"A diagnosis of fibromyalgia is valid irrespective of other diagnoses. A diagnosis of fibromyalgia does not exclude the presence of other clinically important illnesses." American Pain Society 2019
In 2019, the American Pain Society in collaboration with the U.S. Food and Drug Administration developed a new diagnostic system using two dimensions. The first dimension included core diagnostic criteria and the second included common features. In accordance to the 2016 diagnosis guidelines, the presence of another medical condition or pain disorder does not rule out the diagnosis of fibromyalgia. Nonetheless, other conditions should be ruled out as the main explaining reason for the patients symptoms. The core diagnostic criteria are:
Multisite pain defined as six or more pain sites from a total of nine possible sites, for at least three months
Moderate to severe sleep problems or fatigue, for at least three monthsCommon features found in fibromyalgia patients can assist the diagnosis process. These are tenderness (sensitivity to light pressure), dyscognition (difficulty to think), musculoskeletal stiffness, and environmental sensitivity or hypervigilance. Self-report questionnaires
Some research has suggested using a multidimensional approach taking into consideration somatic symptoms, psychological factors, psychosocial stressors and subjective belief regarding fibromyalgia. These symptoms can be assessed by several self-report questionnaires. Widespread Pain Index (WPI)
The Widespread Pain Index (WPI) measures the number of painful body regions. Symptom Severity Scale (SSS)
The Symptom Severity Scale (SSS) assesses the severity of the fibromyalgia symptoms. Fibromyalgia Impact Questionnaire (FIQ)
The Fibromyalgia Impact Questionnaire (FIQ) and the Revised Fibromyalgia Impact Questionnaire (FIQR) assess three domains: function, overall impact and symptoms.
Patients with rheumatoid arthritis (RA) have been found to make autoantibodies toward the carbamylated form of A1AT in the synovial fluid. This suggests that A1AT may play an anti-inflammatory or tissue-protecting role outside the lungs. These antibodies are associated with a more severe disease course, can be observed years before disease onset, and may predict the development of RA in arthralgia patients. Consequently, carbamylated A1AT is currently being developed as an antigenic biomarker for RA. Nomenclature
The protein was initially named "antitrypsin" because of its ability to bind and irreversibly inactivate the enzyme trypsin in vitro covalently. Trypsin, a type of peptidase, is a digestive enzyme active in the duodenum and elsewhere. The term alpha-1 refers to the proteins behavior on protein electrophoresis. On electrophoresis, the protein component of the blood is separated by electric current. There are several clusters, the first being albumin, the second being the alpha, the third beta and the fourth gamma (immunoglobulins). The non-albumin proteins are referred to as globulins. The alpha region can be further divided into two sub-regions, termed "1" and "2". Alpha-1 antitrypsin is the main protein of the alpha-globulin 1 region. Another name used is alpha-1 proteinase inhibitor (α1-PI). Genetics
The gene is located on the long arm of chromosome 14 (14q32.1). Over 100 different variants of α1-antitrypsin have been described in various populations. North-Western Europeans are most at risk for carrying one of the most common mutant forms of A1AT, the Z mutation (Glu342Lys on M1A, rs28929474).