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Exam Prep?

Infectious Diseases

A Balancing Act

Ehrlichia

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SARS SARS Infiltrate

Bioterrorism Category ACategory A

Cholera Cot Hantavirus

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Viral Diseases

By far the most common

Direct killing Autoimmune Tumor transformation

Chlamydia

Intracellular Almost bacteria Common Many forms of disease Direct cell death Autoimmune

Bacterial

Aerobic & anaerobic Gram +/- Direct killing Toxins Autoimmune Altered body

substances

Fungi

Some are biphasic Yeast or hyphal

Challenge to immune system

Systemic vs. Cutaneous infections

Direct killing Autoimmune

(cell mediated)

Protoza

Numerous One of the most

common causes of death world-wide.

Habitat modification Complex life cycle

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Helminthes

Complex life cycle Intestinal Tissue Seizures in Mexico

A Balancing Act Host Factors

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Tears

Immune System

Charles Lutwidge Dodgson

Lewis Carroll January 27 1832 January 14 1898

Mathematician Alice Liddell Alice's Adventures in

Wonderland, 1865 Through the Looking-Glass and

what Alice found there, 1872 The Hunting of the Snark, 1876

Human Microbe, Co-Evolution

Coevolution also means coextinction.

Differences in replication rate.

Keep ‘evolving’ just to stay in the game. Red Queen hypothesis Red Queen dynamics Through the Looking Glass

Population specific Human Bug

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A Balancing Act

No spitting in the street.

Actually fined in most towns.

Organisms resistant to drying

M. tuberculosis Vectors

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Essay Scenario

Cytopathic Effect

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Rhinovirus

Influenza A Bacterial Pneumonia H1N1

Pandemic of 1918

Spanish flu of 1918 World-wide pandemic At least 26 million died

One Twin-Towers Every day For 24 continuous years US deaths 700,000

US Population 1918

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US Population 1918

Measles (rubeola) Measles Giant Cells

Mumps Polio

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Polio Rotovirus

Hemorrhagic Fevers

Herpes

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CMV Varicella-Zoster

Varicella-Zoster Varicella-Zoster

Varicella-Zoster

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Hepatitis B Chronic Hepatitis B

EBV HPV Cervical and vulvar

cancers Very disturbed epi

maturation

Staphylococcal Infections

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Pneumonia with abscess

Streptococcal erysipelas

Pneumonia Rheumatic Fever

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Acute Glomerulonephritis C. diphtheriae

C. diphtheriae Diphtheria

GC

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Neisseria meningtidis Haemophilus Influenza

B. pertussis

Listen to the cough.

Hurricane Isabel Approaches a Tanker

SalmonellaShigella

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Cholera

Helicobacter

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Tuberculosis

Mycobacterium tuberculosis (most cases) Type IV hypersensitivity Granuloma

Primary infection Pulmonary Perhaps goes lymphatics Hopefully it stops here.

Secondary TB Internal reactivation Perhaps years later Not all patients

Tuberculosis Tuberculosis

Ghon Lesion Ghon Complex

Tuberculosis

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Skin Test

PPD Injected intradermally Read in 2 days Measure swelling

Not redness

Positivity maybe life long

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Miliary Spread of TB Leprosy

Disease in History

“If your hand causes you to stumble, cut it off. It is better for you to enter life maimed than to have two hands and go to Gehenna to the unquenchable fire.

And if your foot causes you to stumble, cut it off; for it is better for you to enter life lame than to have two feet and be thrown into Gehenna.

And if your eye causes you to stumble, tear it out; for it is better for you to come into the Reign of God with one eye than to have two eyes and be thrown into Gehenna – where their worm never dies, and the fire is never quenched.”

Mark 9

Syphilis

Syphilis

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Lyme Disease

Lyme Disease

Clostridial infections

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Gas Gangrene

Chlamydia Reiter Syndrome

Arthritis Non-GC urethritis or

cervicitis Chlamydia Shigella, Salmonella…

Conjunctivitis Men in their 20’s HLA-B27 (80% +) Autoimmune with infectious

trigger Low back stiffness and pain.

Reiter Syndrome

HLA B27 Yong men Chlamydia Symptoms may

regress, but 50% have recurring

problems

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Rickettsial DiseaseMore Rocky Mountain Spotted Fever

Typhus

Allergic reactions to fungi Histoplasmosis

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Pseudomonas

Candidiasis Candida Esophagitis

Cryptococcosis Aspergillus

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Mucomyocsis Pneumocystis Pneumonia (PCP)

Malaria

Malaria Malaria

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Cerebral Malaria Leishmaniasis

Leishmaniasis Giardia

AmebiasisAlpha Hall

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Trichinella Worms

T. solium T. solium

Cysticercosis

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Schistosomiasis

Onchocercerciasis

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“Cavitary”, Be careful What You Say

TB Pericarditis Slide 78

Reading the PPD

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Miliary Spread of TB

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Opisthotonus

Strabismus CSF Analysis Always look for papilledema

first! CSF pressure Color and clarity Sp. Gravity Protein Glucose (2/3 of blood) Cells

PMNs Lymphs Others

Gram stain Culture

Lymphangitis

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Strep

Tissue planes Lymphangitis Rapid spread Aggressive types