EXPERT ANALYSIS FROM WCD 2015
VANCOUVER (FRONTLINE MEDICAL NEWS) – Two serious emerging skin and soft tissue infections whose progress physicians will want to chart are melioidosis and Acinetobacter baumannii infection , Dr. Dirk M. Elston advised at the World Congress of Dermatology.
Both Burkholderia pseudomallei – the cause of melioidosis – and Acinetobacter baumannii are gram-negative organisms that laboratory staff sometimes mistakenly dismiss as culture contaminants. But melioidosis has a case fatality rate of up to 40%, and A. baumannii is an increasingly multidrug-resistant cause of community-acquired cellulitis, according to Dr. Elston, chair of the department of dermatology and dermatologic surgery at the Medical University of South Carolina, Charleston.
Dr. Elston, also managing director of the Ackerman Academy of Dermatopathology in New York, offered his views on these two emerging infections.
Melioidosis
“We know melioidosis from the rice paddies of Vietnam as a plaguelike ulceroglandular syndrome. It has reemerged in the Caribbean,” Dr. Elston reported.
Indeed, investigators at the Centers for Disease Control and Prevention reported earlier this year that melioidosis is now endemic in Puerto Rico based upon its findings of high seropositivity rates among patient contacts plus isolation of the causative organism from soil samples ( Clin Infect Dis. 2015 Jan 15;60(2):243-250 ). The infection, which is believed to be underdiagnosed, also has been reported at numerous other sites in the Caribbean basin and in Latin America and Africa, as well as in Southeast Asia.
Although skin and soft tissue abscesses are common manifestations of this acute febrile illness, the most common clinical presentation of melioidosis is acute pneumonia with or without septicemia, which can be fulminant.
According to the CDC investigators, up to 80% of patients with melioidosis have diabetes, chronic lung disease, and/or excessive alcohol use as risk factors for the infection. In the Puerto Rican study, a history of injection drug use was for the first time identified as another risk factor. When in endemic areas such as Puerto Rico, individuals with diabetes or other risk factors should protect themselves from direct exposure to soil and water to reduce their risk of what is believed to be a transcutaneously acquired infection. The investigators advised that individuals with skin wounds or sores do the same.
The recommended treatment for melioidosis is intravenous ceftazidime, imipenem, or meropenem ( N Engl J Med. 2012 Sep 13;367(11):1035-1044 ).
A. baumannii infection
In a recent report, Dr. Adam J. Friedman and his colleagues at the Albert Einstein College of Medicine in New York said that A. baumannii’s pattern of evolution to date is strikingly similar to that of methicillin-resistant Staphylococcus aureus. A. baumannii has displayed increasing pathogenicity and antibiotic resistance. The investigators warned that there is a real danger that, like MRSA, extensively drug-resistant A. baumannii will become a common community-acquired infection arising in previously healthy patients ( JAMA Dermatol. 2014 Aug;150(8):905-906 ).
“There are some strains of gonococcus and some strains of Acinetobacter baumannii that appear to be resistant to all known antibiotics,” Dr. Elston said.
He reported having no relevant financial conflicts of interest.
