Shewanella spp. are infrequently implicated in human infections but they are
emerging pathogens with particular significance in regions with warm climates, such as
Southeast Asia. This is a case of a middle-aged diabetic and hypertensive man who presented
with worsening congestive heart failure symptoms associated with fever and a painful right
leg. His right leg had numerous scabs and was tender, warm and erythematous. He was
provisionally diagnosed with decompensated heart failure precipitated by cellulitis and
uncontrolled hypertension. His blood grew non-fermentative, oxidase-positive and motile
gram-negative bacilli which produced hydrogen sulfide on triple sugar iron agar. When cultured
on blood agar, mucoid and weakly β-haemolytic colonies were observed after 48 hours. API
20 NE named the isolate as Shewanella putrefaciens but 16S rRNA sequence analysis identified
the organism as Shewanella algae. The patient was treated with a 10-day course of ceftazidime,
which resulted in the resolution of the cellulitis.