Because the symptoms of systemic lupus erythematosus (SLE) in particular can be so varied, the diagnosis of lupus is often not easy. It is not uncommon for people affected by lupus to be treated by their primary care physician or even rheumatologist for joint symptoms for a longer period of time before a diagnosis of lupus is considered. Various parameters are taken into account in the diagnosis of lupus. A number of tools are available for making the diagnosis of lupus and assessing the course of the disease.
Lupus: diagnosis thanks to ACR criteria.
For many years, the American College of Rheumatology (ACR) has established a set of criteria to help diagnose lupus. This includes eleven criteria – both typical lupus symptoms and complaints such as skin changes and joint pain as well as laboratory findings such as blood changes (reduced number of red or white blood cells or platelets), certain autoantibodies in the blood (against DNA, ribonucleoproteins, phospholipids) and in microscopy (antinuclear antibodies = ANA).
If four of the eleven criteria are present, the diagnosis of SLE is considered likely (80-90 percent).
Diagnosis of lupus based on SLE indices.
In addition to the widely used ACR catalog, several other lists of criteria exist that can be used to make a diagnosis and assess the disease for severity. This, in turn, is necessary to optimize lupus therapy. These indices also evaluate complaints, examination findings and laboratory values, sometimes even separately by organ system.
All have advantages and disadvantages. For example, some do not consider worsening of pre-existing symptoms, others do not consider subjective complaints such as fatigue, and still others do not distinguish between mild symptoms and organ changes. Some are more appropriate than others for assessing disease in children.
Here are the most important lupus indices:
- Systemic lupus activity measure (SLAM): scale with three levels of severity.
- British siles Lupus assessment group (BILAG): scale with four severity levels.
- Systemic lupus erythematosus disease activity index (SLEDAI).
- SLE damage index
- European Consensus Lupus Activity Measurement (ECLAN).
