GRAM POS BACTERIA Flashcards
- Gram-positive cocci in pairs and clusters
- Most common cause of pyogenic skin & soft tissue infection
- Transmission: primarily by direct contact, auto-
inoculation - most common cause of Osteomyelitis and suppurative arthritis in children
- common cause of acute endocarditis
- principal cause of TSS.
Staph aureus
- acute multisystem disease
- Caused by TSST-1 producing S. aureus
- Menstruating women ‘
- Nonmenstrual TSS
- TSST-1 causes massive fluid loss from the intravascular space
Toxic Shock Syndrome
most common species of CONS
S. epidermidis
Manifestation of CONS
- Bacteremnia
- endocarditis
- CSF shunta
- UTI
DOC OF CONS
Vancomycin
- Gram positive, lancet-shaped, polysaccharide
encapsulated diplococcus - Common inhabitants of the respiratory tract of humans
- Transmission: respiratory droplets
- Polysaccharide capsule important pathogenicity factor
- 2nd most common cause of meningitis
Streptococcus pneumonia Pneumococcus
DIAGNOSIS of Streptococcus pneumonia
lancet-shaped diplococci on Gram staining
Tx of Meningitis for Strep pneumonia
- If penicillin susceptible: Penicillin or Cefotaxime or
Ceftriaxone - If nonsusceptible: Vancomycin + high dose Cefotaxime or Ceftriaxone
Tx of Invasive infections outside CNS for Strep pneumonia
- High dose Cefotaxime or Ceftriaxone
- Penicillin allergy: Clindamycin, Erythromycin, TMP-SMX
- Vaccine can’t be given in patients <2 yrs old
- Can be given in infants
- PPSV 23
- PCV 13
Prophylaxis (for high risk children) for Streptococcus pneumonia
- Penicillin V potassium
- Benzathine Penicillin G IM every month
- Gram-positive cocci in chains
- Natural reservoir: human
- Virulence due to:
> M protein
> Erythrogenic toxins - Manifestations
> RTI
+ Acute pharyngitis
+ Pneumonia
> Impetigo
> Erysipelas
> Scarlet fever
GAS
Group A Streptococcus: Severe invasive disease
- GAS Toxic Shock Syndrome
- GAS necrotizing fasciitis
- Focal and systemic infections not meeting criteria for 1&2
DOC for GAS
penicillin for 10 days
JONES CRITERIA: MAJOR MANIFESTATION
- Carditis
- Polyarthritis
- Erythema marginatum
- Subcutaneous nodules
- Chorea
JONES CRITERIA: MINOR MANIFESTATION
- Arthralgia
- fever
- Elevated acute phase reactants:
> Erythrocyte sedimentation rate
> C-reactive protein
> Prolonged PR interval
Dx of ARF can be made without fulfilling the Jones criteria:
- Chorea
- Indolent carditis
- Recurrence of ARF
Duration of Secondary: prevention of pharyngitis in Pxs at risk of recurrent ARF
- Rheumatic fever without carditis: 5 yr or until 21 yr of age, whichever is longer
- Rheumatic fever with carditis but without residual heart disease (no valvular disease”): 10 yr or until 21 yr of age, whichever is longer
- Rheumatic fever with carditis and residual heart disease (persistent valvular disease”): 10 yr or until 40 yr of age, whichever is longer, sometimes lifelong prophylaxis
- Anaerobic gram positive cocci in chains or pairs
GBS
CXR LAB FINDINGS
reticulogranular patterns, patchy infiltrates, opacification, increased interstitial markings
GBS
- DOC
- Initial empiric treatment
- Penicillin G
- Ampicillin + Aminoglycoside
- acute toxin-mediated disease; occurs worldwide
especially in tropical countries - Aerobic, non-encapsulated,non-spore-forming, gram-positive bacillus
- Exclusive inhabitant of human mucous membranes and skin
- Toxigenicity occurs only when the bacillus is lysogenized by a bacteriophage carrying the genetic info for the tox gene
- Only the toxigenic strains can cause severe disease
- 4 biotypes: mitis, intermedius, belfanti, gravis
Corynebacterium diphtheriae
Transmission: Corynebacterium diphtheriae
- Airborne respiratory droplets
- Direct contact with respiratory secretions
- Exudate from infected skin lesions
- Mainstay of therapy
- Neutralizes circulating (unbound) toxin (efficacy diminishes with elapsed time after onset of mucocutaneous Sx)
- Dose: 20,000-120,000 U based on toxicity, size & site of membrane and duration of illness
- Available only from CDC
Equine Diphtheria antitoxin
Staining Dx of Corynebacterium diphtheriae
club-shapes forms
Classified based on site of disease: Corynebacterium diphtheriae
- Scaly rash/nonhealing ulcers with clearly demarcated edges & gray-brown membrane
- Extremities more often affected
- More prolonged bacterial shedding
- Greater contamination of environment
- Increased transmission to the pharynx and skin of close contacts
Cutaneous Diphtheria
Classified based on site of disease: Corynebacterium diphtheriae
- fever
- Hoarseness
- Barking cough
- Complications: airway obstruction, coma, death
Laryngeal Diptheria
Classified based on site of disease: Corynebacterium diphtheriae
- Most common site (94%)
- Manifestations:
> Sore throat*
> Fever, dysphagia, hoarseness - Substantial systemic absorption of toxin
- Early sx -> bluish-white memb —> grayish-green or black
Pseudomembrane adheres to tissue —> bleeding on forceful removal - Underlying soft tissue edema +enlarged lymph nodes —> Bull-neck appearance
- Danger of airway compromise
Pharyngeal & Tonsillar Diphtheria
Classified based on site of disease: Corynebacterium diphtheriae
- Serosanguineous, mucopurulent discharge
- White membrane on nasal septum
- Shallow ulceration of external nares, upper lip
- Fairly mild — poor systemic absorption of toxin in this location
Anterior nasal Diphtheria
- Halts toxin production
- Treats localized infection
- Prevents transmission to contacts
Antibiotics: Erythromycin
helps protect your child against: diphtheria. tetanus. pertussis (whooping cough)
The 6-in-1 vaccine for free, also commonly known as the DTaP/IPV/Hib/HepB vaccine
