Diseases

Myopathy- desmin storage

A very rare neuromuscular disorder involving the buildup of a certain protein called desmin in various muscles. The severity and rate of progression of the disorder is variable.

Myopathy- limb-girdle- with bone fragility

A rare inherited disorder characterized by easy bone fracturing, poor healing of fractures and progressive weakness of the limb-girdle muscles. The fractures tend to occur before the muscle problems. The slow-healing fractures sometimes resulted in osteomyelitis and limb amputation .

Myopathy- McArdle type

McArdle's disease is caused by deficiency of the muscle-specific isoform of phophorylase enzyme. The enzyme splits glucose-1-phosphate from glycogen to fuel the glycolytic pathway needed for muscle activity. McArdle's disease, although being the commonest form of glycogenosis affecting skeletal muscle, is a rare disease. The disease is typically manifested in childhood/adolescence by exercise intolerance, muscle cramps/pain with the classic "second wind" phenomenon (improvement of symptoms after a short period of slowing down or rest). McArdle's disease with late-onset presentation is very rare and clinically more variable in its presentation than the early onset disorder. The disease may escape clinical diagnosis until progressive or persistent muscle weakness or atrophy occurs at advanced age. We report an atypical case of McArdle's disease diagnosed at the age of 65 years in a patient presenting with progressive fixed proximal muscle weakness with no previous history of episodic muscle dysfunction and discuss the clinical-pathological aspects of the disease

Myopathy- tubular aggregate

A muscle condition characterized by aggregates of tubular structures in muscle tissue which can cause muscle problems such as camps and pain after exertion.

Myopathy- X-linked- with excessive autophagy

An inherited muscle disease characterized by very slow-progressing muscle weakness. Because the condition is X-linked, females may be asymptomatic or display only mild symptoms whereas males have display the complete extent of the symptoms

Myopia 6

eyesight abnormality resulting from the eye's faulty refractive ability; distant objects appear blurred.

Myopia- infantile severe

A severe infantile form of myopia (nearsightedness). The vision problem is occurs at birth or in the first few months of life.

Myositis ossificans

Myositis ossificans is the formation of bone in an area bruised by injury. This usually occurs in the arm or thigh. Myositis ossificans develops in 10% to 20% of thigh contusions. Myositis means inflammation of muscle, and ossificans means bone. A contusion to the arm or thigh causes bleeding, and a clot of blood (hematoma) forms, usually within the muscle. This hematoma then may become bone.

Myositis ossificans post-traumatic

A calcified mass that can occur in soft tissue or muscle following a trauma to the area. The trauma may result from such things as mechanical injury or tendonitis. The symptoms are determined by the location and size of the lesion.

Myostatin-related muscle hypertrophy

Myostatin-related muscle hypertrophy is a rare condition characterized by reduced body fat and increased muscle size. Affected individuals have up to twice the usual amount of muscle mass in their bodies. They also tend to have increased muscle strength. Myostatin-related muscle hypertrophy is not known to cause any medical problems, and affected individuals are intellectually normal.

Myotilinopathy

Myotilinopathy is one of the intermediate filament human disorders associated with mutations in the myotilin gene (MYOT). Myolinopathies include autosomal dominant limb girdle muscular dystrophy type 1A (LGMD1A) and a subgroup of myofibrillar myopathy (MFM) associated with myotilin mutations (MFM/MYOT).

Myotonia atrophica

Myotonic dystrophy is an inherited disorder in which the muscles contract but have decreasing power to relax. With this condition, the muscles also become weak and waste away. (Source: Genes and Disease by the National Center for Biotechnology)

Myotonia congenita

Myotonia congenita is a disorder that affects muscles used for movement (skeletal muscles). Beginning in childhood, people with this condition experience bouts of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally. Although myotonia can affect any skeletal muscles, including muscles of the face and tongue, it occurs most often in the legs. Myotonia causes muscle stiffness that can interfere with movement. In some people the stiffness is very mild, while in other cases it may be severe enough to interfere with walking, running, and other activities of daily life. These muscle problems are particularly noticeable during movement following a period of rest. Many affected individuals find that repeated movements can temporarily alleviate their muscle stiffness, a phenomenon known as the warm-up effect.

The two major types of myotonia congenita are known as Thomsen disease and Becker disease. These conditions are distinguished by the severity of their symptoms and their patterns of inheritance. Becker disease usually appears later in childhood than Thomsen disease and causes more severe muscle stiffness, particularly in males. People with Becker disease often experience temporary attacks of muscle weakness, particularly in the arms and hands, brought on by movement after periods of rest. They may also develop mild, permanent muscle weakness over time. This muscle weakness is not seen in people with Thomsen disease.

 

Myotonic Dystrophy 1

Myotonic Dystorphy 1 is a rare genetic disorder characterized by myotonia, muscle atrophy, cataracts and hypogonadism

Myotonic Dystrophy 2

Myotonic Dystorphy 2 is an inherited disorder characterized by progressive muscle weakness and wasting as well as eye defects, heart abnormalities and other anomalies. The severity of the condition is greatly variable. There are two type of myotonic dystrophy with type 1 being more severe than type 2. Type 2 also tends to affect muscle closer to the trunk e.g. upper leg and shoulders

Myotubular myopathy

Myotubular myopathy (also called Centronuclear myopathy) is a group of congenital myopathies where cell nuclei are abnormally located in skeletal muscle cells. In Myotubular myopathy the nuclei are located at a position in the center of the cell, instead of their normal location at the periphery.

Symptoms of Myotubular myopathy include severe hypotonia, hypoxia-requiring breathing assistance, and scaphocephaly. Among centronuclear myopathies, the X-linked myotubular myopathy form typically presents at birth, and is thus considered a congenital myopathy. However, some centronuclear myopathies may present later in life.

Myxedema

Myxedema (British English: myxoedema) is a skin and tissue disorder usually due to severe prolonged hypothyroidism. Hypothyroidism can be caused by atrophic disease, Hashimoto's thyroiditis, surgical removal of the thyroid, and rarer conditions. Partial forms of myxedema, especially of the lower legs (called pretibial myxedema), occasionally occur in adults with Graves' disease, a cause of hyperthyroidism; or also Hashimoto's thyroiditis without severe hypothyroidism.

Myxoid liposarcoma

A form of malignant tumor. It is a subtype of liposarcoma and is frequently located in the deeper layers of soft tissue of the arms and legs such as the thigh.

Myxoma-spotty pigmentation-endocrine overactivity

A very rare syndrome characterized by spotty pigmentation on the skin and the development of multiple benign tumors (myxoma) that can occur just about anywhere in the body but mainly in the skin, breast and heart and endocrine glands such as the thyroid and pituitary gland. The symptoms are highly variable depending on the location, size and number of tumors. Endocrine gland tumors can affect hormone production and hence result in a range of symptoms.

Myxomatous peritonitis

X-linked myxomatous valvular disease is characterized by mitral valve dystrophy frequently associated with degeneration of the aortic valves affecting males and, to a lower severity, females. The first localization of a gene for myxomatous valvular diseases is the first step for the subclassification of these diseases. Abbreviations and Acronyms AML = anterior mitral leaflet F.VIII = antihemophilic factor VIII LAA = left atrial area LVOTD = left ventricular outflow tract diameter MVD = myxomatous valve dystrophies PML = posterior mitral leaflet RJA = regurgitating jet area Valvular disease with myxomatous degeneration forms a complex group of disorders. Common histological features and a clinical continuum from isolated nonsyndromic valvular defects (e.g., idiopathic mitral valve prolapse) to multivalvular diseases and syndromic disorders (e.g., Marfan syndrome) make it difficult to subclassify these heterogeneous and complex pathologies. Defects in fibrillin (1) and collagen genes (2) have already been identified in syndromic valvular disease. In other valvular dystrophies with myxomatous degeneration, identification of genetic defects would appear to be an essential step in their subclassification

Myxozoa

A group of parasites that infect fish

N-acetyl glucosamine 6-sulfate sulfatase deficiency

N-acetyl glucosamine 6-sulfate sulfatase is a lysosomal enzyme found in all cells. It is encoded by the GNS gene. It is involved in the catabolism of heparin, heparan sulphate, and keratan sulphate. Deficiency of this enzyme results in the accumulation of complex carbohydrates in the body's cells and tissues and in the cellular organelles, the lysosomes. These complex carbohydrates, also known as mucopolysaccharides or glycosaminoglycans (GAGs), serve as the building blocks for connective tissues in the body.

Deficiency of the N-acetyl glucosamine 6-sulfate sulfatase is called mucopolysaccharidosis type IIID (Sanfilippo D syndrome), and was first described at the American Pediatric Society Annual Meeting by pediatrician, Sylvester Sanfilippo, in 1963. The approximate incidence of Sanfilippo D syndrome is about 1:1,000,000.

N-acetyl-alpha-D-galactosaminidase

N-acetyl-alpha-D-galactosaminidase: A very rare enzyme deficiency (N-acetyl-alpha-D-galactosaminidase) which can occur in three forms: type I (infantile-onset neuroaxonal dystrophy), type II or Kanzaki disease (adult-onset) and type III (mild or moderate form)

N-acetylglutamate synthetase deficiency

N-acetylglutamate synthase (NAGS) deficiency is type of urea cycle disorder leading to hyperammonaemia. It is an inherited disorder that causes ammonia to accumulate in the blood. The product of NAGS, N-acetylglutamate (NAG), is an allosteric activator of carbamylphosphate synthetase I (CPSI), the enzyme catalysing the first step in ureagenesis. In patients with NAGS deficiency, NAG is not available in sufficient quantities, or is not present at all and, hence, the body levels of ammonia increase.

Ammonia, which is formed when proteins and amino acids are broken down in the body, is toxic if the levels become too high. The nervous system is especially sensitive to the effects of excess ammonia. The disorder is very rare and the prevalence is unknown. Only a handful of cases have been described worldwide. 

Nablus mask-like facial syndrome

Nablus mask-like facial syndrome is a rare microdeletion syndrome, characterized by a mask-like facial appearance.

In 2000, Teebi, was the first to report on a 4 years old boy affected with NMFLS. Since then, a handful of additional patients have been reported.

NADH cytochrome B5 reductase deficiency

Methemoglobinemia due to NADH-cytochrome b5 reductase deficiency (recessive congenital methemoglobinemia, RCM) is an autosomal recessive disorder characterized clinically by decreased oxygen carrying capacity of the blood, with resultant cyanosis and hypoxia.

There are 2 types of RCM. In type I, the defect affects the soluble form of the enzyme, is restricted to red blood cells, and causes well-tolerated methemoglobinemia. In type II, the defect affects both the soluble and microsomal forms of the enzyme and is thus generalized, affecting red cells, leukocytes, and all body tissues. Type II methemoglobinemia is associated with mental deficiency and other neurologic symptoms. The neurologic symptoms may be related to the major role played by the cytochrome b5 system in the desaturation of fatty acids. 

Naegeli syndrome

Naegeli syndrome is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Naegeli syndrome, or a subtype of Naegeli syndrome, affects less than 200,000 people in the US population.