Infectious complications are common adverse events of solid organ transplantation and immunosuppressive therapy. In the perioperative setting, most infections are of bacterial or viral origin. Risk assessment of donor and recipient focuses mostly on blood-borne pathogens. Occasionally, parasitic infections are reported after transplantation. In regard to the latter, we report the case of a 57-year-old patient who underwent simultaneous pancreas-kidney transplantation and shortly thereafter developed diarrhea, abdominal bloating and weight loss due to Giardia duodenalis.