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, but seronegativity does not exclude a diagnosis of melioidosis, and culture is still the criterion standard for diagnosis.
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. Ceftazidime resistance in B pseudomallei is rare, and resistance to carbapenems has not been described.
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.
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. 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. 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). Amoxicillin/clavulanate is also an option for adults unable to tolerate trimethoprim/sulfamethoxazole or doxycycline.
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. 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.
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.