Rare Case of the Vietnamese Time Bomb!
Samineh Madani,
Madani, M.D; Stuart Cohen, M.D.
University of California, Davis Medical Center; Sacramento, CA
Introduction
Discussion
Cavitary pneumonia entails a broad differential diagnosis including infectious
and non-infectious diseases.
Epidemiology
Melioidosis is caused by Burkholderia pseudomallei, a facultative intracellular, gram
negative bacterium. Endemic in northern Australia and southeast Asia: Thailand,
Malaysia, Vietnam, Singapore, Indonesia, and Myanmar5-7. 0 to 5 cases reported in the
U.S. Mode of acquisition by ingestion, inhalation, or percutaneous inoculation of
contaminated water and soil1.
Melioidosis is a serious disease caused by Burkholderia pseudomallei.
Often called “The Great Mimicker,” melioidosis presents with an array of
clinical signs and symptoms ranging from skin lesions to cavitary pneumonia.
Pathogenesis
Melioidosis associated with septic shock results in a high mortality rate,
underlying the importance of early identification and prevention of disease.
The Burkholderia genus includes 40+ species, with B. pseudomallei, B. mallei, and B.
cepacia being the most pathogenic species. Similar to M. tuberculosis, melioidosis can
remain latent and reactivate; hence, the term “Vietnamese time bomb” attributed to
Vietnam war veterans with reactivation melioidosis.
Case Presentation
History of Present Illness
Clinical Signs and Symptoms
A 73 y/o Vietnamese gentleman presented with a two week history of fever,
left-sided pleuritic chest pain, and a non-productive cough. Patient resided in
Vietnam, working in rice fields in a village near Saigon, for two years. The
patient had previously resided in South Carolina for 18 years prior to retiring to
Vietnam.
The most common presentation is pulmonary melioidosis with fevers, chills, night
sweats, rigors, myalgias, chest pain, cough with / without sputum, and cavitary lesions on
CXR3. Bacteremic melioidosis has a poor prognosis, 36.7-53% mortality 2,4. In the
setting of pneumonia, bacteremic melioidosis has a mortality rate of 67.3-72% 2,4. With
risk factors, bacteremic melioidosis usually results in septic shock.
Diagnosis
Physical Exam
Main method of diagnosis is culture. Gram stain may show characteristic bipolar “safety
pin” staining, gram-negative bacilli. CXR may reveal consolidation, necrotizing cavitary
lesions, or pleural effusion. CT and MRI may detect spleen, liver, kidney, and prostate
abscesses.
Vital signs stable, afebrile. Thin, male with palpable axillary and
supraclavicular lymphadenopathy bilaterally. Lung exam with decreased
breath sounds in all lung fields. Benign heart and abdominal exam. No skin
ulcers, abscesses, or lesions.
Labs
Treatment
Imaging
Intravenous therapy for 2 weeks with ceftazidime, meropenem, or imipenem followed by
oral eradication therapy with TMP-SMX, folic acid, and doxycycline for 3 to 6 months.
Conclusions
1. Although rare in the United States, melioidosis has become of increased
significance due to cases seen in travelers and immigrants of endemic regions.
2. Melioidosis has a wide array of clinical manifestations ranging from localized
skin lesions, to pulmonary cavitary pneumonia, to bacteremia with septic shock.
Imaging
3. Melioidosis with bacteremia and pneumonia is associated with a high mortality
rate.
4. Early recognition and detection of melioidosis is key in correct diagnosis and
treatment in preventing mortality.
Hospital course
References
Top row from left: CXR (LUL cavitary lesion; CT chest (LUL cavitary lesion)
Bottom row: CT chest (LAD); CT abdomen (hepatic lesion); CT abdomen (splenomegaly)
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