Molecular identification of microorganisms in chronic wounds, Republic of Guinea (Conakry)

Abstract

Skin infections are common in sub-Saharan Africa, including chronic wounds. This study aimed to assess the
presence of several microorganisms in skin specimens from patients with chronic wounds and healthy
people in Maferinyah (Republic of Guinea). Eighty-four skin samples from the wounds of 20 patients (42 edge
swabs and 42 center swabs) and twenty-two skin samples from 11 healthy people were analyzed by real-time
quantitative PCR and standard PCR assays combined with sequencing. Pseudomonas aeruginosa was the
most frequently detected bacterium, which was significantly more prevalent in patients (80%, 16/20) than in
healthy people (9%, 1/11; p<0.001), followed by Staphylococcus aureus which was only detected in patients
(60%, 12/20; p<0.001). Streptococcus pyogenes was also more frequently detected in patients (30%, 6/20) than
in healthy people (9%, 1/11) but the difference was not statistical significant. Rickettsia felis was also detected
for the first time in Guinea, in one patient. Finally, species of the genus Acinetobacter were also frequently
and exclusively detected in patients (80%, 16/20). Acinetobacter baumannii (2/20, 10%), Acinetobacter
nosocomialis (10%), Acinetobacter junii (1/20, 5%), Acinetobacter lwofii (5%), and Acinetobacter
guangdongensis (5%), which was detected for the first time in skin, were identified. Acinetobacter junii and
Acinetobacter lwofii were observed in different samples from the same patient. For the 11 other patients,
polymicrobial infections featuring several species of the genus Acinetobacter were observed. Overall, many
different bacteria which may encourage wound enlargement or delayed healing were observed in chronic
wounds.