STANDARD OPERATING PROCEDURES FOR THROAT SWAB CULTURE

1. SPECIMEN:

1. Throat swab (2 in numbers) should be collected under direct visualisation without touching the tongue or buccal mucosa.

2. CULTURE MEDIA:

1. Blood Agar (BA)
2. Loeffler's serum slope, optional
3. Potassium Tellurite (KT) , optional

3. PROCEDURE:

1. Inoculate the sample in BA.

(Note- If Diptheria is suspected, inoculate in Loeffler's serum slope , 1/2 BA and 1/2 Potassium tellurite medium. Subculture from Loeffler's slope into the rest of 1/2 of KT and BA. Preferably within 4-6 hours of inoculation)

2. After 24 hours,
   1. Process b-haemolytic streptococci, if grown. If isolation and grouping needs further 24

hours then a preliminary report should be despatched.

2. In patients where chances of aspiration pneumonia are high, process pure cultures of Streptococcus viridans ,Gram neg. bacteria, or Streptococcus pneumoniae . In immuno-compromised patients, also report of any alteration in normal flora.
3. If only normal flora:- Report as “Non b-haemolytic streptococci grown, Normal, No other common respiratory, pathogen grown”.
4. If no growth is seen -Inappropriate sample, dry swab. Ask for repeat sample