The document discusses testing conditions, media composition, and antimicrobial susceptibility testing recommendations for Haemophilus influenzae, Haemophilus parainfluenzae, and Neisseria gonorrhoeae. It recommends grouping antibiotics into groups A, B, and C for routine testing of Haemophilus species and lists suggested drugs for treating respiratory tract infections. It also provides testing details and antibiotic groupings for Neisseria gonorrhoeae susceptibility testing.

1. Haemophilus influenzae and
Haemophilus parainfluenzae

2. TESTING CONDITIONS
• Medium: Disk diffusion: Haemophilus Test
Medium (HTM)
Broth dilution: HTM broth

3. Haemophilus Test Medium
hematin stock solution is prepared by dissolving
50 mg of hematin powder in 100 mL of 0.01
mol/L NaOH with heat and stirring until the
powder is thoroughly dissolved.
30 mL of the hematin stock solution and 5 g of
yeast extract is added to 1 L of Mueller-Hinton
agar (MHA) and autoclaved.
After autoclaving and cooling, add 3 mL of a
nicotinamide adenine dinucleotide (NAD) stock
solution (50 mg of NAD dissolved in 10 mL of
distilled water, filter sterilized) aseptically

4. Testing conditions
• Inoculum: Direct colony suspension,
equivalent to a 0.5 McFarland
standard
• Incubation: 35 ± 2 °C;
• Disk diffusion: 5% CO2; 16 to 18 hours
• Broth dilution: ambient air; 20 to 24 hours

5. Suggested grouping of antimicrobial agents that should be
considered for routine testing and reporting for Haemophilus
spp.
• GROUP A DRUGS • GROUP B DRUGS
PRIMARILY TESTED AND PRIMARILY TESTED AND
REPORTED REPORTED SELECTIVELY
 Ampiciilin  Ampicillin-Sulbactam
 Trimethoprim-  Cefuroxime(parenteral)
Sulfamethoxazole  Cefotaxime or
ceftazidime or
Ceftriaxone
 Chloramphenicol
 Meropenem

6. Suggested grouping of antimicrobial agents that should be
considered for routine testing and reporting for Haemophilus spp.
• GROUP C (SUPPLEMENTAL) - REPORT SELECTIVELY
 Azithromycin
 Clarithromycin
 Aztreonam
 Amoxycillin-Clavulanic acid
 Cefaclor
 Cefprozil
 Cefdinir or Cefixime orCefpodoxime
 Cefuroxime(oral)
 Ciprofloxacin or Levofloxacin or Lomefloxacin or Moxifloxacin or Ofloxacin
 Gemifloxacin
 Ertapenem or Imipenem
 Rifampin
 Telithromycin
 Tetracycline

7. MINIMAL QC Recommendations
Haemophilus influenzae ATCC® 49247
Haemophilus influenzae ATCC® 49766
Escherichia coli ATCC® 35218 (when testing
amoxicillin-clavulanic acid)

8. Empiric therapy for respiratory tract infections
 Amoxicillin-clavulanic acid,
 Azithromycin,
 Clarithromycin,
 Cefpodoxime,
 Cefixime,
 Cefuroxime,
 Cefaclor,
 Cefprozil,
 Loracarbef,
 Cefdinir,
 Telithromycin

9. H. influenzae from CSF following
drugs should be reported routinely.
Ampicillin
Third Generation Cephalosporins
Chloramphenicol
Meropenem

10. • The results of ampicillin susceptibility tests
should be used to predict the activity of
Amoxicillin.
• The majority of isolates of H.influenzae that
are resistant to Ampicillin and Amoxicillin
produce a TEM-type β-lactamase.
• In most cases, a direct β-lactamase test can
provide a rapid means of detecting resistance
to ampicillin and amoxicillin.

11. • Rare BLNAR strains of H. influenzae should be
considered resistant to :-
 Ampicillin-Sulbactam
 Amoxacillin-Clavulanic acid
 Cefuroxime
 piperacillin-tazobactam
 Cefaclor
 Cefetamet
 Cefonicid
 cefprozil
 Loracarbef

12. • Chloramphenicol not routinely reported on
isolates of urinary tract.
• Rifampicin should not be used alone for
antimicrobial therapy

13. Drug Conc. Of Drug used H. Enterobacteriacae
µm Influenzae
Ampicillin 10 22 17
Ampillin-Sulbactam 10/10 20 15
Amoxicillin- 20/10 20 18
Clavulanic acid
Piperacillin- 100/10 21 21
Tazobactam
Cefotaxime or 30 26 26
Ceftazidime or 30 26 21
Ceftriaxone 30 26 23
Cefuroxime 30 20 18
Cefpodoxime 10 21 21

14. Drug Conc. Of Drug used H.influenzae Enterobacteriacae
µm
Cefepime 30 26 18
Ciprofloxacin or 5 18 21
Levofloxacn or 5 16 17
Ofloxacin 5 18 16
Trimethoprim- 1.25/23.75 16 16
Sulfamethoxazole
Chloramphenicol 29 18
30
Meropenem 10 20 23

15. Drug Conc. Of Drug used H. Enterobacteriacae
µm Influenzae
Tetracycline 30 29 15
Imipenem or 10 16 23
Etrapenem 10 19 23
Azithromycin or 15 12 _
Clarithromycin 15 13 _
Gatifloxacin 5 18 15
Rifampin 5 20 _

16. NEISSERIA GONORRHOEAE

17. TESTING CONDITIONS
• Medium:
 Disk Diffusion: GC agar base and 1% defined
growth supplement
 Agar dilution: GC agar base and 1%
defined growth
supplement

18. GC agar supplement
 1.1g L-cysteine
 0.03g guanine HCL
 3 mg thiamine HCL
 13 mg para-aminobenzoic acid[PABA]
 0.1 g B12
 0.1 g cocarboxylase
 0.25 g NAD
 1 g adenine
 10 g L-glutamine
 100 g glucose
 0.02 g ferric nitrate[in 1 L H2O]

19. TESTING CONDITIONS
• Inoculum:
Direct colony suspension, equivalent
to a 0.5 McFarland standard
• Incubation: 36±1 0c, 5% CO 2,
20 to 24 hours

20. MINIMAL QC Recommendations
Neisseria gonorrhoeae ATCC 49226

21. Suggested grouping of antimicrobial agents that should be
considered for routine testing and reporting for Neisseria
gonorrhoeae
• GROUP C (SUPPLEMENTAL)-REPORT SELECTIVELY
 Cefixime or Cefpodoxime
 Cefotaxime or ceftriaxone
 Cefoxitin
 Cefuroxime
 Ciprofloxacin or Ofloxacin
 Penicillin
 Spectinomycin
 Tetracycline

22. single dose treatment regimen for
Neisseria gonorrhoeae
Ceftriaxone (125 mg IM)
Cefixime (400mg PO)
Ciprofloxacin (500 mg PO)
Ofloxacin (400 mg PO)
Levofloxacin (250 mg PO)

23. Standard Zone diameters for AST of Neisseria
gonorrhoeae
Drug Conc. Of drug µm Zone
Penicillin 10 units 47
Cefotaxime or 30 31
Ceftriaxone 30 35
Cefoxitin 30 28
Cefepime 30 31
Ceftazidime 30 31
Cefpodoxime 10 29
Tetracycline 30 38
Ciprofloxacin or 5 41
ofloxacin 5 31