Transcript Infectious Diseases

Infectious Diseases
2008
Sepsis
• SIRS – systemic response
– 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
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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)
Fever / Hyperthermia
Fever
• Hypothalamic setpoint
shifted up by PGE2
stimulating EP-3
• Pyogenic cytokines
• Pneumonia, drugs, PE, DVT,
C. difficile, fungal infection,
MI, NG tubes, IV catheters
Hyperthermia
• Hypothalamic setpoint
unchanged
• Does not respond to NSAIDS
• Heat stroke,
hyperthyroidism, atropine,
ecstasy, malignant
hyperthermia, serotonin
syndrome
Bioterrorism
Anthrax (Cutaneous)
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
Botulism (Inhalation)
Bacillus antracis
• Inhaled spores, no personto-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
Bioterrorism
Anthrax (GI)
Bacillus antracis
Botulism
Clostridium botulinum
• Ingested spores, no personto-person transmission
• N/V, severe abd pain,
bloody diarrhea, possibly
mediastinal widening,
rebound tenderness, ascites
• Incubation: 1-7d
• Most poisonous toxin on
earth
• Not contagious, spread by
aerosol/food
• 12-72 h incubation
• N/V, diff see, swallow, speak
• Muscle weakness/paralysis
• Tx: Penicillin or Cipro/Doxy
Bioterrorism
Cholera
Vibrio cholerae
• Rice-water diarrhea,
dehydration, shock
• Incubation 12h-5d
• Food/water spread
Glanders
Burkholderia mallei
• Affects horses, mules,
donkeys
• Enters cut skin, mucous
membranes, inhalation
Bioterrorism
Plague
Yrsinia pestis
• “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
Q Fever
Coxiella burnetii
• Nonspecific febrile
syndrome, pneumonia
• Hepatitis, endocarditis,
granulomatous
complications
• Tx: Doxycycline 14-21d
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, lymphadenopahty
Bioterrorism
GB
Sarin
• Binary weapon – two nonlethal reagents mix to form
sarin gas
• Inhibit ACHe, phosphonate
esters, light brown oil
• If mild: dim vision,
salivation, chest tightness
• Tx: Atropine and 2PAMCl
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VX
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
Bioterrorism
Ricin
• Waste leftover from
processing castor beans
• V/D, dehydration,
hypotension, hallucinations,
seizures, hematuria,
multiple organ dysfunction
• No tx available
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
Bioterrorism
• “Active” Research
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Algeria
Egypt
India
Iran
Israel
N. Korea
Pakistan
Syria
Taiwan
• “Secretly” Developing
– China
– Russia
• “Former” Programs
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Canada
France
Germany
Japan
S. Africa
UK, US
Immunocompromised
• Deficiencies in
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Complement
IG/B-Cell
Phagocyte
T-cell
• Clues
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Recurrent Neisseria inf
Recurrent pneumonia
Severe presentation
Pneumocystis jiroveci
Burkholderia cepacia
Non-TB Mycobacteria
Aspergillus
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
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
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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
Neutrophil Deficiency
• Neutropenia
– Causes
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Blacks have lower counts
Chemotherapy patients
Post-infection, sepsis
Sulfa-drugs, β-lactams
– Infections
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Mucositis
Ecthyma gangrenosum
Disseminated candidiasis
Aspergillosis
• Hereditary Cyclic N.
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AD, ELA2 mutation
Predictable cycles
Aphtous stomatitis
Tx: G-CSF, steroids
• Chediak-Higashi
Syndrome
– AR, LYST mutation
– Giant lysosomes,
ineffective granulopoiesis
– Oculocutaneous albinism
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
Spleen “Deficiency”
• Splenectomy
– 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 > spherocytosis > ITP > sepsis
• Infections
– S. Pneumoniae (mostly)
– Haemophilus, GNR,
Neisseria (less common)
T-Cell Deficiency
• DiGeorge’s
– 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
Food Safety
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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
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
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
Leprosy
Mycobacterium leprae
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Lepromatous 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
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Tuberculoid Leprosy
Strong TH1 response
Small # of bacteria
Self-limiting
Form granulomas
AIDS
HIV infection
• Lenti- retrovirus, persistent viremia, infects T-cells
and macrophages (CD4 + CCR5/CXCR4)
• CD4 >500 asymptomatic, 200-500 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.
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
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
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
Chlamydia
C. trachomatis, psittaci, pneumoniae
LGV (STD)
• Endemic in Africa/SE Asia/
India/S. America
• Painless ulcer (heals) to
lymphadenopathy (scars) to
ulceration of genetalia
• Tx: Doxycycline po bid x 21d
Urethritis
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NGU
7-14d incubation
Dysuria, scant discharge
Complications
– PID, ectopic pregnancy
– Reiter’s syndrome (arthritis)
Trichomonas Vaginalis
• Flagellated motile protozoa
• Yellow, purulent, frothy, foul-smelling vaginal
discharge, itch, dysuria, lower abd pain
• Tx: Metronidazole (ok in pregnancy)
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)
Herpes Simplex
HSV-1/2
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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
Syphilis
Treponema pallidum
• 1⁰ - localized painless chancres (ulcerated, nontender, 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
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
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
Donovanosis
Klebsiella granulomatis
• Painless destructive ulcers
• No lymphadenopathy
• Tx: Doxycycline (+aminoglycoside)
TORCH Syndrome
• Mother asymtomatic but baby has: small size,
hepatosplenomegaly, rash (thrombocytopenia),
CNS defects (encephalitis, seizures), jaundice
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Toxoplasma
Other (syphilis, HIV)
Rubella
CMV
HSV
TORCH Syndrome
Toxoplasmosis
• 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
Other (syphilis)
• 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
TORCH Syndrome
Other (HIV)
• Reduce transmission by
– Anti-HIV therapy (zidovudine)
during pregnancy and at birth
– Give infant antiretroviral
therapy for 16 weeks
– Cesarean delivery
– No breast feeding
Rubella
• Vaccinate mother
• Highest risk when mother
infected in 1st trimester, no
risk after 16 weeks
• Infected infant has patent
ductus arteriosus
TORCH Syndrome
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CMV
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
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HSV
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
Other Congenital
• GBS
– 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
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.
Endocarditis
NVE
• Native Valve Endocarditis
• Viridans strep most
common (followed by S.
aureus, Strep, Entero)
• If culture negative, can be
HACEK, intracellular
pathogens, fungi
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PVE
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
Endocarditis
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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
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
Respiratory Diseases
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Rhinitis
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
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Influenza
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
Respiratory Diseases
Typical Pneumonia
Streptococcus 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
Atypical Pneumonia
Mycoplasma pneumoniae
• 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
Respiratory Diseases
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Aspiration Pneumonia
Chronic, foul sputum
Polymicrobial anaerobic,
microaerophilic aspirated
into lung
Alcoholics, seizures,
tracheoesophageal fistula
are risk factors
Tx: Clindamycin PO x 3wks
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, 1850y 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 immunocompromised)
+ Dexamethasone
Acute Viral Meningitis
• Enterovirus
– Kids > 2 wks old
– Summer months
– Hand-foot-mouth
disease, herpangina
• HSV-2
– Aseptic meningitis
– Genital warts
• HIV
– Aseptic meningitis
• 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
Chronic Meningitis
• Fungal
– 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
Intracranial Abscess
• Frontal: sinus, teeth
• Neurologic deficit
Temporal: ear, jaw, sinus • 1-3d: early cerebritis
Cerebellum: ear, jaw
4-9d: late cerebritis
– Strep, GNR, Bacteroides,
10-13d: early capsule
S. aureus, Fusobacter
>14d: late capsule
• MCA: blood, lung, heart • Dx: MRI/CT c contrast
– Staph, Strep, Fusobacter,
• Tx: Surgical drainage,
Actinomyces, Anaerobes
manage ICP, culture
• Beneath wound
Metronidazole + ceph +
– Clostridium, Staph, Strep
naf/vanco
Viral Encephalitis
• Non-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
Subdural Empyema
• Bacteriology
– 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
Epidural Abscess
Intracranial
• Intracranial epidural abscess
spills over into subdural
space
• 81% associated with
subdural empyema, similar
bacteriology, diagnositic,
treatment
Spinal
• 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
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
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
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
UTIs
Lower UTI
• Cystitis
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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
Upper UTI
• Fever common symptom
• Pyelonephritis
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85% E. coli, 15% entero
Dysuria, frequency, urgency
Fever, CVA/flank tenderness, N/V
“urosepsis” appear septic
Tx ampi + aminoglycoside x 14d
• Renal Abscess
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Rare complication in DM
Can be caused by S. aureus
Dx CT/Ultrasound
Tx anti-staph PCN, cephalosporin
Other UTIs
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Catheter-related UTI
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
•
•
•
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Pregnancy
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
Cellulitis
Staph. aureus | Strep. pyogenes
• Source: anterior nares
• Source: nasopharynx
• Virulence: hemolytic
• Virulence: M-protein
toxin and leukocidin
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
Skin and Soft Tissue Diseases
Synergistic Gangrene
• Clostridium perfringens is
synergistic with GNR, S.
aureus causing cellulitis
• Necrosis of blood vessels,
gangrene of subcutaneous
tissue, spreads rapidly
• Tx: Surgical removal
Toxin-Cased Skin Inflammation
• 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
Skin and Soft Tissue Infections
•
•
•
•
Anthrax
Bacillus anthracis, a soil
bacterium
Marked edema, necrosis
surrounding black ulcer
20% fatal if untreated
Common in underdevelopd
world
•
•
•
•
Pasteurella Multocida
Gm- coccobacillus
Cat bites
Pain/swelling at bite can
spread to joints and bone
Tx: opening bite, cleaning,
PCN
Skin and Soft Tissue Infections
Lymphocutaneous Granulomas
• 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
Lyme Disease
• 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
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
Vibrios
• Vibrio cholerae
– 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
Pathogenic E. coil
• ETEC (-toxigenic)
– 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)
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
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
Helicobacter
• H. pylori
–
–
–
–
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
– Homosexual men
– Tx amp and/or gent