Preventative antibiotic therapy in chest infections

Presented by :Mina Assaad Metry

Under the supervision of :Prof. Dr. Seham Hafez

I. Chronic lung infections:1- BronchiectasisBronchiectasis is an uncommon disease that

results in the abnormal and permanent distortion of one or more of the conducting bronchi or airways, most often secondary to an infectious process.

First described by Laennec in 1819, later detailed by Sir William Osler in the late 1800s

Presentation:(1) a focal process involving a lobe, segment, or

subsegment of the lung or(2) a diffuse process involving both lungs.

PathophysiologyBronchiectasis is an abnormal dilation of the

proximal and medium-sized bronchi (>2 mm in diameter) caused by weakening or destruction of the muscular and elastic components of the bronchial walls.

may be:-Congenital:Deficiency of immunoglobulins or deficiency in

mucocilliary escalator (immotile syndrome)-Acquired:Cystic bronchiectasisManifestations of bronchiectasisare cough and daily mucopurulent sputum production,

often lasting months to years. Blood-streaked sputum or hemoptysis may result from airway damage associated with acute infection.

A rare variant known as dry bronchiectasis manifests by episodic hemoptysis with little-to-no sputum production. Dry bronchiectasis is usually a sequela of tuberculosis and is found in the upper lobes.

CausesPrimary infections Bronchial obstruction Aspiration   Cystic fibrosis Young syndrome44 Primary ciliary dyskinesia Allergic bronchopulmonary aspergillosis48 Immunodeficiency states Congenital anatomic defects and connective-tissue disorders Alpha1-antitrypsin (AAT) deficiencyAutoimmune diseases and idiopathic inflammatory disorders Traction bronchiectasis: Traction bronchiectasis is distortion of the

airways secondary to mechanical traction on the bronchi from fibrosis of the surrounding lung parenchyma. Although the airways may become dilated in this situation, the other manifestations of bronchiectasis are lacking.

Toxic gas exposure: Exposure to toxic gas may often cause irreversible damage to the bronchial airways and cystic bronchiectasis. Commonly suspected agents include chlorine gas and ammonia.

Treatment General therapy

Patients should stop smoking. Patients should avoid second-hand smoke. Patients should have adequate nutritional intake with

supplementation, if necessary. Immunizations for influenza and pneumococcal pneumonia are

recommended.78,79 Immunizations for measles, rubeola, and pertussis should be

confirmed. Oxygen therapy is reserved for patients who are hypoxemic with

severe disease and end-stage complications, such as cor pulmonale.

Patients with CF should be cared for at specialized CF treatment centers that address all aspects of the disease, including nutritional and psychologic aspects.

Antibiotic Oral, parenteral, and aerosolized antibiotics are used,

depending on the clinical situation. In acute exacerbation, broad-spectrum antibacterial

agents are generally preferred. However, if time and the clinical situation allows, then sampling respiratory secretions during an acute exacerbation may allow treatment with antibiotics based on specific species identification.

for the outpatient who is mild to moderately ill include amoxicillin, tetracycline, trimethoprim-sulfamethoxazole, a newer macrolide (eg, azithromycin80 or clarithromycin81,82 ), a second-generation cephalosporin, or one of the fluoroquinolones. In general, the duration is 7-10 days.

For patients with moderate-to-severe symptoms, parenteral antibiotics, such as an aminoglycoside (gentamicin, tobramycin) and an antipseudomonal synthetic penicillin, a third-generation cephalosporin, or a fluoroquinolone, may be indicated. Patients with bronchiectasis from CF are often infected with mucoid Pseudomonas species, and, as such, tobramycin is often the drug of choice for acute exacerbation.

Additionally, some patients with chronic bronchial infections may need regular antibiotic treatment to control the infectious process. Some clinicians prefer to prescribe antibiotics on a regular basis or for a set number of weeks each month. The oral antibiotics of choice are the same as those mentioned previously. Potential regimens include daily antibiotics for 7-14 days of each month, alternating antibiotics for 7-10 days with antibiotic-free periods of 7-10 days, or a long-term daily dose of antibiotics. For patients with severe CF and bronchiectasis, intermittent courses of intravenous antibiotics are sometimes used.

Clarithromycin AzithromycinTrimethoprim

and sulfamethoxazol

eDoxycycline

Adult500 mg PO bid for 7-14 d

AdultDay 1: 500 mg PODays 2-5: 250 mg/d PO

Adult2 tab PO q12h for 14 d; if used monthly, alternatively may be administered as 10-d course

Adult100 mg PO bid for 10 days

Pediatric

Day 1: 10 mg/kg PO once; not to exceed 500 mg/dDays 2-5: 5 mg/kg/d PO; not to exceed 250 mg/d

Pediatric<2 months: Not recommended>2 months: 8 mg/kg TMP and 40 mg/kg SMZ PO per 24 h, administered in 2 divided doses q12h for 10 d

Pediatric<8 years: Not recommended>8 years: 2-5 mg/kg/d PO qd or divided bid; not to exceed 200 mg/d

Levofloxacin Gentamicin Tobramycin for inhalation

Amikacin

Adult500 mg PO/IV qd

Adult3 mg/kg/d IV divided tid in normal renal function; once-a-day dosing also effective; follow each regimen by at least a trough level drawn on the third or fourth dose (0.5 h before dosing); may draw a peak level 0.5 h after 30-min infusion

Adult300-mg dose administered via a nebulizer; recommended treatment regimen is repeated cycles of 28 d of medication q12h, followed by 28 d off

Adult10-15 mg/kg/d IV/IM divided bid/tid; not to exceed 1.5 g/d regardless of higher BW

Pediatric

<18 years: Not recommended>18 years: Administer as in adults

Pediatric6-7.5 mg/kg/d IV divided q8h

Pediatric

<6 years: Not recommended>6 years: Administer as in adults

PediatricNeonates: Dose variable to postconceptional and postnatal ageChildren: 15-22.5 mg/kg/d IV/IM divided q8h

2- Cystic fibrosisCystic fibrosis (CF) is a severe, complex,

hereditary disease that affects 1 of every 3,200 live births, or approximately 30,000 children and adults in the United States. One in 31 Americans carry the autosomal recessive gene for CF, which arises from a mutation in coding for the cystic fibrosis transmembrane regulator protein (CFTR). This genetic mutational error results in the complex, multisystem disease of CF, which is characterized by malabsorption and a state of chronic lung inflammation and infection.

Antibiotic Prophylaxis

Some clinicians prescribe prophylactic antibiotics in an effort to prevent S. aureus infections in young children and subsequent pseudomonas infections. In one randomized study, cephalexin significantly decreased colonization with S. aureus, but it also increased P. aeruginosa infections. Thus, routine antistaphylococcal prophylaxis is not recommended for young children with CF and would not be recommended for L.T.

Drug Daily Dosage (mg/kg) Frequency

Amikacin 30 Divided Q 8, 12,24

Ceftazidime 150–225 DividedQ 8 hr

Cefuroxime 150–225 DividedQ 8 hr

3- Tuberculosis Chemoprophylaxisin high-risk groups including human

immunodeficiency virus-infected patients, the elderly, the foreign born, and the homeless.

Chemoprophylaxis with 300 mg of isoniazid- O mg per kg for children-given daily for 6 to 12 months has been used to decrease the risk of active TB developing. 13 The efficacy of chemoprophylaxis ranges from 65% to 98%, depending on the length of treatment and level of compliance.

4- Kartagener SyndromeSiewert first described the combination of situs

inversus, chronic sinusitis, and bronchiectasis in 1904. However, Manes Kartagener1 first recognized this clinical triad as a distinct congenital syndrome in 1933. Because Kartagener described this syndrome in detail, it bears his name. Kartagener syndrome (KS) is inherited via an autosomal recessive pattern. Symptoms result from defective cilia motility.

Antibiotics, intravenous or oral and continuous or intermittent, are used to treat upper and lower airway infections. Although prophylactic antibiotics should be used with great caution in this era of emerging antibiotic resistance, children with primary ciliary dyskinesia are especially good candidates for long-term low-dose preventative antibiotics.

II. Acute lung infections:1- Acute bronchitisProphylactic antibiotic therapy may decrease the number of

acute exacerbations of bronchitis in patients with frequent episodes. In patients with infrequent exacerbations, prophylaxis is not beneficial and should be discouraged.

Antimicrobial prophylaxis should be considered in patients with frequent, severe exacerbations but used only during critical periods when patients are most susceptible. For example, daily doses of antibiotics 4 days a week during the winter months or a 7-day course of antibiotics at the first sign of a “chest cold” have been suggested.

amoxicillin, doxycycline, or TMP-SMX are preferred. Antipneumococcal fluoroquinolones should be avoided because of a lack of additional benefit, increased cost, and the concerns regarding selection for bacterial resistance.

2- bronchiolitisRibavirin should not be used routinely in children with

bronchiolitis (recommendation: evidence level B).Antibacterial medications should be used only in

children with bronchiolitis who have specific indications of the coexistence of a bacterial infection. When present, bacterial infection should be treated in the same manner as in the absence of bronchiolitis (recommendation: evidence level B).

When given, prophylaxis with palivizumab should be given in 5 monthly doses, usually beginning in November or December, at a dose of 15 mg/kg per dose administered intramuscularly (recommendation: evidence level C).

3- prophylaxis of influenzaOseltamivir and zanamivir are recommended, within their

marketing authorisations, for the post-exposure prophylaxis of influenza if all of the following circumstances apply.

National surveillance schemes have indicated that influenza virus is circulating.

The person is in an at-risk group (as defined below). The person has been exposed (see below) to an influenza-

like illness and is able to begin prophylaxis within the timescale specified in the marketing authorisations of the individual drugs (within 36 hours of contact with an index case for zanamivir and within 48 hours of contact with an index case for oseltamivir).

The person has not been effectively protected by vaccination

Risk patient includes people with:1. Chronic respiratory disease2. Chronic heart disease 3. Chronic renal disease 4. Chronic liver disease 5. Chronic neurological disease 6. Immunosuppression 7. Diabetes mellitus8. People who are aged 65 years or olderPeople who are not effectively protected by vaccination include:1. Those who have not been vaccinated since the previous

influenza season2. Those for whom vaccination is contraindicated, or in whom it

has yet to take effect 3. Those who have been vaccinated with a vaccine that is not

well matched (according to information from the Health Protection Agency) to the circulating strain of influenza virus

4- Pertusis Use of a Prophylactic Antibiotic Regimen for Contacts of

Persons with Pertussis Administer a macrolide to any person who has had close

contact with persons with pertussis and who does not have hypersensitivity or intolerance to macrolides (IB) Except in infants aged <2 weeks, use erythromycin(i.e., erythromycin estolate, 500 mg four times daily or

erythromycin delayed-release tablets, 333 mg three times daily for adults, and 40 to 50 mg/kg day for children) for 14 days (IB)

For patients who are intolerant to erythromycin or for infants aged <2 weeks, use any of the following regimens: azithromycin for 5 to 7 days (at 10–12 mg/kg/day) or for 5 days (at 10 mg/kg on day one followed by 4 days at 5 mg/kg/day) for infants and young children (Halperin, 2003); or clarithromycin for 10 to 14 days (at 500 mg twice a day for adults or 15–20 mg/kg/day in two divided doses for children) II

5- Treatment of Anthrax: ProphylaxisInhaled spores can remain dormant in the

lungs or lymphatic system for weeks to months before germination. After germination in alveolar macrophages, vegetative organisms can replicate and cause symptomatic disease. Reported incubation periods have ranged from 1 to 43 days after initial exposure but can be affected by the dose of B. anthracis inhaled and the use of antibiotics. Delayed disease onset is not known to occur with cutaneous or gastrointestinal exposures.

Two methods exist to protect against B. anthracis after the spores have reached the vegetative state.

1. The first is to have adequate levels of antibiotics in the bloodstream to kill vegetative bacteria.

2. The second is to have adequate anti-B. anthracis antibodies in the bloodstream when vegetative bacteria appear.

The 2002 Institute of Medicine report on anthrax vaccine safety and efficacy also concluded that on the basis of limited animal studies, anthrax vaccine administered in combination with antibiotics after exposure to B. anthracis spores might help prevent development of inhalational anthrax.

Ciprofloxacin, doxycycline, and penicillin G procaine have been approved by the Food and Drug Administration (FDA) for prophylaxis of inhalational Bacillus anthracis infection,

The optimal duration of prophylaxis is uncertain; however, 60 days was recommended, primarily on the basis of animal studies of anthrax deaths and spore clearance after exposure. The possible need for longer prophylaxis and vaccine was discussed

6- Pulmonary surgeryProphylactic systemic antibiotics significantly

reduced the number of pneumonectomy space and chest infections;

application of penicillin + streptomycin powder to the bronchial stump had no effect .

Systemic antibiotics given preoperatively reduced the incidence of bronchopleural fistula . The type of bacteria present in the preoperative sputum or bronchial lumen at operation was no help in predicting the effect therapy of postoperative infection.

Thank

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