Melioidosis in a Returning Traveler

Disscussion

Kathleen Volkman, MD; Kerry Colby, MD; Sylvia LaCourse, MD; Andrew White, MD DEPARTMENT OF INTERNAL MEDICINE, UNIVERSITY OF WASHINGTON

References1. Wiersinga, W. Joost. et.al. Melioidosis. N ENGL J

MED 367;11. 9/13/2012.2. Peacock SJ, Schweizer HP, Dance DAB, Smith

TL, Gee JE, Wuthiekunan V, et al. Management of accidental laboratory exposure to Burkholderia pseudomallei and B. mallei. Emerg Infect Dis. 2008 July http://wwwnc.cdc.gov/eid/article/14/7/07-1501.htm

Introduction

Case ReportA 65 year old man developed acute chest pain while hiking near a waterfall in Thailand. He was treated for a STEMI with placement of a drug eluting stent. Upon returning to the US one week later, he developed inspiratory chest pain, dyspnea, and fever. Evaluation revealed a leukocytosis, left lower lobe consolidation, and a small pleural effusion consistent with pneumonia. Echocardiography also found a new left ventricular thrombus. He was treated with moxifloxacin and warfarin, but the pleuritic pain and effusion persisted after one week. He was then given amoxicillin-clavulinic acid and clindamycin. Thoracentesis was deferred due to anticoagulation and subsequent clinical improvement. However, after three weeks, he returned with dysuria, increased urinary frequency and nocturia. Urine cultures grew Burkholderia pseudomallei, which was confirmed by sequencing analysis. This prompted inpatient care for disseminated Burkholderia infection (melioidosis). CT demonstrated multiple pulmonary nodules, a persistent left pleural effusion, and a rim-enhacing hypodensity in the prostate consistent with abscess. Blood and thoracentesis cultures had no growth. He was treated with ceftazidime 2gm IV Q6hrs  for 2 weeks, followed by 6 months of high-dose oral trimethoprim-sulfamethoxazole.

Treatment requires prolonged, tailored antibiotic therapy based on susceptibilities. Notably, B. pseudomallei is known to be resistant to penicillin, ampicillin, and first and second generation cephalosporins. Most patients have one or more risk factors, including diabetes, alcohol use, chronic kidney disease, or cancer. About 80% of adults in endemic regions are found to have underlying diseases 2. This patient requires age-appropriate cancer screening and follow up imaging of lung and prostate findings. B. pseudomallei is not typically transmitted person-to-person , but is classified by the CDC as a category B bioterrorism agent that requires special laboratory precautions. 

Melioidosis is a potentially life-threatening disseminated infection caused by Burkholderia pseudomallei, a soil-dwelling gram-negative bacillus found in SE Asia and Austrailia1. Mortality rates can reach 40% in northeast Thailand and up to 14% in Australia. Roughly half of patients with B. pseudomallei present with pneumonia. Genitourinary infections, abscess and bacteremia are also common.Transmission is primarily via percutaneous inoculation, however inhalation can occur especially in the setting of severe weather (i.e heavy rainfall, tsunamis, etc.).

Figure 1 - Patient’s prostatic abscess on hospital admission

Figure 2 – Patient’s pleural effusion on admission