Lehne Chapter 90 TB DRUGS

A patient newly diagnosed with tuberculosis asks the nurse why oral medications must be given in the clinic. The nurse will tell the patient that medications are given in the clinic so that: a. clinic staff can observe adherence to drug regimens. b. nurses can monitor for drug toxicities. c. providers can adjust doses as needed. d. the staff can ensure that the U.S. Food and Drug Administration (FDA) regulations are met.

ANS: A Adherence to drug regimens is a serious problem in the treatment of TB. Directly observed therapy (DOT) combined with intermittent dosing helps ensure adherence and increases the chance of success. Patients report drug side effects to providers; it is not necessary to give drugs in the clinic to monitor this. Doses are adjusted based on response to treatment and not on DOT. The FDA regulations do not require DOT.

A patient is about to begin therapy with ethambutol. The nurse knows that, before initiating treatment with this drug, it is important to obtain which test(s)? a. Color vision and visual acuity b. Complete blood cell (CBC) count c. Hearing testing and a tympanogram d. Hepatic function tests

ANS: A Optic neuritis is a dose-related adverse effect of ethambutol. Patients receiving this drug should have color vision and visual acuity testing before therapy starts and periodically thereafter. A CBC, hearing evaluations, and hepatic function testing are not recommended.

A patient with HIV who takes protease inhibitors develops tuberculosis and will begin treatment. Which drug regimen will be used for this patient? a. Isoniazid, pyrazinamide, ethambutol + rifabutin b. Isoniazid, pyrazinamide, ethambutol c. Isoniazid, rifampin, pyrazinamide, ethambutol d. Isoniazid + rifabutin

ANS: A Patients with HIV who take protease inhibitors are susceptible to drug interactions with rifampin, which accelerates the metabolism of protease inhibitors. Rifabutin can be substituted for rifampin in patients with HIV, because the degree of acceleration of this metabolism is less. A three-drug regimen would increase drug resistance, as would a two-drug regimen.

A hospitalized patient is being treated for tuberculosis with a drug regimen that includes pyrazinamide. The patient complains of pain in the knee and shoulder joints. The nurse will contact the provider to request an order for: a. ibuprofen. b. renal function tests. c. discontinuation of the pyrazinamide. d. measurement of uric acid levels.

ANS: A Polyarthralgias occur in 40% of patients during the initial phase of treatment with pyrazinamide and can be managed with a nonsteroidal anti-inflammatory drug (NSAID). Renal function tests and uric acid levels are not indicated. Unless the pain cannot be managed with NSAIDs, there is no need to reduce the dose of pyrazinamide.

A patient with high-risk factors for tuberculosis will begin therapy for latent TB with isoniazid and rifampin. The nurse learns that this patient takes oral contraceptives. The nurse will counsel this patient to discuss ____ with her provider. a. another birth control method b. reducing the rifampin dose c. reducing the isoniazid dose d. increasing the oral contraceptive dose

ANS: A Rifampin induces cytochrome P450 enzymes and can accelerate the metabolism of many drugs, including oral contraceptive pills (OCPs). Women taking OCPs should consider a nonhormonal form of birth control. Reducing the dose of rifampin or isoniazid is not indicated. Increasing the OCP dose is not recommended.

A nursing student asks a nurse why tuberculosis resistance is so high. Which reasons are correct? (Select all that apply.) a. Adherence to drug regimens is erratic. b. Drug doses are often too low. c. Many hosts are immunocompromised. d. Many regimens contain too few drugs. e. Some TB drugs are bacteriostatic.

ANS: A, B, D There are many reasons for the emergence of drug-resistant organisms in the treatment of TB. They include erratic patient adherence, drug doses that are too low, and drug regimens with too few drugs. The immunocompetence of the host does not affect drug resistance, nor does the fact that some agents are bacteriostatic.

Which patient should begin treatment for tuberculosis? a. A patient with HIV and a tuberculin skin test result of a 4-mm region of induration b. A recent immigrant from a country with a high prevalence of TB with a 10-mm region of induration c. A patient with no known risk factors who has a job-related tuberculin skin test result of a 12-mm area of induration d. An intravenous drug abuser with a tuberculin skin test result of a 5-mm region of induration

ANS: B The immigrant is considered to be at moderate risk, meaning that a 10-mm area of induration on a tuberculin skin test (TST) is considered a positive result. After being evaluated for active TB, this patient should be treated for latent TB. A patient with HIV is considered high risk, but this patient has a negative TST result of less than 5 mm. For a low-risk patient receiving a screening TST for a job, the area of induration must be 15 mm or greater to be considered a positive result. An IV drug abuser is in the moderate-risk category; an area of induration of 10 mm or greater is needed to be considered a positive TST result.

Which patient(s) should be tested for latent TB? (Select all that apply.) a. A day care employee b. A worker in a mycobacteriology laboratory c. A patient with cardiovascular disease d. A patient with diabetes mellitus e. An immigrant from a country where TB is prevalent

ANS: B, D, E Testing should be limited to people who are at high risk of either having acquired TB recently or who might be progressing from latent to active TB. People who work in mycobacteriology laboratories work with TB and are at risk. Patients with some debilitating diseases, such as diabetes mellitus, are at risk. Immigrants from countries where TB is prevalent are at risk. Employees of day care centers and patients with cardiovascular disease are not at increased risk.

A patient has been taking isoniazid [Nydrazid] for 4 months for latent tuberculosis. The patient reports bilateral tingling and numbness of the hands and feet, as well as feeling clumsy. The nurse expects the provider to: a. discontinue the isoniazid. b. lower the isoniazid dose and add rifampin. c. order pyridoxine 100 mg per day. d. recheck the tuberculin skin test to see whether it worsens.

ANS: C Patients sometimes develop peripheral neuropathy, characterized by paresthesias, clumsiness, and muscle aches. If these occur, they may be reversed by administering pyridoxine (vitamin B6). It is not necessary to discontinue the isoniazid. Lowering the isoniazid dose and adding rifampin is not indicated. Rechecking the TST is not indicated.

A patient is about to begin treatment with isoniazid. The nurse learns that the patient also takes phenytoin [Dilantin] for seizures. The nurse will contact the provider to discuss: a. increasing the phenytoin dose. b. reducing the isoniazid dose. c. monitoring isoniazid levels. d. monitoring phenytoin levels.

ANS: D Isoniazid is a strong inhibitor of three cytochrome P450 enzymes, and inhibition of these enzymes can raise the levels of other drugs, including phenytoin. Patients taking phenytoin should have the levels of this drug monitored, and the dose should be reduced if appropriate. Reducing the dose of isoniazid is not indicated. It is not necessary to monitor isoniazid levels.

A patient is beginning treatment for active tuberculosis (TB) in a region with little drug-resistant TB. Which treatment regimen will be used initially? a. Isoniazid and pyrazinamide b. Isoniazid, pyrazinamide, and ethambutol c. Rifampin, pyrazinamide, and ethambutol d. Isoniazid, rifampin, pyrazinamide, and ethambutol

ANS: D The induction phase of treatment for patients in a region without drug resistance is the same as for patients who are human immunodeficiency virus (HIV) negative or HIV positive and includes isoniazid, rifampin, pyrazinamide, and ethambutol. It is not correct to begin with two drugs. The three-drug regimen is used for inductions in areas with resistance to either isoniazid or rifampin.

A nurse is performing a physical assessment on a patient with tuberculosis who takes rifampin [Rifadin]. What would be an expected finding? a. Crystalluria b. Myopathy c. Peripheral neuropathy d. Red-orange-tinged urine

ANS: D Urine tinged red-orange is a normal finding associated with rifampin's adverse effects. Peripheral neuropathy, myopathy, and crystalluria are not manifestations of adverse effects of rifampin.

RIPE (TB TREATMENT)

Isoniazid, rifampin, pyrazinamide, ethambutol