Two Cases of Necrotizing Fasciitis Due toAcinetobacter baumannii

Abstract

Necrotizing fasciitis has conventionally been associated with the streptococci, and when it is caused by other organisms, it is most often the result of a polymicrobial infection. We report on two cases of fatal monomicrobial necrotizing fasciitis due to Acinetobacter baumannii, an unusual finding that may be an indication of enhanced virulence of the organism. CASE REPORTS Case 1. Patient X was a 21-year-old male with multiple medical problems, including end-stage renal disease secondary to systemic lupus erythematosus, thrombotic thrombocytopenic purpura, and mesenteric vasculitis. The patient had been treated with prolonged courses of systemic corticosteroids and intermittently with rituximab and had undergone multiple courses of treatment consisting of plasmapheresis, blood transfusions, and hemodialysis. In August 2007, he was admitted to the hospital for pulmonary edema and bright red blood from the rectum. At that time, blood cultures grew vancomycinresistant Enterococcus faecium and Candida albicans. He was treated with daptomycin and fluconazole, and all blood cultures subsequently became negative. Days later, he tested positive for Clostridium difficile-associated colitis; therefore, metronidazole was added to his antibiotic regimen.Despite embolization of the vessels of the terminal ileum, the patient continued to experience gastrointestinal bleeding. He therefore underwent an exploratory laparotomy, ileocecal resection, and ileostomy 3 weeks after admission. He appeared to be recovering until 5 days later, when he developed bacteremia caused by the gram-negative organisms Klebsiella pneumoniae and Citrobacter freundii, for which he was treated with imipenem and was continued on metronidazole.Two weeks after the ileocecectomy, at approximately 2 a.m., the patient noted pain along his left flank and thigh. Physical examination revealed faint erythema and tenderness. By 11 a.m. of the same day, there were marked increases in the levels of erythema, edema, and pain. The erythema extended beyond a marked line by greater than 2 cm in 1 h. It extended from flank to flank across the patient's back and thighs bilaterally. Bullae appeared on the skin over a similar distribution. An incision was performed at the bedside, and a frozen section revealed inflamed and necrotic fibroconnective tissue and muscle, with quantitative biopsy specimens revealing Ͼ100,000 gram-negative rods. The patient gave consent for and underwent an emergent debridement in the operating room for suspected necrotizing fasciitis. Amikacin, vancomycin, and clindamycin were empirically added to his existing antibiotic regimen of imipenem and metronidazole, pending culture and susceptibility testing results.

Antimicrobial Activity of Gallium Protoporphyrin IX against Acinetobacter baumannii Strains Displaying Different Antibiotic Resistance Phenotypes

“…These findings are relevant since patients suffering from severe wound and soft tissue infections require immediate and effective antimicrobial chemotherapy. Equally concerning is the emergence of A. baumannii isolates with increased and/or altered virulence, such as the LAC-4 strain and isolates obtained from deadly cases of necrotizing fasciitis, respectively (37,38). These infections require immediate and effective antimicrobial treatment not only because of the devastating nature of these infections but also because of the alarming MDR phenotype of the bacterial agents responsible for these diseases.…”

Clinical and Pathophysiological Overview of Acinetobacter Infections: a Century of Challenges

“…These cases have typically been reported for immunocompromised patients, mostly in patients with HIV, hepatic cirrhosis, solid-organ transplant, or diabetes mellitus (216)(217)(218)(219)(220)(221). They have been either community-or hospital-onset cases and have not necessarily been the result of recognized, antecedent trauma.…”

The Opportunistic Human PathogenAcinetobacter baumanniiSenses and Responds to Light

“…More recently, it was identified as the sole causative agent of necrotizing fasciitis (11). This pathogen survives in hospital environments despite unfavorable conditions such as desiccation, nutrient starvation, and antimicrobial treatments (6,52).…”