Staphylococcal Infection

1
Staphylococcal Infection
2
Bacteriology
3
Bacteriology

• Gm ve cocci
• Cluster
• Facultative
• Nonfastidious

4
Classification

5
Classification

• Staph. Aureus
• Coagulase positive
• Staph. Epidermidis
• Coagulase negative

6
Staph. Aureus Infections

• Mechanism of pathogenesis
• 1-coenzymes local destruction
• 2-Secretion of Toxins
• 3-Superantigens activating T cell receptors
• 4-Interfer with opsonophagocytosis

7
Epidemiology

• Normal human flora nose moist areas
• Transmission Hands/nose sec/contact/rarely
• air.
• Colonize skin, newborn nasoph umb.
• Invasion Skin breaks, I/V access, immune defect,
  steroids and neutropenea.

8
Clinical conditions
9
Clinical conditions

• Suppurative.
• Toxic related

10
Clinical conditions

• Suppurative.
• Toxic related
• Scalded Skin Syndrome SSS
• Toxic Shock Syndrome
• ??Kawasaki Disease
• Food poisoning

11
Skin

• Foliculitis
• Furaculosis (Boils)/Carbunkles
• Emptigo contagoesa
• Bullous Emptigo
• SSS (Ritter disease)

12
(No Transcript)
13
(No Transcript)
14
(No Transcript)
15
(No Transcript)
16
(No Transcript)
17
(No Transcript)
18
(No Transcript)
19
(No Transcript)
20
(No Transcript)
21
Respiratory Infections

• Sinusitis
• Parotitis
• Cervical adenitis
• Tracheitis compared to croup
• Pnumonia

22
(No Transcript)
23
(No Transcript)
24
(No Transcript)
25
Sepsis

• Start as focal lesion e.g. a boil
• Yield to septicemia
• Localize to organs e.g. lung, bone, heart, brain
  etc

26
(No Transcript)
27
(No Transcript)
28
Muscles/Bone/Joints

• Tropical pyomyositis
• Localized abscesses and high CPK
• Osteomylitis
• Trauma/Sx, pain, fever
• Septic arthritis
• Usually hematogenous

29
(No Transcript)
30
CNS

• Meningitis
• Bacteremea, O.M, skull osteo., neural canal
  defects.
• Neurosurgical procedures and VP shunt

31
Heart

• Bacterial endocarditis
• -Perforated heart valve
• -myocardial abscess
• -purulent pericarditis
• -Sudden death

32
Kidney

• Perinephric abscess
• UTI
• Staph. saprophyticus (CONS)
• Sexually active adolescent girls

33
G.I.

• Food poisoning
• Meat, mayonnase, creamed foods
• Short incubation period of 1 to 7 HRs
• Perfuse vomiting, no fever
• Test susp. food for staph bacteria/ toxins

34
Diagnosis

• Isolate staph. bacteria
• Gram stain
• Identify Toxins

35
Treatment

• Penicillinase resistant antibiotics
• Oxacillin (Cloxacillin, Flucloxacillin)
• methicillin
• Nafcillin
• 1st generation cephalosporine, cefazolin
• (Ultracef)

36
Treatment cont.

• Betalacamase hyperprodcer staph.
• Amoxicillin/Clavulenic acid(Augumentin)
• Ampicillin/Salbactam
• Imipenem
• Fluoroquinilones
• 1st generation cephalosporin
• Vancomycin

37
(No Transcript)
38
Coagulase negative Staph. (CONS)

• Common Skin Flora
• Ubiquitous organism
• Has affinity to plastic (surface hydophobicity
  production of slim)
• Neonates, I/V access and shunt devices infections
  (nosocomial infections)

39
Clinical Conditions

• Premature neonatal sepsis/NEC.
• Older children sepsis is rare (minimal signs of
  sepsis)
• Persistent pactreamia usual with indwelling
  devices (I/V cath, VP shunt, cardiac grafts and
  prosthesis etc.)

40
Clinical Cond. Cont.

• Single positive blood culture is a contaminant
• UTI in adolescent girls Staphylococcus
  Saprophyticus (CONS)

41
Treatment

• Remove the access devices/shunts.
• May externalize the VP shunt.
• Vancomycin or Rifampin.
• Amoxicillin or Quinolones for the Staph
  Saprophyticus UTI.

42
(No Transcript)
43
Nosocomial Infections
44
Definition

• Infections not present or incubating at the
  time of admission that develop during admission
  or less than one incubation period after discharge

45
Definition cont.

• Infections 48 HRs or more after admission is
  assumed to be nosocomial unless the infection is
  clearly community acquired

46
Clean Surgery
47
Clean Surgery

• Incision through prepared normal skin and the
  operative field dose not include infected tissue
  , abscess, or entry into normally unsterile areas
  such as the bowel, the upper respiratory tract,
  or the lower female genital tract.

48
Rate of Nosocomial Infections

• Number of nosocomial infections divided by
  the number of patients at risk multiplied by 100

49
Epidemiology

• 1/3 hospital infections are nosocomial (estimate
  in the USA)
• i.e. 2 million patients
• i.e. 4 million patient days of
  hospitalization
• i.e. 4.5 Billion USD
• i.e. 17 Billion SAR
  

50
Epidemiology cont.

• In USA (1978) nosocomial inf. rate
• -All services 3.37
• -Pediatric services 1.2

51
Epidemiology cont.

• Common sites of ped. nosocomial infections (as
  per the NNIS)
• Blood stream
• Surgical sites
• Lower respiratory tract
• Urinary tract

52
Epidemiology cont.

• In adults
• Urinary tract
• Surgical sites
• Lower respiratory tract
• Blood stream

53
Epidemiology cont.

• Common PEDIATRIC nosocomial bacteria
• Staphylococcus aureus
• Escherichia coli
• CONS
• Klebsiella

54
Epidemiology cont.

• Common NEONATAL nosocomial bacteria
• CONS
• Staphylococcus aureus
• Escherichia coli
• Group B sterptococci
• Klebsiella

55
Epidemiology cont.

• Areas of high nosocomial infection rates
• NICU
• PICU
• Burn Units

56
Risk Factors of Nosocomial Inf.

• General risk factors
• Prior colonization with nosocomially acquired
  bacteria
• Catheters
• Exposure to antibiotics
• Specific risk factors
• Inhalation equipments
• Specific monitoring caths e.g. arterial cath
  etc.
• Viral infections

57
General risk factors

• Prior colonization
• Klebsiella colonization after admission gave 50
  incidence of infection
• Inhalation therapy, N/G suction and antibiotics
  are behind the colonization

58
General risk factors

• Catheters
• Increase risk of septicemia with method of
  insertion, type of solution and duration of
  placement (I/V catheter)
• Major risk of septicemia in neonates
• Urine catheter is a risk for UTI in females,
  elderly and critical pt.s
• Risk increase with method of insertion, length of
  tube and break of the system

59
General risk factors

• Exposure to Antibiotics
• Prior use of broad spectrum antibiotics
• Normal flora protect the host through blocking
  the surface receptor/attachment sites

60
Specific risk facors

• Special catheters
• Pressure trasducers
• Arterial catheters
• Swan-Ganz catheters

61
Specific risk facors

• Viral infections
• RSV close contact with infants at risk
• Varicella ( 8-21 days incubation) and risk for
  nonimmune and immune suppressed. Screen hospital
  personnel
• Rota virus

62
Prevention and control of nosocomial infections

• General measures
• A team of infection control team
• Enforce surveillance of equipments, disinfection
  and isolation techniques

63
Specific risk factors

• Inhalation equipments
• Nebulizers and humidifiers
• Risk of necrotizing pneumonia
• Decontamination with .25 acetic acid and
  ethylene oxide

64
Prevention and control of nosocomial infections

• Universal precautions
• Barrier precautions prevent exposure
• Hand wash
• Proper handling of sharp instruments
• Resuscitation equipments
• Personnel with exudative lesions
• Pregnant health workers

65
Prevention and control of nosocomial infections

• Isolation techniques
• Apply specific isolation to specific diseases

66
Prevention and control of nosocomial infections

• Hand wash practice
• Most effective and least expensive practice to
  prevent transmission of pathogens
• Educate personnel of the method of hand wash (15
  seconds with warm water and soap then dry and
  turn faucet with towel)

67
(No Transcript)
68
(No Transcript)
69
Prevention and control of nosocomial infections

• Intravenous therapy
• Hand wash
• Clean site with 70 alcohol and 10
  providone-iodine
• Preferred locations in pediatrics are scalp,
  hands and foot
• Minimize duration if possible
• Prophylactic antibiotics are not recommended
• Remove catheter if sign of inflammation