum: exposure to fresh/brackish water
S. schenckii: exposure to plants (rose thorns, hay)
Tx: (fungus) Itraconazole (bac) rifampin+ethambutol
Borrelia burgdorferi
Deer tick bite, expanding disc of redness clearing in center (bulls-eye), lethargy, fever, can progress to arthritis and CNS symptoms
Tx: PCN, tetracycline

64. GI Infections
Transmission: Feces, Food, Fluids, Fingers, Fomites, Fornication, Flies
Lactose+ (CSEEK) Citrobacter, Serratia, E. coli, Enterobacter, Kleb
Lactose- (invas) Salmonella, Shigella, Yersinia
Lactose- (opportunistic) Proteus
Non-motile Gm- rod: Shigella, Kleb, Yersinia

65. Vibrios Vibrio cholerae Vibrio parahemolyticus Vibrio vulnificus
Cholera toxin: increase cAMP results in water loss and dehydration
Rice water diarrhea, no fever, no inflammation
Halophilic, Gulf Coast
Spread via contaminated food/water
Vibrio parahemolyticus
Improperly cooked seafood, oysters
GI year-round, wound infections and septicemia in summer
Vibrio vulnificus
Very virulent
Eating oysters can cause sepsis

66. Pathogenic E. coil ETEC (-toxigenic) EPEC (-pathgenic)
Traveler’s diarrhea
Contaminated food/H2O
Toxins cause diarrhea
LT ↑cAMP, ST ↑cGMP
EPEC (-pathgenic)
Infant diarrhea
Effacing of microvilli, increased signal transd.
Oral/fecal, hands, foods
EHEC (-hemorrhagic)
Bloody diarrhea
Fever, HUS (hemolytic anemia, oliguric RF, thrombocytopenia)
E. coli O157:H7
Shiga-like toxin, Stx
Burgers, apple juice
Do not give ATB
EAEC (-adhesive)

67. Invasive Enteric Pathogens
Shigella
S. dysenteriae (developing countries, shiga toxin stops protein synthesis), sonnei (US), flexneri, boydii
Resistant to acid
70% <15 yo kids
Invade colon, multiply intracellularly
Salmonella
S. typhi (humans), choleraesuis (pigs), typhimurium (US)
Typhoid fever
Bacteria invade and divide in macrophages
Carrier in gallbladder
Tx (typhi) ampicillin, cefriaxone, bactrim

68. Invasive Enteric Pathogens
Yersinia
Y. enterocolitica and pseudotuberculosis
Resist phagocytosis
Blood transfusion disease (grow at 4C)
Belgian chocolates
Mimic appendicitis
Tx: Cipro, TMP-SMX, third gen ceph
Camphylobacter
Small Gm- commas
C. jejuni (most common US gastroenteritis, poultry, unpasteurized milk, water) C. fetus (spread to blood) C. upsaliensis (uncommon)
Damage jejunum mucosa, ulceration, self-limited
Guillan-Barre sequale

69. Helicobacter H. pylori H. cinaedi H. fennelliae Spiral Gm- rods
Corkscrew motility
Urease production
Peptic/duodenal ulcers, gastritis, carcinoma, MALT lymphoma
Fecal-oral transmission
Dx ELISA, urease breath test, silver stain, biopsy
Tx proton pump inhibitor + tetra + metro + bismuth
H. cinaedi
Gastroenteritis, septicemia, proctitis, cellulitis, sepsis in ICH
Homosexual men
Tx amp and/or gent
H. fennelliae
Gastroenteritis, septicemia, proctitis