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Bacterial pneumonia is a common cause of HIV-associated morbidity. The incidence of bacterial pneumonia among HIV-infected persons is greater than that in the noninfected population (454Hirschtick R, Glassroth J, Jordan MC, et al. Bacterial pneumonia in persons infected with the human immunodeficiency virus. N Engl J Med 1995;333:845-51.). In the precombination ART era, the Pulmonary Complications of HIV Infection Study reported that the incidence of bacterial pneumonia ranged was 3.9-7.3 episodes per 100 person-years (455Wallace JM, Hansen NI, Lavange L, et al. Respiratory disease trends in the Pulmonary Complications of HIV Infection Study cohort. Am J Respir Crit Care Med 1997;72-80.). In the current era, the incidence of bacterial pneumonia in HIV-infected persons has declined (4Jones JL, Hanson DL, Dworkin MS, et al. Surveillance for AIDS-defining opportunistic illnesses, 1992-1997. In: Surveillance Summaries, April 16, 1999. MMWR 1999;48:(No. SS-2)., 456Sullivan JH, Moore RD, Keruly JC, Chaisson RE. Effect of antiretroviral therapy on the incidence of bacterial pneumonial in patients with advanced HIV infection. Am J Respir Crit Care Med 2000;162:64-7., 457Serraino D, Puro V, Boumis E, et al. Epidemiological aspects of major opportunistic infections of the respiratory tract in persons with AIDS: Europe, 1993-2000. AIDS 2003;17:2109-16.).

Bacterial pneumonia might be the first manifestation of underlying HIV infection and can occur at any stage of HIV disease and at any CD4⁺ count. The high rates of bacterial pneumonia in HIV-infected persons probably result from multiple factors, including qualitative B-cell defects that impair ability to produce pathogen-specific antibody, impaired neutrophil function or numbers or both, and factors (e.g., injection drug use) that are associated with underlying HIV infection. Risk factors associated with an increased risk for bacterial pneumonia, include low CD4⁺ count, injection-drug use, and cigarette smoking (454Hirschtick R, Glassroth J, Jordan MC, et al. Bacterial pneumonia in persons infected with the human immunodeficiency virus. N Engl J Med 1995;333:845-51.).

Similar to persons without HIV infection, Streptococcus pneumoniae and Haemophilus species are the most frequently identified causes of community-acquired bacterial pneumonia in HIV-infected persons (458Polsky B, Gold JW, Whimbey E, et al. Bacterial pneumonia in patients with the acquired immunodeficiency syndrome. Ann Intern Med 1986;104:38-41., 459Burack JH, Hahn JA, Saint-Maurice D, Jacobson MA. Microbiology of community-acquired bacterial pneumonia in persons with and at risk for human immunodeficiency virus type 1 infection: implications for rational empiric antibiotic therapy. Arch Intern Med 1994;154:2589-96., 460Miller RF, Foley NM, Kessel D, Jeffrey AA. Community acquired lobar pneumonia in patients with HIV infection and AIDS. Thorax 1994;49:367-8., 461Mundy LM, Auwaerter PG, Oldach D, et al. Community-acquired pneumonia: impact of immune status. Am J Respir Crit Care Med 1995;152:1309-15., 462Afessa B, Green B. Bacterial pneumonia in hospitalized patients with HIV infection: the Pulmonary Complications, ICU Support, and Prognostic Factors of Hospitalized Patients with HIV (PIP) Study. Chest 2000; 117:1017-22., 463Park DR, Sherbin VL, Goodman MS, et al. The etiology of community-acquired pneumonia at an urban public hospital: influence of human immunodeficiency virus infection and initial severity of illness. J Infect Dis 2001;184:268-77., 464Rimland D, Navin TR, Lennox JL, et al. Prospective study of etiologic agents of community-acquired pneumonia in patients with HIV infection. AIDS 2002;16:85-95.). Similar to the noninfected population, drug-resistant Streptococcus pneumoniae is an increasing concern and is associated with increased mortality (465Turett GS, Blum S, Fazal BA, Justman JE, Telzak EE. Penicillin resistance and other predictors of mortality in pneumococcal bacteremia in a population with high human immunodeficiency virus seroprevalence. Clin Infect Dis 1999;29:321-7.).

Although atypical bacterial pathogens such as Legionella pneumophila, Mycoplasma pneumoniae, and Chlamydophila species have been reported as infrequent causes of community-acquired bacterial pneumonia in HIV-infected persons (461Mundy LM, Auwaerter PG, Oldach D, et al. Community-acquired pneumonia: impact of immune status. Am J Respir Crit Care Med 1995;152:1309-15., 466Tarp B, Jensen JS, Ostergaard L, Andersen PL. Search for agents causing atypical pneumonia in HIV-positive patients by inhibitor-controlled PCR assays. Eur Respir J 1999;13:175-9.), they are important considerations in decisions regarding antibiotic treatment.

In contrast to the noninfected population, Pseudomonas aeruginosa and Staphylococcus aureus are both reported as community-acquired pathogens with an increased frequency among persons with HIV infection (462Afessa B, Green B. Bacterial pneumonia in hospitalized patients with HIV infection: the Pulmonary Complications, ICU Support, and Prognostic Factors of Hospitalized Patients with HIV (PIP) Study. Chest 2000; 117:1017-22., 467Levine SJ, White DA, Fels AO. The incidence and significance of Staphylococcus aureus in respiratory cultures from patients infected with the human immunodeficiency virus. Am Rev Respir Dis 1990;141:89-93.).

Compared with persons without HIV infection, HIV-infected persons have an increased incidence of bacteremia accompanying pneumonia, especially if they are infected with S.pneumoniae. (468Redd SC, Rutherford GW, 3rd, Sande MA, et al. The role of human immunodeficiency virus infection in pneumococcal bacteremia in San Francisco residents. J Infect Dis 1990;162:1012-7., 469Falco V, Fernandez de Sevilla T, Alegre J, et al. Bacterial pneumonia in HIV-infected patients: a prospective study of 68 episodes. Eur Respir J 1994;7:235-9., 470Feldman C, Glatthaar M, Morar R, et al. Bacteremic pneumococcal pneumonia in HIV-seropositive and HIV-seronegative adults. Chest 1999;116:107-14.). In one study, the estimated rate of pneumococcal bacteremia (9.4 cases per 1,000 patient-years) in AIDS patients was approximately 100-fold greater than in HIV-uninfected historical controls (468Redd SC, Rutherford GW, 3rd, Sande MA, et al. The role of human immunodeficiency virus infection in pneumococcal bacteremia in San Francisco residents. J Infect Dis 1990;162:1012-7.).

Bacterial pneumonia is associated with an increased mortality among HIV-infected persons (462Afessa B, Green B. Bacterial pneumonia in hospitalized patients with HIV infection: the Pulmonary Complications, ICU Support, and Prognostic Factors of Hospitalized Patients with HIV (PIP) Study. Chest 2000; 117:1017-22., 471Osmond DH, Chin DP, Glassroth J, et al. Impact of bacterial pneumonia and Pneumocystis carinii pneumonia on human immunodeficiency virus disease progression. Clin Infect Dis 1999;29:536-43., 472Kohli R, Lo Y, Homel P, et al. Bacterial pneumonia, HIV therapy, and disease progression among HIV-infected women in the HIV epidemiologic research (HER) study. Clin Infect Dis 2006;43:90-8.). Among HIV-infected persons with community-acquired bacterial pneumonia, a prospective, multicenter study documented that a CD4⁺ count <100 cells/µL, radiographic progression of disease, and the presence of shock were independent predictors of increased mortality (473Cordero E, Pachon J, Rivero A, et al. Community-acquired bacterial pneumonia in human immunodeficiency virus-infected patients: validation of severity criteria. Am J Respir Crit Care Med 2000;162:2063-8.). In this study, multilobar infiltrates, cavitary infiltrates, and pleural effusion at baseline were all independent predictors of radiographic progression of HIV.

The clinical and radiographic presentation of bacterial pneumonia in HIV-infected persons is similar to that in persons without HIV infection. Persons with pneumonias caused by Streptococcus pneumoniae and Haemophilus species characteristically have an acute onset (3-5 days) of symptoms, including fevers, chills, rigors, chest pain, cough productive of purulent sputum, and dyspnea (92Selwyn PA, Pumerantz AS, Durante A, et al. Clinical predictors of Pneumocystis carinii pneumonia, bacterial pneumonia and tuberculosis in HIV-infected patients. AIDS 1998;12:885-93.). On examination of vital signs, patients are often febrile. The presence of tachycardia or hypotension is an indicator of the systemic inflammatory response syndrome (SIRS). Tachypnea and decreased arterial oxygen saturation indicate moderate-to-severe pneumonia and clinicians should strongly consider hospitalizing such patients.

Persons with bacterial pneumonia typically have evidence of focal consolidation and/or pleural effusion on lung examination, as contrasted to persons with PCP, in which the lung examination is often normal or, if abnormal, reveals inspiratory crackles.

The white blood cell (WBC) count is usually elevated in persons with bacterial pneumonia. In persons with advanced HIV disease, the elevation might be relative to the persons's baseline WBC. A left shift also might be present.

Persons with bacterial pneumonia characteristically exhibit unilateral, focal, segmental, or lobar consolidation on chest radiograph. However, the frequency of these typical radiographic findings might depend on the underlying bacterial pathogen. HIV-infected persons might present with multifocal or multilobar involvement and with parapneumonic effusions more frequently than persons without HIV infection (474Gil Suay V, Cordero PJ, Martinez E, et al. Parapneumonic effusions secondary to community-acquired bacterial pneumonia in human immunodeficiency virus-infected patients. Eur Respir J 1995;8:1934-9.).

Guidelines for the management of community-acquired pneumonia (CAP) in persons without HIV infection also apply to HIV-infected persons (475Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis 2007;44(Suppl 2):S27-72.). Persons with clinical symptoms and signs suggestive of CAP should have a chest radiograph. When available, previous radiographs should be reviewed to assess for the presence of new findings. The clinical diagnosis of bacterial pneumonia requires a demonstrable infiltrate.

Given the increased incidence of Mycobacterium tuberculosis in HIV-infected persons, the diagnosis of TB should always be suspected in HIV-infected persons who have pneumonia. Those persons with a clinical and radiographic evidence suggestive of TB should be managed as potential TB (e.g., respiratory isolation if hospitalized), and three sputum specimens should be obtained for AFB smear and culture. Dual therapy for both bacterial pneumonia and TB is appropriate for patients for whom both of these diagnoses are considerations and where diagnostic studies are undertaken.

Standard recommendations for routine testing for bacterial pneumonia remain controversial (475Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis 2007;44(Suppl 2):S27-72.). Usually, the differential diagnosis of pneumonia in HIV-infected persons is broad and a confirmed microbiologic diagnosis might allow clinicians to target the specific pathogen and to discontinue broad spectrum antibiotic therapy and/or empiric therapy that targets nonbacterial pathogens (e.g., empiric PCP therapy). The increased incidence of bacteremia in HIV-infected persons (especially at low CD4⁺ count) and the high specificity of blood cultures argue for their collection in HIV-infected persons. Although the low sensitivity of sputum and blood cultures and the infrequency that these results alter clinical management in HIV-uninfected patients with CAP argue against their routine collection, patients with HIV infection are at increased risk for infection with drug-resistant Streptococcus pneumococci (drug-resistant S. pneumoniae) and identification of this organism could lead to changes in management.

HIV-infected persons with suspected CAP should undergo investigation for specific pathogens that would significantly alter standard (empirical) management decisions when the presence of such pathogens is suspected on the basis of epidemiologic, clinical, or radiologic clues. Pseudomonas aeruginosa should be considered in HIV-infected persons with advanced HIV disease (i.e., CD4⁺ count ≤50 cells/µL); those with pre-existing lung disease (i.e., bronchiectasis); underlying neutropenia, corticosteroid therapy, or severe malnutrition; those who have been hospitalized within 90 days or reside in a health-care facility or nursing home; and those on chronic hemodialysis. Given the frequency of cavitary infiltrates in persons with P. aeruginosa, this radiographic finding should also prompt an investigation for this pathogen. Staphylococcus aureus should be considered in persons with recent viral (or influenza) infection; history of injection-drug use; or severe, bilateral, necrotizing pneumonia.

Routine diagnostic tests to identify an etiologic diagnosis are optional for persons with CAP who are well enough to be treated as outpatients, especially true if microbiologic studies cannot be performed promptly.

A pretreatment expectorated sputum specimen for Gram stain and culture and two blood cultures should be obtained from persons with CAP who are hospitalized, especially if intensive care is required. Gram stain and culture of expectorated sputum should be performed only if a good-quality specimen can be obtained and quality performance measures for collection, transport, and processing of samples can be met. Correlation of the sputum culture with the Gram stain can help in the interpretation of sputum culture data. For intubated patients, an endotracheal aspirate sample should be obtained. In addition to the above tests, urinary antigen tests for Legionella pneumophila and Streptococcus pneumoniae should be considered.

Diagnostic thoracentesis should be considered in any person with pleural effusion, especially if a concern exists for accompanying empyema, and a therapeutic thoracentesis should be performed to relieve respiratory distress secondary to a moderate- to large-sized effusion.

No effective means exist to reduce exposure to Streptococcus pneumoniae and Haemophilus influenzae, which are common in the community.

HIV-infected adults and adolescents who have a CD4⁺ count of >200 cells/µL should be administered a single dose of 23-valent polysaccharide pneumococcal vaccine (PPV) unless they have received this vaccine during the previous 5 years (AII) (157Dworkin MS, Hanson DL, Navin TR. Survival of patients with AIDS, after diagnosis of Pneumocystis carinii pneumonia, in the United States. J Infect Dis 2001;183:1409-12., 476Gebo KA, Moore RD, Keruly JC, Chaisson RE. Risk factors for pneumococcal disease in human immunodeficiency virus-infected patients. J Infect Dis 1996;173:857-62., 477Guerrero M, Kruger S, Saitoh A, et al. Pneumonia in HIV-infected patients: a case-control survey of factors involved in risk and prevention. AIDS 1999;13:1971-5., 479CDC. Recommended adult immunization schedule-United States, October 2007-September 2008. MMWR 2007; 56(41):2-4.). One randomized placebo-controlled trial of pneumococcal vaccine in Africa paradoxically determined that an increased risk for pneumonia was associated with vaccination (480French N, Nakiyingi J, Carpenter LM, et al. 23-valent pneumococcal polysaccharide vaccine in HIV-1-infected Ugandan adults: double-blind, randomised and placebo controlled trial. Lancet 2000;355:2106-11.). Follow-up of this cohort confirmed the increase in pneumonia in vaccinated subjects but also reported a decrease in all-cause mortality (481Watera C, Nakiyingi J, Miiro G, et al. 23-Valent pneumococcal polysaccharide vaccine in HIV-infected Ugandan adults: 6-year follow-up of a clinical trial cohort. AIDS 2004;18:1210-3.). In contrast, multiple observational studies of pneumococcal vaccine in the United States have reported benefits from vaccination (157Dworkin MS, Hanson DL, Navin TR. Survival of patients with AIDS, after diagnosis of Pneumocystis carinii pneumonia, in the United States. J Infect Dis 2001;183:1409-12., 476Gebo KA, Moore RD, Keruly JC, Chaisson RE. Risk factors for pneumococcal disease in human immunodeficiency virus-infected patients. J Infect Dis 1996;173:857-62., 477Guerrero M, Kruger S, Saitoh A, et al. Pneumonia in HIV-infected patients: a case-control survey of factors involved in risk and prevention. AIDS 1999;13:1971-5., 479CDC. Recommended adult immunization schedule-United States, October 2007-September 2008. MMWR 2007; 56(41):2-4., 482Hung CC, Chen MY, Hsieh SM, Hsiao CF, Sheng WH. Clinical experience of the 23-valent capsular polysaccharide pneumococcal vaccination in HIV-1-infected patients receiving highly active antiretroviral therapy: a prospective observational study. Vaccine 2004;22:2006-12.). Studies also have documented that vaccination is associated with a lower risk for pneumococcal bacteremia (482Hung CC, Chen MY, Hsieh SM, Hsiao CF, Sheng WH. Clinical experience of the 23-valent capsular polysaccharide pneumococcal vaccination in HIV-1-infected patients receiving highly active antiretroviral therapy: a prospective observational study. Vaccine 2004;22:2006-12., 483Grau I, Pallares R, Tubau F, Schulze MH, et al. Epidemiologic changes in bacteremic pneumococcal disease in patients with human immunodeficiency virus in the era of highly active antiretroviral therapy. Arch Intern Med 2005; 165:1533-40.). The majority of HIV specialists believe that the potential benefit of pneumococcal vaccination in the United States outweighs the risk.

HIV-infected adults and adolescents who have a CD4⁺ count of <200 cells/µL can be offered PPV (CIII). Clinical evidence has not confirmed efficacy in this group, but evidence documents the benefit for those who also start ART (482Hung CC, Chen MY, Hsieh SM, Hsiao CF, Sheng WH. Clinical experience of the 23-valent capsular polysaccharide pneumococcal vaccination in HIV-1-infected patients receiving highly active antiretroviral therapy: a prospective observational study. Vaccine 2004;22:2006-12.). Revaccination can be considered for persons who were initially vaccinated when their CD4⁺ counts were <200 cells/µL and whose CD4⁺ counts have increased to >200 cells/µL in response to ART (CIII).

The duration of the protective effect of primary pneumococcal vaccination is unknown; revaccination every 5 years may be considered (CIII) (479CDC. Recommended adult immunization schedule-United States, October 2007-September 2008. MMWR 2007; 56(41):2-4.). No evidence confirms clinical benefit from revaccination. Nevertheless, the recommendation to vaccinate is increasingly pertinent because of the increasing incidence of invasive infections with drug-resistant (including TMP-SMX-, macrolide-, and ß-lactam-resistant) strains of S. pneumoniae.

The incidence of H. influenzae type b (Hib) infection among HIV-infected adults is low. Therefore, Hib vaccine is not usually recommended for adult use (DIII).

Several factors are associated with a decreased risk for bacterial pneumonia, including the use of combination ART and TMP-SMX used for PCP prophylaxis (472Kohli R, Lo Y, Homel P, et al. Bacterial pneumonia, HIV therapy, and disease progression among HIV-infected women in the HIV epidemiologic research (HER) study. Clin Infect Dis 2006;43:90-8.). The use of antimicrobial prophylaxis to prevent bacterial pneumonia has been explored. In many studies, TMP-SMX, when administered daily for PCP prophylaxis, reduces the frequency of bacterial respiratory infections (430, 114Hardy WD, Feinberg J, Finkelstein DM, et al. A controlled trial of trimethoprim-sulfamethoxazole or aerosolized pentamidine for secondary prophylaxis of Pneumocystis carinii pneumonia in patients with the acquired immunodeficiency syndrome. N Engl J Med 1992;327:1842-8., 454Hirschtick R, Glassroth J, Jordan MC, et al. Bacterial pneumonia in persons infected with the human immunodeficiency virus. N Engl J Med 1995;333:845-51.). This should be considered in selecting an agent for PCP prophylaxis (AII). However, indiscriminate use of this drug (when not indicated for PCP prophylaxis or other specific reasons) might promote development of TMP-SMX-resistant organisms. Thus, TMP-SMX should not be prescribed solely to prevent bacterial respiratory infection (DIII). Similarly, clarithromycin administered daily or azithromycin administered weekly for MAC prophylaxis might be effective in preventing bacterial respiratory infections (421Havlir DV, Dube MP, Sattler FR, et al. Prophylaxis against disseminated Mycobacterium avium complex with weekly azithromycin, daily rifabutin, or both. N Engl J Med 1996;335:392-8., 484Oldfield EC, Fessel WJ, Dunne MW, et al. Once weekly azithromycin therapy for prevention of Mycobacterium avium complex infection in patients with AIDS: a randomized, double-blind, placebo-controlled multicenter trial. Clin Infect Dis 1998;26:611-9.). This should be considered in selecting an agent for prophylaxis against MAC (BII). However, these drugs should not be prescribed solely for preventing bacterial respiratory infection (DIII).

An absolute neutrophil count that is depressed because of HIV disease or drug therapy is associated with an increased risk for bacterial infections, including pneumonia. To reduce the risk for such bacterial infections, health-care providers might consider taking steps to reverse neutropenia, either by stopping myelosuppressive drugs (CII) or by administering granulocyte-colony stimulating factor (G-CSF) (CII).

Modifiable factors associated with an increased risk for bacterial pneumonia include smoking cigarettes and other drugs, injection-drug use (IDU), and alcohol use (138Crothers K, Beard CB, Turner J, et al. Severity and outcome of HIV-associated Pneumocystis pneumonia containing Pneumocystis jirovecii dihydropteroate synthase gene mutations. AIDS 2005;19:801-5., 454Hirschtick R, Glassroth J, Jordan MC, et al. Bacterial pneumonia in persons infected with the human immunodeficiency virus. N Engl J Med 1995;333:845-51., 485Navin TR, Rimland D, Lennox JL, et al. Risk factors for community-acquired pneumonia among persons infected with human immunodeficiency virus. J Infect Dis 2000; 181:158-64., 486Justice AC, Lasky E, McGinnis KA, et al. Medical disease and alcohol use among veterans with human immunodeficiency infection: a comparison of disease measurement strategies. Med Care 2006;44(Suppl 2):S52-60.). Clinicians should encourage cessation of these behaviors, although no data exist to indicate that cessation decreases risk (CIII).

Inactivated influenza vaccine should be administered annually to all HIV-infected persons during influenza season (AIII). This recommendation is pertinent to prevention of bacterial pneumonia, which might occur as a complication of influenza illness. Live attenuated influenza vaccine is contraindicated for HIV-infected persons (EIII).

The principles of the treatment of community-acquired bacterial pneumonia are the same for HIV-infected persons as for HIV-uninfected persons (475Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis 2007;44(Suppl 2):S27-72.). Usually, collection of specimens for microbiologic studies should be performed before the initiation of antibiotic therapy. However, antibiotic therapy should be administered promptly, without waiting for the results of diagnostic testing.

An assessment of disease severity and arterial oxygenation should be performed in all persons with pneumonia. Noninvasive measurement of arterial oxygen saturation via pulse oximetry is an appropriate screening test. However, ABG analysis is indicated for persons with evidence of hypoxemia suggested by noninvasive assessment and for persons with tachypnea and/or respiratory distress. Criteria that were developed to assess CAP disease severity in HIV-uninfected persons have been found to be valid for HIV-infected persons (473Cordero E, Pachon J, Rivero A, et al. Community-acquired bacterial pneumonia in human immunodeficiency virus-infected patients: validation of severity criteria. Am J Respir Crit Care Med 2000;162:2063-8.). Unlike recommendations for CAP therapy in non-HIV patients, no HIV-infected patient should receive macrolide monotherapy because of the increased risk for drug-resistant Streptococcus pneumoniae in the HIV-infected patient.

Outpatient Treatment

HIV-infected persons who are being treated as outpatients should receive an oral beta-lactam plus an oral macrolide (AII). Preferred beta-lactams are high-dose amoxicillin and amoxicillin-clavulanate; cefpodoxime and cefuroxime are alternatives. Preferred macrolides are azithromycin and clarithromycin. Oral doxycycline is an alternative to the macrolide (CIII). For persons who are allergic to penicillin or who have received a beta-lactam within the previous 3 months, an oral respiratory fluoroquinolone (moxifloxacin, levofloxacin [750 mg/day], or gemifloxacin) should be used (AII). Respiratory fluoroquinolones are active against Mycobacterium tuberculosis. Thus, persons with TB who are treated with fluoroquinolone monotherapy might respond initially, but this response might be misleading, might delay the diagnosis of TB and the initiation of appropriate multi-drug therapy, and might increase the risk for transmission of TB. Thus, fluoroquinolones should be used with caution in patients in whom TB is suspected but who are not being treated with concurrent standard four-drug TB therapy. Because HIV-infected persons have an increased incidence of TB and the presentation of TB can be varied in HIV-infected persons, fluoroquinolones should be used only when the presentation strongly suggests bacterial pneumonia. Increasing pneumococcal resistance rates have suggested that empirical therapy with a macrolide alone cannot be routinely recommended (DIII). Patients who are receiving a macrolide for MAC prophylaxis should never receive macrolide monotherapy for empiric treatment of bacterial pneumonia.

Non-ICU Inpatient Treatment

HIV-infected persons who are being treated as inpatients should receive an IV beta-lactam plus a macrolide (AII). Preferred beta-lactams are ceftriaxone, cefotaxime, or ampicillin-sulbactam. Doxycycline is an alternative to the macrolide (CIII). For persons who are allergic to penicillin or who have received a beta-lactam within the previous 3 months, an IV respiratory fluoroquinolone (moxifloxacin or levofloxacin [750 mg/day]) should be used (AII). Because of the activity of fluoroquinolones against Mycobacterium tuberculosis and the dangers of monotherapy in persons with TB, fluoroquinolones should be used with caution in patients in whom TB is suspected but is not being treated with concurrent standard four-drug TB therapy. Increasing pneumococcal resistance rates have suggested that empirical therapy with a macrolide alone cannot be recommended routinely (DIII). Patients who are receiving a macrolide for MAC prophylaxis should never receive macrolide monotherapy for empiric treatment of bacterial pneumonia.

ICU Treatment

Persons with severe pneumonia who require intensive care should be treated with an IV beta-lactam plus either IV azithromycin (AII) or an IV respiratory fluoroquinolone (moxifloxacin or levofloxacin [750 mg/day]) (AII). Preferred beta-lactams are ceftriaxone, cefotaxime, or ampicillin-sulbactam. For persons who are allergic to penicillin or who have received a beta-lactam within the previous 3 months, aztreonam plus an IV respiratory fluoroquinolone (moxifloxacin or levofloxacin [750 mg/day]) should be used (BIII). Infections with the overwhelming majority of CAP pathogens will be treated adequately by use of the recommended empirical regimens. The increased incidence of P. aeruginosa and S. aureus as a cause of CAP is the exception. These pathogens occur in specific epidemiologic patterns with distinct clinical presentations, for which empirical antibiotic coverage might be warranted. Diagnostic tests (sputum Gram stain and culture) are likely to be of high yield for these pathogens, allowing early discontinuation of empirical treatment if results are negative.

Empiric Pseudomonas aeruginosa Treatment

If risk factors for Pseudomonas infection are present, an antipneumococcal, antipseudomonal beta-lactam plus either ciprofloxacin or levofloxacin (750 mg dose) should be used (BIII). Preferred beta-lactams are piperacillin-tazobactam, cefepime, imipenem, or meropenem. An antipneumococcal, antipseudomonal beta-lactam plus an aminoglycoside and azithromycin (BIII) or an antipneumococcal, antipseudomonal beta-lactam plus an aminoglycoside and an antipneumococcal fluoroquinolone (BIII) are alternatives. For persons who are allergic to penicillin or who have received a beta-lactam within the previous 3 months, aztreonam can be used in place of the beta-lactam (BIII).

Empiric Staphylococcus aureus Treatment

If risk factors for Staphylococcus aureus infection, including community-acquired methicillin-resistant S. aureus, are present, vancomycin (possibly in combination with clindamycin) or linezolid alone should be added to the antibiotic regimen (BIII).

Pathogen-Directed Therapy

When the etiology of pneumonia has been identified on the basis of reliable microbiological methods, antimicrobial therapy should be directed at that pathogen (BIII).

Switch from Intravenous to Oral Therapy

For patients with CAP who begin IV antibiotic therapy, switching to oral therapy should be considered when they are improving clinically, are able to swallow and tolerate oral medications, and have intact gastrointestinal function. Suggested criteria for clinical stability include oral temperature <37.8 °C, heart rate <100 beats/minute, respiratory rate <24 breaths/minute, systolic blood pressure ≥90 mm Hg, and room air oxygen saturation >90% or partial pressure of oxygen in arterial blood (PaO2) >60 mm Hg (475Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis 2007;44(Suppl 2):S27-72.).

The clinical response to appropriate antimicrobial therapy is similar in HIV-infected and non-HIV-infected persons (487Christensen D, Feldman C, Rossi P, et al. HIV infection does not influence clinical outcomes in hospitalized patients with bacterial community-acquired pneumonia: results from the CAPO international cohort study. Clin Infect Dis 2005;41:554-6.). A clinical response (i.e., a reduction in fever and improvement in respiratory symptoms, physical findings, and laboratory studies) is typically observed within 48-72 hours after the initiation of appropriate antimicrobial therapy. Usually, radiographic improvement might lag behind clinical improvement. If a patient has progressive pneumonia in spite of therapy, leading to severe CAP, adjunctive therapy with corticosteroids might be appropriate to ameliorate the inflammatory reaction to killing bacteria in the lung parenchyma (CIII).

IRIS has not been described in association with bacterial respiratory disease and treatment with ART in HIV-infected persons.

Persons who fail to respond to appropriate antimicrobial therapy should undergo further evaluation to search for other infectious and noninfectious causes of pulmonary dysfunction. The possibility of TB should always be considered in HIV-infected persons with pulmonary disease.

HIV-infected persons should receive pneumococcal and influenza vaccine as recommended. Clinicians can administer antibiotic chemoprophylaxis to HIV-infected patients who have frequent recurrences of serious bacterial respiratory infections (CIII). TMP-SMX, administered for PCP prophylaxis, and clarithromycin or azithromycin, administered for MAC prophylaxis, are appropriate for drug-sensitive organisms. However, health-care providers should be cautious when using antibiotics solely for preventing the recurrence of serious bacterial respiratory infections because of the potential development of drug-resistant microorganisms and drug toxicity.

The diagnosis of bacterial respiratory-tract infections among pregnant women is the same as for nonpregnant women, with appropriate shielding of the abdomen during radiographic procedures. Bacterial respiratory-tract infections should be managed as in nonpregnant women, with certain exceptions. Because of an increased risk for birth defects evident in some animal studies, clarithromycin is not recommended as the first-line agent among macrolides. Two studies, each involving at least 100 women with first-trimester exposure to clarithromycin, did not document a clear increase in or specific pattern of birth defects, although an increased risk for spontaneous abortion was noted in one study (452Einarson A, Phillips E, Mawji F, et al. A prospective controlled multicentre study of clarithromycin in pregnancy. Am J Perinatol 1998;15:523-5., 453Drinkard CR, Shatin D, Clouse J. Postmarketing surveillance of medications and pregnancy outcomes: clarithromycin and birth malformations. Pharmacoepidemiol Drug Saf 2000;9:549-56.). Azithromycin did not produce birth defects in animal studies, but experience with human use in the first trimester is limited. Azithromycin is recommended when a macrolide is indicated in pregnancy (BIII). Arthropathy has been noted in immature animals exposed in utero to quinolones. However, approximately 400 cases of quinolone use in human pregnancies have been reported to various pregnancy registries, and use has not been associated with human arthropathy or birth defects after in utero exposure. Thus, quinolones can be used in pregnancy for serious respiratory infections when indicated (CIII) (395Nahum GG, Uhl K, Kennedy DL. Antibiotic use in pregnancy and lactation: what is and is not known about teratogenic and toxic risks. Obstet Gynecol 2006;107:1120-38.). Doxycycline is not recommended for use during pregnancy because of increased hepatotoxicity and staining of fetal teeth and bones. Beta-lactam antibiotics have not been associated with teratogenicity or increased toxicity in pregnancy. Aminoglycosides may be used as needed. Although a theoretical risk for fetal renal or eighth nerve damage can occur with exposure during pregnancy, this finding has not been documented in humans except with streptomycin (10% risk) and kanamycin (2% risk). Experience with linezolid in human pregnancy has been limited, but it was not teratogenic in mice, rats, and rabbits.

Rates for preterm labor and preterm delivery are increased with pneumonia during pregnancy. Pregnant women with pneumonia after 20 weeks of gestation should be monitored for evidence of contractions (BII).

Pneumococcal vaccine can be administered during pregnancy (AIII). Although its safety during the first trimester of pregnancy has not been evaluated, no adverse consequences have been reported among newborns whose mothers were inadvertently vaccinated during pregnancy. Inactivated influenza vaccine also can be administered during pregnancy, and influenza vaccine is recommended for all pregnant women who will be pregnant during influenza season (AIII). Live attenuated influenza vaccine should not be used during pregnancy (EIII). Because administration of vaccines might be associated with a transient rise in plasma HIV RNA levels, vaccination of pregnant women is recommended after ART has been initiated to minimize increases in plasma HIV RNA levels that might increase the risk for perinatal HIV transmission.