Presence of Infection

eye, ear, CNS barrier defense

- tears contain lysozyme - eyes are flushed constantly - ears/CNS separated by barriers - microglial cells or CNS macrophage

HA1C

- <7% if have DM - ~6.5% if don't have DM

urinary tract barrier defense

- urine is bactericidal - Tamm-Horsfall protein that binds bacteria - system is frequently flushed - vaginal lactobacilli produces an acidic env.

glucose

- as the immune response kicks in, glucose intolerance is common - fasting BG: 70-100 - post prandial BG: < 140

treat fever in whom?

- controversial - 38.6-39C or 103-104F - in young children, esp. those at risk of seizures - severe CV and pulmonary disease

fever of >40C or 106F

- drug fever - heat stroke - malignant hyperthermia/neuroleptic malignant syndrome

GI tract barrier defense

- gastric pH, pancreatic enzymes, bile salts - peristalsis and epithelial cell turnover - normal flora - peritoneal, splenic and hepatic macrophages

BP changes with infection

- hypotension - then hypertension as the body responds to stress and inflammation which can compromise renal function

pulse-temp dissociation

- increased temp and a normal pulse - or temp goes below 37C and the pulse goes up - in this case consider intracellular organisms or viral infections (with bacterial infections typically see increased temp and pulse)

WBC and differential

- know normal value (4,500 to 10,000 cells/mm3) - may not see response in elderly or pts post-chemo/transplant/rheum pts (may be lower than normal)

skin and membrane barrier defense

- lysozyme hydrolyzes the aa backbone of peptidoglycan - IgA blocks host cell receptor binding - iron binding proteins deprive the organism of iron

ALT

- most specific marker for liver damage - L = liver - ALT = SGPT

respiratory tract barrier defense

- mucous membrane - IgA - cough - alveolar macrophages and cilia - smoking impairs your alveolar macrophages and cilia and leads to chronic cough

ESR

- normal = 0-15mm/hour - nonspecific sign of inflammation (not diagnostic for disease)

CRP

- normal = <2 mg/dl - nonspecific sign of inflammation - used to monitor lipids

temp changes with infection

- normal is 37C or 98.6F - every degree C increase of a fever increases your O2 need by about 10%

fever

- oral temp >37.7C (99.9F) - rectal temp 0.4-0.6C higher than oral - peds and elderly generally have higher temps

HR changes with infection

- tachycardia - increased CO, followed by decreased CO if vasodilation persists - even angina, MI, CVA, or acute HF can be experienced during the infection sequelae

RR changes with infection

- tachypnea - breathing faster bc you are catabolic when you have an infection - decreased O2 saturation - hypoxia - fever increases oxygen consumption

8 factors immune response is based on

1. age 2. genetics 3. nutrition 4. current health status 5. past exposure 6. rest/sleep 7. stress level 8. barrier maintenance

purpose of a fever (2)

1. enhance inflammation, helps the immune function 2. inhibit microbial growth by creating an undesirable environment

6 steps to caring for the ID pt

1. establish the presence of an infection 2. attempt to identify the cause and source of the infection 3. select an appropriate empiric treatment regimen 4. monitor therapeutic efficacy, toxicity, pt. progress, lab trends 5. refine therapy, change therapy, definitive therapy, seek other causes 6. when to stop therapy? When to rethink #2, 3?

signs of an infection

1. fever/sweating 2. pain/inflammation/local tenderness/redness 3. chills 4. headache/stiff neck 5. diarrhea 6. burning on urination 7. cough/pus/sputum/discharge 8. SOB 9. malaise/weakness/fatigue 10. symptoms of glucose intolerance 11. poor appetite 12. loss of control of concomitant disease states

8 non-specific defense barriers

1. intact skin 2. mucous membranes and mucus production 3. cilia 4. peristalsis 5. coughing 6. micro flora 7. gastric pH 8. lysozyme production