Exam 4 Study guide 

TB  phases pg 542
1.	Transmission- *airborne particles* are exhaled and infected person and inhaled by uninfected person 
2.	Primary infection – estimated that 30% of people exposed to TB become infected and develop a mild, pneumonia-like illness that is often undiagnosed. About 6-8 wks after exposure positive reaction to TB skin test. Within about 6 months of exposure, spontaneous healing occurs as the bacilli are encapsulated in calcified tubercles.  
3.	*Latent TB infection (LTBI) – immune system is able to stop bacterial growth in most. Bacteria  become inactive but remain alive in the body and can later become active. No symptoms, do not feel sick, do not spread TB to others, usually positive skin-test reaction.
4.	*Active TB- TB bacteria usually becomes active and causes TB when a person’s immune system becomes weak as result of a disease, immunosuppressive drugs or aging. 

TB drugs 
*drug compliance is a huge problem*

Isoniazid

Most common Isoniazid (INH) 
Nontoxic , bacterialcial, ralativley inexpensive can be given orally or by injection
Serious side effects* hepatotoxicity * and peripheral neuropathy 
Broad spectrum 

Rifamipin

Bacterialcidal 
Adverse side effects GI upset, skin rashes, hepatitis, and a harmless red-orange discoloration of urine, tears and swear and other body fluids. 
P450 pathway
Can decrease the effects of ACE inhibitors, anticoagulants, antidysrhmics, some antifungal eg. Fluconazole( there is very long list of drugs interacts with pg 554)

Treatment o f active TB

Improvement  within 2 to 3 wks, decreased fever and  cough, weight gain, improved chest radiographs.
Treatment should be continued for at least 6 to 3 months after cultures become negative.

INH, rifampin and pyrazinemide daily or twice weekly for 2 months then the pyrazinamide is stopped and the others are continued for 4 additional months
  
INH , rifampin and pyrazinemide can all cause liver damge thus should avoid alcohol and watch for signs of hepatitis  ( nausea, and yellowing of the skin or eyes and darkening of the urine)
For Isoniazide (INH) resistant TB the recommended regimen is rifampin, pyrazinamide, and ethambutol for 6 months 

Fluroquinolones
Not much here pg 550 (last para above treatment of active TB)
Fluroquinolones
They include ciprofloxacin and levofloxacin 
These drugs are not usually considered antitubercular drugs, they have activity against mycobacteria and be a component of a four-to –six drug regimen to treat suspected or known MDR-TB (multidrug-resistant TB) 

General info on TB treatment

Multiple drugs are required to effectively treat

Typical treatment is given over 6 months but if interrupted it is to given be within a max of 9 months

MDR-TB requires more drugs and longer treatment length than drug –susceptible TB , four to six drugs and for a period of 2yrs or longer

HIV
*HIV patients do not give live vaccines * 

HIV therapy

*HARRT (highly active antiretroviral therapy) 
Not a cure, but a slow progression very expensive*
Goal of therapy decreasing viral load ( less than 400 copies/ml) restore immune function, halt disease progression . 

Viral load- measure of number HIV RNA particles within the blood; it does not measure viral levels in tissues, where viral replication reproduction may be continuing  

A degree of adherence is required because lack of adherence may lead to lack of effectiveness an emergence of drug-resistant viral strands. 

NOT recommended to take herbal products with antiretroviral med. St. John’s wart decrease blood levels of some anti-HIV meds. Echinacea stimulates viral replication. Do not take abacavir or efavirenz with high-fat meal. 

Combination antiretroviral therapy is standard of care. commonly used three-drug regimen includes two nucleoside reverse transcriptase inhibitors (NRTIs) and a non-nucleoside reverse transcriptase inhibitor (NNRTI) (most commonly efavirenz) or three NRTIs

Diflucan

Fluconazole (Diflucan )

Indications: oropharyngeal, esophageal, vaginal, and systemic, candidaisis, cryptococcal meningitis

Drug of choice for localized candidal infections and useful for systemic candidaisis but with extensive use drug resistance occurs  
Single dose for vaginal candidiasis
Can be given orally or by IV

Usually well tolerated may cause nausea, vomiting, diarrhea, abdominal pain, headache, and skin rash.

Drug interactions

Increases the effects of several drugs: cyclosporine, phenytoin, oral sulfonylureas, and warfarin