Clinical Images
Unknown Gram-negative Bacilli Infection

Sunayana V. Reddy, MD; Michelle Kerk, MD; Claudine J.M. Aguilera, MD
61-year male patient with past medical history of gastro-esophageal reflux disease, alcohol dependence, remote splenectomy secondary to trauma and recent cholecystectomy due to gallstones presented to the emergency department with nausea, vomiting, diarrhea and abdominal pain for last 4 days. His initial vital signs were temperature of 98.30 Fahrenheit, blood pressure of 102/68 mmHg, heart rate of 121 beats/minute and within a few hours of presentation his physical exam became notable for altered level of consciousness, blood pressure of 85/56 mmHg and temperature of 106 0 Fahrenheit. He was then intubated, had a central line placed and was admitted to the intensive care unit. His initial blood test results indicated a white cell count of 4300 K/uL, hemoglobin of 14 g/dL, and platelet count of 29 K/uL. His chemistry results were normal except for his creatinine, which was 1.65mg/dL. He was started on vancomycin and meropenem. Initial arterial blood gas was pH of 7.11, Pco2 of 52, Po2 of 121 and bicarbonate of 13. Prothrombin time was 14.4 seconds, fibrinogen was 676 mg/dL, D –dimer was >1050 ng/mL and INR was 1.3, and lactic acid was 3.5mmol/L. His blood smear did not show schistocytes. Early goal directed therapy protocol for septic shock was initiated. Initially, he required 2 pressors: Norepinephrine and dobutamine. On hospital day two, his white count was 18,000 K/uL with bandemia of 22% and platelets of 10 K/uL. His cortisol level was normal. Computed tomography (CT) of the abdomen was suggestive of bowel wall thickening. He was started on metronidazole for possible clostridium difficile colitis.
On the evening of hospital day 2 his platelet counts decreased to 5 K/uL and he received platelet transfusions, which improved the platelet count to 35 K/uL. His blood culture on day three was positive for gram-negative rods in one bottle. On day four, the infectious disease team recommended the discontinuation of vancomycin and metronidazole.
Patient was extubated on hospital day six. His blood cultures were positive for fastidious organism. Subsequent questioning revealed that the patient had been bitten by a dog one week prior to admission. He clinically improved and was discharged on metronidazole and ciprofloxacin.
MCQ
A person who underwent splenectomy in the past following trauma experiences the sudden onset of high fever, rigors, and hypotension. By the time he reaches the hospital he has multiple petechiae and purpura over his face, arms, and legs. Acute renal failure and disseminated intravascular coagulation are demonstrated. He gives a history of frequent bites and scratches from a new pet dog.
Answer