Organ transplant rejection is a complex immunological response wherein the recipient’s immune system identifies the transplanted organ as foreign and mounts an attack against it. Despite advancements in surgical techniques and immunosuppressive therapy, rejection remains a significant challenge to transplant success and long-term graft survival. Understanding the types, underlying mechanisms, early detection, and strategies for
Behçet’s disease is a rare, chronic, multisystemic inflammatory disorder characterized by recurrent oral ulcers, genital lesions, ocular inflammation, and systemic involvement. One of the earliest and most consistent features of Behçet’s disease is the presence of recurrent oral aphthous ulcers, which often serve as the initial clinical manifestation. These ulcers are not merely superficial irritations
Oral lichen planus (OLP) is a chronic, autoimmune-mediated inflammatory condition that affects the mucous membranes of the mouth. Characterized by bilateral, white, lace-like lesions and, in some cases, painful erosions, OLP poses both clinical and diagnostic challenges. Although its precise etiology remains unclear, it is believed to involve immune dysregulation targeting basal keratinocytes of the
Oral candidiasis, commonly referred to as oral thrush, is a fungal infection in the oral cavity caused predominantly by Candida albicans. It manifests as white, creamy patches on the tongue, inner cheeks, palate, and throat. While often benign, the infection can become persistent or invasive in immunocompromised individuals or those with underlying health conditions. Timely
Optic neuritis is an inflammatory condition affecting the optic nerve, the structure responsible for transmitting visual information from the eye to the brain. This condition often leads to sudden vision loss, eye pain, and color vision abnormalities. It is most commonly associated with multiple sclerosis (MS) but can also occur independently or in connection with
Opisthorchiasis is a significant parasitic infection caused by trematodes, primarily Opisthorchis viverrini and Opisthorchis felineus. These liver flukes inhabit the bile ducts of humans and can cause severe hepatobiliary diseases, including cholangitis, cholecystitis, gallstones, and cholangiocarcinoma. Endemic in parts of Southeast Asia and Eastern Europe, opisthorchiasis poses a major public health challenge due to its
Opioid-induced respiratory depression (OIRD) is a life-threatening condition characterized by a reduced drive to breathe due to the pharmacologic effects of opioid medications on the central nervous system. As opioid use continues across clinical and non-clinical settings, the risk and prevalence of OIRD remain a significant public health concern. The Pharmacodynamics of Opioids in Respiratory
Opioid-induced constipation (OIC) is one of the most prevalent and distressing adverse effects of opioid therapy. Unlike other opioid side effects such as sedation or nausea that may diminish with time, OIC tends to persist throughout treatment and often worsens. It significantly affects patients’ quality of life, treatment adherence, and clinical outcomes, particularly in individuals
Opioid withdrawal is a clinical syndrome that occurs when a person who is physically dependent on opioids abruptly reduces or stops usage. It is the result of the body’s adaptation to prolonged opioid exposure and manifests through a constellation of physical and psychological symptoms. Although rarely life-threatening, opioid withdrawal can be intensely uncomfortable and often
Opioid Use Disorder (OUD) is a chronic, relapsing medical condition characterized by the compulsive use of opioids despite harmful consequences. It involves both physical dependence and behavioral addiction. The disorder spans across the misuse of prescription opioids such as oxycodone, morphine, and hydrocodone, as well as illicit substances like heroin and synthetic opioids, including fentanyl.