ID Emergencies

Question 1

Meningitis

1. Meninges are made up of what? 3
2. Meningitis affects which parts of the brain? 3

Answer 1

1. Meninges is made up of the
   - pia,
   - arachnoid
   - dura maters
2. Meningitis affects the
   - arachnoid,
   - subarachnoid space and
   - CSF

Question 2

Etiology for meningitis

1. MC bacterial causes? 3
2. MC viral causes? 6
3. MC fungal causes? 1
4. MC noninfectious causes? 5

Answer 2

1. Bacterial
   - Streptococcus pneumoniae
   - Neisseria meningitidis
   - Haemophilis influenzae
2. Viral
   - Enteroviruses,
   - HSV,
   - HIV,
   - West Nile,
   - VZV,
   - mumps
3. Fungal
   - Cryptococcus (most common)
4. Noninfectious
   - Tumor,
   - trauma,
   - brain abscess,
   - subdural empyema,
   - pharmacologic reaction

Question 3

Can be community acquired or healthcare associated

1. Community acquired? 4
2. Healthcare associated? 2

Answer 3

1. Community acquired
   - Streptococcus pneumoniae
   - Neisseria meningitidis
   - Haemophilis influenzae
   - Listeria monocytogenes (immune compromised)
2. Healthcare associated
   - Staphlococci and
   - aerobic gram negative bacilli

Question 4

Meningitis symptoms

1. Onset?
2. Classic triad?
3. Other symptoms? 7
4. Median duration of symptoms before presentation?
5. What is petechial rash associated with?

Answer 4

1. Abrupt onset
2. Classic triad:
   - fever,
   - nuchal rigidity,
   - change in mental status
3. -Intense headache
   Other symptoms:
   -photophobia,
   -lethargy,
   -nausea,
   -vomiting,
   -joint pain,
   -seizures
4. Median duration of symptoms before presentation 24 h (bacterial)
5. Petechial rash is associated with N. Meningitidis

Question 5

Diagnosing CNS infections in the elderly

1. Difficult to initially separate meningitis from what?
2. Both present with what?
3. Elderly with meningitis are less likely to have what symptom?
4. Any infection can cause what in the elderly?
5. Red flags? 5

Answer 5

1. encephalitis
2. both present with mental status changes
3. elderly with meningitis less likely to have fever
4. Any infection can cause delirium in the elderly
5. Red flags:
   - Behavioral changes/personality changes
   - Seizures
   - Lack of other source of infection
   - Headache, nuchal rigidity, exposure to infected persons
   - Low threshold to do LP

Question 6

Who needs a head CT prior to LP?

Proceed to head CT prior to LP if any of the following are present at baseline:
4

Answer 6

1. Immunocompromised
2. History of seizure within one week prior to presentation
3. Any of the following neurologic abnormalitie
4. Mandatory in patients with possible focal infection

Question 7

Who needs a head CT before the LP: Any of the following neurologic abnormalities? 5

Answer 7

1. Abnormal level of consciousness
2. History of CNS disease (mass lesion, stroke, or focal infection)
3. Papilledema
4. Abnormal level of consciousness
5. Focal neurologic deficit

Question 8

Lumbar puncture in meningitis
1. Any evidence of papilledema or focal neuro findings, DO NOT perform LP before you get a STAT CT to rule out what?

2. Perform LP immediately in the absense of what? 2

Answer 8

1. significant ICP (or herniation of brainstem may occur during LP)
2. • Papilledema
   • Focal neuro findings

Question 9

Meningitis work up

5

Answer 9

1. Blood cultures, CBC, and Chem 7
2. Send CSF to lab for cell count, gram stain, culture, glucose and total protein
3. As soon as LP is completed (before labs are even back) give 2 G Rocephin (Ceftriaxone) IV
4. All are admitted and Rocephin is continued at 2G IV q12h
5. Many even with proper, rapid treatment will die or have permanent CNS deficits

Question 10

Send CSF to lab for cell count, gram stain, culture, glucose and total protein

1. Any what on gram stain is diagnostic?
2. What WBC count is diagnostic for meningitis?
3. CSF glucose less than what is suggestive?

Answer 10

1. ANY (+) Gram stain is diagnostic
2. WBC in CSF > 1000 if PMNs make up 85% is diagnostic
3. CSF glucose less than 50% of serum glucose is suggestive

Question 11

CSF Normal Values

1. Pressure?
2. Appearance?
3. CSF total protein?
4. CSF glucose?
5. CSF cell count?
6. Chloride?

Answer 11

1. Pressure: 70 - 180 mm H20
2. Appearance: clear, colorless
3. CSF total protein: 15-45 mg/100 mL
4. CSF glucose: 50-80 mg/100 mL (or greater than 2/3 of blood sugar level)
   5, CSF cell count: 0-5 white blood cells (all mononuclear), and no red blood cells
5. Chloride: 110-125 mEq/L

Question 12

Pediatrics:

1. Bacterial meningitis occurs more frequently between age?
2. Uncommon to develop meningitis from OM and spread is not from direct extension but from what?
3. What may be the only clues in young infants? 2
4. Paradoxical irritability is suggestive of meningitis. What is this?

Answer 12

1. 2 months-2 years
2. systemic spread
3. • Irritability
   • poor feeding
4. (crying worsens when being held)

Question 13

Most common meningitis etiologic agents in pediatrics

1. MC? 3
2. In neonates?
3. Primary prevention of meningitis? 3

Answer 13

1. • Streptococcus pneumoniae (pneumococcus)
   • Neisseria meningitidis (meningococcus)
   • H. influenzae Type B (due to the vaccine now is a rare cause but used to be the most common)
2. In neonates consider gram – causes and Group B Strep
3. Primary prevention of meningitis
   - S. pneumoniae vaccine
   - H. influenzae vaccine
   - Meningococcal vaccine is available for adolescents and adults

Question 14

What are the following lab values for the normal CSF fluid:

1. White cells?
2. % neutrophils?
3. CSF Glucose?
4. Blood glucose?
5. Protein?

Answer 14

1. 5
2. 1%
3. 65
4. 85
5. 21

Normal. The normal number of WBCs in the CSF depends upon the age of the patient. The younger and more immature the infant is, the high the value is. CSF glucose vale depends upon the value of glucose in the blood and upon the integrity of the blood brain barrier. In pts with normal meninges the CSF value is usually about 75% of the blood level. When the meninges become inflamed, the active transport of glucose across the blood brain barrier becomes altered an dthe ratio drops proportionately to the degree of inflammation. Most viral meningitis produce less chanes than bacterial meningitis accordingly CSF glucose values are lower in bacterial meningitis.

Question 15

What does the following LP suggest?

1. White cells- 1243?
2. % neutrophils-94%?
3. CSF Glucose- 23?
4. Blood glucose- 78?
5. Protein-62

Answer 15

Bacterial Meningitis

Bacterial. Cases of early viral meningitis can present with an increased number of cells and neutrophils but usually the CSF glucose is normal or not lower than 40% of serum glucose.

Question 16

What does the following LP suggest?

WBC-250
% neutrophils- 86%
CSF Glucose- 47
Blood glucose- 90
Protein- 49

Answer 16

Fungal meningitis?

CSF is inconclusive. The high percentage of neutrophils indicates that bacterial meningitis is possible. It would be wise to administer abx until more information can be obtained. The gram stain result will be helpful. If it is positive for organisms, then this indicates bacterial meningitis. If the gram stain is negative, bacterial meningitis still cannot be totally ruled out. The child’s clinical condition is not part of this table, but in reality, a child who is alert, active and playful is more likely to have viral meningitis, as opposed to a lethergic, toxic child who is more likely to have bacterial meningitis. This will probably turn out to be a case of viral meningitis despite the high percentage of neutrophils, since an early viral meningitis will often have high neutrophil percentages. A repeat LP 12-24 hours from the first LP will be helpful. A repeat LP which demonstrates a clear shift toward mononuclear cells, is consistent with viral meningitis, while no shift, or only a slight shift would suggest bacterial meningitis.

Question 17

What does the following LP suggest?

WBC-190
% neutrophils- 60%
CSF Glucose- 50
Blood glucose- 87
Protein- 48

Answer 17

Viral meningitis

Viral. Most cases of viral meningitis will present with a moderate increase in the number of white cells and a % of neutrophils not higher than 60-70%.

Question 18

What is Menigoencephalitis?

Answer 18

Overlap of menigitis + encephalitis

Question 19

Encephalitis

1. What is it?
2. Most commonly caused by?
3. Which viruses in particular are rapidly progresses and life threatening? 2
4. Other causes? 4

Answer 19

1. Inflammation of the brain
2. Most commonly caused by viral infections
3. HSV-1 and HSV-2 are rapidly progressing and life threatening
4. • West Nile Virus,
   • CMV,
   • Mumps,
   • EBV

Question 20

The difference between meningitis and encephalitis?

Answer 20

Encephalitis has altered brain function and neurologic findings like personality changes, paralysis, hallucinations, altered smell, problems with speech etc.

Question 21

Symptoms of encephalitis
1. Mild cases may just have what?

2. Severe cases? 10
3. Children? 6

Answer 21

1. Mild cases may just have flu like symptoms
2. Severe cases
   - Severe HA,
   - fever,
   - altered consciousness,
   - confusion, agitation, personality changes,
   - seizures,
   - loss of sensation, paralysis, muscle weakness,
   - hallucinations, double vision,
   - perception of foul smells,
   - problems with speech or hearing,
   - LOC

Children:

• bulging of fontanels,
• nausea, vomiting,
• body stiffness,
• inconsolable crying,
• crying that worsens when picked up,
• poor feeding

Question 22

Work up and treatment of encephalitis

Work up? 4

Treatment?

Answer 22

1. CT and/or MRI of head
2. CBC,
3. CMP
4. LP

Acyclovir 10mg/kg IV q 8 h (empiric treatment for HSV as it is the most deadly)

Question 23

What are you looking for when you get an for LP? 4

Answer 23

1. the usual cultures etc., but also
2. PCR for HSV1,
3. serology: IgM ab for West Nile virus, mumps, EBV
4. Note if RBCs in CSF and nontraumatic tap it is HSV until proven otherwise

Question 24

Septic Arthritis
Septic arthritis is a medical emergency!
1. When left untreated, it can destroy a joint in what time?
2. What pattern does it present?
3. More commonly affects large joints, especially ______?
4. Signs and Symptoms? 3

5. What MUST you do in this pt?

Answer 24

1. 12-24 HOURS
2. Usually affects only one or a few asymmetrical joints
3. knee
4. • Acute or subacute onset of pain
   • Erythema, swelling, and limited joint motion
   • Systemic sx (fever, malaise, etc) may be present or absent
5. You must do an arthrocentesis on any – red, hot, swollen joint

Question 25

Septic Arthritis 1. Joint fluid analysis shows what level of RBC? 2. Send joint fluid for ? 4 3. Gram stain of joint fluid will show the causative organism in most cases EXCEPT what? 4. If GC arthritis is suspected in sexually active patient, do what? 3 5. Tx? - No indication for what?

Answer 25

1. >40,000 WBCs in most cases 2. - crystals, - glucose, - cell count, - culture (and specify CULTURE + SENSITIVITY + R/O GONORRHEA) 3. gonococcal arthritis (75-80% are false negative) 4. - cervical, - urethral, or - rectal GC cultures as appropriate for >90% sensitivity 5. Treatment is high-dose IV antibiotics - No indication for intra-articular antibiotics CDC website is best source for latest antibiotic recommendations

Question 26

Bacteremia 1. Symptoms? 7 2. Source of infection? 7

Answer 26

1. Symptoms: - fever, +/- chills, - rigors may suggest bacteremia, - disorientation, - hypotension, - respiratory failure, - sepsis, septic shock, - skin lesions 2. Source of infection: - respiratory tract, - central venous catheters, - urinary tract, - GI tract, - biliary tract, - skin, - soft tissues

Question 27

Bacteremia 1. Gram stain: 25-50% of all blood stream infections? 2. Treatment for severe sepsis +/- shock? 3

Answer 27

1. Gram – 2. Treatment for severe sepsis +/- shock - Gentamicin or tobramycin or amikacin - PLUS antipseudomonal cephalosporin like Cefepime - (+/-) vancomycin until cultures come back

Question 28

``` Bacteremia Gram + 1. Leading cause? 2. Empiric tx? 3. MSSA tx? 4 4. MRSA tx? 2 ``` 5. Work up should include what?

Answer 28

1. Staphlococcus aureus is a leading cause of Gram + bacteremia 2. Empiric treatment - vancomycin 3. MSSA – PCN, nafcillin or oxacillin, vanco 4. MRSA – vancomycin or daptomycin 5. Work up should include transesophageal echo to rule out infective endocarditis

Question 29

Sepsis/Septicemia 1. Clinical syndrome from what kind of response to an infection? 2. Definition of sepsis = ? 3. General symptoms: 6

Answer 29

1. dysregulated inflammatory 2. infection + some of the following: 3. - Temp > 38.3 or less than 36 - HR > 90 - RR >20 - altered mental status - significant edema - hyperglycemia without a hx of DM glucose > 140

Question 30

Definition of sepsis = infection + some of the following: 1. Inflammatory? 4 2. Hemodynamic? 2 3. Other monitoring parameters? 4

Answer 30

1. Inflammatory: - WBC >12K or less than 4K, - WBC with > 10% immature forms, - elevated CRP, - elevated procalcitonin 2. Hemodynamic: - Hypotension, - often with a wide pulse pressure 3. - Poor urine output, - elevated creatinine, - elevated INR and PTT, - low platelets

Question 31

Definition of sepsis continued Definition of sepsis = infection + some of the following: 1. GI? 3 2. CV? 2 3. TX?

Answer 31

1. - Ileus, - elevated bilirubin, - elevated lactate, 2. - decreased capillary refill, - arterial hypoxemia 3. Treatment: Supportive and treat most likely source of infection same as bacteremia

Question 32

Cellulitis | Superficial soft tissue infections are rarely emergencies with 3 exceptions?

Answer 32

1. Infection around the face and hand 2. Cellulitis in the presence of diabetes or PVD 3. Local infection with the presence of leukemia or HIV

Question 33

What is the definition of cellulitis?

Answer 33

Cellulitis: Acute spreading infection of the skin to and through the dermis

Question 34

ALL cellulitis, folliculitis, furnuculosis is due to 1.______ until proven otherwise. 2. DOC is _________? 3. Alternate=_________?

Answer 34

1. MRSA 2. BACTRIM 3. Clindamycin

Question 35

1. Impetigo: What is it? 2. Small vesicles which quickly rupture and form what? 3. Tx?

Answer 35

1. Superficial skin infection usually seen in kids due primarily to Strep, uncommonly Staph 2. “honey-colored” crusts 3. Bactroban

Question 36

1. What is Endocarditis? 2. May present in which two ways? 3. Patients at high risk? 3 4. Subacute may present how? 3 5. acutely the may preent in? 3

Answer 36

1. Infection of the endothelial surface of the heart, most often the valves - This is a TOUGH ED diagnosis to make but tougher if you miss it 2. May present as acute or subacute 3. Patients at high risk are those with - previous valve damage, - valve replacement or - history of IV drug use 4. Subacute may present with - anorexia, - night sweats - weight loss 5. Acutely they may present in - cardiac failure, - stroke due to septic emboli, - or cold extremity due to septic emboli

Question 37

Endocarditis: 1. In IV drug abusers may involve which valve and present with what? 2. OFTEN _______ murmur can be detected 3. Characteristic (but NOT specific) cutaneous lesions:? 4 4. Dilated eye exam may show what?

Answer 37

1. tricuspid valve and they may present with bilateral embolic pneumonia 2. no (R) sided 3. - Conjunctival and palatal petechiae - Subungual (splinter) hemorrhages - Osler nodes = tender, erythematous nodules with opaque centers which appear on pulp of fingers/toes - Janeway lesions = Nontender red or maroon macules or nodules on the palms and soles 4. Roth spots (pale oval areas surrounded by hemorrhage) near optic disc

Question 38

Endocarditis diagnostics 1. Echocardiogram may show what? 2. Which is more sensitive: TTE or TEE? 3. What blood dyscrasia may be present? 4. What is almost always present but NOT specific? Obtain blood cultures and start empiric antibiotics based on latest CDC recommendation

Answer 38

1. valvular vegetation 2. TEE is more sensitive than TTE 3. Normocytic, normochromic anemia 4. Elevated ESR