Association of pvl gene with incomplete hemolytic phenotype in clinical Staphylococcus aureus

Figures & data

Table 1 Constituent ratios of departments where strains were isolated

Department	Strains, n (%)
Neurology	9 (4.27)
Orthopedic	21 (9.95)
Pediatrics	5 (2.37)
ENT	3 (1.42)
Out-patient	11 (5.21)
Infectious diseases	11 (5.21)
Oncology	2 (0.95)
Intensive Care Unit	24 (11.37)
General surgery	15 (7.11)
Respiration	3 (1.42)
Plastic surgery	6 (2.84)
Cerebral surgery	3 (1.42)
Urology	5 (2.37)
Endocrinology	14 (6.64)
Dermatology	24 (11.37)
Burns	12 (5.69)
Nephrology	18 (8.53)
Hematology	6 (2.84)
Obstetrics and gynecology	1 (0.47)
Plastic surgery	9 (4.27)
Rheumatism and Immunological Disease	9 (4.27)
Total	211(100.00)

Figure 1 Hemolytic phenotype comparative analyses of Staphylococcus aureus on blood agar plates.

Notes: (A) S. aureus strains with incomplete hemolytic phenotype (SIHP) strains growing in the microaerophilic condition. (B) S. aureus strains with complete hemolytic phenotype (SCHP) control strain of S. aureus ATCC25923. (C) Several SIHP colonies aggregated, forming a grid-like hemolytic phenotype. (D) SIHP strains after ten serial passages.

Figure 2 Detection of the pvl gene.

Notes: ATCC49775. Due to limitations of instrument, only 14 pvl-positive strains are shown here.

Abbreviations: M, marker; P, pvl-positive strain; N, pvl-negative strain.

Figure 3 Comparison of pvl gene between Staphylococcus aureus strains with incomplete hemolytic phenotype (SIHP) strains and S. aureus strains with complete hemolytic phenotype (SCHP) strains.

Notes: **P<0.01.

Abbreviations: pvl, pvl-positive S. aureus; Npvl, pvl-negative S. aureus.

Figure 4 Antimicrobial characteristics of 211 Staphylococcus aureus in terms of 19 antibiotics.

Abbreviations: AMC, amoxicillin; AMP, ampicillin; CIP, ciprofloxacin; CLI, clindamycin; CRO, ceftriaxone; DAP, daptomycin; ERY, erythromycin; FOX, cefoxitin; GEN, gentamicin; I, intermediate; LNZ, linezolid; LVX, levofloxacin; MXF, moxifloxacin; NIT, nitrofurantoin; OXA, oxacillin; PEN, penicillin; QDA; quinupristin-dalfopristin; R, resistant; RIF, rifampin; S, susceptible; SXT, sulfamethoxazole–trimethoprim; TCY, tetracycline.

Figure 5 Comparison of MIC to vancomycin between Staphylococcus aureus strains with incomplete hemolytic phenotype (SIHP) strains and S. aureus strains with complete hemolytic phenotype (SCHP) strains as well as pvl-positive and -negative strains.

Notes: (NS), P>0.05, difference was not statistically significant.

Abbreviations: MIC, minimum inhibitory concentration; VAN, vancomycin; R, resistant; I, intermediate; S, susceptible; pvl, pvl-positive S. aureus; Npvl, pvl-negative S. aureus; NS, not significant.

Figure 6 Comparison of drug resistance to four antibiotics in pvl-positive and -negative strains.Notes: *P<0.05. pvl, pvl-positive Staphylococcus aureus; Npvl, pvl-negative S. aureus.

Abbreviations: CIP, ciprofloxacin; I, intermediate; LVX, levofloxacin; MXF, moxifloxacin; R, resistant; RIF, rifampin; S, susceptible; pvl, pvl-positive Staphylococcus aureus; Npvl, pvl-negative S. aureus.

Figure 7 Comparison of drug resistance to seven antibiotics between Staphylococcus aureus strains with incomplete hemolytic phenotype(SIHP) strains and S. aureus strains with complete hemolytic phenotype (SCHP) strains. Notes: **P<0.005; *P<0.05.

Abbreviations: CIP, ciprofloxacin; CRO, ceftriaxone; FOX, cefoxitin; GEN, gentamicin; I, intermediate; LVX, levofloxacin; MFX, moxifloxacin; OXA, oxacillin; R, resistant; S, susceptible.

Data availability

All data generated or analyzed during this study are included in this published article.