Background Methicillin‐resistant Staphylococcus aureus remains a major cause of health care‐associated infection in high‐risk units such as burn and cancer wards. In settings where advanced genotyping schemes are not routinely available, combining complementary molecular typing methods can improve characterization of genetic diversity for surveillance purposes. Methods Over a nine‐month period, 54 nonduplicate MRSA isolates were collected from a burn hospital ( n = 30) and a cancer hospital ( n = 24) in Sulaymaniyah, Iraq. Species identity and methicillin resistance were confirmed by nuc and mecA PCR. Isolates were characterized using spa sequencing, sequence‐based coagulase ( coa ) VNTR typing and REP‐PCR fingerprinting. Discriminatory power was quantified using Simpson’s index of diversity (SID), and intermethod concordance was assessed using the adjusted Rand index and adjusted Wallace coefficients. Results spa typing identified 16 types, dominated by t037 and t304 (SID = 0.884). Sequence analysis of the coa VNTR region revealed 38 distinct nucleotide repeat units encoding 20 amino acid motifs, resolving 10 composite coa types (SID = 0.839). REP‐PCR generated 36 fingerprint patterns grouped into 15 clusters, yielding the highest numerical discrimination (SID = 0.921). Concordance was moderate between spa and coa typing but low between REP‐PCR and either sequence‐based method, indicating substantial short‐range genetic heterogeneity (distinct REP‐PCR fingerprints). Shared spa / coa types across both hospitals indicate the presence of common genetic backgrounds, while heterogeneous REP‐PCR fingerprints within this cohort highlight fine‐scale genetic heterogeneity. Conclusions MRSA isolates from these hospitals were dominated by a limited number of spa types and coa VNTR variants, with substantial fine‐scale genetic heterogeneity. spa typing provided a portable lineage‐background framework, sequence‐based coa VNTR analysis added reproducible, complementary resolution at a virulence‐associated locus, and REP‐PCR improved short‐range discrimination when interpreted alongside sequence markers, supporting pragmatic surveillance of MRSA genetic diversity. This work adds a sequence‐resolved coa VNTR repeat catalog and a quantitative cross‐method analysis to guide selection and interpretation of complementary MRSA typing schemes.
Shwan et al. (Thu,) studied this question.