drugs for tuberculosis and mycobacterium avium complex disease l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Drugs for Tuberculosis and Mycobacterium avium complex disease PowerPoint Presentation
Download Presentation
Drugs for Tuberculosis and Mycobacterium avium complex disease

Loading in 2 Seconds...

play fullscreen
1 / 52

Drugs for Tuberculosis and Mycobacterium avium complex disease - PowerPoint PPT Presentation


  • 340 Views
  • Uploaded on

Drugs for Tuberculosis and Mycobacterium avium complex disease. NUR 3703 Pharmacology By Linda Self. History. Dates back to ancient Egypt and Babylonia “consumption” Sanitoriums Robert Koch in 1905 Development of BCG in 1924 Streptomycin 1943. Mycobacterium tuberculosis.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Drugs for Tuberculosis and Mycobacterium avium complex disease' - jacob


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
drugs for tuberculosis and mycobacterium avium complex disease

Drugs for Tuberculosis and Mycobacterium avium complex disease

NUR 3703

Pharmacology

By Linda Self

history
History
  • Dates back to ancient Egypt and Babylonia
  • “consumption”
  • Sanitoriums
  • Robert Koch in 1905
  • Development of BCG in 1924
  • Streptomycin 1943
mycobacterium tuberculosis
Mycobacterium tuberculosis
  • Gram positive mycobacterium
  • Divides slowly, only q15-20h
  • Can withstand weak disinfectants
  • Can survive in dry state for weeks
  • Must grow within a host organism
slide4
TB
  • Infectious disease caused by tubercle bacillus
  • 80% affect lungs
  • Multiplies slowly
  • Can lie dormant
slide5
TB
  • Identified microscopically by staining characteristics
  • Retains certain stains thus “acid-fast”
  • Can now obtain results of blood test within 24h—Quantiferon TB gold test (must follow specific guidelines for obtaining test sample)
slide6
TB
  • Occurrence had waned
  • Now resurgence due to international travel, persons with depressed immune systems (medications and conditions), emergence of AIDS
  • Incidence has been increasing since 1986
slide7
TB
  • Untreated, two of every three individuals with active disease will die
  • With treatment, mortality less than 5%
epidemiology
Epidemiology
  • Transmission—inhalation
  • Contributors: number of bacteria, closeness and duration of contact
  • Primary infection-30% exposed will become infected. Dormant until optimal conditions. Will test positive to PPD.
  • Latency-no symptoms but bacteria are there
epidemiology9
Epidemiology
  • Active tuberculosis—reactivation of latent infection although new infection can also occur
  • Occurs more often in those with depressed immunity
  • Among people with both latent TB and HIV infection, latent TB will progress more rapidly, is more severe and is often extrapulmonary
drug resistant tb
Drug Resistant TB
  • Multiple drug therapy
  • Clinical monitoring monthly
  • Lab testing—obtain baseline. In populations with liver disease, will check liver function studies monthly. May have to stop INH if transaminase levels greater than 3 times upper limit of normal if s/s, to 5 times normal if no s/s
drug resistance
Drug Resistance
  • One of biggest contributors to this development is those who are not adherent
high risk groups
High Risk Groups
  • Should test certain groups which are at higher risk for developing active tuberculosis
  • Immigration from areas of world w/high incidence
  • Homeless
  • Injection drug user
  • Chronic renal failure
  • Diabetes mellitus
  • High dose steroids
high risk groups13
High Risk Groups
  • HIV infection or AIDS
  • Chest xray with fibrotic lesions
  • Cachexic
  • Silicosis
  • Older groups who reside in congregate settings
  • Young children who test positive
clinical manifestations
Clinical Manifestations
  • Weight loss
  • Anorexia
  • Malaise
  • Fever
  • Productive cough
  • Night sweats
  • Older adults s/s less prominent; in children, resembles pneumonia
testing
Testing
  • Health centers
  • Medical clinics
  • Homeless shelters
  • Jails
  • Methadone clinics
  • Businesses
  • institutions
slide16
How?
  • PPD
  • Aplisol, Aplitest, Tine test
  • Sterile isotonic solution of tuberculin
  • Intradermally injected
  • Spurs immune response
  • Should be interpreted in 48-72h
  • Anergy is an issue
test interpretation
Test Interpretation

Induration of 5 mm or more deemed positive in those with HIV, w/risk factors for HIV, those with chest xrays consistent with previous TB, in those who have had close contact with someone with active TB

  • Organ transplants
  • Those on high dose steroids or on TNF antagonists
test interpretation18
Test Interpretation

Induration of 10mm or more—positive in those at high risk such as immigrants, residents and employees of prisons, children exposed to adults in high risk groups

  • Chronic renal failure
  • Gastrectomy patients
  • IV drug users
  • Possibly cancer
test interpretation19
Test Interpretation
  • Induration of 15mm or more-essentially all others
test interpretation20
Test Interpretation
  • False positives-may occur in those who have had BCG (from Mycobacterium bovis)
  • False negatives in those with anergy
slide21
BCG
  • Bacillus Calmette-Guerin
  • Vaccine developed from Mycobacterium bovis—lost virulence in humans secondary to engineering of the bacillus
  • Variable effectiveness, up to 15 years
  • May cloud reliability of PPD
  • Also useful in bladder cancer, leprosy
preliminaries before treatment
Preliminaries Before Treatment
  • Thorough history
  • Complete physical
  • Chest xray
  • Sputum studies
  • Baseline labs (liver enzymes, bili, CBC, lytes)
primary antitubular drugs
Primary Antitubular Drugs

Isoniazid (INH)

  • Prototype of antituberculars
  • Bactericidal
  • Inhibits cell wall synthesis
  • Acetylators a consideration—slow, more prone to toxicity; rapid, may need larger dose
isoniazid inh
Isoniazid (INH)
  • Penetrates body cells and mycobacteria
  • Inhibits growth of dormant organisms in macrophages
inh side effects
INH Side Effects
  • Hepatotoxicity
  • Peripheral neuropathies
  • Pyridoxine is usually given with INH to minimize peripheral neuropathy
rifampin
Rifampin

Rifamycin

  • Bactericidal for intracellular and extracellular organisms
  • Inhibits synthesis of RNA so causes defective proteins to be produced
  • Synergistic with INH
  • Produces clinical improvement faster than any other drug regimen unless resistance is present
rifampin27
Rifampin
  • Diffuses well into tissues
  • Rapid oral absorption
  • Metabolized in liver, excreted in bile
  • Causes harmless red-orange discoloration of body fluids
rifampin adverse effects
Rifampin Adverse Effects
  • GI upset
  • Skin rashes
  • Hepatitis
  • Drug interactions
  • Accelerates metabolism of some drugs
  • See p. 554
rifabutin
Rifabutin

Another rifamycin

  • Works like rifampin
  • Main uses are in those with HIV infection, in MAC and to substitute for rifampin in those who need both antitubercular and certain antiviral medications
  • Advantages are its longer serum half-life and reduced hepatic induction of metabolyzing enzymes
rifabutin30
Rifabutin

Causes:

  • Discoloration of body fluids
  • GI upset
  • Hepatitis
  • Muscular aches
  • Neutropenia
  • Skin rash
  • Uveitis
  • Rare hepatotoxicity
ethambutol
Ethambutol

Tuberculostatic drug that inhibits synthesis of RNA and thus, protein synthesis

  • Not recommended in young children (under 5)
  • Well absorbed in GI tract
  • Total daily dosage is given at one time
  • Can affect renal function
  • Can cause optic neuritis
pyrazinamide
Pyrazinamide
  • Used with INH and rifampin for first two months of treating active TB and possibly as single agent for four months in those with LTBI
  • Pyrazinamide is contraindicated in pregnancy
pyrazinamide33
Pyrazinamide
  • Bactericidal but mechanism is unclear
  • Good GI absorption
  • Rapid onset, peaks in two hours
  • Metabolized by liver, excreted by kidneys
pyrazinamide34
Pyrazinamide

Can cause:

  • Hepatotoxicity
  • Inhibits urate excretion
  • Not to be used in liver compromise
  • Monitor liver enzymes every 2 weeks during course of Tx (usually 8 weeks)
streptomycin
Streptomycin

Aminoglycoside

  • Does not penetrate macrophages and tuberculous lesions
  • May be used in multi-drug therapy
drugs in multidrug resistant tuberculosis
Drugs in Multidrug Resistant Tuberculosis

MDR means the TB is resistant to at least two of the first line medications (INH, RIF, PZA, Ethambutol) so add:

  • Amikacin
  • Kanamycin
  • fluoroquinolones
for exceptionally drug resistant tb
For exceptionally drug resistant TB
  • Resistance present to INH, RIF, PZA, ethambutol will use quinolones and at least one of three injectable drugs (amikacin, Kanamycin and capreomycin)
rif pza
RIF-PZA
  • Caution in those taking other hepatotoxic drugs or who use alcohol
  • Recommended in those who are unlikely to complete longer courses of Tx and who can be monitored closely
  • Perform LFTs at baseline and at 2,4, 6 weeks. Stop if levels are higher than five times the upper limit, if s/s hepatitis are present or if bilirubin is elevated
second line drugs
Second Line Drugs
  • Para-aminosalicyclic acid
  • Capreomycin
  • Cycloserine
  • ehtionamide
active tb
Active TB
  • Different regimens
  • Dosing most important element
  • Combination therapy
  • INH, Rifampin, and pyrazinamide daily for 2 months followed by INH and Rifampin for 4 additional months
  • If resistance in community, should add fourth drug such as ethambutol or streptomycin until susceptibility reports are available
inh resistant tb
INH Resistant TB
  • Rifampin, pyrazinamide, and ethambutol for 6 months
treatment of latent tuberculosis infection
Treatment of Latent Tuberculosis Infection
  • INH daily or twice weekly for 9 months incl. those with HIV infection or xray evidence of prior TB
  • INH daily or twice weekly for 6 mos. Less costly. Okay in HIV negative adults with normal chest xrays. Not in HIV, <18 yo or those with fibrotic lesions on chest films.
treatment of ltbi
Treatment of LTBI
  • RIF and PZA daily or twice weekly for 2 months. Indicated in those in contact with INH resistant TB and for those unlikely to complete a longer course of Tx.
special populations
Special Populations
  • Pregnancy—INH daily or twice weekly for 6-9 months. Take B6. INH, rifampin, and ethambutol relative safety. Pyrazinamide and streptomycin are contraindicated.
special populations45
Special Populations
  • Children and adolescents. INH daily or twice weekly for 9 months is optimum. Infants and children under 5 are at high risk for progression of disease.
  • INH more effective in children than adults
  • Risk for INH hepatitis in children is small
  • Felt not necessary for B6 supplementation
special populations46
Special Populations
  • Can’t use rifampin in people being treated with PIs or NNRTIs. May substitute Rifabutin, in one half the dose, unless patient is taking delavirdine or saquinavir.
treatment
Treatment
  • When INH and rifampin cannot be given because of resistance, drug therapy should continue for 24 months after sputum smears or cultures become negative
  • Cannot use fluoroquinolones in children
treatment48
Treatment

Older adults:

  • Treatment may be based on both PPD and other factors
  • INH hepatotoxic in elderly
  • Active disease-- INH, rifampin and pyrazinamide are given cautiously
  • Closely monitor liver function
treatment49
Treatment
  • Tailor to the circumstances, allow patient participation in selecting treatment
  • Directly Observed Therapy (DOT) should be used consistently with intermittent regimens, in those who are high risk for non-adherence and in institutional settings
  • Ensure completion of therapy by determining both total time and number of doses of medication taken
monitoring antitubercular therapy
Monitoring Antitubercular Therapy
  • Clinical monitoring is indicated for all patients.
  • Monitor for s/s of liver disease such as: dark urine, jaundice, numbness or tingling of hands or feet, jaundice, vomiting, loss of appetite, abdominal tenderness, bruising or bleeding.
  • Lab monitoring. Stop INH if LFTs 3x normal with s/s or 5x normal if no s/s.
mycobacterium avium complex
Mycobacterium avium complex
  • Comprised of either mycobacterium avium or mycobacterium intracellulare
  • Closely resemble each other
  • Found in water and soil
  • Transmitted by inhalation of droplets of contaminated water
slide52
MAC
  • Rarely affects immunocompetent people
  • Is opportunistic
  • S/S: productive cough, weight loss, hemoptysis, fever to dissemination
  • Preventive drugs are macrolides and rifabutin
  • Need lifelong prophylaxis