For routine cultures, a loopful of the sputum is

inoculated onto one/two blood agar plates. When two are

inoculated one is incubated in a 5–10% CO2 atmosphere. A

smear is made from specimen and stained by Gram’s stain.

If the need be Ziehl-Neelsen staining can also be done.

Throat and Nasal Smears

Organisms commonly isolated from a normal throat

are Alpha-hemolytic streptococci, Neisseria catarrhalis,

staphylococci, non-hemolytic streptococci, pneumococci

and Coliform bacilli. The pathogens usually encountered are

beta-hemolytic streptococci, Corynebacterium diphtheriae,

Bordetella pertussis, meningococci, Staphylococcus aureus,

Haemophilus influenzae and Candida albicans.

The sterile swabs should be first moistened with normal

saline (sterile) and then rubbed over the infected area.

A blood agar plate is inoculated. A Gram’s stain is rarely

necessary except in cases where diphtheria or Vincent’s

angina are suspected. If diphtheria is suspected, the

smears should by stained by Albert’s, Ponder’s or Neisser’s

techniques.