Septicaemia

Bacteraemia = "presence of bacteria in blood"

Aet
- N flora - access to bloodstream
eg dental & soft tissue abscesses/cholecystitis/appendicitis/diverticulitis/upper renal tract infection
- **prosthetic surgery (orthop, CVS, neuro) - prosth can be 'seeded' by organism & infect irrev
- Pneumonia - S pneum
- Skin - S pyogenes/S aureus

Sy&Si

Asy (pray that it's not)
or
Severely ill
Fever (absent with child/eld)
Shock (later presentation)
Depressed consciousness (confused/drowsy)
?GN-ve vs G+ve - cannot clinically differentiate

h/e signs poss...
- N meningitidis - purpura
- S Aureus - embolic lesions
- N Gonorrhoeae - arthritis

Dx
x2 peripheral blood cultures b4 Tx
Septic screen
- blood cultures

- urine cult

- sputum cult

- CSF

- skin swabs

- CXR/AXR
- abdo US

Tx
1) empirical DO NOT WAIT!!! - BSp

Empirical Therapies

Skin - strep & staph
-Flucloxacillin
Abdo sepsis - enterobacteriaceae & obligate anerobes
-Ceftazidime & metronidazole/meropenem
Prosthetic devices - staphylococci
-Fluclox/vanc
Urinary Tract - enterobacteriaceae & enterococci
-Piperacillin/tazobactam (init if Hosp acq & sev)
Meninges - N Meningitidis, S pneumoniae, H influenzae
-Benzyl penicillin/Cefotaxime

Line-related septicaemia
- increased risk with time
- S aureus, S epidermidis, Klebsiella
- look for inflammation - remove if susp infection

- Ix - blood cultures from peripherally through cannula
- Tx - ABs, Glycopeptide (MRSA)

- Prevention - ANTT, device w/o dead space/side ports, good dressing, staff hygiene, regular inspection, periph resited every 48hrs, central & tunnelled lines - inspection changed with evidence of infection

- Cx - septicaemia, endocarditis, metastatic infection (eg OMyelitis)

Puerperal Fever
Sev
*bacteraemic infection
Entry of pathogens throo placental bed/cervix following delivery
*w/i 7d of deliv

Sy
Fever
Back pain
Offensive lochia
Shock

Ix

Fever - if in early puerperium = Ix! - bl/ur cult/endocervical swabs

Tx
Empirical
3rd gen cephalosporin & metronidazole
Remove any retained products of contraception
Intensive care if necess

Cx
DIC

Infectious Diseases - Empirical Therapies

Skin

Cellulitis

Strep. pyogenes
± Staph. aureus

Mild/Moderate (oral)
Penicillin V + flucloxacillin
or Co-amoxyclav alone
or Erythromycin alone (if penicillin allergic)

Severe (IV)
Benzylpenicillin + flucloxacillin
or Co-amoxyclav alone

Bones & Joints

Osteomyelitis & Septic Arthritis
Staph. Aureus

Streptococci

Staph Epidermidis

ALL CASES ARE SEVERE
IV Flucloxacillin (+ fusidic acid for osteomyelitis)
or Clindamycin alone

ENT Infections

Sinusitis & Otitis Media

Viruses
Strep. pneumoniae

Haemophilus influenzae

Nothing
or Amoxycillin
or Erythromycin

Throat Infections

Viruses

Strep. pyogenes

Nothing

or Penicillin V

or Erythromycin

Respiratory Infections

Community Acquired Pneumonia
Pneumococcus (Strep. pneumoniae)
‘Atypicals’

- Mycoplasma pneumoniae

- Chlamydia pneumoniae

- Legionella

Mild/Moderate (oral)
Amoxycillin 

+ Erythromycin (if ‘atypical suspected’)

or Erythromycin alone

Severe (IV)
Co-amoxiclav

or 2nd/3rdgen. cephalosporin + Macrolide

Pulmonary tuberculosis

Mycobacterium tuberculosis

Rifampicin + Isoniazid + Pyrazinamide + Ethambutol (2 months)
Rifampicin + Isoniazid (4 months)

Acute Exacerbations of COPD
Pneumococcus (Strep. pneumoniae)

Haemophilus influenzae

Moraxella catarrhalis

Amoxycillin + Clarithromycin

or Tetracycline (if penicillin allergic)

Urinary Tract

Urinary Tract Infection
E. Coli (60-90%)
Proteus (10%)
Klebsiella

Mild/Moderate (oral)
Trimethoprim (unless pregnant)
or Amoxycillin

or Nitrofurantoin

or Ciprofloxacin
(A 3-day course is usually sufficient)

Severe (IV)

Co-amoxiclav

or 2nd/3rd gen. cephalosporin ± gentamicin

GI Tract Infections

Gastro-enteritis
Often viral and self-limiting
No antibiotic usually indicated

Campylobacter
Ciprofloxacin

Salmonella
Ciprofloxacin

Typhoid fever
Ciprofloxacin

Pseudomembranous colitis
Oral metronidazole

or Oral Vancomycin

GI Tract Surgery & Peritonitis - Antibiotic Prophylaxis and Treatment

Staph. aureus (wounds)
Mixed faecal flora including anaerobe

2nd/3rd gen. cephalosporin + metronidazole

or Co-amoxyclav alone

Meningitis

Meningococcus (N. meningitidis)

Pneumococcus (Strep. pneumoniae)

Haemophilus influenzae

ALL CASES ARE SEVERE

Ceftriaxone IV

Prophylaxis for Meningococcal contacts

Rifampicin

or Ciprofloxacin

Septicaemia

Many possible causes

‘Blind therapy’ is broad spectrum + additional cover for strong clinical suspicion
Definitive therapy based on culture results

Community Acquired

Ceftriaxone ± gentamicin
Add Metronidazole if anaerobes suspected
Add Flucloxacillin is Staph. aureus suspected
Add Vancomycin if MRSA suspected

Infectious Diseases - Antibiotics Profiles

General Principles

Empirical Therapy

Likely organisms

Severity of infection

Investigations
Microbiological:
Swabs
Fluids e.g. sputum, urine, aspirates
Blood culture
Serology

Bloods

FBC

Inflammatory markers

Radiology

Review Progress

Clinical

Cultures & Sensitivity

Adverse Effects

Penicillins
Inhibit bacterial cell wall synthesis
Well tolerated:

Rash (common)

Anaphylaxis (rare)
Excreted in urine
‘Safe’ in pregnancy
Destroyed by beta-lactamase (S. aureus and some anaerobes)

Except:

Flucloxacillin - beta-lactamase resistant

Amoxycillin & clavulinic acid - beta-lactamase inhibitor, may cause jaundice

Benzylpenicillin (IV) or Penicillin V (oral)
Gram +ve (strep)
Meningococcos
Gram +ve Clostridia species of Anaerobes

Ampicillin/Amoxycillin
Gram +ve (strep)
Gram -ve

Flucloxacillin

1st choice - S. aureus

Co-amoxyclav (amox & clavulinic acid)
Gram +ve (strep)
S. aureus
Gram -ve
Anaerobes

Cephalosporins

Inhibit bacterial cell wall synthesis
Broad spectrum
Well tolerated, though 10% cross-over with penicillin allergy
Excreted in urine
‘Safe’ in pregnancy
Resistant to beta-lactamase (S. aureus and some anaerobes)
x cover Enterococci

Cefuroxime (‘2nd generation’)
Gram +ve
S. aureus (not 1st choice)
Gram -ve

Ceftriaxone (‘3rd generation’)
Gram +ve
S. aureus (not 1st choice)
Meningococcus
Gram -ve

Ceftazidime (‘anti-pseudomonal’)
Gram +ve
S. aureus
Gram -ve
Some Pseudomonas

Aminoglycosides

e.g. Gentamicin

Inhibit bacterial protein synthesis
Reserved for severe Gram –ve infections
IV only
Excreted in urine
Important adverse effects:

Nephrotoxic

Ototoxic
Monitor blood levels
Only use in pregnancy if benefit outweighs risk

Aminoglycosides
Gram -ve

Pseudomonas
Mycobacteria - some, not 1st line

Macrolides

e.g. erythromycin, clarithromycin

Inhibit bacterial protein synthesis
Atypical pneumonias
Patients allergic to penicillins
Well tolerated

GI upset (common)

Jaundice (rare)
Erythromycin inhibits cytochrome P450

Macrolides
Gram +ve

S. aureus

Atypicals

Tetracyclines

Inhibit bacterial protein synthesis
Broad spectrum including most atypicals
Over-used in the ‘60s and ‘70s - widespread resistance
Deposits in bone and teeth - grey staining
Avoid in pregnancy and children < 12 years
May exacerbate renal impairment

Tetracyclines

Gram +ve (Used as empirical alternatives to penicillin in mild/moderate URTI, also used for acne)
Gram -ve
Atypicals (Treatment of choice for microbiologically proven Chlamydia, Rickettsia, Brucella, Borrelia)

Trimethoprim

Bacterial dihydrofolate reductase inhibitor
Broad spectrum, some resistance
Well tolerated
Excreted in urine
Avoid in pregnancy
Useful for empirical treatment of UTI and respiratory infections

Trimethoprim

Gram +ve
Gram -ve

Quinolones

e.g. ciprofloxacin

Inhibits DNA gyrase

Mainly Gram –ve aerobes inc some pseudomonas
Over-used in the ‘80s - widespread resistance
Rarely = seizures or tendon inflammation/rupture
Excreted in urine
Avoid in pregnancy

Quinolones

Meningococcus - Prophylaxis only
Gram -ve
Some Pseudomonas

Glycopeptides

e.g. vancomycin, teicoplanin

Inhibit cell wall synthesis

Severe Gram +ve infections resistant to penicillins
Inc. MRSA (resistant to flucloxacillin)
Vancomycin:

Nephrotoxicity

Ototoxicity

‘Red man’ syndrome
Requires blood levels

Glycopeptides

Gram +ve
S. aureus
Anaerobes - Clostridia species

Metronidazole

Inhibits bacterial DNA synthesis
Anaerobic bacteria and protozoal infections only
Very low resistance
Well tolerated but can cause metallic taste
Avoid if possible in pregnancy

Metronidazole

Anaerobes

Infective Endocarditis

Infective Endocarditis has several predisposing factors.

These include
 - Rheumatic heart disease
 - Mitral Valve Prolapse
 - Intravenous Drug User
 - Congenital Heart Disease (*bicuspid aortic valve)
 - Prosthetic Valve
 - HOCM

(imagine an pregnant (Cong. HD) IVDU, collapsed (MV Prolapse) in a room (Rheum), with a prosthetic leg (prosthetic valve) made by the HCME (HOCM) company) Yeah, I know it's messed up.

Several organisms tend to be the culprit with this condition:

• Viridans Streptococci
• Streptococcus Bovis
• Staphylococcus Aureus
• Enterococci
• Gram Negative

(imagine a smiling (VS) cow (SB) in a pink cloak (gram -ve) holding a staff (SA) beckoning you to enter (Enterococci).

Clinical Features include:

 A) Fever (*90%)

 B) Anorexia & Weight Loss

 C) Clubbing

 D) Splinter Haemorrhages

 E) Osler's Nodes

 F) Janeway's Lesions

 G) Petechiae

 H) Roth's Spots

 I) New or changing murmur

 J) Systemic Emboli

 K) Splenomegaly

 L) Haematuria