1. Bacterial superinfection of chicken pox: Best antibiotic to use?
Joshua Burns & Megan Collins

2. Paediatric varicella hospitalisations in France: a nationwide survey1
1575 patients hospitilised between March 2003 and July 2005
From 200 paediatric wards across France
Median age was 2 years, 87.5% were <5 years, and 2.7% were neonates
Based on national surveillance network data
Results
Skin/soft tissue infection was most common complication (36.5%)
Other common complications: Neurologic (8.1%), febrile seizures (6.4%), bacterial pneumonia (3.1%), ENT (2.9%), varicella pneumonia (2.4)
In order to better estimate the burden of paediatric hospitalisations caused by varicella in France, a national surveillance network was established. The present report presents a descriptive analysis of the results of surveillance for the first 2 years.
Each patient admitted for ongoing varicella and/or complications or events attributed to varicella was recorded. Hospitalisations unrelated to varicella, and conditions with an onset of varicella >5 days after admission, were excluded.
Skin/soft tissue included cellulitis, abscess, necrotizing skin lesion, scalded skin syndrome and necrotizing fasciitis
Most common neuro complications were cerebellitis and encephalitis

3. Results (continued)
A pathogen was identified in 268 cases of skin/soft tissue superinfection
158 were Staphylococcus Aureus (59%)
88 were Group A Beta-haemolytic streptococci (33%)
14 were Staph. Aureus + Group A strep (5%)
97% cases were Staph. Aureus or Group A Strep.
Strengths
Weaknesses
Correct demographics (age-range, hospitilised)
Retrospective study
Sufficient sample size
Methods for how organism was determined are unclear in paper
Recorded all complications
Remaining 3% including Staphylococcus epidermidis, Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis

4. Disease manifestations and pathogenic mechanisms of Group A Streptococcus2
Narrative review
American Society for Microbiology – Clinical Microbiology Reviews
‘Group A Strep remains exquisitely and universally sensitive to penicillin’
Suggests use of beta-lactam antibiotics for group A strep
Clindamycin, macrolides and cephalosporins all also appropriate
Slection bias?

5. Skin infections that have progressed to bacteraemia
Antimicrobial Activities of Ceftaroline and Comparator Agents against Bacterial Organisms Causing Bacteremia in Patients with Skin and Skin Structure Infections in U.S. Medical Centers, 2008 to 20143
Bacteria collected as part of Assessing Worldwide Antimicrobial Resistance Evaluation (AWARE)
Skin infections that have progressed to bacteraemia
In adult population
Included 670 Staph. Aureus and 138 Beta-haemolytic Streptococci
Not accounting for local resistance profiles

6. Staphylococcus Aureus (670) Beta-haemolytic streptococci (138)
Antibiotic
% Susceptibility
Ceftaroline
97.9
Ceftriaxone
49.4
Oxacillin
Clindamycin
82.4
Daptomycin
99.7
Erythromycin
39.0
Levofloxacin
59.0
Linezolid
99.9
Tetracycline
95.8
Tigecycline
100
Vancomycin
Beta-haemolytic streptococci (138)
Antibiotic
% Susceptibility
Ceftaroline
100
Ceftriaxone
Penicillin
Clindamycin
84.8
Daptomycin
Erythromycin
71.0
Levofloxacin
99.3
Linezolid
Tetracycline
44.9
Tigecycline
Vancomycin
Oxacillin, most similar to flucloxacillin – resistant to penicillinase commonly produced by staph aureus

7. Staphylococcus Aureus (584)
Skin and soft tissue infections in Latin American medical centers: four-year assessment of the pathogen frequency and antimicrobial susceptibility patterns4
Antimicrobial susceptibility of isolates collected from skin and soft tissue infections during the first 4 years ( ) of the SENTRY Antimicrobial Surveillance Program
Staphylococcus Aureus in 32.8%
Staphylococcus Aureus (584)
Antibiotic
% Susceptibility
Penicillin
5.3
Co-amoxiclav
71.6
Tetracycline
71.2
Linezolid, daptomycin and vancomycin again showed 100% efficacy against staph aureus. Not first line though

8. Chickenpox in adults - Clinical management5
“Secondary bacterial infection with Staphylococcus aureus or Group A Streptococci is a common complication of chickenpox … treatment with appropriate antibiotics, such as flucloxacillin, co-amoxiclav or a macrolide should be considered.’’
anecdotal

9. Conclusions
Superinfected chicken pox lesions most likely to be Group A Streptococcus or Staphylococcus Aureus
Literature consensus is that Group A strep. is susceptible to penicillin antibiotics, including co-amoxiclav
Co-amoxiclav seems to be good choice for most but not all of Staph. Aureus strains
Could argue that clindamycin could be added in for their additional cover and as they are protein synthesis inhibitors, they reduce the effect of the toxins produced by the organisms, lowering risk of toxic shock or scalded skin

10. References
1 Grimprel E, Levy C, de La Rocque F, Cohen R, Soubeyrand B, Caulin E, Derrough T, Lecuyer A, d'Athis P, Gaudelus J. Paediatric varicella hospitalisations in France: a nationwide survey. Clinical microbiology and infection May 1;13(5): Walker MJ, Barnett TC, McArthur JD, Cole JN, Gillen CM, Henningham A, Sriprakash KS, Sanderson-Smith ML, Nizet V. Disease manifestations and pathogenic mechanisms of group A Streptococcus. Clinical microbiology reviews Apr 1;27(2): Sader HS, Flamm RK, Mendes RE, Farrell DJ, Jones RN. Antimicrobial activity of ceftaroline and comparator agents tested against bacterial organisms causing bacteremia in patients with skin and skin structure infections in United States medical centers ( ). Antimicrobial agents and chemotherapy Feb 8:AAC Sader HS, Jones RN, Silva JB, SENTRY Participants Group. Skin and soft tissue infections in Latin American medical centers: four-year assessment of the pathogen frequency and antimicrobial susceptibility patterns. Diagnostic microbiology and infectious disease Nov 30;44(3): Tunbridge AJ, Breuer J, Jeffery KJ. Chickenpox in adults–Clinical management. Journal of Infection Aug 31;57(2):