Healthcare Purchasing News Magazine -- Sepsis can be tricky to diagnose. It is not clear cut, because the symptoms can be attributed to other causes. Diagnosis of sepsis is not based only on an infection but on several symptoms. Some people are more susceptible to sepsis: the very young, the very old, those with chronic illnesses, and the immunocompromised. Severe sepsis can lead to organ dysfunction such as difficulty breathing, low or no urine output, abnormal liver tests, and changes in mental status. Septic shock is the most serious level of sepsis and is diagnosed when blood pressure drops dangerously.