Infectious Disease Emergencies

What is Systemic Inflammatory Response Syndrome (SIRS)

Describe the clinical manifestations that result from the systemic response to infection

What is the SIRs Criteria?

2 or more of the following:

◦ Body Temperature > 38°C (>100.4°F ) or temperature < 36°C (< 96.8°F )

◦ Heart rate > 90 beats/min

◦ Respiratory rate > 20 breaths/min or PaCO2 < 32 mmHg

◦ Peripheral WBC count > 12,000 or WBC < 4,000 or bandemia > 10% (band neutrophilia)

What drives the pathogenesis of sepsis?

The host, not the germ

How does sepsis start?

Focus of infection

Blood stream invasion - endotoxins and exotoxins released

Host releases humoral defense mechanisms

Severe sepsis is what?

Sepsis plus organ dysfunction

Septic shock is what?

Sepsis plus either hypotension or hyperlactatemia

What are the top 2 causes of sepsis?

Pneumonia and UTIs

What are the most common gram-positive isolates for sepsis?

S. aureus and S. pneumoniae

What are the most common gram-negative isolates for sepsis?

E. coli, Klebsiella, and Pseudomonas aeruginosa

What is the strongest predictor of mortality of sepsis?

Time to initiation of appropriate antibiotics

What is the empiric ABX for sepsis?

Vancomycin

When should you do sepsis workup?

Within 45 min of presentation, but should not delay administration of fluids or ABX

What is encephalitis?

Inflammation of the brain associated with evidence of neurologic dysfunction

What are the causes or encephalitis?

Herpes virus

Measles

Mumps

Rubella

Arboviruses (mostly mosquitoes)

Rabies

Toxoplasmosis

What does West Nile Virus cause?

Extreme lethargy

Flaccid paralysis

What is more significant of encephalitis rather than meningitis?

Movement disorders, ataxia, cranial nerve defects, exaggerated DTRs

How do you diagnose encephalitis?

Perform head CT before LP

What is the treatment of encephalitis?

Mostly supportive

Start acyclovir to cover HSV

What is the most common cause of sporadic fatal encephalitis?

HSV-1

What is meningitis?

Inflammation of the meninges resulting in meningeal symptoms

What is the most common cause of bacterial meningitis?

S. pneumoniae

Cornerstone of meningitis lab test?

CSF lumbar puncture

What does bacterial meningitis look like in CSF?

Glucose low

Protein heigh

>80% PMNs, 100-5000

What does viral meningitis look like in CSF?

Normal glucose, normal protein

10-100 lymphocytes

Most serious complication of meningitis?

Neisseria meningitidis

Most common clinical manifestation of Listeria monocytogenes?

Diarrhea

What is treatment of viral meningitis?

Self-limited, require supportive care

Is there a vaccine for meningitis?

Yes

Wha tis the most common cause of hospitalization for diabetics?

Diabetic Foot Infections

When should you consider osteomyelitis?

As a complication of any deep or extensive ulcer

◦ Diabetic foot ulcer, sacral decubitus ulcers

Non-healing ulcer after > 6 weeks of care and off-loading

Ulcer with visible or palpable bone

Unexplained high WBC count or inflammatory markers

How to diagnose osteomyelitis?

MRI of the bone

Most of the time, where is endocarditis located on the heart?

Mitral valve

Vegetations caused by what are at an increased risk?

S. aureus

What are signs and symptoms of endocarditis?

Petechiae or splinter hemorrhages

Janeway lesions

Osler nodes

Roth's spots

What is the diagnostic study for endocarditis (gold standard)?

Transesophageal (TEE)

Native valve endocarditis most commonly develops on what?

Mitral valve

IV drug use endocarditis most commonly involves what?

Tricuspid valve

What is the treatment for endocarditis?

Vancomycin

Which spine is more often involved in spinal epidural abscess?

Thoracolumbar more often than cervical spine

What are the progression of symptoms in spinal epidural abscess?

Nerve root pain, shooting or electric shocks

What is the treatment for spinal epidural abscess?

Vancomycin

Most of the time, what is necrotizing fasciitis?

Invasive group A Streptococcus infections

What is type I necrotizing fasciitis?

Polymicrobial infection

What is type II necrotizing fasciitis?

Group A streptococcal infection

What are necrotizing fasciitis indicators?

◦ Presence of purple or red bullous lesions

◦ Pain on palpation (and out of proportion) over contiguous but superficially unaffected area

◦ Indistinct margins

◦ Presence of crepitus

◦ Loss of sensation distal to the affected area

◦ Rapid progression

What is the treatment of necrotizing fasciitis?

Emergent Surgical Debridement