Gunther disease, or Gunther’s disease, is a congenital form of erythropoietic porphyria. It is a rare, autosomal recessive[1] metabolic disorder of heme caused by deficiency of the enzyme uroporphyrinogen cosynthetase.[2]

The disorder is named after the scientist who discovered it, Hans Gunther.[3]

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Growth Hormone Deficiency (GHD) is a medical condition in which the body does not produce enough growth hormone (GH). Growth hormone, also called somatotropin, is a polypeptide hormone which stimulates growth and cell reproduction. HGH also refers to human growth hormone but this older abbreviation has begun to develop paradoxical connotations, particularly in relation to the peddling of medically unnecessary GH supplementation (so-called HGH quackery).

Growth hormone deficiency has different effects at different ages. In newborn infants the primary manifestations may be hypoglycemia or micropenis, while in later infancy and childhood, growth failure is more likely. Deficiency in adults is rare, but may feature diminished lean body mass, poor bone density, and a number of physical and psychological symptoms. Psychological symptoms include poor memory, social withdrawal, and depression, while physical symptoms may include loss of strength, stamina, and musculature. Other hormonal or glandular disorders frequently coincide with diminished growth hormone production.

GH deficiency can be treated by growth hormone replacement.

GH deficiency can be congenital or acquired in childhood or adult life. It can be partial or complete. It is usually permanent, but sometimes transient. It may be an isolated deficiency or occur in association with deficiencies of other pituitary hormones.

The term hypopituitarism is often used interchangeably with GH deficiency by endocrinologists but more often denotes GH deficiency plus deficiency of at least one other anterior pituitary hormone. When GH deficiency (usually with other anterior pituitary deficiencies) is associated with posterior pituitary hormone deficiency (usually diabetes insipidus) the condition is termed panhypopituitarism.

The incidence of idiopathic GHD in infants is about 1 in every 3800 live births[1], and rates in older children are rising as more children survive childhood cancers which are treated with radiotherapy, although exact rates are hard to obtain. [2] Severe prenatal deficiency of GH, as occurs in congenital hypopituitarism, has little effect on fetal growth. However, prenatal and congenital deficiency can reduce the size of a male’s penis, especially when gonadotropins are also deficient. Besides micropenis, additional consequences of severe deficiency in the first days of life can include hypoglycemia and exaggerated jaundice (both direct and indirect hyperbilirubinemia). Female infants will lack the microphallus of course but may suffer from hypoglycemia and jaundice.

Even congenital GH deficiency does not usually impair length growth until after the first few months of life. From late in the first year until mid teens, poor growth and/or shortness is the hallmark of childhood GH deficiency. Growth is not as severely affected in GH deficiency as in untreated hypothyroidism, but growth at about half the usual velocity for age is typical. It tends to be accompanied by delayed physical maturation so that bone maturation and puberty may be several years delayed. When severe GH deficiency is present from birth and never treated, adult heights can be as short as 48-58 inches (122-147 cm).

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Granuloma annulare is a chronic skin disease consisting of a rash with reddish bumps arranged in a circle or ring. Granuloma annulare is different from warts, and cryotherapy treatment will not work. It most often affects children, young and older adults and it is slightly more common in females (60/40 ratio).

The condition is usually seen in otherwise healthy people. Occasionally, it may be associated with diabetes or thyroid disease.

Its cause is unknown.[1]

Granuloma annulare is usually asymptomatic, but the rash may burn and be itchy. Patients usually notice a ring of small, firm bumps (papules) over the backs of the forearms, hands or feet, often centered around joints or knuckles. The bumps are caused by the clustering of T cells below the skin. Occasionally, multiple rings may be found. Rarely, granuloma annulare may appear as a firm nodule under the skin of the arms or legs.

Because granuloma annulare is usually asymptomatic, treatment may not be necessary except for cosmetic reasons.[2] Most lesions of granuloma annulare disappear in pre-pubertal patients with no treatment within two years while older patients (50+) have rings for upwards of 20 years. The appearance of new rings years later is not uncommon.

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A goitre (BrE), or goiter (AmE) (Latin struma), also called a bronchocele, is a swelling in the neck (just below the Adam’s apple or larynx) due to an enlarged thyroid gland.

They are classified in different ways:

Other type of classification:

Worldwide, the most common cause for goiter is iodine deficiency. In countries that use iodized salt, Hashimoto’s thyroiditis becomes the most common cause.

Other causes are:

Iodine is necessary for the synthesis of the thyroid hormones thyroxine (T4) and triiodothyronine (T3). In endemic goitre, iodine deficiency leaves the thyroid gland unable to produce its hormones because the hormones are made out of iodine. When levels of thyroid hormones fall, thyrotropin-releasing hormone (TRH) is produced by the hypothalamus. TRH then prompts the pituitary gland to make thyrotropin or thyroid stimulating hormone (TSH), which stimulates the thyroid gland’s production of T4 and T3. It also causes the thyroid gland to grow in size by increasing cell division.

Goiter is more common among women, but this includes the many types of goitre caused by autoimmune problems, and not only those caused by simple lack of iodine.

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Glycogen storage disease type VI is a type of glycogen storage disease caused by a deficiency in liver glycogen phosphorylase.

It is also known as “Hers’ disease”, after Henri G. Hers, who characterized it in 1959.[1][2]

Patients generally have a benign course, and typically present with hepatomegaly[3] and growth retardation early in childhood. Mild hypoglycemia, hyperlipidemia, and hyperketosis may occur. Lactic acid and uric acid levels are normal.

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Glycogen storage disease type IV is a very rare hereditary metabolic disorder.

It is also known as:-

The eponym “Andersen’s disease” is sometimes used, for Dorothy Hansine Andersen.[1][2][3]

It is a result of the absence of the glycogen branching enzyme amylo-1,4-1,6 transglucosidase, which is critical in the production of glycogen. This leads to very long unbranched glucose chains being stored in glycogen. The long unbranched molecules (known as amylose) have a low solubility which leads to glycogen precipitation in the liver. These deposits subsequently build up in the body tissue, especially the heart and liver. The end result is liver failure and eventual death occurring in the first year of life.

See main article: Glycogen branching enzyme deficiency

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Glycogen storage disease (synonyms: glycogenosis, dextrinosis) is any one of several inborn errors of metabolism that result from enzyme defects that affect the processing of glycogen synthesis or breakdown within muscles, liver, and other cell types.

There are nine diseases that are commonly considered to be glycogen storage diseases. (Although glycogen synthase deficiency does not result in storage of extra glycogen in the liver, it is often classified with the GSDs as type 0 because it is another defect of glycogen storage and can cause similar problems.)

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Glutaric acidemia type 1 (or “Glutaric Aciduria”, “GA1″, or “GAT1″) is an inherited disorder in which the body is unable to break down completely the amino acids lysine, hydroxylysine and tryptophan. Excessive levels of their intermediate breakdown products (glutaric acid, glutaryl-CoA, 3-hydroxyglutaric acid, glutaconic acid) can accumulate and cause damage to the brain (and also other organs[1]), but particularly the basal ganglia, which are regions that help regulate movement. GA1 causes secondary carnitine deficiency, as glutaric acid, like other organic acids, is detoxified by carnitine. Mental retardation may also occur.

The severity of glutaric acidemia type 1 varies widely; some individuals are only mildly affected, while others have severe problems. GA1 can be defined as two clinical entities: GA1 before the encephalopathic crisis and GA1 after the encephalopathic crisis.

Babies with glutaric acidemia type 1 often are born with unusually large heads (macrocephaly). Macrocephaly is amongst the earliest signs of GA1. It is thus important to investigate all cases of macrocephaly of unknown origins for GCDH deficiency[2][3], given the importance of the early diagnosis of GA1[4]. Macrocephaly is a “pivotal clinical sign” of many neurological diseases. Physicians and parents should be aware of the benefits of investigating for an underlying neurological disorder, particularly a neurometabolic one, in children with head circumferences in the highest percentiles.

Affected individuals may have difficulty moving and may experience spasms, jerking, rigidity or decreased muscle tone and muscle weakness (which may be the result of secondary carnitine deficiency). Glutaric aciduria type 1, in many cases, can be defined as a cerebral palsy of genetic origins.

A common way to manage striatal necrosis is to provide special seating. These special wheelchairs are designed to limit abnormal movements. However, spasticity can be worsened by constraint.

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Glucose-6-phosphate dehydrogenase deficiency is an X-linked recessive hereditary disease characterised by abnormally low levels of glucose-6-phosphate dehydrogenase (abbreviated G6PD or G6PDH), a metabolic enzyme involved in the pentose phosphate pathway, especially important in red blood cell metabolism. Individuals with the disease may exhibit nonimmune hemolytic anemia in response to a number of causes, most commonly infection or exposure to certain medications or chemicals. G6PD deficiency is closely linked to favism, a disorder characterized by a hemolytic reaction to consumption of broad beans, with a name derived from the Italian name of the broad bean (fava). The name favism is sometimes used to refer to the enzyme deficiency as a whole, although this is misleading as not all people with G6PD deficiency will react to consumption of broad beans.

G6PD deficiency is the most common human enzyme defect.[1]

Most individuals with G6PD deficiency are asymptomatic.

Symptomatic patients are almost exclusively male, due to the X-linked pattern of inheritance, but female carriers can be clinically affected due to lyonization, where random inactivation of an X-chromosome in certain cells creates a population of G6PD-deficient red blood cells coexisting with normal red cells. Abnormal red blood cell breakdown (hemolysis) in G6PD deficiency can manifest in a number of ways:

Favism may be formally defined as a haemolytic response to the consumption of broad beans. All individuals with favism show G6PD deficiency. However, not all individuals with G6PD deficiency show favism. For example, in a small study of 757 Saudi men, more than 42% showed G6PD deficiency, but none reported symptoms of favism, despite fava in the diet.[2] Favism is known to be more prevalent in infants and children, and G6PD genetic variant can influence chemical sensitivity. Other than this, the specifics of the chemical relationship between favism and G6PD are not well understood.

Many substances are potentially harmful to people with G6PD deficiency, although many will not produce symptoms unless taken in high doses. Antimalarial drugs that can cause acute haemolysis in people with G6PD deficiency include primaquine, pamaquine and chloroquine. There is evidence that other antimalarials may also exacerbate G6PD deficiency, but only at higher doses. Sulfonamides (such as sulfanilamide, sulfamethoxazole and mafenide), thiazolesulfone, methylene blue and naphthalene should also be avoided by people with G6PD deficiency, as should certain analgesics (such as aspirin, phenazopyridine and acetanilide) and a few non-sulfa antibiotics (nalidixic acid, nitrofurantoin, and furazolidone).[3][1][4] Henna has been known to cause haemolytic crisis in G6PD-deficient infants.[5]

Aspirin is now considered safe in therapeutic doses.[citation needed]

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Glomerulonephritis, also known as glomerular nephritis, abbreviated GN, is a renal disease characterized by inflammation of the glomeruli, or small blood vessels in the kidneys.[1] It may present with isolated hematuria and/or proteinuria (blood resp. protein in the urine); or as a nephrotic syndrome, a nephritic syndrome, acute renal failure, or chronic renal failure. They are categorised into several different pathological patterns, which are broadly grouped into non-proliferative or proliferative types. Diagnosing the pattern of GN is important because the outcome and treatment differs in different types. Primary causes are ones which are intrinsic to the kidney, whilst secondary causes are associated with certain infections (bacterial, viral or parasitic pathogens), drugs, systemic disorders (SLE, vasculitis) or cancers.

Thin basement membrane disease is an autosomal dominant inherited disease characterised by thin glomerular basement membranes on electron microscopy. It is a benign condition that causes persistent microscopic haematuria.

This is characterised by low numbers of cells (lack of hypercellularity) in the glomeruli. They usually cause nephrotic syndrome. This includes the following types:

This form of GN causes 80% of nephrotic syndrome in children, but only 20% in adults. As the name indicates, there are no changes visible on simple light microscopy, but on electron microscopy there is fusion of podocytes (supportive cells in the glomerulus). Immunohistochemistry staining is negative. Treatment consists of supportive care for the massive fluid accumulation in the patients body (= oedema) and as well as steroids to halt the disease process (typically Prednisone 1 mg/kg). Over 90% of children respond well to steroids, being essentially cured after 3 months of treatment. Adults have a lower response rate (80%). Failure to respond to steroids (‘steroid resistant’) or return of the disease when steroids are stopped (‘steroid dependent’) may require cytotoxic therapy (such as cyclosporin) which is associated with many side-effects.

FSGS may be primary or secondary to reflux nephropathy, Alport syndrome, heroin abuse or HIV. FSGS presents as a nephrotic syndrome with varying degrees of impaired renal function (seen as a rising serum creatinine, hypertension). As the name suggests, only certain foci of glomeruli within the kidney are affected, and then only a segment of an individual glomerulus. The pathological lesion is sclerosis (fibrosis) within the glomerulus and hyalinisation of the feeding arterioles, but no increase in the number of cells (hence non-proliferative). The hyaline is an amorphous material, pink, homogeneous, resulting from combination of plasma proteins, increased mesangial matrix and collagen. Staining for antibodies and complement is essentially negative. Steroids are often tried but not shown to be effective. 50% of people with FSGS continue to have progressive deterioration of kidney function, ending in renal failure.

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