ID: SHAEER PACKET (PART I - INTRODUCTION)

Host defenses against infection? (four)

1. Physical

2. Chemical

3. Normal flora

4. Immune system

Normal gram positive cocci flora of the skin? (two)

1. Staph spp. (CoNS, S. aureus)

2. Streptococcus spp.

Normal gram positive rods flora of the skin? (two)

1. Corynebacterium spp.

2. Cutibacterium spp.

Normal gram negative rods flora of the skin? (one)

1. Acinetobacter spp.

Normal gram positive cocci flora of the oral cavity? (three)

1. Streptococcus spp.

2. Micrococcus spp.

3. Peptostreptococcus spp.

Normal gram positive rods flora of the oral cavity? (two)

1. Actinomyces spp.

2. Corynebacterium spp.

Normal gram negative cocci flora of the oral cavity? (one)

1. Neisseria spp.

Normal gram negative rods flora of the oral cavity? (two)

1. Haemophilus spp.

2. Bacteroides (non-fragilis)

Normal gram positive cocci flora of the upper respiratory tract? (two)

1. Staph spp.

2. Strep spp.

Normal gram negative cocci flora of the upper respiratory tract? (one)

1. Neisseria spp.

Normal gram negative rods flora of the upper respiratory tract? (two)

1. Haemophilus spp.

2. Bacteroides spp. (non-fragilis)

T/F: Candida spp. are normal flora of the upper respiratory tract.

True

Normal gram positive cocci flora of the GI tract? (two)

1. Enterococcus spp.

2. Peptostreptococcus spp.

Normal gram positive rods flora of the GI tract?

1. Clostridium spp.

2. Lactobacillus spp.

Normal gram negative rods flora of the GI tract? (four)

1. Enterobacterales (E. coli, Klebsiella Spp.)

2. Fusobacterium spp.

3. Bacteroides spp. (B. fragilis)

T/F: Candida spp. are normal flora of the GI tract.

True

Normal gram positive cocci flora of the genital tract? (two)

1. Staph. spp.

2. Strep. spp.

Normal gram positive rods flora of the genital tract? (two)

1. Corynebacterium spp.

2. Lactobacillus spp.

Normal gram negative rods of the genital tract? (three)

1. Enterobacterales spp

2. Prevatella spp.

3. Bacteroides spp. (includes B. fragilis)

T/F: Mycoplasma and Candida spp. are normal flora of the genital tract.

True

Mature neutrophils are known as _______

A. Segs

B. Bands

A. Segs

Immature neutrophils are known as ________

A. Segs

B. Bands

B. Bands

What does it mean when a neutrophil test exhibits a "left-shift?"

Increase in seg neutrophil consumption secondary to an infection/inflammation

In what patient types can a neutrophil left-shift effect be blunted? (two)

Neutropenic patients

Elderly patients

Basophils are associated with type ____ hypersensitivity, which is immunoglobulin _____ mediated.

type I hypersensitivity, IgE mediated

T/F: Eosinophils are associated with allergic reactions or parasitic infections.

True

Monocytes/macrophages are associated with what two disease states?

Tuberculosis

Lymphoma

Role of T lymphocytes?

Cellular immunity against viruses and tumors (regulates immune system)

Role of B lymphocytes?

Antibody production; antigen presenting cells

3 acute phase reactant tests?

1. Erythrocyte sedimentation rate (ESR)

2. C-reactive protein (CRP)

3. Procalcitonin (PCT)

Describe the erythrocyte sedimentation rate (ESR) test

Measures rate that RBCs settle in a tube that may suggest infectious/inflammatory disease

Erythrocyte sedimentation rate (ESR) can be affected by what three types of infections?

1. Endocarditis

2. Osteomyelitis

3. Pyelonephritis

Erythrocyte sedimentation rate (ESR) is ________ in patients with anemia. (increased, decreased)

Increased

Erythrocyte sedimentation rate (ESR) is ________ in patients with polycythemia. (increased, decreased)

Decreased

Erythrocyte sedimentation rate (ESR) is ________ in patients who have received IVIG. (increased, decreased)

Increased

Describe C-reactive protein (CRP) test

CRP is elevated during inflammatory process, but it is nonspecific

Usually useful for tracking response to acute infections

Describe Procalcitonin (PCT) test

PCT is a peptide precursor produced by thyroid during calcitonin synthesis (levels usually low in serum)

In infection, PCT is produced via alternative pathways in various tissues

Pros of Procalcitonin (PCT) test (three)

1. More specific marker for bacterial infections than either CRP or ESR

2. Can be used to assess mortality risk of patients with infections and determining when to initiate antibiotics in respiratory tract infections

3. Aid decision to d/c antibiotics used empirically in possibly infected patients and in patients recovering from infections

Cons of Procalcitonin (PCT) test (two)

1. Low/normal level if localized bacterial infections or drawn too early in the course of an infection

2. False elevations with severe physiologic stress, certain malignancies, ESRD, and some immunomodulatory medications

PCT level of < 0.25 ng/mL (mcg/L) indicates...

Low infection risk, helps justify antibiotic discontinuation

PCT level of > 0.5 ng/mL (mcg/L) indicates...

Continue antibiotics

How frequently should we recheck PCT in patients with pneumonia/sepsis?

Every 1-2 days to monitor resolution; if PCT reduces by 80-90% or decreases to

Define colonization

Presence of organisms at a site that does not cause disease

Sterile body sites? (eleven)

1. Bloodstream

2. Bone

3. CSF

4. Lower bronchi/lungs

5. Lower/middle ear

6. Organs (liver, kidney, uterus, ureters)

7. Peritoneal fluid

8. Pericardial fluid

9. Pleural cavity

10. Sinuses

11. Synovial fluid (joints)

Indications of infection? (eight)

1. Increase/decrease in WBCs w/ or w/o left shift

2. Increase in WBCs at site of infection

3. Presence of pathogens on gram stain +/- culture

4. Presence of pathogens on gram stain +/- culture

5. Increase in ESR, CRP

6. Localized s/sx: cough, erythema, inflammation, increased sputum production, pain, purulent discharge, swelling, tenderness

7. Systemic s/sx: chills/rigors, hypo or hyperthermia, hypotension, AMS, tachycardia, tachypnea

8. Radiographic: CT, MRI, ultrasound, X-ray

Drugs which can cause leukocytosis? (three types)

1. Corticosteroids

2. Lithium

3. B-agonists

Common causes of fever? (ten)

1. Infection

2. Drugs

3. Seizures

4. Post-operative

5. Thromboembolic disease

6. Hematoma

7. Intracranial hemorrhage

8. Malignancy

9. Autoimmune disorder

10. Transplant rejection