Sarapnc. The story you tell is difficult to tease out (sorry). An elevated white blood cell count frequently is a sign of infection, but not always. First of all, it would be important to know how elevated the white blood cell count is, and what the breakdown of the cells is (I.e. are they mainly lymphocytes, neutrophils, basophils, or eosinophils). Second, it would help to know if this is a long-term issue, or more acute (recent). Third, there would be a whole lot of questions that an infectious doctor would ask, which I can’t go into depth here, but would include symptoms (fevers, chills, sweats, rash, etc.), medical history, family history, social history (including pets, immunizations, travel history) and allergies. A physical exam would follow, as would a series of blood tests. Cancer can be difficult to “rule out”, though obvious cancer can be eliminated. As for autoimmune conditions, lupus is one of many that can cause changes in white cells. The bottom line is that without knowing a whole lot more about the person’s condition, it is impossible to even speculate on an infectious cause.