Emerging pathogens: A case of Wohlfahrtiimonas chitiniclastica and Ignatzschineria indica bacteremia

Abstract

<i>Wohlfahrtiimonas chitiniclastica</i> and <i>Ignatzschineria indica</i> are rare causes of infection in humans and have been linked to infestation with fly larvae in open wounds. Both organisms are emerging causes of disease globally and co-infection resulting in bacteremia is rare. An 82-year-old male with bilateral lower extremity infections was hospitalized due to fall with associated right lower extremity pain. On exam, a maggot infested ulcer was identified on his right lower extremity. On day three of hospitalization, blood cultures grew gram-negative and gram-variable rods, and methicillin-resistant <i>Staphylococcus aureus</i>. Further analysis of the gram negative and gram variable rods revealed <i>W. chitiniclastica</i> and <i>I. indica</i> respectively. Both <i>I. indica</i> and <i>W. chitiniclastica</i> were pan sensitive to all antimicrobials tested with the exception of tetracyclines to which <i>W. chitiniclastica</i> was fully resistant and <i>I. indica</i> was intermediately sensitive. The patient was treated with two weeks of IV ceftriaxone and was discharged with plans to complete a six-week course of IV daptomycin due to MRSA bacteremia. All repeat blood cultures were negative. Until recently <i>W. chitiniclastica</i> and <i>I. indica</i> infections have been documented only in farm and feral animals. Major risk factors for infection include: poor hygiene, open wounds, peripheral vascular disease, and myiasis. Due to the rarity of infection, identification of both organisms can be difficult, therefore a high index of suspicion is required.