化脓菌分离鉴定过程（二）肠道菌分离鉴定过程（二）

Experiment Two

化脓菌分离鉴定过程Objective掌握从临床标本中分离和鉴定化脓性球菌的原则和方法。辅助临床诊断及指导临床用药。

Identified method for pyogenic cocci

Gram-stainIsolation and culturePure culture Direct identification The antibiotic susceptibility test

Gram-stain

Morphological characteristics 葡萄球菌－球形，呈葡萄串状排列链球菌－链状排列肺炎链球菌－矛头状，成双排列，尖端向外

Staphylococci are Gram-positive cocci, typically arranged in clumps or Grape-like clusters

Isolation and culture

Cultural• Specimens planted on blood agar plates

give rise to typical colonies in 18h at 37℃

Isolation and culture colonial characteristics

• 致病性葡萄球菌• 中等大小（ 1 ～ 2mm）、表面光滑、边缘整齐、不透明、有溶血环、产生金黄色色素或白色色素

• 乙型溶血性链球菌• 菌落较小（ 0.5 ～ 0.75mm）、灰白色、表面光滑、有光泽、有清晰透明溶血环

• 甲型溶血性链球菌 /肺炎链球菌• 细小菌落周围产生草绿色溶血环。

纯培养（ Pure culture）Materials

• Agar slope culture• Colonies on agar plate

Specimens Different specimens should be taken depending

on the kind and the process of the disease.

革兰染色

Isolation and culture

Culture medium: S.S agar Method: streak plate

Results: unpathogenetic: middle size, red, opaque Suspect colonies: small, colorless, semiopaque

Primary identification

双糖铁培养

细菌基本形态观察葡萄球菌链球菌淋病奈瑟菌大肠杆菌霍乱弧菌