CPC

1
CPC 2Fever, cough, dyspnea, and change in
mental status

• Barbara J. Crain, M.D., Ph.D.
• October 7, 2008

2
Heart

• Borderline cardiomegaly
• Hypertensive changes
• Heart weight 460 gm
  for height
  229399 gm
  for weight 241-481 gm
• Occasional boxcar nuclei
• Mild to moderate coronary
  atherosclerosis

3
Kidney

• Nephrosclerosis
• Arteriolosclerosis
• Hypertensive changes

4
Brain (striatum)
Dilated perivascular spaces
Arteriolosclerosis
Perivascular hemosiderin
Hypertensive changes in blood vessels
5
Brain (deep cortical white matter)
Normal white matter (HE)
Normal astrocytes (GFAP)
Reactive astrocytes (GFAP)
Focal pallor and reactive astrocytosis, most
likely hypertensive in origin
6
Liver

• Mild acute congestion
• Mild macrosteatosis
• Mild nonspecific
  inflammation of triads
• No evidence of fibrosis,
  cirrhosis, or alcoholic
  
  hepatitis

7
Lungs gross examination

• Small pleural effusions
• Markedly increased weight 2,900 gm
  (reference 685 1,050 gm)
  
• Firm, red parenchyma, most marked in right lung
• 2-cm cavitary lesion in right upper lobe
• Gross impression severe bronchopneumonia with
  abscess

8
Lung abscesses
9
Lung with congestion and hemorrhage
10
Lung with hemorrhage, necrosis
11
Lung with hemorrhage, necrosis
12
Lung with hemorrhage, necrosis and bacteria
pneumonia in leukopenic patient
13
Gram-positive cocci
14
Gram-positive cocci
??
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ococcus-aureus.jpg
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argets/images/pho/t028/T028362A.jpg
15
Blood culture from night of admission

• ORG 1 METHICILLIN RESISTANT STAPHYLOCOCCUS
  AUREUS IN ANAEROBIC BOTTLE
• ---------------------------------------------
  -----------------
• RESULT
• ANTIBIOTIC MIC (mcg/ml)
  INTERPRETATION
• Oxacillin ------------- gt2
  -------------- Resistant
• Vancomycin ------------- 2
  ------------ Susceptible
• Staphylococcal isolates that are resistant
  to oxacillin (MRS) should
• not be treated with penicillins,
  beta-lactam/beta-lactamase inhibitor
• combinations, cephalosporins and carbapenems.

16
Sputum culture

• 1. BACT MICRO EXAM
• TYPE 2 - ADEQUATE SPECIMEN. MANY
  POLYMORPHONUCLEAR CELLS AND MANY SQUAMOUS
  EPITHELIAL CELLS. MANY NORMAL UPPER RESPIRATORY
  FLORA
• 2. BACTERIOLOGY CULTURE
• MODERATE MIXED RESPIRATORY FLORA AT 1 DAY
• POSITIVE AT 1 DAY
• ORG 1 HEAVY METHICILLIN RESISTANT
  STAPHYLOCOCCUS AUREUS

17
Major autopsy findings

• Severe hemorrhagic and necrotizing
  bronchopneumonia with abscess formation, right gt
  left
• Culture-positive for MRSA
• Chronic changes associated with hypertension
• Borderline cardiomegaly
• Arteriolonephrosclerosis of kidneys
• Hypertensive cerebral vascular disease
• Focal chronic white matter damage
• Mild to moderate coronary atherosclerosis

18
Cause of death

• Part I
• Sepsis (due to or as a consequence of)
• Acute MRSA bronchopneumonia with abscess
  formation
• Part II
• Atherosclerotic vascular disease
• Hypertension
• Cardiomegaly
• History of smoking

19
Hospital-acquired MRSA infections

• First described in 1960, increasing problem in
  1980s
• MSSA vs. MRSA includes a large genetic element
  staphylococcal cassette chromosome mec (SCCmec)
• SCCmec carries the mec gene complex and various
  resistance genes against non ß-lactam antibiotics
• Over half the Staph isolates in some hospitals
  are now MRSA
• Infections often in very ill patients,
  particularly in ICUs
• Bacteremia, pneumonia, endocarditis
• High morbidity and mortality

Clin Infect Dis 2008 46S344-49 Brit J Anaesth
200492121-130
20
Community-acquired MRSA infections

• More often children and young adults without
  underlying illnesses
• Generally skin / soft tissue infections
  (cellulitis, abscess)
• Emerging problems necrotizing fasciitis,
  Waterhouse-Friedrichsen syndrome, empyema,
  necrotizing pneumonia
• Person-to-person transmission
• Strains causing CA-MRSA going back into hospitals

http//www.jems.com/Images/mrsa_tcm16-33808.jpg
21
Community-acquired MRSA pneumonia

• Rapidly progressive necrotizing pneumonia
• Effusions, bacteremia common
• Primarily children, young adults
• High mortality rate
  (gt50 in some series)
• Median survival time 4-7 days
• Often preceded by viral-like illness
  (particularly influenza A)

Emerg Infect Dis 200612498-500 MMWR
200756?14)325-329 Ann Clin Microb Antimicrob
200871
22
Pathogenesis of CA-MRSA

• Well characterized strains USA300 most common
  in US
• Basis for apparent increased virulence
• Increased fitness of bug?
• Improved evasion of host immune system?
• Unique toxin production?
• Panton-Valentine leukocidin (PVL) gene toxin
  with leukocytolytic and dermonecrotic activity

Clin Infect Dis 2008 46S350-5 http//a.abcnews.c
om/images/Health/ld_mrsa_080425_mn.jpg9
23
Prevention of MRSA
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ing.jpg
24
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ing.jpg