口腔病理科 On-Line KMU Student Bulletin
- 1 -
原文題目(出處)： Melioidosis: an uncommon cause of neck abscess
原文作者姓名： Abu Bakar Zulkiflee, Narayanan Prepageran, Rajan Philip 通訊作者學校： Department of Otolaryngology, University Malaya Medical
Center, University Malaya, Kuala Lumpur 報告者姓名(組別)： 沈明萱
報告日期： 97.9.23
內文：
Introduction
Melioidosis is a life-threatening disease caused by Burkholderia pseudomallei. It is endemic in Southeast Asia with a few reports from the Western world. It is transmitted via inhalation, ingestion or direct contact with an open wound. Clinically it may present with local or systemic symptoms.
Mortality rate is very high in systemic disease; but local infection is usually mild, which causes delay in seeking medical attention.
Case
A 47-year-old housewife with type 2 diabetes mellitus presented with a mass on the right side of the neck for 2 weeks. She denied any pain，fever or difficulty in swallowing。She had no breathing problems or dental complaints.
Examination
¾ Apyretic
¾ A mass on right posterior triangle of the neck for 2 weeks, nontender.
Systemic examination
¾ Normal
¾ Total white count；mildy eleveated
¾ Serum glucose level；normal Treatment
She underwent emergency surgical drainage under general anesthesia. Pus for culture and sensitivity grew Burkholderia pseudomallei.
During ward stay and postoperative daily neck dressings，she was on a 6-week course of intravenous ceftazidime 1g（第三代cephalosporin） twice a day, combined with co- trimoxazole（trimethoprim 和 sulfamethoxazole 以 1:5 組 合 ）. Postoperative period was uneventful，and she was discharge well with oral co- amoxyclav（ Amoxicillin Sodium 和Clavulanic Acid.）
¾ Clinical Photo
¾ Abscess in the right posterior triangle of the neck
口腔病理科 On-Line KMU Student Bulletin
- 2 -
CT scan
¾ Computed tomographic scan of the neck with hypodens lesion at the right posterior triangle of the neck
Discussion
¾ Cause: Burkholderia pseudomallei (Pseudomonas pseudomallei)
¾ Free-living, G(-),aerobic
¾ Widespread in Southeast Asia, Northern Australia
¾ Usually affects farmers or those from rural areas in the endemic area
¾ Natural inhabitant of soil and water in the tropics and subtropics but also survive in dry atmospheric condition.
¾ Zoonotic；spread to human from animals through inoculation、ingestion or inhalation. Cases of human-to-human spread are rare but documented.
Clinical manifestation
Range from localized infection to acute pneumonia and fulminant septic melioidosis. Once infected, it may remain dormant and become active after months、
years or decades when the host is immunocompromised.
Localized melioidosis occurs in the form of acute suppurative lesions or superficial and deep-seated abscess in the psoas muscle, parotid glands, cervical lymph nodes, and at the root of the mesentery. It may also present
as cellulitis, chronic otitis media, and sepsis after burns and trauma.
In this case, prolonged painless neck swelling not associated with fever makes melioidosis one of the differential diagnoses. Its clinical presentation differs from other typical “hot” abscesses, which are commonly caused by oral organisms.
Treatment
¾ Goal；Reduce mortality and morbidity
¾ Systemic melioidosis；ceftazidime（第三代cephalosporin），carbapenem（Beta-lactam antibiotic）
¾ Localized infection；Doxycycline（tetracycline衍生物） in combination with co-
口腔病理科 On-Line KMU Student Bulletin
- 3 -
trimoxazole（trimethoprim和sulfamethoxazole以1:5組合）
¾ Acute severe melioidosis
Ceftazidime alone or combine with co- trimoxazole or ciprofloxacin（
synthetic antibiotic，inhibiting cell division）
Parental amoxyclav（ Amoxicillin Sodium和Clavulanic Acid.）
Imipenem（intravenous β-lactam antibiotic）
Meropenem subgroup of carbap（1g or 25mg/kg every 8 hours IV for 14 days）
¾ Despite appropriate treatment, melioidosis has a high relapse rate
¾ Average time between discharge from hospital and relapse is 21 weeks
¾ Treated patients require long-term follow-up because B. pseudomallei remains latent for up to 26 years in the body
¾ For eradication therapy, co-amoxyclav（ Amoxicillin Sodium和Clavulanic Acid.） is a safe and well-tolerated antimicrobial agent.
Conclusion
Melioidosis should be borne in mind in cases of cold
abscesses of the neck when the characteristic features of abscess are missing, for example, fever and tenderness.
Ceftazidime is recommended while waiting for the definitive
result and must be subsequently continued with eradication therapy if the culture is positive.
題號 題目
