ANTIBIOTICS 1 Acute Bronchitis l FA a 35

ANTIBIOTICS 1

Acute Bronchitis l FA, a 35 -year-old woman, presents with a persistent cough following an acute respiratory viral infection that began seven days ago. Although the nasal stuffiness and sore throat resolved three or four days ago, the cough has persisted and her sputum has become thick and mucoid in appearance. A burning substernal pain is associated with each coughing episode. FA is afebrile. Coarse rales and rhonchi are heard on physical examination of her chest and a tentative diagnosis of acute bronchitis is made. 2

Question: l What are the usual causes of acute bronchitis? 3

Answer: l Infectious causes of acute bronchitis are primary viral 4

Question: l Most healthy adults with typical symptoms of bronchitis do not require diagnostic evaluation. What are symptoms which may require a more extensive diagnostic evaluation? 5

Answer: l Fever, profound constitutional symptoms, dyspnea, rigors or pleuritc chest pain. 6

Question: l What is the treatment of acute bronchitis? 7

Answer: l The treatment of acute bronchitis is directed at symptomatic control of cough, maintenance of hydration and the intermittent administration of antipyretics to reduce constitutional symptoms. Although antibiotics prescribed for acute bronchitis account for 7 million prescriptions annually (11% of all antibiotic prescriptions in the US), they are not indicated for the majority of patients with acute bronchitis. This practice is a major source of antibiotic abuse. Patients whose coughs are severe or prolonged (greater than 14 d) or who have fever may be candidates for antibiotic therapy. 8

CHRONIC BRONCHITIS l MJ, a 54 -year-old man with a 40 -year, 1 -pack/day smoking history, has a 7 -year history of emphysema. He reports two cupfuls of whitish-clear, occasionally mucoid sputum per day; he coughs up the largest volumes in the morning upon arising. MJ has a raspy voice and crackling cough, which often interrupts his talking. Two days ago, he noticed that his sputum had increased in volume and had changed in appearance. A sputum sample, which was yellowish-green, tenacious and obviously purulent, was sent for culture; the Gram stain showed moderate white cells, and a few Gram-positive cocci and Gram-negative rods with no predominant organisms. MJ denies fever or chills. The chest X-ray is negative for pneumonia. MJ experiences similar episodes three or four times per year. 9

Question: l What is the definition of chronic bronchitis? 10

Answer: l Daily sputum production over three or more consecutive months for greater than two successive years. 11

Question: l Should MJ be given antibiotics to treat his acute episode of bronchitis? 12

Answer: l The American Thoracic Society’s guidelines regarding the management of exacerbations of chronic bronchitis state “Although antibiotics have been used extensively for years to treat acute exacerbations of chronic bronchitis, as well as for prophylaxis in stable bronchitis, their value for either purpose has not been established. Mild to moderately ill patients without pneumonia, such as MJ, usually do not require antibiotics to treat exacerbations of chronic bronchitis. ” 13

Question: l MJ does not improve after 3 days, despite postural drainage exercises and hydration. How should he be managed? 14

Answer: l An antibiotic effective against S. pneumoniae and H. influenzae should be prescribed. Standard treatment includes amoxicillin 250 mg or 500 mg tid, doxycycline 100 mg bid or TMP-SMX (Bactrim DS) bid for ten days. The use of new agents including clarithromycin, azithromycin and the fluroquinolones, should be effective for treating acute exacerbations. However, none of these agents have been demonstrated to be superior to more established treatments and THEY ARE MARKEDLY MORE EXPENSIVE! The indiscriminate use of antibiotics should be discouraged. 15

Question l Would prophylactic antibiotics be useful in MJ? 16

Answer l Prophylactic antibiotic therapy decreases the number of acute exacerbations of bronchitis in patients with frequent episodes, but it has not been helpful in patients such as MJ with infrequent exacerbations. If necessary, they should be used only during critical periods when patients are most susceptible. For example, daily doses of antibiotics four days a week during the winter months or a seven-day course of antibiotics at the first sign of a “chest cold” have been suggested. 17

Question: l Should MJ receive both the flu vaccine and the pneumococcal vaccine? If so, how often should they be administered? 18

Answer l The flu vaccine should be administered annually and the pneumococcal vaccine should be administered once, with possible re -administration in six years. 19

Lower Urinary Tract Infections 20

Question l VQ, a 20 -year old woman with no previous history of UTI, complains of burning on urination, frequent urination of a small amount, and bladder pain. She has no fever or CVA tenderness. A clean-catch midstream urine sample shows Gram-negative rods on Gram stain. A culture and sensitivity test is ordered. Based on these findings, VQ is presumed to have a lower UTI. What should be the goals of therapy and treatment plan at this time? 21

Answer: l The goals of therapy in the treatment of acute cystitis are to eradicate the infection and prevent associated complications, while at the same time minimizing adverse effects and costs associated with drug therapy. Because resistance rates among various pathogens vary considerably among geographic areas, clinicians involved in the management of patients with UTI’s must be familiar with resistance rates within the specific area in which they practice. 22

Question: l What treatment duration options are available for VQ? 23

Answer: l The duration of therapy for UTI’s has been shortened considerably. The traditional seven to 14 day course of antibiotic therapy now is considered excessive for most patients with uncomplicated infections. A three day antibiotic treatment regimen is just as effective as a ten day regimen in eradicating urinary tract organisms, although this is somewhat antibiotic class-specific. Bactrim, Augmentin, and the fluoroquinolones are recommended as the preferred agents for three day treatment regimens. Nitrofurantoin, sulfoanamides other that Bactrim, and tetracyclines are more appropriately reserved for longer treatment failure following regimens of shorter duration. The choice of a specific agent should be based on geographic sensitivities as well as patient allergies and the relative cost of the agents. 24

Question: l LB is a 48 -year-old female, who presents with a community-acquired UTI. She has experienced a rash with Bactrim and developed acute shortness of breath while taking penicillin. What is the role of fluoroquinolones, such as cipro and levofloxicin, in her treatment? 25

Answer: l Although the fluoroquinolones are as effective as Bactrim in the treatment of uncomplicated UTI’s, they are not recommended as first-line therapy because they as very expensive and probably no more effective than conventional drugs. There also concerns regarding the overuse of fluoroquinolones and the promotion of drug resistance among community-acquired pathogens. A fluoroquinolone is appropriate for LB because it will be effective and because she has experienced previous adverse reactions to penicillins and sulfas. The duration of fluoroquinolone therapy in LB should be three days. 26

Question: l LB also is taking Maalox for a duodenal ulcer. What is the likelihood that this antacid will affect the action of the fluoroquinolones? 27

Answer: l It is imperative that the clinician question LB about other medications (both prescription and nonprescription). Products containing magnesium, calcium, zinc, aluminum and iron significantly decrease the absorption of fluoroquinolones, and this may result in theraputic failures. Although the administration of these medicines probably can be timed to avoid the interaction, this is inconvenient for the patient. Patients should simply avoid these products while taking fluoroquinolones. Ranitidine (Zantac) could be used those patients with GI ulcers. 28

Bacterial Vaginosis 29

Question: l SD is a 19 -year-old, sexually active woman with a one week history of a moderate vaginal discharge that has a “fishy” odor, most notable after coitus. She has no complaints of vaginal pruritus or burning. On examination, the discharge appears gray, homogeneous, and is notably malodorous. A diagnosis of bacterial vaginosis is made. How should SD be treated? 30

Answer: l Metronidazole 500 mg bid for 7 days is the most effective treatment. 85% of women remain well six weeks after completion of therapy. Clindamycin cream 2% at bedtime for seven days or metronidazole 0. 75% gel bid for 5 days are topical recommendations. Alternatively, the CDC recommends metronidazole 2 g orally in a single dose. 31

Question: l What patient instructions should be explained when dispensing clindamycin cream? 32

Answer: l Clindamycin cream is oil-based and may weaken latex condoms or diaphragms. 33

Treatment of Genital Herpes l BJ, a 28 -year-old, sexually active man, complains of painful penile lesions and tender inguinal adenopathy. The lesions are vesicular and limited to the scrotum and shaft of the penis. The onset of the lesions was preceded by a one week period of fever, malaise, headache, and itching. Viral cultures of the lesions were positive for herpes simplex virus. How should BJ’s lesions be treated? 34

Question: l What adverse effects secondary to acyclovir, famciclovir or valacyclovir should be anticipated? 35

Answer: l Renal: hematuria, increase in BUN and creatinine 36

Question: l What topical agents should be avoided in patients with genital herpes? 37

Answer: l Topical local anesthetics should be avoided because they counteract efforts to keep the lesions dry. Topical corticosteroids may predispose the patient to secondary bacterial infections. 38

Genital Warts 39

Question: l SL, a 22 -year-old woman, presents to the health clinic for her annual pelvic examination. One week later, her Pap smear is read as showing koilocytosis. A colposcopy is subsequently performed, revealing changes consistent with cervical flat warts due to the human papilloma virus (HPV). What topical agents are available to treat these lesions and how are they applied? 40

Answer: l l l Podophyllin 10 -25% solution is applied to visible warts. After application, it is washed off three to four hours later and then reapplied once or twice weekly until the warts have disappeared. Podofilox 0. 5% solution or gel (the active component of podophyllin) may be applied by the patient with a cotton swab to visible genital warts twice a day for three days, followed by four days of no therapy. A total of four cycles should not be exceeded. Imiquimod may be applied with a finger at bedtime three times weekly up to 16 weeks. It is usually left on for six to ten hours before it is washed off with soap and water. It may take as long as eight weeks before warts are cleared. Tricholoracetic acid is used topically in the treatment of genital warts, but its efficacy is unclear. 41

Question: l What side effects are seen with the topical treatment of HPV? 42

Answer: l l Podophyllin is potentially neurotoxic if asorbed in large amounts. Therefore, it should be applied in limited doses and should be avoided in pregnancy. The rate of recurrence is 50% Imiquimod causes mild to moderate local irritation in more than half of the patients who use it, especially when used daily instead of three times weekly. 43