Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
          Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
           
        
There are three main types of primary hyperoxaluria, each associated with specific metabolic defects. Type 1 is the most common and rapidly progressing form, accounting for about 80% of all cases. Type 2 and 3 account for about approximately 10% each of the population.
Mutations in these genes cause a decreased production or activity of the proteins they make, which stops the normal breakdown of glyoxylate.
The evidence linking vitamin C supplements with an increased rate of kidney stones is inconclusive. The excess dietary intake of vitamin C might increase the risk of calcium oxalate stone formation, in practice this is rarely encountered. The link between vitamin D intake and kidney stones is also tenuous. Excessive vitamin D supplementation may increase the risk of stone formation by increasing the intestinal absorption of calcium; correction of a deficiency does not.
Renal tuberculosis
And other causes of hypercalcemia (and thus hypercalciuria)
- Immobilization (leading to hypercalcemia and hypercalciuria)
- Milk-alkali syndrome
- Hypervitaminosis D
- Multiple myeloma
The prognosis of nephrocalcinosis is determined by the underlying cause. Most cases of nephrocalcinosis do not progress to end stage renal disease, however if not reated it can lead to renal dysfunction this includes primary hyperoxaluria, hypomagnesemic hypercalciuric nephrocalcinosis and Dent's disease. Once nephrocalcinosis is found, it is unlikely to be reversed, however, partial reversal has been reported in patients who have had successful treatment of hypercalciuria and hyperoxaluria following corrective intestinal surgery.
The main therapeutic approach to primary hyperoxaluria is still restricted to symptomatic treatment, i.e. kidney transplantation once the disease has already reached mature or terminal stages. However, through genomics and proteomics approaches, efforts are currently being made to elucidate the kinetics of AGXT folding which has a direct bearing on its targeting to appropriate subcellular localization. Secondary hyperoxaluria is much more common than primary hyperoxaluria, and should be treated by limiting dietary oxalate and providing calcium supplementation. A child with primary hyperoxaluria was treated with a liver and kidney transplant. A favorable outcome is more likely if a kidney transplant is complemented by a liver transplant, given the disease originates in the liver.
The buildup of oxalate in the body causes increased renal excretion of oxalate (hyperoxaluria), which in turn results in renal and bladder stones. Stones cause urinary obstruction (often with severe and acute pain), secondary infection of urine and eventually kidney damage.
Oxalate stones in primary hyperoxaluria tend to be severe, resulting in relatively early kidney damage (say teenage, early adulthood), which impairs the excretion of oxalate leading to a further acceleration in accumulation of oxalate in the body.
After the development of renal failure patients may get deposits of oxalate in the bones, joints and bone marrow. Severe cases may develop haematological problems such as anaemia and thrombocytopaenia. The deposition of oxalate in the body is sometimes called "oxalosis" to be distinguished from "oxaluria" which refers to oxalate in the urine.
Renal failure is a serious complication requiring treatment in its own right. Dialysis can control renal failure but tends to be inadequate to dispose of excess oxalate. Renal transplant is more effective and this is the primary treatment of severe hyperoxaluria. Liver transplantation (often in addition to renal transplant) may be able to control the disease by correcting the metabolic defect.
In a proportion of patients with primary hyperoxaluria type 1 (about 5%), pyridoxine treatment (vitamin B6) may decrease oxalate excretion and prevent kidney stone formation.
Primary hyperoxaluria is an autosomal recessive disease, meaning both copies of the gene contain the mutation. Both parents must have one copy of this mutated gene to pass it on to their child, but they do not typically show signs or symptoms of the disease.
Although kidney stones do not often occur in children, the incidence is increasing. These stones are in the kidney in two thirds of reported cases, and in the ureter in the remaining cases. Older children are at greater risk independent of sex.
As with adults, most pediatric kidney stones are predominantly composed of calcium oxalate; struvite and calcium phosphate stones are less common. Calcium oxalate stones in children are associated with high amounts of calcium, oxalate, and magnesium in acidic urine.
Type I (PH1) is associated with AGXT protein, a key enzyme involved in breakdown of oxalate. PH1 is also an example of a protein mistargeting disease, wherein AGXT shows a trafficking defect: instead of being trafficked to peroxisomes, it is targeted to mitochondria, where it is metabolically deficient despite being catalytically active. Type II is associated with GRHPR.
It is also a complication of jejunoileal bypass, or in any patient who has lost much of the ileum with an intact colon. This is due to excessive absorption of oxalate from the colon.
A ciliopathy is a genetic disorder of the cellular cilia or the cilia anchoring structures, the basal bodies, or of ciliary function.
Although ciliopathies are usually considered to involve proteins that localize to motile and/or immotile (primary) cilia or centrosomes, it is possible for ciliopathies to be associated with proteins such as XPNPEP3, which localizes to mitochondria but is believed to affect ciliary function through proteolytic cleavage of ciliary proteins.
Significant advances in understanding the importance of cilia were made beginning in the mid-1990s. However, the physiological role that this organelle plays in most tissues remains elusive. Additional studies of how ciliary dysfunction can lead to such severe disease and developmental pathologies is a subject of current research.
A wide variety of symptoms are potential clinical features of ciliopathy.
- Chemosensation abnormalities, typically via ciliated epithelial cellular dysfunction.
- Defective thermosensation or mechanosensation, often via ciliated epithelial cellular dysfunction.
- Cellular motility dysfunction
- Issues with displacement of extracellular fluid
- Paracrine signal transduction abnormalities
In organisms of normal health, cilia are critical for:
- development
- homeostasis
- reproduction
Radiation exposure increases the risk of primary hyperparathyroidism. A number of genetic conditions including multiple endocrine neoplasia syndromes also increase the risk.
In endocrinology, the terms 'primary' and 'secondary' are used to describe the abnormality (e.g., elevated aldosterone) in relation to the defect, "i.e.", the tumor's location. Hyperaldosteronism can also be caused by plant poisoning, where the patient has been exposed to too much licorice. Licorice is a perennial herb that is used in making candies and in cooking other desserts because of its sweet taste. It contains the chemical glycyrrhizin, which has medicinal uses, but at higher levels it can be toxic. It has the potential for causing problems with sodium and potassium in the body. It also interferes with the enzyme in the kidneys that converts cortisol to cortisone.
The most common cause of primary hyperparathyroidism is a sporadic, single parathyroid adenoma resulting from a clonal mutation (~97%). Less common are parathyroid hyperplasia (~2.5%), parathyroid carcinoma (malignant tumor), and adenomas in more than one gland (together ~0.5%).
Primary hyperparathyroidism is also a feature of several familial endocrine disorders: Multiple endocrine neoplasia type 1 and type 2A (MEN type 1 and MEN type 2A), and familial hyperparathyroidism.
Genetic associations include:
In all cases, the disease is idiopathic, but is thought to involve inactivation of tumor suppressor genes (Menin gene in MEN1), or involve gain of function mutations (RET proto-oncogene MEN 2a).
Recently, it was demonstrated that liquidators of the Chernobyl power plant are faced with a substantial risk of primary hyperparathyroidism, possibly caused by radioactive strontium isotopes.
Primary hyperparathyroidism can also result from pregnancy. It is apparently very rare, with only about 110 cases have so far been reported in world literature, but this is probably a considerable underestimate of its actual prevalence in pregnant women.
Tertiary hyperparathyroidism is seen in patients with long-term secondary hyperparathyroidism, which eventually leads to hyperplasia of the parathyroid glands and a loss of response to serum calcium levels. This disorder is most often seen in patients with chronic renal failure and is an autonomous activity.
When taking a blood test, the aldosterone-to-renin ratio is abnormally increased in primary hyperaldosteronism, and decreased or normal but with high renin in secondary hyperaldosteronism.
D-Glyceric Acidemia should not be confused with L-Glyceric Acidemia (a.k.a. L-glyceric aciduria, a.k.a. primary hyperoxaluria type II ), which is associated with mutations in the "GRHPR" (encoding for the enzyme 'glyoxylate reductase/hydroxypyruvate reductase').
Glycerate kinase is an enzyme that catalyzes the conversion of D-glyceric acid (a.k.a. D-glycerate) to 2-phosphoglycerate. This conversion is an intermediary reaction found in several metabolic pathways, including the degradation (break-down; catabolism) of serine, as well as the breakdown of fructose.
A deficiency in glycerate kinase activity leads to the accumulation of D-glyceric acid (a.k.a. D-glycerate) in bodily fluids and tissues. D-glyceric acid can be measured in a laboratory that performs "analyte testing" for "organic acids" in blood (plasma) and urine.
Symptoms of the disease (in its most severe form) include progressive neurological impairment, mental/motor retardation, hypotonia, seizures, failure to thrive and metabolic acidosis.
The incidence of primary hyperparathyroidism is approximately 1 per 1,000 people (0.1%), while there are 25-30 new cases per 100,000 people per year in the United States. The prevalence of primary hyperparathyroidism has been estimated to be 3 in 1000 in the general population and as high as 21 in 1000 in postmenopausal women. It is almost exactly three times as common in women as men.
Primary hyperparathyroidism is associated with increased all-cause mortality.
Although primary polydipsia is usually categorised as psychogenic, there are some rare non-psychogenic causes. An example is polydipsia found in patients with autoimmune chronic hepatitis with severely elevated globulin levels. Evidence for the thirst being non-psychogenic is gained from the fact that it disappears after treatment of the underlying disease.
Psychogenic polydipsia is found in patients with mental illnesses, most commonly schizophrenia, but also anxiety disorders and rarely affective disorders, anorexia nervosa and personality disorders. PPD occurs in between 6% and 20% of psychiatric inpatients. It may also be found in people with developmental disorders, such as those with autism. While psychogenic polydipsia is usually not seen outside the population of those with serious mental disorders, it may occasionally be found among others in the absence of psychosis, although there is no existent research to document this other than anecdotal observations. Such persons typically prefer to possess bottled water that is ice-cold, consume water and other fluids at excessive levels. However, a preference for ice-cold water is also seen in diabetes insipidus.
The condition is due to:
- Bilateral idiopathic (micronodular) adrenal hyperplasia (66%)
- Adrenal adenoma (Conn's syndrome) (33%)
- Primary (unilateral) adrenal hyperplasia—2% of cases
- Aldosterone-producing adrenocortical carcinoma—<1% of cases
- Familial Hyperaldosteronism (FH)
- Glucocorticoid-remediable aldosteronism (FH type I)—<1% of cases
- FH type II (APA or IHA)—<2% of cases
- Ectopic aldosterone-producing adenoma or carcinoma—< 0.1% of cases
Primary hyperaldosteronism can be mimicked by Liddle syndrome, and by ingestion of licorice and other foods containing glycyrrhizin. In one case report, hypertension and quadriparesis resulted from intoxication with a non-alcoholic pastis (an anise-flavored aperitif containing glycyrrhizinic acid).
In 2016 the United States Preventive Services Task Force concluded that testing the general population under the age of 40 without symptoms is of unclear benefit.
Hypertriglyceridemia denotes high ("hyper-") blood levels ("-emia") of triglycerides, the most abundant fatty molecule in most organisms. Elevated levels of triglycerides are associated with atherosclerosis, even in the absence of hypercholesterolemia (high cholesterol levels), and predispose to cardiovascular disease. Very high triglyceride levels also increase the risk of acute pancreatitis. Hypertriglyceridemia itself is usually symptomless, although high levels may be associated with skin lesions known as "xanthomas".
The diagnosis is made on blood tests, often performed as part of screening. Once diagnosed, other blood tests are usually required to determine whether the raised triglyceride level is caused by other underlying disorders ("secondary hypertriglyceridemia") or whether no such underlying cause exists ("primary hypertriglyceridaemia"). There is a hereditary predisposition to both primary and secondary hypertriglyceridemia.
Weight loss and dietary modification may improve hypertriglyceridemia. The decision to treat hypertriglyceridemia with medication depends on the levels and on the presence of other risk factors for cardiovascular disease. Very high levels that would increase the risk of pancreatitis is treated with a drug from the fibrate class. Niacin and omega-3 fatty acids as well as drugs from the statin class may be used in conjunction, with statins being the main drug treatment for moderate hypertriglyceridemia where reduction of cardiovascular risk is required.
A number of conditions may cause the appearance of livedo reticularis:
- Cutis marmorata telangiectatica congenita, a rare congenital condition
- Sneddon syndrome – association of livedoid vasculitis and systemic vascular disorders, such as strokes, due to underlying genetic cause
- Idiopathic livedo reticularis – the most common form of livedo reticularis, completely benign condition of unknown cause affecting mostly young women during the winter: It is a lacy purple appearance of skin in extremities due to sluggish venous blood flow. It may be mild, but ulceration may occur later in the summer.
- Secondary livedo reticularis:
- Vasculitis autoimmune conditions:
- Livedoid vasculitis – with painful ulceration occurring in the lower legs
- Polyarteritis nodosa
- Systemic lupus erythematosus
- Dermatomyositis
- Rheumatoid arthritis
- Lymphoma
- Pancreatitis
- Chronic pancreatitis
- Tuberculosis
- Drug-related:
- Adderall (side effect)
- Amantadine (side effect)
- Bromocriptine (side effect)
- Beta IFN treatment, "i.e." in multiple sclerosis
- Livedo reticularis associated with rasagiline
- Methylphenidate and dextroamphetamine-induced peripheral vasculopathy
- Gefitinib
- Obstruction of capillaries:
- Cryoglobulinaemia – proteins in the blood that clump together in cold conditions
- Antiphospholipid syndrome due to small blood clots
- Hypercalcaemia (raised blood calcium levels which may be deposited in the capillaries)
- Haematological disorders of polycythaemia rubra vera or thrombocytosis (excessive red cells or platelets)
- Infections (syphilis, tuberculosis, Lyme disease)
- Associated with acute renal failure due to cholesterol emboli status after cardiac catheterization
- Arteriosclerosis (cholesterol emboli) and homocystinuria (due to Chromosome 21 autosomal recessive Cystathionine beta synthase deficiency)
- Intra-arterial injection (especially in drug addicts)
- Ehlers-Danlos syndrome – connective tissue disorder, often with many secondary conditions, may be present in all types
- Pheochromocytoma
- Livedoid vasculopathy and its association with factor V Leiden mutation
- FILS syndrome (polymerase ε1 mutation in a human syndrome with facial dysmorphism, immunodeficiency, livedo, and short stature)
- Primary hyperoxaluria, oxalosis (oxalate vasculopathy)
- Cytomegalovirus infection (very rare clinical form, presenting with persistent fever and livedo reticularis on the extremities and cutaneous necrotizing vasculitis of the toes)
- Generalized livedo reticularis induced by silicone implants for soft tissue augmentation
- As a rare skin finding in children with Down syndrome
- Idiopathic livedo reticularis with polyclonal IgM hypergammopathy
- CO angiography (rare, reported case)
- A less common skin lesion of Churg-Strauss syndrome
- Erythema nodosum-like cutaneous lesions of sarcoidosis showing livedoid changes in a patient with sarcoidosis and Sjögren's syndrome
- Livedo vasculopathy associated with IgM antiphosphatidylserine-prothrombin complex antibody
- Livedo vasculopathy associated with plasminogen activator inhibitor-1 promoter homozygosity and prothrombin G20210A heterozygosity
- As a first sign of metastatic breast carcinoma (very rare)
- Livedo reticularis associated with renal cell carcinoma (rare)
- Buerger's disease (as an initial symptom)
- As a rare manifestation of Graves hyperthyroidism
- Associated with pernicious anaemia
- Moyamoya disease (a rare, chronic cerebrovascular occlusive disease of unknown cause, characterized by progressive stenosis of the arteries of the circle of Willis leading to an abnormal capillary network and resultant ischemic strokes or cerebral hemorrhages)
- Associated with the use of a midline catheter
- Familial primary cryofibrinogenemia.