Specific PCR, bacterial culture, serology and  pharyngeal sampling to enhance the aetiological  diagnosis of cellulitis.
It is often difficult to obtain a bacteriological diagnosis in patients with cellulitis. We examined the utility of molecular techniques and skin and throat cultures, as well as serology, in providing evidence of either Staphylococcus aureus or group A Streptococcus (GAS) presence inpatients with cellulitis. Samples were collected from patients with a clinical diagnosis of cellulitis who were recruited into a prospective placebo-controlled clinical trial (C4C study, EudraCT 2013-001218-14). Specific PCR, paired serology and culture for both organisms were carried out on a variety of samples where appropriate. Despite utilizing a range of diagnostic methods,a bacteriological diagnosis was only achieved in 43 % of patients with a clinical diagnosis of cellulitis. Seventeen per cent of patients tested positive for GAS by any method but only 4 % were positive by PCR, whilst S. aureus was detected in 34% of samples. Bacterial diagnosis in cases of cellulitis remains challenging. This is probably due to a very low bacterial burden with toxin production resulting in inflammation mediating skin damage. Further consideration for the need for long courses of antimicrobial therapy for cellulitis therefore appears merited.
Public Health England, Microbiology, Level 8, Queens Building, Bristol Royal Infirmary, Marlborough Street, Bristol BS2 8HW, UK.
Michelle S
MS
Toleman
Specialist Virology Centre, Public Health Laboratory Bristol, Public Health England, Myrtle Road, Bristol BS2 8EL, UK.
I Barry
IB
Vipond
Public Health England, Microbiology, Level 8, Queens Building, Bristol Royal Infirmary, Marlborough Street, Bristol BS2 8HW, UK.|University of Bristol, School of Social and Community Medicine, Canynge Hall, Bristol BS8 2PS, UK.
Richard
R
Brindle
D015373:Bacterial Typing Techniques; D002481:Cellulitis / Q000175:diagnosis* / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics; D006801:Humans; D010614:Pharynx / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D013203:Staphylococcal Infections / Q000175:diagnosis; D013211:Staphylococcus aureus / Q000145:classification / Q000302:isolation & purification; D013297:Streptococcus pyogenes / Q000145:classification / Q000302:isolation & purification
D004269:DNA, Bacterial