Chapter 18: Sepsis
A 40-year-old man with chronic lymphocytic leukemia was admitted for small bowel obstruction. He had an exploratory laparotomy and lysis of adhesions. Postop day 4, he is found nauseous and vomiting. He is awake and following commands. Vital signs are as follows: BP of 130/70 mmHg, HR of 70 beats/min, RR of 18 breaths/min; O2 sat of 99% on 2 Liters via nasal cannula (NC), temp of 97.1°F. On auscultation, he is noted to have rhonchi at the right base. His labs are obtained 6 hours later and include the following:
|WBC ||14 × 103/μL |
|Hemoglobin ||10 g/dL |
|Platelets ||100 × 103/μL |
|Sodium ||135 mEq/L |
|Potassium ||4 mEq/L |
|Chloride ||108 mEq/L |
|Blood urea nitrogen ||20 mg/dL |
|Creatinine ||2 mg/dL |
|Glucose ||100 mg/dL |
|Procalcitonin ||0.20 mEq/L |
On the chest radiograph, he is noted to have right lower lobe infiltrate. What is the next step?
A. Start piperacillin-tazobactam and vancomycin
B. Start ceftriaxone and azithromycin
Procalcitonin is a biomarker that has helped with antibiotic stewardship. It is normally secreted from the thyroid gland and lungs and is a precursor to calcitonin. In the setting of bacterial infection, it is also secreted from the spleen, kidneys, liver, adrenal glands, brain, spine, pancreas, stomach, small intestine, colon, heart, muscle, skin, fat, and testes. It is more specific than leukocytosis or CRP for bacterial infection and rises within 3 to 6 hours, peaks at 6 to 12 hours, and has a half-life of 24 hours. It is not affected by immunosuppression. In the setting of massive surgery, trauma, or burns, the initial levels would be falsely elevated, but subsequently, levels will trend down if there is no infection. If there is a concomitant infection, the levels will remain elevated. For initial evaluation of bacterial infection, with a PCT of less than 0.1 ng/L or a PCT of 0.1 to 0.25 ng/L, antibiotics are discouraged, (choice C). However, antibiotics are still considered with these levels if (1) PCT is less than 0.1 ng/L with CAP with PSI class V, CURB-65 greater than 3, and/or COPD with Global Initiative for Obstructive Lung Disease (GOLD) IV; or (2) PCT less than 0.25 µg/L with CAP with PSI class IV or V, CURB-65 greater than 2, and COPD with GOLD III or IV., If the PCT is between 0.25 and 0.5 ng/L or greater than 0.5 ng/L, antibiotics are encouraged., If antibiotics are initiated, repeat PCT on day 3, 5, and 7 and stop if (1) PCT is 0.1 to 0.25 ng/L or (2) peak PCT is high but ...