|
Neonatal Cholestasis
Neonatal cholestasis refers to elevated levels of conjugated bilirubin identified in newborn infants within the first few months of life. Conjugated hyperbilirubinemia is clinically defined as >20% of total serum bilirubin or conjugated bilirubin concentration greater than 1.0 mg/dL regardless of total serum bilirubin concentration. The differential diagnosis for neonatal cholestasis can vary extensively. However, the underlying disease pathology is caused by improper transport and/or defects in excretion of bile from hepatocytes leading to an accumulation of conjugated bilirubin in the body. Generally, symptoms associated with neonatal cholestasis can vary based on the underlying cause of the disease. However, most infants affected will present with jaundice, scleral icterus, failure to thrive, acholic or pale stools, and dark urine. Epidemiology Neonatal cholestasis can present in newborn infants within the first few months of life. The incidence of neonatal cholestasis is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bilirubin
Bilirubin (BR) (Latin for "red bile") is a red-orange compound that occurs in the normal catabolic pathway that breaks down heme in vertebrates. This catabolism is a necessary process in the body's clearance of waste products that arise from the destruction of aged or abnormal red blood cells. In the first step of bilirubin synthesis, the heme molecule is stripped from the hemoglobin molecule. Heme then passes through various processes of porphyrin catabolism, which varies according to the region of the body in which the breakdown occurs. For example, the molecules excreted in the urine differ from those in the feces. The production of biliverdin from heme is the first major step in the catabolic pathway, after which the enzyme biliverdin reductase performs the second step, producing bilirubin from biliverdin.Boron W, Boulpaep E. Medical Physiology: a cellular and molecular approach, 2005. 984–986. Elsevier Saunders, United States. Ultimately, bilirubin is broken down within ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxisomal Disorders
Peroxisomal disorders represent a class of medical conditions caused by defects in peroxisome functions. This may be due to defects in single enzymes important for peroxisome function or in peroxins, proteins encoded by ''PEX'' genes that are critical for normal peroxisome assembly and biogenesis. Peroxisome biogenesis disorders Peroxisome biogenesis disorders (PBDs) include the Zellweger syndrome spectrum (PBD-ZSD) and rhizomelic chondrodysplasia punctata type 1 (RCDP1). PBD-ZSD represents a continuum of disorders including infantile Refsum disease, neonatal adrenoleukodystrophy, and Zellweger syndrome. Collectively, PBDs are autosomal recessive developmental brain disorders that also result in skeletal and craniofacial dysmorphism, liver dysfunction, progressive sensorineural hearing loss, and retinopathy. PBD-ZSD is most commonly caused by mutations in the ''PEX1'', ''PEX6'', ''PEX10'', ''PEX12'', and ''PEX26'' genes. This results in the over-accumulation of very long chain fatt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choledochal Cysts
Choledochal cysts (a.k.a. bile duct cyst) are congenital conditions involving cystic dilatation of bile ducts. They are uncommon in western countries but not as rare in East Asian nations like Japan and China. Signs and symptoms Most patients have symptoms in the first year of life. It is rare for symptoms to be undetected until adulthood, and usually adults have associated complications. The classic triad of intermittent abdominal pain, jaundice, and a right upper quadrant abdominal mass is found only in minority of patients. In infants, choledochal cysts usually lead to obstruction of the bile ducts and retention of bile. This leads to jaundice and an enlarged liver. If the obstruction is not relieved, permanent damage may occur to the liver - scarring and cirrhosis - with the signs of portal hypertension (obstruction to the flow of blood through the liver) and ascites (fluid accumulation in the abdomen). There is an increased risk of cancer in the wall of the cyst. In older ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Bile Duct
The common bile duct, sometimes abbreviated as CBD, is a duct in the gastrointestinal tract of organisms that have a gallbladder. It is formed by the confluence of the common hepatic duct and cystic duct and terminates by uniting with pancreatic duct, forming the ampulla of Vater. The flow of bile from the ampulla of Vater into the duodenum is under the control of the sphincter of Oddi. When the sphincter of Oddi is closed, newly synthesized bile from the liver is forced into storage in the gallbladder. When open, the stored and concentrated bile (now mixed with pancreatic secretions) exits into the duodenum and takes part in digestion. This conduction of bile is the main function of the common bile duct. The hormone cholecystokinin, when stimulated by a fatty meal, promotes bile secretion by increased production of hepatic bile, contraction of the gallbladder, and relaxation of the sphincter of Oddi. Clinical significance Several problems can arise within the common bil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cystic Duct
The cystic duct is the short duct that joins the gallbladder to the common hepatic duct. It usually lies next to the cystic artery. It is of variable length. It contains 'spiral valves of Heister', which do not provide much resistance to the flow of bile. Function Bile can flow in both directions between the gallbladder and the common bile duct and the hepatic duct. In this way, bile is stored in the gallbladder in between meal times. The hormone cholecystokinin, when stimulated by a fatty meal, promotes bile secretion by increased production of hepatic bile, contraction of the gall bladder, and relaxation of the Sphincter of Oddi. Clinical significance Gallstones can enter and obstruct the cystic duct, preventing the flow of bile. The increased pressure in the gallbladder leads to swelling and pain. This pain, known as biliary colic, is sometimes referred to as a gallbladder "attack" because of its sudden onset. During a cholecystectomy, the cystic duct is clipped two or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Hepatic Duct
The common hepatic duct is the first part of the biliary tract. It joins the cystic duct coming from the gallbladder to form the common bile duct. Structure The common hepatic duct is the first part of the biliary tract. It is formed by the convergence of the right hepatic duct (which drains bile from the right functional lobe of the liver) and the left hepatic duct (which drains bile from the left functional lobe of the liver). It then joins the cystic duct coming from the gallbladder to form the common bile duct. The duct is usually 6–8 cm long. The common hepatic duct is about 6 mm in diameter in adults, with some variation.Gray's Anatomy, 39th ed, p. 1228 The inner surface is covered in a simple columnar epithelium. Variation Around 1.7% of people have additional accessory hepatic ducts that join onto the common hepatic duct. Rarely, the common hepatic duct joins onto the gallbladder directly, leading to illness. Function The hepatic duct is part of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panhypopituitarism
Hypopituitarism is the decreased (''hypo'') secretion of one or more of the eight hormones normally produced by the pituitary gland at the base of the brain. If there is decreased secretion of one specific pituitary hormone, the condition is known as selective hypopituitarism. If there is decreased secretion of most or all pituitary hormones, the term panhypopituitarism (''pan'' meaning "all") is used. The signs and symptoms of hypopituitarism vary, depending on which hormones are undersecreted and on the underlying cause of the abnormality. The diagnosis of hypopituitarism is made by blood tests, but often specific scans and other investigations are needed to find the underlying cause, such as tumors of the pituitary, and the ideal treatment. Most hormones controlled by the secretions of the pituitary can be replaced by tablets or injections. Hypopituitarism is a rare disease, but may be significantly underdiagnosed in people with previous traumatic brain injury. The first des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothyroidism
Hypothyroidism (also called ''underactive thyroid'', ''low thyroid'' or ''hypothyreosis'') is a disorder of the endocrine system in which the thyroid gland does not produce enough thyroid hormone. It can cause a number of symptoms, such as poor ability to tolerate cold, a feeling of tiredness, constipation, slow heart rate, depression, and weight gain. Occasionally there may be swelling of the front part of the neck due to goiter. Untreated cases of hypothyroidism during pregnancy can lead to delays in growth and intellectual development in the baby or congenital iodine deficiency syndrome. Worldwide, too little iodine in the diet is the most common cause of hypothyroidism. Hashimoto's thyroiditis is the most common cause of hypothyroidism in countries with sufficient dietary iodine. Less common causes include previous treatment with radioactive iodine, injury to the hypothalamus or the anterior pituitary gland, certain medications, a lack of a functioning thyroid at bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syphilis
Syphilis () is a sexually transmitted infection caused by the bacterium ''Treponema pallidum'' subspecies ''pallidum''. The signs and symptoms of syphilis vary depending in which of the four stages it presents (primary, secondary, latent, and tertiary). The primary stage classically presents with a single chancre (a firm, painless, non-itchy skin ulceration usually between 1 cm and 2 cm in diameter) though there may be multiple sores. In secondary syphilis, a diffuse rash occurs, which frequently involves the palms of the hands and soles of the feet. There may also be sores in the mouth or vagina. In latent syphilis, which can last for years, there are few or no symptoms. In tertiary syphilis, there are gummas (soft, non-cancerous growths), neurological problems, or heart symptoms. Syphilis has been known as "the great imitator" as it may cause symptoms similar to many other diseases. Syphilis is most commonly spread through sexual activity. It may also be transmi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuberculosis
Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in which case it is known as latent tuberculosis. Around 10% of latent infections progress to active disease which, if left untreated, kill about half of those affected. Typical symptoms of active TB are chronic cough with blood-containing mucus, fever, night sweats, and weight loss. It was historically referred to as consumption due to the weight loss associated with the disease. Infection of other organs can cause a wide range of symptoms. Tuberculosis is spread from one person to the next through the air when people who have active TB in their lungs cough, spit, speak, or sneeze. People with Latent TB do not spread the disease. Active infection occurs more often in people with HIV/AIDS and in those who smoke. Diagnosis of active TB is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echovirus
Echovirus is a polyphyletic group of viruses associated with enteric disease in humans. The name is derived from "enteric cytopathic human orphan virus". These viruses were originally not associated with disease, but many have since been identified as disease-causing agents. The term "echovirus" was used in the scientific names of numerous species, but all echoviruses are now recognized as strains of various species, most of which are in the family ''Picornaviridae''. List of echoviruses Thirty-four echoviruses are known: * Human echoviruses 1–7, 9, 11–21, 24–27, and 29–33 are strains of the species ''Enterovirus B'' of the genus ''Enterovirus''. * Human echovirus 8 was shown to be identical to Human echovirus 1 and was abolished as a species. * Human echovirus 10 was reclassified as a strain of the species ''Reovirus type 1'', currently named ''Mammalian orthoreovirus'' of the genus ''Orthoreovirus'', which belongs to the family ''Reoviridae''. As such, Human echovirus 10 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenovirus
Adenoviruses (members of the family ''Adenoviridae'') are medium-sized (90–100 nm), nonenveloped (without an outer lipid bilayer) viruses with an icosahedral nucleocapsid containing a double-stranded DNA genome. Their name derives from their initial isolation from human adenoids in 1953. They have a broad range of vertebrate hosts; in humans, more than 50 distinct adenoviral serotypes have been found to cause a wide range of illnesses, from mild respiratory infections in young children (known as the common cold) to life-threatening multi-organ disease in people with a weakened immune system. Virology Classification This family contains the following genera: * '' Atadenovirus'' * '' Aviadenovirus'' * '' Ichtadenovirus'' * '' Mastadenovirus'' (including all human adenoviruses) * '' Siadenovirus'' * '' Testadenovirus'' Diversity In humans, currently there are 88 human adenoviruses (HAdVs) in seven species (Human adenovirus A to G): * A: 12, 18, 31 * B: 3, 7, 11, 14, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
