eMedicine Specialties > Pediatrics: General Medicine > Infectious Disease
Shigella Infection: Treatment & Medication
Updated: Jul 31, 2008
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
Treatment
Medical Care
The clinician should rapidly assess the patient's fluid and electrolyte status and institute parenteral or oral hydration along with antipyretics as needed. Prompt recognition and treatment of seizures and raised intracranial pressure are essential. Nutritional supplementation of vitamin A (200,000 IU) can hasten clinical resolution in malnourished children.
Surgical Care
Surgical care may be required for complications (eg, intestinal perforation).
Consultations
- Consult a neurologist if seizures and altered sensorium predominate.
- Consult a nephrologist if HUS is suspected (eg, for patients with anemia, thrombocytopenia, oliguria, and renal failure).
Diet
The diet may need to be restricted according to the severity of the disease.
Activity
No restrictions are necessary.
Medication
Various antimicrobial agents are effective in the treatment of shigellosis, although options are becoming limited because of globally emerging drug resistance. Resistance of Shigella species to sulfonamides, tetracyclines, ampicillin, and trimethoprim-sulfamethoxazole (TMP-SMX) has been reported worldwide, and these agents are not recommended as empirical therapy. Most clinical infections with S sonnei are self-limited (48-72 h) and may not require antimicrobial therapy.
Because shigellosis is self-limiting, some authorities recommend withholding antibiotic therapy. However, even if not fatal, the untreated illness may cause chronic or recurrent diarrhea, making a child quite ill for several weeks; this may lead to malnutrition, especially in developing countries. The risk of continued shedding of organisms in stool increases the risk of transmission of further disease among contacts argues against withholding antimicrobial treatment.
Presently, no US Food and Drug Administration (FDA)–approved vaccines are available.
Antimicrobial therapy is typically administered for 5 days. Antibiotic treatment decreases the duration of illness, person-to-person spread, and cases in household contacts. Treatment in malnourished children (eg, in developing countries) is likely to reduce the risk of worsening malnutrition morbidity after shigellosis. In persons infected with S dysenteriae type 1, early administration of effective antibiotics is decreases Stx concentrations in the stool and lowers the risk of HUS. However, the risk of HUS caused by E coli O157-H7 may be increased with the early administration of antibiotics. Prophylactic antibiotics are not recommended for contacts.
Antidiarrheal medications (diphenoxylate hydrochloride with atropine [Lomotil] or loperamide) should not be used because of the risk of prolonging the illness.
A child with typical dysentery that responds to initial empirical antibiotic treatment should continue taking the same drug for a full 5-day course, even if the stool culture is negative.
Nutritional supplementation including vitamin A (200,000 IU) and zinc (20 mg/d for 14 d)4 may be administered to hasten the clinical recovery and immune response in the settings of malnutrition or in certain geographic areas.
Antibiotics
Ampicillin and TMP-SMZ are effective for susceptible strains; amoxicillin is less effective than this because of its rapid absorption high in the GI tract. The oral route is preferred except for seriously ill patients. In the United States, sentinel surveillance data from 1999-2000 indicated that 54% of S sonnei and 47% of S flexneri organisms were resistant to ampicillin and TMP-SMZ. Ampicillin (but not amoxicillin) is still the drug of choice if the isolate is susceptible to this drug.
If ampicillin and TMP-SMZ resistant strain is isolated or if susceptibility is unknown, parenteral ceftriaxone sodium, a fluoroquinolone (eg, ciprofloxacin, ofloxacin), or azithromycin dihydrate are the drugs of choice. Fluoroquinolones are typically not administered to children and adolescents younger than 18 years unless other antibiotic choices are not suitable.
Trimethoprim and sulfamethoxazole (Bactrim, Cotrim)
Combination effective for shigellosis. Produces sequential blockade in folic acid synthesis. Effect frequently synergistic and bactericidal.
Adult
>40 kg: 160 mg/dose PO bid (based on TMP component)
Pediatric
<2 months: Contraindicated
>2 months: 8-10 mg/kg/d PO divided bid for 5 d (based on TMP dose)
May increase PT when used with warfarin (perform coagulation tests and adjust dose accordingly); coadministration with dapsone may increase blood levels of both; coadministration of diuretics increases incidence of thrombocytopenia purpura in elderly patients; phenytoin levels may increase with coadministration; may potentiate effects of methotrexate in bone marrow depression; hypoglycemic response to sulfonylureas may increase with coadministration; may increase levels of zidovudine
Documented hypersensitivity; megaloblastic anemia caused by folate deficiency; glucose-6-phosphate dehydrogenase (G-6-PD) deficiency; age <2 mo; last trimester of pregnancy (due to potential toxicity to newborn, eg, jaundice, hemolytic anemia, kernicterus)
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Discontinue at first appearance of rash or sign of adverse reaction; caution in patients with renal and/or hepatic dysfunction; maintain adequate fluid intake to prevent crystalluria and renal stone formation
Ampicillin (Principen)
Broad-spectrum penicillin. Interferes with bacterial cell-wall synthesis during active replication, causing bactericidal activity against susceptible organisms.
Adult
250-500 mg PO q6h
Pediatric
50-100 mg/kg/d PO divided q4-6h; not to exceed 3 g/d
Probenecid and disulfiram elevate levels; allopurinol decreases effects and has additive effects on ampicillin-related rash; may decrease effects of PO contraceptives
Documented hypersensitivity
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Adjust dose in renal failure; evaluate rash and differentiate from hypersensitivity reaction
Ceftriaxone (Rocephin)
Third-generation cephalosporin. Blocks transpeptidase activity of penicillin-binding proteins (PBP). Used in patients with contraindications to TMP-SMZ.
Adult
2 g IV/IM as a single dose or in 2 divided doses
Pediatric
50 mg/kg/d IV/IM as a single daily dose for empiric treatment; continue for 5 d for treatment regimen
Probenecid may increase levels; coadministration with ethacrynic acid, furosemide, and aminoglycosides may increase nephrotoxicity
Documented hypersensitivity
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
History of penicillin allergy; rashes; thrombophlebitis; GI upset with nausea, vomiting, and diarrhea
Azithromycin (Zithromax)
Acts by binding to 50S ribosomal subunit of susceptible microorganisms and blocks dissociation of peptidyl tRNA from ribosomes, causing RNA-dependent protein synthesis to arrest. Nucleic acid synthesis not affected. Concentrates in phagocytes and fibroblasts, as demonstrated with in vitro incubation techniques. In vivo data suggest that concentration in phagocytes may contribute to drug distribution to inflamed tissues. Used to treat mild-to-moderate microbial infections.
Adult
Day 1: 500 mg PO
Days 2-5: 250 mg PO qd
Pediatric
Day 1: 12 mg/kg PO as a single dose
Days 2-5: 6 mg/kg PO qd
May increase toxicity of theophylline, warfarin, and digoxin; effects are reduced with coadministration of aluminum and/or magnesium antacids; nephrotoxicity and neurotoxicity may occur when coadministered with cyclosporine
Documented hypersensitivity; hepatic impairment; do not administer with pimozide
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
May increase hepatic enzyme levels and cause cholestatic jaundice; caution in impaired hepatic function, prolonged QT intervals, or pneumonia; caution in hospitalized, geriatric, or debilitated patients
Nalidixic acid (NegGram)
First-generation quinolone. Blocks bacterial DNA gyrase. Useful in patients with sulfas and cephalosporin allergy.
Adult
1 g PO q6h
Pediatric
55 mg/kg/d PO in 4 divided doses for 5 d
Potentiates warfarin effect; antacids decrease absorption
Documented hypersensitivity, convulsive disorders, infants <3 months
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Caution in patients with impaired renal and hepatic function, G-6-PD deficiency; may cause gastrointestinal intolerance, rashes, photosensitivity; cartilage degeneration (animals)
More on Shigella Infection |
| Overview: Shigella Infection |
| Differential Diagnoses & Workup: Shigella Infection |
 Treatment & Medication: Shigella Infection |
| Follow-up: Shigella Infection |
| References |
| « Previous Page | Next Page » |
References
CDC. Preliminary FoodNet data on the incidence of infection with pathogens transmitted commonly through food--10 states, 2007. MMWR Morb Mortal Wkly Rep. Apr 11 2008;57(14):366-70. [Medline]. [Full Text].
Baer JT, Vugia DJ, Reingold AL, et al. HIV infection as a risk factor for shigellosis. Emerg Infect Dis. Nov-Dec 1999;5(6):820-3. [Medline].
Khan WA, Dhar U, Salam MA, et al. Central nervous system manifestations of childhood shigellosis: prevalence, risk factors, and outcome. Pediatrics. Feb 1999;103(2):E18. [Medline].
Rahman MJ, Sarkar P, Roy SK. Effect of zinc supplementation as adjunct therapy on the systemic immune response in shigellosis. Am J Clin Nutr. Feb, 2005;81(2):495-502. [Medline].
Basualdo W, Arbo A. Randomized comparison of azithromycin versus cefixime for treatment of shigellosis in children. Pediatr Infect Dis J. Apr 2003;22(4):374-7. [Medline].
Bennish ML, Khan WA, Begum M, et al. Low risk of hemolytic uremic syndrome after early effective antimicrobial therapy for Shigella dysenteriae type 1 infection in Bangladesh. Clin Infect Dis. Feb 1 2006;42(3):356-62. [Medline].
Edwards BH. Salmonella and Shigella species. Clin Lab Med. Sep 1999;19(3):469-87, v. [Medline].
Friedrich AW, Bielaszewska M, Zhang WL, et al. Escherichia coli harboring Shiga toxin 2 gene variants: frequency and association with clinical symptoms. J Infect Dis. Jan 1 2002;185(1):74-84. [Medline].
Gomez HF, Cleary TG. Shigella species. In: Principles and Practice of Pediatric Infectious Diseases. New York, NY: Churchill Livingstone; 1997:429-34.
Gomez HF, Cleary TG. Shigella. In: Textbook of Pediatric Infectious Diseases. Philadelphia, PA: WB Saunders; 1998:1207-317.
Huicho L, Sanchez D, Contreras M, et al. Occult blood and fecal leukocytes as screening tests in childhood infectious diarrhea: an old problem revisited. Pediatr Infect Dis J. Jun 1993;12(6):474-7. [Medline].
Ingersoll MA, Zychlinsky A. ShiA abrogates the innate T-cell response to Shigella flexneri infection. Infect Immun. Apr 2006;74(4):2317-27. [Medline].
Katz DE, Coster TS, Wolf MK, et al. Two studies evaluating the safety and immunogenicity of a live, attenuated Shigella flexneri 2a vaccine (SC602) and excretion of vaccine organisms in North American volunteers. Infect Immun. Feb 2004;72(2):923-30. [Medline].
Keusch GT, Jacewicz M, Acheson DW, et al. Globotriaosylceramide, Gb3, is an alternative functional receptor for Shiga-like toxin 2e. Infect Immun. Mar 1995;63(3):1138-41. [Medline].
Mitra AK, Alvarez JO, Wahed MA, et al. Predictors of serum retinol in children with shigellosis. Am J Clin Nutr. Nov 1998;68(5):1088-94. [Medline].
Nataro JP. Treatment of bacterial enteritis. Pediatr Infect Dis J. May 1998;17(5):420-1. [Medline].
Nathoo KJ, Porteous JE, Siziya S, et al. Predictors of mortality in children hospitalized with dysentery in Harare, Zimbabwe. Cent Afr J Med. Nov 1998;44(11):272-6. [Medline].
Navia MM, Gascon J, Vila J. Analysis of the mechanisms of resistance to several antimicrobial agents in Shigella spp. causing travellers' diarrhoea. Clin Microbiol Infect. Dec 2005;11(12):1044-7. [Medline].
Niyogi SK. Shigellosis. J Microbiol. Apr 2005;43(2):133-43. [Medline].
Oaks EV, Turbyfill KR. Development and evaluation of a Shigella flexneri 2a and S. sonnei bivalent invasin complex (Invaplex) vaccine. Vaccine. Mar 20 2006;24(13):2290-301. [Medline].
Ochoa TJ, Cleary TG. Shigella. In: Kliegman, Behrman, Jenson, Stanton, eds. Nelson Textbook of Paediatrics. 18th ed. Philadelphia, PA: Saunders Elsevier; 2007:1191-3.
Pazhani GP, Ramamurthy T, Mitra U, et al. Species diversity and antimicrobial resistance of Shigella spp. isolated between 2001 and 2004 from hospitalized children with diarrhoea in Kolkata (Calcutta), India. Epidemiol Infect. Dec 2005;133(6):1089-95. [Medline].
Plotz FB, Arets HG, Fleer A, et al. Lethal encephalopathy complicating childhood shigellosis. Eur J Pediatr. Jul 1999;158(7):550-2. [Medline].
Richardson SE, Rotman TA, Jay V, et al. Experimental verocytotoxemia in rabbits. Infect Immun. Oct 1992;60(10):4154-67. [Medline].
Tzipori S, Sheoran A, Akiyoshi D, et al. Antibody therapy in the management of shiga toxin-induced hemolytic uremic syndrome. Clin Microbiol Rev. Oct 2004;17(4):926-41, table of contents. [Medline].
Wong CS, Jelacic S, Habeeb RL, et al. The risk of the hemolytic-uremic syndrome after antibiotic treatment of Escherichia coli O157:H7 infections. N Engl J Med. Jun 29 2000;342(26):1930-6. [Medline].
Yang F, Yang J, Zhang X, et al. Genome dynamics and diversity of Shigella species, the etiologic agents of bacillary dysentery. Nucleic Acids Res. 2005;33(19):6445-58. [Medline].
Further Reading
Keywords
Shigella infection, shigellosis, Shigella dysenteriae, S dysenteriae, Shigella dysenteriae, S dysenteriae, Shigella sonnei, S sonnei, Shigella flexneri, S flexneri, Shigella boydii, S boydii, infectivity dose, ID, Shiga toxin, Stx, bacillary dysentery, Escherichia coli, diarrhea, hemolytic-uremic syndrome, dehydration, hypotension, abdominal tenderness, microangiopathic hemolytic anemia, thrombocytopenia, renal failure, septicemia, hypoglycemia, bronchopneumonia, disseminated intravascular coagulation, DIC, cholestatic hepatitis, arthritis, conjunctivitis, urethritis, myocarditis, rectal prolapse, cardiogenic shock, arrhythmias, heart block, bacteremia, rectal prolapse, toxic megacolon
