skip navigation

Skip Nav

Clinical Guidelines Portal

Clinical Guidelines Portal

Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents

Bacterial Enteric Infections

(Last updated: May 7, 2013; last reviewed: May 7, 2013)


Rates of Gram-negative bacterial enteric infections are at least 10-fold higher among HIV-infected adults than in the general population but decline when patients are on antiretroviral therapy (ART).1-7 The risk of bacterial diarrhea varies according to CD4 T-lymphocyte (CD4) count and is greatest in individuals with clinical AIDS and/or <200 CD4 cells/mm3.5 The most common routinely cultured enteric bacteria among HIV-infected adults in the United States are Salmonella (particularly Salmonella enterica serotypes Typhimurium and Enteritidis), Shigella, and Campylobacter. Diarrheagenic Escherichia coli, particularly enteroaggregative E. coli, may contribute to the burden of diarrheal disease8 but their role is poorly understood because diagnosis requires specialized laboratory capacity. Clostridium difficile-associated infection (CDI) is common in HIV-infected patients, although it is unclear whether immunosuppression is associated with a higher risk of illness than traditional risk factors such as exposure to a healthcare facility or to antibiotics. Increased recognition of community-associated CDI without prior antibiotic or inpatient healthcare facility exposures in HIV-uninfected individuals suggests that the healthcare provider should consider CDI in the evaluation of outpatient diarrheal illnesses. Data on Helicobacter pylori infection in HIV infection are limited and do not suggest excess risk in HIV-infected individuals. Other enteric infections that may cause diarrhea, such as Mycobacterium avium complex and cytomegalovirus are discussed elsewhere in these guidelines.

As with bacterial enteric infections in HIV-uninfected persons, the probable source for most enteric infections in HIV-infected patients is ingestion of contaminated food or water.3 Sexual activity with the potential for direct or indirect fecal-oral exposure also increases risk of infections, especially with Shigella9 and Campylobacter10 (see Appendix for further details.). HIV-associated alterations in mucosal immunity or intestinal integrity and treatment with acid-suppressive agents may facilitate acquisition of enteric bacterial infections.

Clinical Manifestations

The three major clinical syndromes of infection with Gram-negative enteric bacteria among HIV-infected patients are:
  • Self-limited gastroenteritis;
  • More severe and prolonged diarrheal disease, potentially associated with fever, bloody diarrhea, and weight loss; and
  • Bacteremia associated with extra-intestinal involvement, with or without concurrent or preceding gastrointestinal illness.11-14
Severe community-associated diarrhea is often defined as ≥6 loose stools (loose stool is defined as defecated material that takes the shape of a container) per day with or without other signs of disease such as fecal blood, orthostatic hypotension, or fever. In HIV-infected patients, the risk of more profound illness increases with the degree of immunosuppression.1,3,4,15 Relapses in infection with Salmonella and other Gram-negative bacterial enteric pathogens after appropriate treatment have been well documented in HIV-infected patients.16-18


Assessment of patients with diarrhea should include a complete exposure history (see below); medication review, because diarrhea is a common side effect of some ART and antibiotics; quantification of the diarrheal illness by stool frequency, volume, duration, and presence of blood; and associated signs and symptoms, such as presence and duration of fever. Physical examination should include measurement of temperature and assessment of volume and nutritional status. 

The diagnosis of Gram-negative bacterial enteric infection is established through cultures of stool and blood. Because incidence of bacteremia associated with Salmonella gastroenteritis is high in HIV-infected individuals, particularly those with advanced disease, blood cultures should be obtained from any patient with diarrhea and fever. For shigellosis, blood cultures may be helpful but are less likely to be positive than in salmonellosis. 

Other infections for which HIV-infected patients are at risk, albeit at a lower rate, are non-jejuni non-coli Campylobacter species, such as Campylobacter fetus, Campylobacter upsaliensis, and Campylobacter lari, and the enterohepatic Helicobacter species (Helicobacter cineadi and Helicobacter fennelliae), which were originally described as Campylobacter species. Blood culture systems typically will grow these bacteria, but they are unlikely to be identified on routine stool cultures performed by most laboratories because special stool culture conditions are required for growth of these fastidious organisms. 

A stool sample for C. difficile toxin or polymerase chain reaction assay should be routinely performed for patients who have recently or are currently receiving antibiotics (including antimicrobial prophylaxis) or cancer chemotherapy, those who have been hospitalized in the past 4 to 6 weeks (or are currently hospitalized), those who reside in a long-term care facility, those with CD4 counts <200 cells/mm3, those taking acid-suppressive medications, and those with moderate-to-severe community-acquired diarrhea.19 The most commonly used toxin tests are enzyme immunoassays that suffer from low sensitivity. Polymerase chain reaction assays or glutamate dehydrogenase antigen enzyme immoassays (that must be combined with a second confirmatory test) have a high negative predictive value but may more likely detect asymptomatic colonization. Regardless of the test used, the diagnosis of CDI can only be made through careful selection of the correct population to test and a correlation of clinical and laboratory findings. 

Endoscopy generally should be reserved for patients in whom stool culture, microscopy, C. difficile toxin assay, and blood culture fail to reveal an etiology or in whom treatment for an established diagnosis fails. Endoscopy with biopsy may be required for diagnosing etiologies other than bacterial enteric infections, including cryptosporidiosis, microsporidiosis, cytomegalovirus or Mycobacterium avium complex gastroenteritis, and noninfectious causes of GI symptoms.

Clinicians should remain alert to the possibility of sexually transmitted disease. Some sexually transmitted rectal infections (such as proctitis due to lymphogranuloma venereum or Neisseria gonorrhoeae) can produce symptoms similar to those seen with colitis due to Salmonella, Shigella, and Campylobacter spp. In patients with symptoms of proctitis or colitis, if stool cultures fail to yield enteric bacterial pathogens, diagnostic evaluation for sexually transmitted diseases with anoscopy, culture, and biopsy should be considered.

Preventing Exposure 

Multiple epidemiologic exposures can place patients at risk of enteric illnesses. The most common are ingestion of contaminated food or water and fecal-oral exposures (detailed prevention recommendations related to food and water exposures, pet exposures, and travel-related exposures can be found in the Appendix). Providing advice and education about such exposures is the responsibility of the healthcare provider. A patient’s clinical condition and CD4 count can help the provider determine what prevention recommendations are most appropriate. Patients with CD4 counts <200 cells/mm3 or a history of AIDS-defining illness20 are at the greatest risk of enteric illnesses;5 however, excess risk of undetermined magnitude or duration may persist in those with lesser degrees of immune impairment, including individuals treated with ART. 

Patients should be advised to regularly wash their hands with soap and water or alcohol-based cleansers to reduce the risk of enteric infection (AIII). With regard to preventing enteric infection, soap and water are preferred over alcohol-based cleansers, which do not kill C. difficile spores and are only partially active against norovirus and Cryptosporidium (AIII). HIV-infected patients should be advised to wash their hands after potential contact with human feces, such as through defecation, cleaning feces from infants, or contact with a person who has diarrhea; after handling pets or other animals; after gardening or other contact with soil; before preparing food and eating; and before and after sex (AIII). HIV-infected patients should avoid unprotected sex practices, such as anal sex and oral-anal contact that could result in oral exposure to feces and, in addition to handwashing, they should be advised to use barriers such as dental dams during sex to reduce exposures when possible (AIII).

Preventing Disease

Antimicrobial prophylaxis to prevent bacterial enteric illness usually is not recommended, including for travelers (AIII). Prophylactic antimicrobial treatment can elicit adverse reactions, promote the emergence of resistant organisms, and increase risk of CDI. In rare cases, however, antimicrobial prophylaxis with fluoroquinolones or rifaximin can be considered, such as for immunosuppressed travelers, depending on their level of immunosuppression, the region of travel, and the trip’s duration (CIII). For pregnant women and patients already taking trimethoprim-sulfamethoxazole (TMP-SMX) (such as for Pneumocystis jirovecii pneumonia prophylaxis), TMP-SMX may offer limited protection against travelers’ diarrhea as an alternative to fluoroquinolones or rifaximin (BIII). Risk of toxicity should be considered before prophylaxis with TMP-SMX is initiated solely because of travel.

Treating Disease

Empiric Therapy

In most situations, treatment of diarrheal disease in HIV-infected patients does not differ significantly from that in immunocompetent individuals. Decisions on therapy depend on an assessment of diarrhea severity and hydration status. Patients should be informed of the importance of maintaining hydration and given oral or intravenous (IV) rehydration if indicated (AIII). Because diarrheal disease can produce temporary malabsorption or lactose intolerance, consuming a bland diet and avoiding fat, dairy, and complex carbohydrates also are likely to be useful (BIII). The effectiveness and safety of probiotics or antimotility agents have not been adequately studied in HIV-infected patients with diarrheal illnesses.21 Antimotility agents should be avoided if there is concern about inflammatory diarrhea including CDI (BIII).

After obtaining stool samples for diagnostic evaluation, initiation and duration of empiric antimicrobial therapy depend upon the patient’s CD4 count and clinical appearance. If stool samples are obtained, antibiotic susceptibility testing should be considered to confirm and inform antibiotic choice. No further work-up may be necessary and no treatment other than oral rehydration required, for example, in patients with CD4 counts >500 cells/mm3 who have had 1 to 2 days of loose stools without fever or blood. However, a short course of antibiotics may be indicated in HIV-infected patients with CD4 counts of 200 to 500 cells/mm3 who have diarrhea severe enough to compromise quality of life or ability to work. Patients with advanced HIV disease, that is, CD4 counts <200 cells/mm3 or concomitant AIDS-defining illness, with clinically severe diarrhea (i.e., ≥6 stools per day or bloody stools and/or accompanied by fever or chills) should undergo diagnostic evaluation to determine the etiology of the diarrheal illness and receive antimicrobial treatment. Empiric therapy with a fluoroquinolone is reasonable (AIII). IV ceftriaxone or IV cefotaxime are reasonable alternatives (BIII). Therapy should be adjusted subsequently based on the results of the diagnostic work-up. Diarrhea that is persistent (i.e., lasting >14 days) in the absence of other clinical signs of severity, such as bloody stool or dehydration, should be evaluated and directed therapy should be started once a diagnosis is confirmed.

Diarrhea is one of the most common illnesses affecting international travelers. Antimicrobial resistance among enteric bacterial pathogens outside the United States is an important public health problem. For example, in 2007, 85% of C. jejuni isolates in Southeast Asia were reported as fluoroquinolone resistant.22 Clinicians should consider the possibility of a resistant infection when prescribing empiric therapy for HIV-infected travelers who experience diarrhea while traveling or upon returning to the United States.

Pathogen-Specific Therapy

Salmonella spp.
Immunocompetent hosts who are not HIV-infected often do not require treatment for Salmonella gastroenteritis, as the condition is usually self-limited and treatment may prolong the carrier state. In contrast, most specialists recommend treating Salmonella infections in HIV-infected patients (AIII), although no clinical trials have compared antimicrobial therapy with placebo. Notably, HIV infection increases the risk of Salmonella bacteremia 20- to 100-fold and mortality as much as 7-fold compared with that in patients who are not HIV-infected.1,23

The initial treatment of choice for Salmonella infection is a fluoroquinolone (AIII). Ciprofloxacin is the preferred agent (AIII).24 Other fluoroquinolones, such as levofloxacin and moxifloxacin, likely would be effective in treating salmonellosis in HIV-infected patients but they have not been well evaluated in clinical studies (BIII). Depending on antibiotic susceptibility, alternatives to the fluoroquinolones might include TMP-SMX or expanded-spectrum cephalosporins such as ceftriaxone or cefotaxime (BIII).

The optimal duration of therapy for HIV-related Salmonella infection has not been defined. For patients with CD4 counts >200 cells/mm3 who have mild gastroenteritis without bacteremia, 7 to 14 days of treatment is reasonable. For the same patients with bacteremia, 14 days is appropriate, provided clearance of bacteremia is documented. Longer treatment is suggested if bacteremia persists or if the infection is complicated, that is, if metastatic foci are present (BIII). For patients with advanced HIV disease (CD4 count <200 cells/mm3), 2 to 6 weeks of antibiotics often is recommended (CIII).25 Some patients with Salmonella bacteremia may remain febrile for 5 to 7 days despite effective therapy.

HIV-infected patients with Salmonella bacteremia, which typically occurs in those with advanced HIV disease, should be monitored clinically for recurrence after treatment (BIII). Recurrence may present as bacteremia or as an anatomically localized infection, including intra-abdominal, endothelial, urinary tract, soft tissue, bone and joint, lung, or meningeal foci. Secondary prophylaxis should be considered for patients with recurrent Salmonella bacteremia (CIII), it might also be considered for patients with recurrent gastroenteritis (with or without bacteremia) and in those with CD4 counts <200 cell/mm3 with severe diarrhea (CIII). The value of this secondary prophylaxis has not been established and must be weighed against the risks of long-term antibiotic exposure. Recurrent Salmonella bacteremia constitutes an AIDS-defining illness26 and suppression of HIV replication with ART is expected to decrease the risk of recurrent illnesses. In patients whose Salmonella infection is resolved and who have responded to ART with sustained viral suppression and CD4 counts >200 cells/mm3, secondary prophylaxis for salmonellosis can probably be stopped (CII).7 Clinicians also should be aware that recurrence may represent development of antimicrobial resistance during therapy. 

Shigella spp. 
Therapy for Shigella infections is recommended both to shorten the duration of illness and to possibly prevent spread of the infection to others (AIII).24 The recommended treatment is with a fluoroquinolone, preferably ciprofloxacin, for 7 to 10 days (AIII). Depending on antibiotic susceptibilities, alternative agents might include TMP-SMX (7–10 days) or azithromycin (5 days) (BIII). Azithromycin has not been evaluated in HIV-infected patients with shigellosis, and the therapy suggested is extrapolated from limited data in immunocompetent hosts.27 Treatment for patients with Shigella bacteremia is less well defined, but extending treatment to at least 14 days is reasonable (BIII). Azithromycin is not recommended for treatment of Shigella spp. bacteremia (AIII). Chronic suppressive or maintenance therapy is not recommended for first-time Shigella infections (BIII). Recurrent infections can occur, particularly in persons with CD4 counts < 200 cells/mm3, in which case extending antimicrobial therapy for up to 6 weeks is reasonable (BIII). As with Salmonella infections, suppression of HIV replication with ART is expected to decrease the risk of recurrent shigellosis.

Campylobacter spp. 
The optimal treatment of campylobacteriosis in HIV-infected patients is poorly defined. Culture and susceptibility of Campylobacter isolates is recommended (BIII); in 2009, 22% of Campylobacter isolates in the United States were fluoroquinolone resistant ( For patients with mild disease and CD4 counts >200 cells/mm3, some clinicians opt to withhold therapy unless symptoms persist for more than several days (CIII). For mild-to-moderate campylobacteriosis, initiating therapy with a fluoroquinolone such as ciprofloxacin for 7 to 10 days (if the organism is sensitive) or azithromycin for 5 days is a reasonable approach (BIII). Azithromycin has not been evaluated in HIV-infected patients with campylobacteriosis and the therapy suggested is extrapolated from limited data in immunocompetent hosts.28 Patients with Campylobacter bacteremia should be treated for at least 14 days using a fluoroquinolone if the isolate is sensitive (BIII). Azithromycin is not recommended for treatment of Campylobacter bacteremia (AIII). Adding a second active agent, such as an aminoglycoside, may be prudent in these patients to limit the emergence of antibiotic resistance (BIII). Antibiotic choice should be guided by antibiotic susceptibility tests. Chronic suppressive or maintenance therapy is not recommended for first-time Campylobacter infections in HIV-infected patients (BIII). However, recurrent infections can occur, particularly in patients with CD4 counts <200 cells/mm3. In recurrent disease, extending the length of antimicrobial therapy for 2 to 6 weeks is reasonable (BIII). As with Salmonella infections, suppression of HIV replication with ART is expected to decrease the risk of recurrent Campylobacter spp. infections.

Clostridium difficile 
Treatment of CDI in HIV-infected patients is the same as in patients who are not HIV infected. Guidelines for the treatment of CDI have been published29 and can be consulted for further information.

Special Considerations with Regard to Starting ART  

ART initiation should follow standard guidelines, the presence of a diarrheal illness is relevant only in terms of a patient’s ability to ingest and absorb ART. If recurrent enteric infections are documented and/or Salmonella bacteremia occurs, prompt initiation of ART should be considered regardless of CD4 count; i.e., the presence of an enteric infection should not delay ART initiation (BIII).

Monitoring of Response to Therapy and Adverse Events (Including IRIS)

Patients should be monitored closely for response to treatment, defined clinically by improvement in systemic signs and symptoms, resolution of diarrhea, and sterilization of infected tissues or body fluids such as blood. A follow-up stool culture to demonstrate clearance of the organism is not required if clinical symptoms and diarrhea resolve. Follow-up stool culture may be required when public health considerations and state law dictate the need to ensure micro¬biologic cure, such as in healthcare or food service workers. 

Immune reconstitution inflammatory syndrome (IRIS) has not been described in association with treatment for bacterial enteric pathogens.

Managing Treatment Failure

Follow-up stool culture should be considered for patients who fail to respond clinically to appropriate antimicrobial therapy. In patients with persistent or recurrent diarrhea despite therapy, clinicians should consider other enteric infections in the context of the patient’s immune status and, in all cases, the possibility of C. difficile or the development of antimicrobial resistance. 

Observational studies suggest that plasma drug concentrations (e.g., of ciprofloxacin) in HIV-infected patients may be decreased as a result of diarrhea or malabsorption.30,31 Coadministration of quinolones with magnesium- or aluminum-containing antacids or with calcium, zinc, or iron should be avoided because these interfere with drug absorption. Although larger prospective studies are needed to determine the impact of severe diarrhea on antibiotic absorption, it is prudent to use IV antibiotics in clinically unstable patients (AIII).

Preventing Recurrence

The pharmacologic approach to recurrent enteric infections is covered in the section on directed therapy for each bacterial species. As noted above, secondary prophylaxis should be considered for patients with recurrent Salmonella bacteremia (CIII) and those with recurrent shigellosis (BIII) or campylobacteriosis (BIII).

Special Considerations During Pregnancy

The diagnosis of bacterial enteric infection in pregnant women is the same as in women who are not pregnant. Bacterial enteric infections in pregnant women should be managed the same as in women who are not pregnant, with several considerations. Based on the safety profile, expanded-spectrum cephalosporins or azithromycin should be the first-line therapy for bacterial enteric infections during pregnancy if antimicrobials are required, depending on the organism and the results of susceptibility testing (BIII). Arthropathy has been noted in the offspring of animals treated with quinolones during pregnancy. However, studies evaluating quinolone use in pregnant women did not find an increased risk of birth defects or musculoskeletal abnormalities.32,33 Thus, quinolones can be used in pregnancy for bacterial enteric infections in HIV-infected pregnant women if indicated by susceptibility testing or failure of first-line therapy, as listed above (BIII). TMP-SMX use in the first trimester should be avoided, if possible, because of an association with an increased risk of birth defects, specifically neural tube, cardiovascular, and urinary tract defects (BIII).34-36 Neonatal care providers should be informed if maternal sulfa therapy was used near delivery because of the theoretical increased risk to the newborn of hyperbilirubinemia and kernicterus.


Recommendations for Treating Bacterial Enteric Infections

No title

General Considerations when Managing Patients with Bacterial Enteric Infections
  • Oral or IV hydration therapy (if indicated) should be given to patients with diarrhea (AIII).
  • Diagnostic fecal specimens should be obtained prior to initiation of empiric antimicrobial therapy.
  • Antibiotic suceptibilties should be obtained to confirm and inform antibiotic choice.
  • Risk of a bacterial enteric infection increases as CD4 declines with greatest risk with CD4 <200 cells/mm3. Risk of bacteremia also increases with decreasing CD4 count.
  • Anti-motility agents should be avoided if there is concern about inflammatory diarrhea including Clostridium difficile infection (BIII)
  • If no clinical response after 5 to 7 days, consider follow-up stool culture with antibiotic susceptibility testing and other methods to detect enteric pathogens (e.g., toxin assays, molecular methods), alternative diagnosis, antibiotic resistance, or drug-drug interactions.
  • Effective ART may reduce the frequency, severity, and recurrence of bacterial enteric infections.
Empiric Treatment of Bacterial Enteric Infections (Pending Diagnostic Studies)

For patients with advanced HIV (CD4 <200 cells/mm3 or concomitant AIDS-defining illnesses) and clinically severe diarrhea (≥6 stools/day or bloody stool and/or accompanied fever or chills).

Preferred Therapy:
  • Ciprofloxacin 500–750 mg PO (or 400 mg IV) q12h (AIII)
Alternative Therapy:
  • Ceftriaxone IV 1 gm q24h (BIII)
  • Cefotaxime IV 1gm q8h (BIII)
Note: IV antibiotic therapy with hospitalization should be considered in patients with marked nausea, vomiting, diarrhea, electrolyte abnormalities, acidosis, blood pressure instability, and/or when clinical judgment indicates severity of disease.

For patients with persistent diarrhea (>14 days) in the absence of other severe clinical signs (e.g., dehydration, blood in stool)—can withhold antibiotic therapy until a diagnosis is confirmed.

Diarrhea is a common illness of internationl travelers. Antimicrobial resistance among enteric bacterial pathogens outside the United States is common. Clinicians should consider the possibility of resistant infections when prescribing empiric antibiotic therapy for HIV infected travelers while traveling or upon return to the United States.
Treating Salmonellosis

All HIV-infected patients with salmonellosis should receive antibiotic treatment due to the increased risk of bacteremia in these patients (AIII).

Preferred Therapy for Salmonella Gastroenteritis With or Without Bacteremia:
  • Ciprofloxacin 500–750 mg PO (or 400 mg IV) q12h (AIII)
Alternative Therapy:
  • Levofloxacin 750 mg (PO or IV) q24h (BIII), or
  • Moxifloxacin 400 mg (PO or IV) q24h (BIII), or
  • Trimethoprim 160 mg/sulfamethoxazole 800 mg (PO or IV) q12h (BIII), or
  • Ceftriaxone IV 1gm q24h (BIII), or
  • Cefotaxime IV 1gm q8h (BIII)
Duration of Therapy for Gastroenteritis Without Bacteremia
  • If CD4 count ≥200 cells/mm3: 7–14 days (BIII)
  • If CD4 count <200 cells/mm3: 2–6 weeks (CIII)
Duration of Therapy for Gastroenteritis with Bacteremia
  • If CD4 count ≥200 cells/mm3: 14 days (AIII); longer duration if bacteremia persists or if the infection is complicated (e.g., metastatic foci of infection are present) (BIII)
  • If CD4+ count <200 cells/mm3: 2–6 weeks (BIII)
Secondary Prophylaxis

Indications: The role of long-term, secondary prophylaxis for patients with recurrent bacteremia is not well established. The clinician must weigh the benefit against the risks of long-term antibiotic exposure (CIII). Clinicians should be aware that recurrence may represent development of antimicrobial resistance during therapy.

Some Experts Recommend Secondary Prophylaxis For:
  • Patients with recurrent gastroenteritis +/- bacteremia or those with CD4 <200 cells/µL and severe diarrhea (CIII)
When To Stop Secondary Prophylaxis:
  • After resolution of Salmonella infection, responded to ART with sustained viral suppression and CD4 count >200 cells/µL (CII)
Treating Shigellosis

Therapy is indicated to shorten the duration of illness and to possibly prevent spread to others (AIII).

Preferred Therapy:
  • Ciprofloxacin 500–750 mg PO (or 400 mg IV) q12h (AIII)
Alternative Therapy (Depending on Susceptibility Results):
  • Levofloxacin 750 mg (PO or IV) q24h (BIII); or
  • Moxifloxacin (PO or IV) 400 mg q24h (BIII)
  • Trimethoprim 160 mg/sulfamethoxazole 800 mg PO or IV q12h (BIII)—if susceptible
  • Azithromycin 500 mg PO daily for 5 days (BIII) (Note: azithromycin is not recommended for Shigella bacteremia [AIII])
Duration of Therapy:
  • Gastroenteritis: 7–10 days (AIII) (except azithromycin, treat for 5 days)
  • Bacteremia: ≥14 days (BIII)
  • Recurrent Infections: up to 6 weeks (BIII)
Chronic Maintenance or Suppressive Therapy:
  • Not recommended for first time Shigella infections (BIII)
Treating Campylobacteriosis
  • Optimal treatment is poorly defined.
  • There is an increasing rate of fluoroquinolone resistance in the United States (22% resistance in 2009)
  • Antimicrobial therapy should be modified based on susceptibility reports.
Mild disease if CD4 count > 200 cells/mm3:
  • Withhold therapy and monitor (CIII)
Mild to Moderate Disease:
Preferred Therapy:
  • Ciprofloxacin 500–750 mg PO (or 400 mg IV) q12h (BIII)—if susceptible, or
  • Azithromycin 500 mg PO daily for 5 days (BIII) (note: avoid azithromycin with bacteremia, [AIII])
Alternative Therapy (Depending on Susceptibility Results):
  • Levofloxacin 750 mg PO or IV q24h (BIII); or
  • Moxifloxacin 400 mg PO or IV q24h (BIII)
  • Ciprofloxacin 500–750 mg PO (or 400 mg IV) q12h (BIII) + an aminoglycoside (BIII) in bacteremic patients to enhance therapeutic effectiveness and/or limit the emergence of antibiotic resistance
Duration of Therapy:
  • Gastroenteritis: 7–10 days (BIII) [5 days if azithromycin is used]
  • Bacteremia: >14 days (BIII)
  • Recurrent bacteremic disease: 2–6 weeks (BIII)
Chronic Maintenance or Suppressive Therapy:

  • Not recommended for first time Campylobacter infections (BIII)
Key to Acronyms: CD4 = CD4 T lymphocyte cell; IV = intraveniously; PO = orally; q(n)h = every “n” hours. 


  1. Celum CL, Chaisson RE, Rutherford GW, Barnhart JL, Echenberg DF. Incidence of salmonellosis in patients with AIDS. J Infect Dis. Dec 1987;156(6):998-1002. Available at
  2. Sorvillo FJ, Lieb LE, Waterman SH. Incidence of campylobacteriosis among patients with AIDS in Los Angeles County. J Acquir Immune Defic Syndr. 1991;4(6):598-602. Available at
  3. Angulo FJ, Swerdlow DL. Bacterial enteric infections in persons infected with human immunodeficiency virus. Clin Infect Dis. Aug 1995;21 Suppl 1:S84-93. Available at
  4. Nelson MR, Shanson DC, Hawkins DA, Gazzard BG. Salmonella, Campylobacter and Shigella in HIV-seropositive patients. AIDS. Dec 1992;6(12):1495-1498. Available at
  5. Sanchez TH, Brooks JT, Sullivan PS, et al. Bacterial diarrhea in persons with HIV infection, United States, 1992-2002. Clin Infect Dis. Dec 1 2005;41(11):1621-1627. Available at
  6. Wilcox CM, Saag MS. Gastrointestinal complications of HIV infection: changing priorities in the HAART era. Gut. Jun 2008;57(6):861-870. Available at
  7. Hung CC, Hung MN, Hsueh PR, et al. Risk of recurrent nontyphoid Salmonella bacteremia in HIV-infected patients in the era of highly active antiretroviral therapy and an increasing trend of fluoroquinolone resistance. Clin Infect Dis. Sep 1 2007;45(5):e60-67. Available at
  8. Huang DB, Mohanty A, DuPont HL, Okhuysen PC, Chiang T. A review of an emerging enteric pathogen: enteroaggregative Escherichia coli. Journal of medical microbiology. Oct 2006;55(Pt 10):1303-1311. Available at
  9. Aragon TJ, Vugia DJ, Shallow S, et al. Case-control study of shigellosis in San Francisco: the role of sexual transmission and HIV infection. Clin Infect Dis. Feb 1 2007;44(3):327-334. Available at
  10. Quinn TC, Goodell SE, Fennell C, et al. Infections with Campylobacter jejuni and Campylobacter-like organisms in homosexual men. Ann Intern Med. Aug 1984;101(2):187-192. Available at
  11. Snijders F, Kuijper EJ, de Wever B, van der Hoek L, Danner SA, Dankert J. Prevalence of Campylobacter-associated diarrhea among patients infected with human immunodeficiency virus. Clin Infect Dis. Jun 1997;24(6):1107-1113. Available at
  12. Tee W, Mijch A. Campylobacter jejuni bacteremia in human immunodeficiency virus (HIV)-infected and non-HIV-infected patients: comparison of clinical features and review. Clin Infect Dis. Jan 1998;26(1):91-96. Available at
  13. Tee W, Mijch A, Wright E, Yung A. Emergence of multidrug resistance in Campylobacter jejuni isolates from three patients infected with human immunodeficiency virus. Clin Infect Dis. Sep 1995;21(3):634-638. Available at
  14. Meier PA, Dooley DP, Jorgensen JH, Sanders CC, Huang WM, Patterson JE. Development of quinolone-resistant Campylobacter fetus bacteremia in human immunodeficiency virus-infected patients. J Infect Dis. Apr 1998;177(4):951-954. Available at
  15. Casado JL, Valdezate S, Calderon C, et al. Zidovudine therapy protects against Salmonella bacteremia recurrence in human immunodeficiency virus-infected patients. J Infect Dis. Jun 1999;179(6):1553-1556. Available at 
  16. Kristjansson M, Viner B, Maslow JN. Polymicrobial and recurrent bacteremia with Shigella in a patient with AIDS. Scandinavian journal of infectious diseases. 1994;26(4):411-416. Available at
  17. Mayer KH, Hanson E. Recurrent salmonella infection with a single strain in the acquired immunodeficiency syndrome. Confirmation by plasmid fingerprinting. Diagn Microbiol Infect Dis. Jan 1986;4(1):71-76. Available at
  18. Rubino S, Spanu L, Mannazzu M, et al. Molecular typing of non-typhoid Salmonella strains isolated from HIV-infected patients with recurrent salmonellosis. AIDS. Jan 14 1999;13(1):137-139. Available at
  19. Pulvirenti JJ, Mehra T, Hafiz I, et al. Epidemiology and outcome of Clostridium difficile infection and diarrhea in HIV infected inpatients. Diagn Microbiol Infect Dis. Dec 2002;44(4):325-330. Available at
  20. Schneider E, Whitmore S, Glynn KM, et al. Revised surveillance case definitions for HIV infection among adults, adolescents, and children aged <18 months and for HIV infection and AIDS among children aged 18 months to <13 years--United States, 2008. MMWR Recomm Rep. Dec 5 2008;57(RR-10):1-12. Available at
  21. Nwachukwu CE, Okebe JU. Antimotility agents for chronic diarrhoea in people with HIV/AIDS. Cochrane Database Syst Rev. 2008(4):CD005644. Available at
  22. Tribble DR, Sanders JW, Pang LW, et al. Traveler's diarrhea in Thailand: randomized, double-blind trial comparing single-dose and 3-day azithromycin-based regimens with a 3-day levofloxacin regimen. Clin Infect Dis. Feb 1 2007;44(3):338-346. Available at
  23. Cummings PL, Sorvillo F, Kuo T. Salmonellosis-related mortality in the United States, 1990-2006. Foodborne Pathog Dis. Nov 2010;7(11):1393-1399. Available at
  24. Guerrant RL, Van Gilder T, Steiner TS, et al. Practice guidelines for the management of infectious diarrhea. Clin Infect Dis. Feb 1 2001;32(3):331-351. Available at
  25. Gordon MA, Banda HT, Gondwe M, et al. Non-typhoidal salmonella bacteraemia among HIV-infected Malawian adults: high mortality and frequent recrudescence. AIDS. Aug 16 2002;16(12):1633-1641. Available at
  26. 1993 revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. MMWR Recomm Rep. Dec 18 1992;41(RR-17):1-19. Available at
  27. Khan WA, Seas C, Dhar U, Salam MA, Bennish ML. Treatment of shigellosis: V. Comparison of azithromycin and ciprofloxacin. A double-blind, randomized, controlled trial. Ann Intern Med. May 1 1997;126(9):697-703. Available at
  28. Kuschner RA, Trofa AF, Thomas RJ, et al. Use of azithromycin for the treatment of Campylobacter enteritis in travelers to Thailand, an area where ciprofloxacin resistance is prevalent. Clin Infect Dis. Sep 1995;21(3):536-541. Available at
  29. Cohen SH, Gerding DN, Johnson S, et al. Clinical practice guidelines for Clostridium difficile infection in adults: 2010 update by the society for healthcare epidemiology of America (SHEA) and the infectious diseases society of America (IDSA). Infect Control Hosp Epidemiol. May 2010;31(5):431-455. Available at
  30. Gurumurthy P, Ramachandran G, Hemanth Kumar AK, et al. Malabsorption of rifampin and isoniazid in HIV-infected patients with and without tuberculosis. Clin Infect Dis. Jan 15 2004;38(2):280-283. Available at
  31. Peloquin CA, MacPhee AA, Berning SE. Malabsorption of antimycobacterial medications. N Engl J Med. Oct 7 1993;329(15):1122-1123. Available at
  32. Schaefer C, Amoura-Elefant E, Vial T, et al. Pregnancy outcome after prenatal quinolone exposure. Evaluation of a case registry of the European Network of Teratology Information Services (ENTIS). Eur J Obstet Gynecol Reprod Biol. Nov 1996;69(2):83-89. Available at
  33. Loebstein R, Addis A, Ho E, et al. Pregnancy outcome following gestational exposure to fluoroquinolones: a multicenter prospective controlled study. Antimicrob Agents Chemother. Jun 1998;42(6):1336-1339. Available at
  34. Czeizel AE, Rockenbauer M, Sorensen HT, Olsen J. The teratogenic risk of trimethoprim-sulfonamides: a population based case-control study. Reprod Toxicol. Nov-Dec 2001;15(6):637-646. Available at
  35. Hernandez-Diaz S, Werler MM, Walker AM, Mitchell AA. Folic acid antagonists during pregnancy and the risk of birth defects. N Engl J Med. Nov 30 2000;343(22):1608-1614. Available at
  36. Hernandez-Diaz S, Werler MM, Walker AM, Mitchell AA. Neural tube defects in relation to use of folic acid antagonists during pregnancy. American journal of epidemiology. May 15 2001;153(10):961-968. Available at

Back to Top