Pediatric Nocardiosis Medication

Updated: Oct 04, 2013
  • Author: Nicholas John Bennett, MBBCh, PhD, MA(Cantab), FAAP; Chief Editor: Russell W Steele, MD  more...
  • Print
Medication

Antibiotics

Class Summary

The mainstay of nocardiosis therapy are sulfa-based antibiotics (eg, trimethoprim-sulfamethoxazole) given intravenously in high doses. Trimethoprim-sulfamethoxazole has shown less efficacy as a single agent in some AIDS-related nocardial infections. The single best regimen for treatment has not been established, and antibiotic resistance testing is recommended to tailor therapies to the specific strain infecting the patient. Trimethoprim-sulfamethoxazole, amikacin, and either ceftriaxone or imipenem are a reasonable combination of drugs for an initial empiric therapy prior to the results of susceptibility testing.

The use of linezolid to treat resistant or severe infection has been documented and shows promise. [11] Linezolid has been tested in vitro and has been shown to be the first antimicrobial agent to be active against all Nocardia species. It has good CNS penetration, does not require adjustment for renal or liver disease, has few drug interactions (especially with immunosuppressive medications), and has been shown to work as monotherapy against Nocardia. It is also available with excellent bioavailability in an oral form and may become a first-line therapy for Nocardia infection.

Trimethoprim-sulfamethoxazole (Bactrim, Septra)

Inhibits bacterial growth by inhibiting synthesis of dihydrofolic acid. Doses are based on the trimethoprim component.

Imipenem and cilastatin (Primaxin)

Therapy with this alternative agent often is used in combination with amikacin. For CNS nocardiosis, consider the related drug, meropenem, instead.

Amikacin (Amikin)

Used in conjunction with trimethoprim-sulfamethoxazole or imipenem-cilastatin. Peak therapeutic levels are 20-30 mg/L, and trough levels are 5-10 mg/L.

Minocycline (Dynacin, Minocin)

Another alternative drug both in PO and IV formulations for prolonged treatment. However, it is not recommended in children < 8 y.

Amoxicillin and clavulanate (Augmentin)

Aminopenicillin with a beta-lactamase inhibitor. Doses are based on the amoxicillin component. This drug is used as a follow-up treatment PO agent for prolonged therapy following IV treatment with imipenem or meropenem/amikacin. (See trimethoprim-sulfamethoxazole for suggested treatment duration.)

Ampicillin (Marcillin, Omnipen)

Bactericidal activity against susceptible organisms. Alternative to amoxicillin when unable to take PO medication.

Meropenem (Merrem IV)

Bactericidal broad-spectrum carbapenem antibiotic that inhibits cell-wall synthesis. Effective against most gram-positive and gram-negative bacteria.

Has slightly increased activity against gram-negative bacteria and slightly decreased activity against staphylococci and streptococci compared to imipenem. Not recommended for children.

Doxycycline (Bio-Tab, Doryx, Vibramycin)

Inhibits protein synthesis and thus bacterial growth by binding to 30S and, possibly, 50S ribosomal subunits of susceptible bacteria.

Sulfadiazine (Microsulfon)

Exerts bacteriostatic action by competitive antagonism of para-aminobenzoic acid (PABA). Microorganisms that require exogenous folic acid and do not synthesize folic acid are not susceptible to the action of sulfonamides.

Linezolid (Zyvox)

A synthetic antibiotic of the oxazolidinone class, which prevents the formation of functional 70S initiation complex. This is essential for the bacterial protein translation process. Although it seems to be bacteriostatic against Nocardia (as it is with most bacteria except pneumococci), it does seem to be a very effective therapy even as a monotherapy.