It was proposed that the large amount of egg antigens released by S. japonicum interact with antibodies leading to the formation of high volume of immune complexes, which cause enlargement of the lymph tissues. This sequence of events can lead to clinical manifestation of fever, enlargement of spleen and liver due to fibrosis, portal hypertension, and death.Chronic Infection
The clinical manifestations of chronic infection is mainly caused by immune reaction to the eggs entrapment within tissues resulting in granuloma formation and chronic inflammation. Adult worms live together in pairs (one male and female), sexually reproduce, and lay eggs in the veins around the intestines and bladder depending on the species, and these eggs can rupture the wall of the veins to escape to the surrounding tissues. The eggs make their way through the tissues to the intestinal or bladder lumen with help of proteolytic enzymes, however, a large amount of eggs are unable to finish their journey and remained stuck within the tissues where they can elicit an immune response. The miracidia in these eggs can then release antigens that stimulate an inflammatory immune response. The miracidia within the eggs live for around 6–8 weeks before they die and stop releasing the antigens. The granulomatous response is a cellular immune response mediated by CD4+ T cells, neutrophils, eosinophils, lymphocytes, macrophages, and monocytes, and this chronic inflammatory response elicited by the eggs can cause fibrosis, tissue destruction, and granuloma nodules that disrupt the functions of the organs involved.
Lefamulin, sold under the brand name Xenleta, is an antibiotic medication used it to treat adults with community-acquired bacterial pneumonia. It is taken by mouth or by injection into a vein.Relatively common side effects include diarrhea, nausea, pain at the site of injection, and liver inflammation. It is a pleuromutilin antibiotic that inhibits the large subunit of bacterial ribosomes.Lefamulin was approved for medical use in the United States in August 2019, and in the European Union in July 2020. Medical uses
Lefamulin is used to treat adults with community-acquired bacterial pneumonia. It was also investigated for treatment of acute bacterial skin and skin-structure infections (ABSSSI). Spectrum of activity
Lefamulin has in vitro activity against Streptococcus viridans, Moraxella catarrhalis, Enterococcus faecium, methicillin-resistant Staphylococcus aureus (MRSA), among other bacteria. History
It was developed by Nabriva Therapeutics and approved in the United States in 2019. It was granted fast track status by the US Food and Drug Administration (FDA) in 2014. Although pleuromutilin antibiotics were first developed in the 1950s, lefamulin is the first to be used for systemic treatment of bacterial infections in humans. Society and culture
Legal status
Lefamulin was approved for medical use in the United States in August 2019, and in the European Union in July 2020. References
External links
"Lefamulin". Drug Information Portal. U.S. National Library of Medicine.