The organism is intrinsically resistant to a wide range of antimicrobials (eg, ampicillin, ceftriaxone, metronidazole, moxifloxacin, clindamycin), and identification by culture often takes a minimum of 48 hours. A high level of clinical suspicion is required if appropriate therapy is to be initiated in a timely fashion. Although serologic methods are available for the diagnosis of melioidosis, they are of limited value in endemic areas; these methods are more useful for the diagnosis of melioidosis in visitors from nonendemic areas,[17] but seronegativity does not exclude a diagnosis of melioidosis, and culture is still the criterion standard for diagnosis.[16]
The treatment of choice is parenteral ceftazidime (120 mg/kg/day in three divided doses; maximum dose, 2 g three times daily). Meropenem and imipenem are alternative treatments.[9] Ceftazidime resistance in B pseudomallei is rare, and resistance to carbapenems has not been described.[9]
The recommended minimum duration of parenteral treatment is 10 days, and it should be continued until the patient's clinical findings return to baseline. Usually, patients have a slow clinical response to treatment. The median time to fever clearance is 9 days, despite adequate therapy.[9]
Unlike in most other bacterial diseases, failure to respond after 48 hours of appropriate treatment is not an indication to revise antibiotic therapy or consider alternative diagnoses.[1,9] Although resistance can develop during the course of treatment, this is uncommon.[9] However, obtaining repeat cultures from any patient who fails to defervesce after 7 days of therapy is prudent.
Adequate supportive treatment is essential and includes fluid resuscitation, artificial ventilation, tight glycemic control, and renal replacement therapy. Adjunctive treatment with granulocyte colony-stimulating factor is ineffective.[18] The efficacy of adjunctive low-dose steroids or activated protein C (drotrecogin alfa) in melioidosis is unknown.
Relapse and reinfection are common; therefore, patients require 20 weeks of oral eradication therapy after completing parenteral treatment. Potential choices for adults include trimethoprim/sulfamethoxazole (16/80 mg/kg/day in two divided doses; maximum dose, 320/1600 mg twice daily) and doxycycline (4 mg/kg/day in two divided doses; maximum dose, 100 mg twice daily).[2,9] Children younger than 8 years and pregnant women (for whom doxycycline is relatively contraindicated) should be given amoxicillin/clavulanate (180/45 mg/kg/day in three divided doses).[19] Amoxicillin/clavulanate is also an option for adults unable to tolerate trimethoprim/sulfamethoxazole or doxycycline.[19]
Thirteen percent of patients have relapse or reinfection in the 10 years after their primary infection; for this reason, patients with B pseudomallei in Thailand require long-term follow-up.[20] Patients who have no systemic symptoms and only a single localized abscess that has been completely drained may be treated with oral eradication therapy alone.[9]
In this case, a nasogastric aspirate obtained on admission returned culture-positive for B pseudomallei. The patient was continued on intravenous ceftazidime. He had spiking fevers of up to 102.2°F until hospital day 5, at which time he defervesced. He was treated with intravenous ceftazidime for 21 days during the hospitalization. The patient made a good recovery and was discharged home on oral amoxicillin/clavulanate for a 5-month follow-up course. He was doing well when seen at follow-up 1 month later.
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Cite this: Gavin Christian K.W. Koh, Richard J. Maude, Pramot Srisamang. A 3-Year-Old Boy With Fever and Drowsiness - Medscape - Jul 28, 2017.
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