Dynacin (Page 2 of 4)

A report of “Susceptible” indicates that the pathogen is likely to be inhibited if the antimicrobial compound in the blood reaches the concentrations usually achievable. A report of “Intermediate” indicates that the result should be considered equivocal, and, if the microorganism is not fully susceptible to alternative, clinically feasible drugs, the test should be repeated. This category implies possible clinical applicability in body sites where the drug is physiologically concentrated or in situations where high dosage of drug can be used. This category also provides a buffer zone which prevents small uncontrolled technical factors from causing major discrepancies in interpretation. A report of “Resistant” indicates that the pathogen is not likely to be inhibited if the antimicrobial compound in the blood reaches the concentrations usually achievable; other therapy should be selected.

Standardized susceptibility test procedures require the use of laboratory control microorganisms to control the technical aspects of the laboratory procedures. Standard tetracycline powder should provide the following MIC values:

Microorganism MIC Range (µg/mL)
Escherichia coli ATCC 25922 0.5–2.0
Enterococcus faecalis ATCC 29212 8.0–32.0
Staphylococcus aureus ATCC 29213 0.25–1.0
Haemophilus influenzae ATCC 49247 4.0–32.0
Streptococcus pneumoniae ATCC 49619 0.12–0.5
Neisseria gonorrhoeae ATCC 49226 0.25–1.0

Diffusion techniques

Quantitative methods that require measurement of zone diameters also provide reproducible estimates of the susceptibility of bacteria to antimicrobial compounds. One such standardized procedure2,3 requires the use of standardized inoculum concentrations. This procedure uses paper disks impregnated with 30µg tetracycline (class disk) or 30µg minocycline to test the susceptibility of microorganisms to minocycline. Reports from the laboratory providing results of the standard single-disk susceptibility test with a 30µg tetracycline or minocycline disk should be interpreted according to the following criteria:

For testing aerobic gram-negative microorganisms (Enterobacteriaceae) Acinetobacter ssp. and Staphylococcus aureus:

Zone Diameter (mm) Interpretation
≥ 19 Susceptible (S)
15–18 Intermediate (I)
≤ 14 Resistant (R)

For testing Haemophilus influenzae d:

Zone Diameter (mm) Interpretation
≥ 29 Susceptible (S)
26–28 Intermediate (I)
≤ 25 Resistant (R)

d These zone diameter standards are applicable only to susceptibility testing with Haemophilus influenzae using Haemophilus Test Medium and a 30µg tetracycline disk.2

For testing Neisseria gonorrhoeae e:

Zone Diameter (mm) Interpretation
≥ 38 Susceptible (S)
31–37 Intermediate (I)
≤ 30 Resistant (R)

e These interpretative standards are applicable only to disk diffusion testing using GC agar and 1% growth supplements, and a 30µg tetracycline disk.2

For testing Streptococcus pneumoniae f:

Zone Diameter (mm) Interpretation
≥ 23 Susceptible (S)
19–22 Intermediate (I)
≤ 18 Resistant (R)

f These interpretative standards are applicable only to disk diffusion testing using Muller-Hinton agar adjusted with 5% sheep blood and a 30µg tetracycline disk.2

For testing Vibrio cholerae g:

Zone Diameter (mm) Interpretation
≥ 19 Susceptible (S)
15–18 Intermediate (I)
≤ 14 Resistant (R)

g These interpretative standards are applicable only to disk diffusion testing performed with a 30µg tetracycline disk.2

Interpretation should be as stated above for results using dilution techniques. Interpretation involves correlation of the diameter obtained in the disk test with the MIC for tetracycline.

As with standardized dilution techniques, diffusion methods require the use of laboratory control microorganisms that are used to control the technical aspects of the laboratory procedures. For the diffusion technique, the 30µg tetracycline or minocycline disk should provide the following zone diameters in these laboratory test quality control strains:

Microorganism Zone Diameter Range (mm)
Tetracycline Minocycline
Escherichia coli ATCC 25922 18–25 19–25
Staphylococcus aureus ATCC 25923 24–30 25–30
Haemophilus influenzae ATCC 49247 14–22
Neisseria gonorrhoeae ATCC 49226 30–42
Streptococcus pneumoniae ATCC 49619 27–31

INDICATIONS AND USAGE

Minocycline Hydrochloride Capsules are indicated in the treatment of the following infections due to susceptible strains of the designated microorganisms:

Rocky Mountain spotted fever, typhus fever and the typhus group, Q fever, rickettsialpox and tick fevers caused by Rickettsiae
Respiratory tract infections caused by Mycoplasma pneumoniae
Lymphogranuloma venereum caused by Chlamydia trachomatis
Psittacosis (Ornithosis) due to Chlamydia psittaci
Trachoma caused by Chlamydia trachomatis , although the infectious agent is not always eliminated, as judged by immunofluorescence
Inclusion conjunctivitis caused by Chlamydia trachomatis
Nongonococcal urethritis, endocervical, or rectal infections in adults caused by Ureaplasma urealyticum or Chlamydia trachomatis
Relapsing fever due to Borrelia recurrentis
Chancroid caused by Haemophilus ducreyi
Plague due to Yersinia pestis
Tularemia due to Francisella tularensis
Cholera caused by Vibrio cholerae
Campylobacter fetus infections caused by Campylobacter fetus
Brucellosis due to Brucella species (in conjunction with streptomycin)
Brucellosis due to Bartonella bacilliformis
Granuloma inguinale caused by Calymmatobacterium granulomatis

Minocycline is indicated for treatment of infections caused by the following gram-negative microorganisms, when bacteriologic testing indicates appropriate susceptibility to the drug:

Escherichia coli
Enterobacter aerogenes
Shigella
species
Acinetobacter
species
Respiratory tract infections caused by Haemophilus influenzae
Respiratory tract and urinary tract infections caused by Klebsiella species

Minocycline hydrochloride capsules are indicated for the treatment of infections caused by the following gram-positive microorganisms when bacteriologic testing indicates appropriate susceptibility to the drug:

Upper respiratory tract infections caused by Streptococcus pneumoniae
Skin and skin structure infections caused by Straphylococcus aureus.
(Note: Minocycline is not the drug of choice in the treatment of any type of staphylococcal infection.)

When penicillin is contraindicated, minocycline is an alternative drug in the treatment of the following infections:

Uncomplicated urethritis in men due to Neisseria gonorrhoeae and for the treatment of other gonococcal infections when penicillin is contraindicated.
Infections in women caused by Neisseria gonorrhoeae
Syphilis caused by Treponema pallidum subspecies pallidum
Yaws caused by Treponema pallidum subspecies pertenue
Listeriosis due to Listeria monocytogenes
Anthrax due to Bacillus anthracis
Vincent’s infection caused by Fusobacteruim fusiforme
Actinomycosis caused by Actinomyces israelii
Infections caused by Clostridium species

In acute intestinal amebiasis , minocycline may be a useful adjunct to amebicides.

In severe acne , minocycline may be useful adjunctive therapy.

Oral minocycline is indicated in the treatment of asymptomatic carriers of Neisseria meningitidis to eliminate meningococci from the nasopharynx. In order to preserve the usefulness of minocycline in the treatment of asymptomatic meningococcal carriers, diagnostic laboratory procedures, including serotyping and susceptibility testing, should be performed to establish the carrier state and the correct treatment. It is recommended that the prophylactic use of minocycline be reserved for situations in which the risk of meningococcal meningitis is high.

Oral minocycline is not indicated for the treatment of meningococcal infection.

Although no controlled clinical efficacy studies have been conducted, limited clinical data show that oral minocycline hydrochloride has been used successfully in the treatment of infections caused by Mycobacterium marinum.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of minocycline hydrochloride capsules and other antibacterial drugs, minocycline hydrochloride capsules should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

All MedLibrary.org resources are included in as near-original form as possible, meaning that the information from the original provider has been rendered here with only typographical or stylistic modifications and not with any substantive alterations of content, meaning or intent.

This site is provided for educational and informational purposes only, in accordance with our Terms of Use, and is not intended as a substitute for the advice of a medical doctor, nurse, nurse practitioner or other qualified health professional.

Privacy Policy | Copyright © 2022. All Rights Reserved.