A rare blood disorder where there are abnormally low levels of neutrophils (type of white blood cell) in the body which impairs the body's ability to fight bacterial infections. There are four main types of the disorder: idiopathic, congenital, autoimmune and cyclical
Acute febrile neutrophilic dermatosis, also termed Sweet syndrome, is a reactive process characterized by the abrupt onset of tender, red-to-purple papules, and nodules that coalesce to form plaques. The plaques usually occur on the upper extremities, face, or neck and are typically accompanied by fever and peripheral neutrophilia. Initially described in 1964 by Robert Sweet, the entity currently recognized as Sweet syndrome ranges from classic Sweet disease, which occurs in young women after a mild respiratory illness, to a more aggressive neutrophilic process, which may be associated with other inflammatory diseases or malignancy. In fact, the lesions may be the first evidence of an underlying disorder and should prompt further investigation. A drug-induced variant due to the administration of various medications has been recognized, and a pregnancy-associated form has also been reported. In general, Sweet syndrome responds dramatically to oral corticosteroids and may improve or resolve with treatment of the underlying condition. Without treatment, the syndrome may persist for weeks or months and then improves without leaving scars. Recurrences are common. In rare cases, crops of lesions reappear and the condition persists indefinitely. Cases associated with malignancy can be bullous or ulcerative and resemble atypical pyoderma gangrenosum. These lesions are often recalcitrant to treatment. The diagnosis of Sweet syndrome is based on both clinical and histopathologic findings. Characteristics that distinguish the lesions of Sweet syndrome from other neutrophilic dermatosis are healing of the lesions without scarring and an absence of vasculitis.
A rare inherited condition involving the presence of dark red, flat patches of skin. The patches can occur anywhere on the body, they vary in size and there is more than one.
Nevo syndrome (medical condition): A genetic disorder characterized by excessive fetal growth, loose joints, kyphosis and impaired speech and motor development
Nevoid basal cell carcinoma syndrome (NBCCS, also known as basal cell carcinoma nevus syndrome, multiple basal cell carcinoma syndrome, Gorlin syndrome, and Gorlin–Goltz syndrome,and BCCNS), is an inherited medical condition involving defects within multiple body systems such as the skin, nervous system, eyes, endocrine system, and bones. People with this syndrome are particularly prone to developing a common and usually non-life-threatening form of non-melanoma skin cancer.
About 10% of people with the condition do not develop basal-cell carcinomas (BCCs). The name Gorlin syndrome refers to researcher Robert J. Gorlin (1923–2006).
First described in 1960, NBCCS is an autosomal dominant condition that can cause unusual facial appearances and a predisposition for basal-cell carcinoma, a type of skin cancer which rarely spreads to other parts of the body. The prevalence is reported to be 1 case per 56,000-164,000 population. Recent work in molecular genetics has shown NBCCS to be caused by mutations in the PTCH (Patched) gene found on chromosome arm 9q. If a child inherits the defective gene from either parent, he or she will have the disorder.
Nevus of ota retinitis pigmentosa: A very rare syndrome characterized by abnormal pigmentation of the eye and the skin surrounding the eye
Nevus sebaceous of Jadassohn: A rare genetic neurocutaneous disorder characterized by epidermal nevi associated with central nervous and skeletal system abnormalities
NGLY1 deficiency (or N-glycanase deficiency) is an extremely rare genetic disorder of the endoplasmic reticulum. It falls within the family of Congenital Disorders of Glycosylation (CDG). In this disorder, the cells of the body cannot synthesize the enzyme N-glycanase. N-glycanase 1 (encoded by the gene NGLY1) is responsible for cleaving N-linked glycans from misfolded glycoproteins, so that the body can recycle them. Lacking N-glycanase leaves the body with an impaired capacity to recycle misfolded glycoproteins, which appear to accumulate in the cells of patients, and which is associated with neurological dysfunction, abnormal tear production, and liver disease. The majority of patients detected to date carry a specific nonsense mutation that appears to be associated with severe disease. The phenotypic spectrum is likely to enlarge as cases with a broader range of mutations are detected.
N-glycanase deficiency is recessive: when parents are carriers, they have a 25% chance of producing a child with the disorder for each pregnancy.
Nguyen syndrome: A rare disorder characterized by low blood cholesterol, mental retardation and various congenital anomalies
Nicolaides–Baraitser syndrome (NCBRS) is a rare genetic condition caused by de novo missense mutations in the SMARCA2 gene and has only been reported in less than 100 cases worldwide. NCBRS is a distinct condition and well recognizable once the symptoms have been identified.
Niemann–Pick disease is a group of inherited severe metabolic disorders in which sphingomyelin accumulates in lysosomes in cells. The lysosomes normally transport material through and out of the cell.
The prognosis is individual but the severe form is fatal in toddlerhood and the milder forms may even in some cases have a normal lifespan.
This disease involves dysfunctional metabolism of sphingolipids, which are fats found in cell membranes, so it is a kind of sphingolipidosis. Sphingolipidoses, in turn, are included in the larger family of lysosomal storage diseases.
Niemann-Pick disease (NPC) is an inherited metabolic disorder where lipids are not able to be metabolized adequately and hence build up and cause damage in various parts of the body such as the spleen, liver, lungs, bone marrow and brain. The different types of the disease are due to different genetic mutations.
There are four most commonly recognized forms of the disease: Types A, B, C, and D. Types A and B are also called Type I. Types C and D are also known as Type II.
Type C is a juvenile or subacute form of the condition which usually starts during childhood and survival into adulthood is possible.
Niemann-Pick disease is an inherited metabolic disorder where lipids are not able to be metabolized adequately and hence build up and cause damage in various parts of the body such as the spleen, liver, lungs, bone marrow and brain.
Type D Niemann-Pick involves a defect that interferes with the movement of cholesterol between brain cells. It is now thought to be a variant of type C. This type of Niemann-Pick disease has only been found in the French Canadian population of Yarmouth County, Nova Scotia.
Symptoms, diagnosis, prevention and treatment are the same as with Type C. Please see our Niemann-Pick Disease page for more Information.
Nievergelt syndrome: A rare inherited bone disease which causes abnormalities in the lower leg and lower arm bones as well as dwarfism and digit anomalies
Night blindness - skeletal anomalies - unusual facies: A very rare syndrome characterized mainly by night blindness, a distinctive face and skeletal abnormalities
Night blindness, congenital stationary, type 1A: A rare X-linked disorder of the retina that involves the rods of the eyes. A reduced sharpness of vision and night blindness are usually the only symptoms. The non-progressive disorder is linked to a defect at chromosome Xp11.4 and occurs only in males though females may be carriers
Nijmegen breakage syndrome (NBS) is a rare autosomal recessive condition of chromosomal instability that is clinically characterized by microcephaly, a distinct facial appearance, short stature, immunodeficiency, radiation sensitivity, and a strong predisposition to lymphoid malignancy. Mutations in the NBS1 gene located in band 8q21 are responsible for NBS. NBS is identified as entries 251260 in and 602667 in Online Mendelian Inheritance in Man. In 1981, Weemaes et al1 first delineated the syndrome in 2 siblings with microcephaly, short stature, skin pigmentation abnormalities, mental retardation, immunologic defects, and a high prevalence of chromosome 7 and/or chromosome 14 rearrangements in cultured lymphocytes. In 1985, Seemanova et al2 described a group of patients with an apparently new genetic disorder characterized by microcephaly with normal intelligence, cellular and humoral immune defects, and a striking predisposition to lymphoreticular malignancies. These cases were subsequently studied and found to fit into the category of NBS. Further investigations revealed that in vitro cells derived from patients with NBS display characteristic abnormalities similar to those observed in ataxia-telangiectasia (A-T), including spontaneous chromosomal instability, sensitivity to ionizing radiation (IR), and radioresistant DNA synthesis (RDS). However, aside from immune deficiency and a predisposition for malignancies (particularly those of lymphoid origin), the clinical manifestations are distinct. Consequently, NBS has long been considered a variant of A-T. In 1998, on the basis of cellular phenotypes and the results of somatic cell complementation studies suggesting genetic heterogeneity, Jaspers et al proposed the term A-T variants for diseases in this group of patients. The 2 distinct groups were designated as A-T variant 1 (V1) for NBS and A-T variant 2 (V2) for Berlin breakage syndrome. Linkage studies allowed the exclusion of the gene responsible for NBS from the A-T locus on band 11q23 and from the translocation breakpoints in a Polish patient. When 2 independent groups of researchers finally mapped the gene to band 8q21 and isolated it in 1998, mutations in the single NBS1 gene were found to account for both A-T complementation groups V1 and V2.
Nipah virus encephalitis: Inflammation of the brain caused by the Nipah virus which can infect pigs and humans so transmission usually occurs through contact with pigs.
Nivelon-Nivelon-Mabille syndrome: A very rare syndrome characterized mainly by severe dwarfism, abnormal bone development and central nervous system and eye problems
Noble-Bass-Sherman syndrome: A very rare syndrome characterized by various eye anomalies
Nocardiosis is an infection caused by bacteria (Nocardia) which live in the soil. If inhaled, the bacteria may cause pneumonia, which can lead to blood poisoning (sepsis) and the spread of nocardiosis to other organs of the body. This is called disseminated nocardiosis. People with compromised immune systems, such as people with cancer or those taking steroids or immunosuppressive medications, are at risk for disseminated nocardiosis. Nocardia may also infect the skin through a cut, puncture wound, or scratch that occurs while working outdoors or gardening. The skin infections, which may take different forms, are called cutaneous nocardiosis. Occupational exposure to soil, as in field work, landscaping, and farming, increases the risk of contracting cutaneous nocardiosis
Nodular melanoma (NM) is the most aggressive form of melanoma. It grows in vertical direction from the outset and grows very fast (months). Nodular melanoma has no known precursor. It is a small black, or if amelanotic, pink nodule that simply enlarges. The lesions tend to bleed. The microscopic hallmarks are:
• Dome-shaped at low power
• Epidermis thin or normal
• Dermal nodule of melanocytes with a “pushing” growth pattern
• No "radial growth phase"
Noma (from Greek numein: to devour) also known as cancrum oris or gangrenous stomatitis, is a gangrenous disease leading to tissue destruction of the face, especially the mouth and cheek
Non alcoholic steatohepatitis (NASH) is liver inflammation caused by a buildup of fat in the liver. NASH is part of a group of liver diseases, known as nonalcoholic fatty liver disease, in which fat builds up in the liver and sometimes causes liver damage that gets worse over time (progressive liver damage). Although the cause is not known, NASH seems to be related to certain other conditions, including obesity, high cholesterol and triglycerides, and diabetes. Treatment for NASH involves controlling those underlying diseases
Non functioning pancreatic endocrine tumor: A tumor of the pancreas that does not result in an increased hormone production but can cause symptoms when the tumor becomes big enough to push against other structures. The tumor may be malignant or benign.
Non 24 hour sleep wake disorder refers to a steady pattern of one- to two-hour delays in sleep onset and wake times in people with normal living conditions. This occurs because the period of the person's sleep-wake cycle is longer than 24 hours. The condition most commonly affects people who are blind, due to an impaired sense of light-dark cycles. Non 24 hour sleep wake disorder can also affect sighted people. The cause of the disorder in these cases is incompletely understood, but studies suggest melatonin levels play a role.
Apart from the social stress or depression that living with this disorder may cause, the disorder itself is not considered harmful. The actual quality of sleep, and more importantly deep sleep, is equal or in many cases better, than those without the disorder.
A rare chronic form of sleep disorder involving a disturbance of the circadian rhythm. Patients have a consistent one or two hour delay in the time the go to sleep as well as the time they wake up so their sleep pattern doesn't fit into the 24 hour cycle. Thus, the sleep cycle changes every day which can be very disruptive. It has most often been reported in blind people. More detailed information about the symptoms, causes, and treatments of Hypernycthemeral syndrome is available below.
Source: Wrong Diagnosis
Nondystrophic myotonia: A group of rare diseases characterized by a muscle disorder where the voluntary muscles are slow to relax after movement. The problem occurs intermittently and can sometimes be painful but no muscle wasting occurs