Complete retention of urine in infancy; a common cause

Urination, or micturition involves the coordination of the bladder's detrusor muscle and two sphincters to ensure controlled bladder emptying.
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating urine...

The urinary system is responsible for eliminating waste and excess fluids from the body. However, disorders of the urinary system can arise due to various reasons like infections, stress, age, congenital abnormalities, and lifestyle.
Urinary tract infections (UTIs) are one of the most common urinary system disorders. They are caused by bacteria that enter the urethra and can spread to the bladder resulting in cystitis. Pyelonephritis is the result of a UTI that has ascended to the level of the...

Definition Diabetes insipidus is a disorder marked by the production of large amounts of dilute urine because of impaired vasopressin production, release, or kidney response. The lack of effective vasopressin action limits water reabsorption in the renal collecting ducts, which leads to excessive urinary water loss and intense thirst.Clinical PresentationIndividuals with diabetes insipidus report persistent thirst and very high urine output. In severe cases, fluid intake can reach up to 20...

Normally, water balance is maintained through three interconnected mechanisms: the hypothalamic thirst center, the synthesis and release of antidiuretic hormone (ADH, or vasopressin), and the kidneys' responsiveness to this hormone. ADH is synthesized in the hypothalamus, released from the posterior pituitary, and acts on the distal nephron, allowing water reabsorption and concentrated urine production.Diabetes Insipidus and Its TypesIn diabetes insipidus (DI), this regulatory system is...

Osmolality refers to the number of solute particles per kilogram of solvent in a solution. Plasma osmolality specifically indicates the total number of solute particles per kilogram of water in blood plasma. This value reflects the body's hydration status and is tightly regulated through mechanisms controlling water intake and output. While water consumption is a conscious decision, the body has intrinsic regulatory systems to maintain fluid balance. Dehydration, a state of water deficit...

Urine formation is an essential function of the human body. It plays a critical role in maintaining homeostasis by regulating the volume and composition of body fluids. The kidneys, the primary organs involved in this process, filter blood to remove waste products and excess substances, ultimately producing urine.
Glomerular Filtration
The first stage in urine formation is glomerular filtration. Each kidney contains approximately 1 million nephrons, the functional units of filtration, with a...