Post Type Archives: Topics

Salivary gland tumors are rare tumors that begin in the salivary glands. Salivary gland tumors can begin in any of the salivary gland, but parotid gland is most common site. Following are the most common forms- Pleomorphic Adenoma Pleomorphic adenomas are benign tumors consisting of mixture of epithelial and mesenchymal cells. Epithelial elements are dispersed […]

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by recurrent abdominal pain and altered bowel habit in the absence of significant organic pathology. Pathogenesis Irritable bowel syndrome has no significant structural abnormality and pathogenic mechanism causing disease is uncertain. Following are few hypotheses associated with IBS- Gastrointestinal tract motor abnormalities (e.g., abnormal transit […]

The osmotic fragility test (OFT) is performed to measure erythrocyte resistance to hemolysis in varying levels of serial dilution of a saline solution/ hypotonic solution. When cells are exposed to a hypotonic environment, water enters the cell and causes swelling and cell lysis. The osmotic lysis of erythrocytes depends upon surface area to volume ratio […]

Hereditary spherocytosis (HS) is the most common inherited red cell membrane disorder causing chronic hemolytic anemia. This defect lead to the formation of spherocytes, which are nondeformable cells. Pathogenesis It is commonly inherited in autosomal dominant pattern. It caused by a deficiency in red blood cell membrane proteins spectrin, ankyrin, or Band 3.1. These are […]

Inflammatory bowel disease is a chronic relapsing inflammatory disorder of intestine. It includes two major forms, Crohn’s disease and ulcerative colitis. Although the exact etiology of IBD is unknown, it involves a complex interaction between the genetic, environmental or microbial factors and the immune responses. Following are major factors associated with Inflammatory Bowel Disease- Genetic […]

Tetralogy of Fallot is a congenital cardiac defect caused by anterosuperior displacement of the infundibular septum, characterized by four defects occurring together- Right ventricular outflow tract obstruction (subpulmonic stenosis) Ventricular septal defect (VSD) Overriding of the VSD by the aorta Right ventricular hypertrophy (RVH) Pathophysiology Conotruncal abnormality from failure of neural crest cells to migrate. […]

DiGeorge syndrome arises because of a microdeletion of chromosome 22q11.2. This deletion of genetic material leads to a developmental defect that involves the third and fourth pharyngeal pouches. Hypoplasia of the thymus and parathyroid glands, aortic arch as well as facial malformations and learning difficulties are most common abnormalities seen in such cases. Patients have […]

Marfan syndrome is an autosomal dominant disorder causing defect in an extracellular glycoprotein called fibrillin-1. Fibrillin is encoded by the FBN1 gene on chromosome 15.   Pathogenesis Fibrillin is secreted by fibroblasts and is the major component of microfibrils. Microfibrils serve as scaffolding for the deposition of tropoelastin, an integral component of elastic fibers. Microfibrils […]

Sheehan’s syndrome is postpartum hypopituitarism caused by necrosis of the pituitary gland. It is usually the result of severe hypotension or shock caused by massive hemorrhage during or after delivery. Risk factors Increased chance of severe blood loss, at the time of childbirth is the most likely cause. Following are most associated risk factors- Abruptio […]

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy affecting hepatocytes. … … Risk factors HCC is a prototypical inflammation-associated cancer, and inflammation causes immune microenvironment and oxidative stress to Induce DNA damage which plays pivotal roles in inducing mutations. Cirrhosis (most common cause) Chronic hepatitis B infection Chronic hepatitis C infection Alcohol abuse […]