Table 6.
Recommended Antimicrobial Agents by Pathogen
| Indication | First Choice | Alternative | Comments/Considerations |
|---|---|---|---|
| Bacteriaa | |||
| Campylobacter | Azithromycin | Ciprofloxacin | |
| Clostridium difficile | Oral vancomycin | Fidaxomicin | Fidaxomicin not currently recommended for people <18 years of age. Metronidazole is still acceptable treatment for nonsevere CDI in children and as a second-line agent for adults with nonsevere CDI (eg, who cannot obtain vancomycin or fidaxomicin at a reasonable cost). |
| Nontyphoidal Salmonella entericab | Usually not indicated for uncomplicated infection | NA | Antimicrobial therapy should be considered for groups at increased risk for invasive infection: neonates (up to 3 months old), persons >50 years old with suspected atherosclerosis, persons with immunosuppression, cardiac disease (valvular or endovascular), or significant joint disease. If susceptible, treatment with ceftriaxone, ciprofloxacin, TMP-SMX, or amoxicillin. |
| Salmonella enterica Typhi or Paratyphib | Ceftriaxone or ciprofloxacin | Ampicillin or TMP-SMX or azithromycin | |
| Shigella a | Azithromycinc or ciprofloxacina, or ceftriaxone | TMP-SMX or ampicillin if susceptible | Clinicians treating people with shigellosis for whom antibiotic treatment is indicated should avoid prescribing fluoroquinolones if the ciprofloxacin MIC is 0.12 μg/ mL or higher even if the laboratory report identifies the isolate as susceptible. See https://emergency. cdc.gov/han/han00401.asp |
| Vibrio cholerae | Doxycyclined | Ciprofloxacin, azithromycin, or ceftriaxone | |
| Non–Vibrio choleraed | Usually not indicated for noninvasive disease. Single-agent therapy for noninvasive disease if treated. Invasive disease: ceftriaxone plus doxycycline |
Usually not indicated for noninvasive disease. Single-agent therapy for noninvasive disease if treated. Invasive disease: TMP-SMX plus an aminoglycoside |
|
| Yersinia enterocolitica | TMP-SMX | Cefotaxime or ciprofloxacin | |
| Parasites | |||
| Cryptosporidium spp | Nitazoxanide (HIV-uninfected, HIV-infected in combination with effective cART): | Effective cART: Immune reconstitution may lead to microbiologic and clinical response [154, 209, 210] |
NA |
| Cyclospora cayetanensis | TMP-SMX | Nitazoxanide (limited data) | Patients with HIV infection may require higher doses or longer durations of TMP-SMX treatment |
| Giardia lamblia | • Tinidazole Note: Based on data from HIV-uninfected children • Nitazoxanide |
Metronidazole Note: Based on data from HIV- uninfected children |
• Tinidazole is approved in the United States for children aged ≥3 years. It is available in tablets that can be crushed. • Metronidazole has high frequency of gastrointestinal side effects. A pediatric suspension of metronidazole is not commercially available but can be compounded from tablets. Metronidazole is not FDA approved for the treatment of giardiasis. |
| Cystoisospora belli | TMP-SMX | Pyrimethamine Potential second-line alternatives: • Ciprofloxacin • Nitazoxanide |
|
| Trichinella spp | Albendazole | Alternative: mebendazole | • Therapy less effective in late stage of infection, when larvae encapsulate in muscle |
| Fungus | |||
| Microsporidia | For disseminated (not ocular) and intestinal infection attributed to microsporidia other than Enterocytozoon bieneusi or Vittaforma corneae: • Albendazole after initiation of cART and resolution of signs and symptoms For E. bieneusi or V. corneae infections: • Fumagillin recommended for treatment of infections due to E. bieneusi in HIV-infected adults |
NA | Effective cART therapy: • Immune reconstitution may lead to microbiologic and clinical response • Fumagillin for systemic use is unavailable in the United States and data on dosing in children are unavailable. • Consultation with an expert is recommended. |
Abbreviations: cART, combination antiretroviral therapy; CDI, Clostridium difficile infection; FDA, US Food and Drug Administration; HIV, human immunodeficiency virus; MIC, minimum inhibitory concentration; NA, not applicable; TMP-SMX, trimethoprim-sulfamethoxazole.
aFor information on susceptibility patterns in the United States, see the National Antimicrobial Resistance Monitoring System (NARMS; http://www.cdc.gov/narms). Susceptibility testing should be considered when a therapeutic agent is selected.
bIf invasive disease is suspected or confirmed, ceftriaxone is preferred over ciprofloxacin due to increasing resistance to ciprofloxacin.cMost clinical laboratories do not test for azithromycin susceptibility.
dPrimary therapy is aggressive rehydration; antibiotics are adjunctive therapy.