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Salk Scientists Find Potential Therapeutic Target for Cushing's Disease

Salk Scientists Find Potential Therapeutic Target for Cushing’s Disease

The protein, called TR4 (testicular orphan nuclear receptor 4), is one of the human body’s 48 nuclear receptors, a class of proteins found in cells that are responsible for sensing hormones and, in response, regulating the expression of specific genes. Using a genome scan, the Salk team discovered that TR4 regulates a gene that produces adrenocorticotropic hormone (ACTH), which is overproduced by pituitary tumors in Cushing’s disease (CD). The findings were published in the May 6 early online edition of Proceedings of the National Academy of Sciences.



The name porphyria is taken from the Greek root for purple (porphyra). Porphyrias are a group of 8 inherited or acquired disorders of heme biosynthesis. A deficiency in any of the 8 enzymes in the biosynthetic pathway can result in the accumulation and excretion of intermediary metabolites. Patients generally present with either neurovisceral (acute) or cutaneous symptoms but sometimes they may have mixed symptoms. One of the earliest descriptions of porphyria was made by B.J. Stokvis, MD, in 1889. In 1930, the German chemist Hans Fischer described porphyrins as The compounds which make grass green and blood red. In 1937, Jan Gosata Walenstrom coined the term porphyria he published research identifying one type of porphyria, acute intermittent porphyria (AIP). By 1960, all 8 types of porphyria had been described, as well as environmental factors that affect the course of the disease.  Porphyria research in the 1980s and 1990s identified the molecular defects in each type.

Carnitine Palmitoyltransferase

Carnitine Palmitoyltransferase (CPT), CPT-II Deficiency

A physically fit, 39-year-old Norwegian woman arrives at the hospital complaining of generalized muscle weakness. She informs the resident that her symptoms began 3 days earlier after experiencing flu-like symptoms and a sore throat. Her weakness has progressed to the point where she needs help walking and she indicates that her arms feel heavy and tired. She has a dull pain in her lower back, chest, and proximal muscles of both her arms and legs when she moves. She does not have any abdominal or urinary issues, sensory disturbances, or difficulties breathing or coughing. There is no history of drug or alcohol abuse; she doesn’t smoke or take prescription medications. She can’t recall having any insect bites and occasionally travels in Europe for business.

Congenital Genu Recurvatum

Congenital Genu Recurvatum

Genu recurvatum loosely translates as backward-bending knee. It is also known as congenital dislocation of the knee (CDK) or congenital dislocation of the patella (CDP), and sometimes as congenital hyperextension. CDK is a rare condition with an incidence rate of approximately 1 per 100,000 live births. It is characterized by congenital hyperextension of the knee and marked limitation of flexion. Patients with this condition present with a patella that is dislocated laterally, permanently, and irreducibly. However, there is some disagreement with this description. Some suggest obligatory patella dislocation is a separate condition where the dislocation is hypoplastic to start and becomes fixed into the lateral position as the child grows. Some physicians believe this condition should be renamed developmental dysplasia and dislocation disorder (DDDP) to more accurately reflect it as a wide-spectrum disorder.

Primary Amoebic Meningoencephalitis

Primary Amoebic Meningoencephalitis (PAM)

There is no escaping the fact that our world is teeming with microorganisms. They share our world and are all around us. They live on, as well as inside, everyone. Some are beneficial. In industry, they are used to help break down hazardous waste in the development of food, biofuels, biotechnologies, and pharmaceuticals. Human flora and fauna contribute greatly to an individuals overall heath. They help boost our immune system and are key players in the production of biotin and vitamin K. It has even been suggested that mitochondria, our cellular powerhouse, are derived from a symbiotic relationship between eukaryotic cells (cells with a nucleus) and ancient bacteria that could produce energy through aerobic respiration.

Fibrodysplasia Ossificans Progressiva

Fibrodysplasia Ossificans Progressiva

Fibrodysplasia Ossificans Progressiva (FOP) is one of the rarest diseases in the world. Patients with FOP are born with characteristic malformations of the great toes (short and bent, sometimes turning inward), but otherwise these children appear normal.

Wilson's Disease

Wilson’s Disease

At age 24, a young woman (let’s call her Ann) was healthy, vibrant, and carefree. After her 25th birthday, Ann began to experience upper limb tremors. Within 4 months, the tremors progressed to all of Ann’s limbs, followed by bouts of mania. Due to the neuropsychological presentations, a psychiatrist prescribed Ann haloperidol, chlorpromazine, and propranolol to treat the mania. A further regimen of levodopa and carbidopa was prescribed by a neurophysician to treat the atypical Parkinson’s.



In genetics, a chimera is an individual with 2 or more distinct, unrelated genetic lineages (ie, 46XX/46XX, 46XX/46XY, or 46XY/46XY). This condition is not to be confused with germline mosaicism, in which a mutation occurs during mitosis, altering part of a genetic line (aneuploidy). In mosaics, typically transcription errors result in a chromosome that may be either duplicated or deleted. The mutated cell is further copied, appearing separate from other cells (46XX/47XX or 46XY/47XY) but in fact, a single lineage exists. An individual with germline mosaicism shouldn’t have any related health issues since it is not a systemic mutation. An example of mosaicism where a systemic mutation exists is Trisomy 21, or Down’s syndrome, where a duplicating error occurs on chromosome 21 affecting all or nearly every cell.

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