How immunocompromised are short bowel patients receiving home parenteral nutrition? Apropos a case of disseminated Fusarium oxysporum sepsis.

BACKGROUND: Catheter-related sepsis is the most frequent complication in patients receiving home parenteral nutrition (HPN) for short bowel syndrome (SBS). A low-grade systemic inflammatory state and an altered mucosal immune response, as well as diminished intestinal barrier function have been characterized in these patients. The possibility of systemic immunocompromise has only recently been suggested.

CASE DESCRIPTION: A 45-year-old female with traumatic SBS was admitted for possible catheter-related sepsis. She was asplenic and had insulin-dependent diabetes mellitus as a result of a pancreatic resection. A large skin ulceration was present on her left calf, which appeared unusual for a disseminated bacterial infection. Chest x-ray and computed tomography scan revealed multiple subpleural pulmonary infiltrates consistent with bacterial or fungal dissemination. Blood cultures from the port system and from the peripheral blood grew Staphylococcus haemolyticus and Fusarium oxysporum. The port system was removed, and flucloxacillin and voriconazole were given for 33 and 35 days, respectively. Clinical signs of disseminated sepsis resolved slowly. Bone marrow biopsy ruled out primary hematologic disease.

CONCLUSIONS: (1) Catheter-related sepsis in patients on HPN is usually caused by Gram-positive or Gram-negative bacteria or by Candida species. Identification of molds in blood cultures strongly suggests Fusarium species, which should be treated appropriately with voriconazole or amphotericin B. (2) HPN and SBS aggravated by asplenism and diabetes mellitus can cause severe immunocompromise. (3) Fusaria have a strong tendency to persist or reappear after bone marrow transplantation, which is therefore relatively contraindicated in these patients.