Most people with PBC (more than 90%) have antimitochondrial antibodies (AMAs) against pyruvate dehydrogenase complex (PDC-E2), an enzyme complex found in the mitochondria. People who are negative for AMAs are usually found to be positive when more sensitive methods of detection are used.People with PBC may also have been diagnosed with another autoimmune disease, such as a rheumatological, endocrinological, gastrointestinal, pulmonary, or dermatological condition, suggesting shared genetic and immune abnormalities. Common associations include Sjögrens syndrome, systemic sclerosis, rheumatoid arthritis, lupus, hypothyroidism, and coeliac disease.A genetic predisposition to disease has been thought to be important for some time. Evidence for this includes cases of PBC in family members, identical twins both having the condition (concordance), and clustering of PBC with other autoimmune diseases. In 2009, a Canadian-led group of investigators reported in the New England Journal of Medicine results from the first PBC genome-wide association study. This research revealed parts of the IL12 signaling cascade, particularly IL12A and IL12RB2 polymorphisms, to be important in the aetiology of the disease in addition to the HLA region. In 2012, two independent PBC association studies increased the total number of genomic regions associated to 26, implicating many genes involved in cytokine regulation such as TYK2, SH2B3 and TNFSF11.A study of over 2,000 patients identified a gene, POGLUT1, that appeared to be associated with this condition. Earlier studies have also suggested that this gene may be involved. The implicated protein is an endoplasmic reticulum O-glucosyltransferase.
Studies of this formulation have been published.E2/P4 with 5 mg E2 and 150 to 300 mg P4 encapsulated in microspheres in an aqueous suspension has been studied as a once-a-month combined injectable contraceptive but has not been further developed or introduced for medical use. E2/P4 with 5 mg E2 and 100 mg P4 in a macrocrystalline aqueous suspension has also been studied as a once-a-month combined injectable contraceptive, but likewise was not further developed.As of April 2022, a vaginal ring containing E2/P4 (developmental code names DARE-HRT1 and JNP-0201) is under development for use in menopausal hormone therapy. References
External links
"Estradiol mixture with progesterone". Drug Information Portal. U.S. National Library of Medicine.