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Sweet's syndrome: a reaction to non-tuberculous mycobacterial infections

Chanisada Tuchinda1, Siripen Puavilai, Boonmee Sathapatayavongs

  • 1Department of Medicine, Faculty of Medicine, Ramathibodi Hospital Medical School, Mahidol University, Bangkok, Thailand.

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Hypersensitivity Reactions: Immune-Complex Reactions

Type III hypersensitivity reactions occur when antigen–antibody complexes form and activate the complement system. Normally, these complexes help the clearance of antigens by phagocytes and red blood cells. However, when large numbers of immune complexes are present, they can deposit in tissues—particularly in the walls of blood vessels—leading to inflammation and tissue injury. These deposits trigger complement activation and neutrophil recruitment, resulting in serum sickness, a systemic...
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Pulmonary Tuberculosis III

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The first classification is based on the development of the disease, and it includes the following categories:
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Drug Toxicity: Allergic Reactions

Drug-related allergies are immune-mediated responses triggered by the administration of pharmacological agents. These hypersensitivity reactions are classified based on the immune mechanisms involved. The four primary types—Type I, II, III, and IV—are mediated by different immunological pathways and exhibit distinct clinical manifestations.Type I Hypersensitivity/ IgE-Mediated Reactions: Immunoglobulin E (IgE) immediately mediates Type I hypersensitivity reactions. Upon initial exposure to a...
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Myocarditis I: Introduction

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Pulmonary Tuberculosis II

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