A 73-year-old diagnosed with giant cell arteritis, requiring methylprednisolone, presented to hospital with headache. Her medical history is notable for a renal transplant on maintenance immunosuppression and insulin dependent diabetes mellitus. Her admission was complicated by a gastrointestinal bleed and pneumonia. Chest X-ray indicated bilateral bronchopneumonia. Computerised tomography of the brain detected no acute intracranial pathology. A set of blood cultures grew Escherichia coli. Despite antimicrobials and supportive care, the patient rapidly deteriorated. During the patient’s deterioration, two aerobic blood culture bottles (BacTALERT, bioMerieux, France) grew cream, nonmucoid ‘yeast-like’ colonies on sheep blood and Sabouraud 4?xtrose agar (Thermo Scientific, South Australia). Gram stain of the colony showed Gram-positive large spherical cells. The organism was identified as Prototheca wickerhamii by VITEK (bioMerieux) and MALDI-TOF (VITEK MS, bioMerieux) mass spectrometry. The patient succumbed to multi-organ failure, and a diagnosis of Prototheca blood stream infection was made posthumously.