Riboflavin deficiency, symptoms

Riboflavin (vitamin B2) is found in liver, milk, meat, green vegetables, cereals and mushrooms. It is active in the form of two coenzymes, flavin mononucleotide and flavin adenine dinucleotide. As a coenzyme for proton transfer in the respiratory chain it is indispensable for energy-release from carbohydrates, lipids and proteins. Riboflavin deficiency only occurs in combination with deficiencies of other members of the vitamin B family. The symptoms of such deficiency consist of angular stomatitis, lesions of the cornea, dermatoses and normochromic normocytic anaemia. 

Riboflavin deficiency is not associated with a major human disease, although it frequently accompanies other vitamin deficiencies. Deficiency symptoms include dermatitis, cheilosis (fissuring at the corners of the mouth), and glossitis (the tongue appearing smooth and purplish). 

A-33 Symptoms associated with riboflavin deficiency include ... 

Severe riboflavin deficiency is known as ariboflavinosis. Its major symptoms include cheilosis,. seborrheic dermatitis, and vascularization of the cornea. Ariboflavinosis occurs in chronic alcoholism in combination with other vitamin deficiencies. It has also resulted from phenothiazine, tricyclic antidepressant, and probenecid therapy. Riboflavin has no pharmacological action and is relatively nontoxic. The only approved indication is in the treatment and prevention of ariboflavinosis. 

Vitamers are chemically similar substances that have a qualitatively similar vitamin activity. Thus, vitamin D refers to ergocalciferol (Da) and cholecalciferol (D3) and sometimes to their 25-hydroxy- and 1,25-dihydroxy derivatives (Chapter 37). Similarly, pyridoxine (pyri-doxol), pyridoxal, and pyridoxamine are vitamin Be vitamers, riboflavin is the active form of vitamin Ba and cobalamin is vitamin Bia- The members of a particular vitamin family are functionally interchangeable and protect against deficiency symptoms for that vitamin. A vitamin and its corresponding deficiency disease are related as follows ... 

An example of the difference between the AI and the EAR is provided by riboflavin. Very few data exist on the nutrient requirements of very young infants. However, human milk is the sole recommended food for the first 4 to 6 months, so the AI of the vitamin riboflavin for this life stage group is based on the amount in breast milk consumed by healthy full-term infants. Conversely, the riboflavin EAR for adults is based on a number of studies in humans relating dietary intake of riboflavin to biochemical markers of riboflavin status and development of clinical deficiency symptoms. 

The vitamin is synthesised in the rumen and deficiencies in animals with functional rumens are unlikely to occur. However, riboflavin deficiencies have been demonstrated in young calves and lambs. Symptoms include loss of appetite, diarrhoea and lesions in the corners of the mouth. 

Riboflavin deficiency will lead to accumulation of amino acids. A specific deficiency symptom is the decrease of glutathione reductase activity in red blood cells. 

The daily requirement is given in Table 6.3. Deficiency symptoms are rarely observed with a normal diet and, since the riboflavin pool in the body is very stable, even in a deficient diet it is not depleted by more than 30-50%. The riboflavin content of urine is an indicator of riboflavin supply levels. Values above 80pg riboflavin/g creatinine are normal 27-79 pg/g are low and less than 27 pg/g strongly suggests a vitamin-deficient diet. Glutathione reductase activity assay can provide similar information. 

Tissues that receive the greatest exposure to light, that is, skin and ocular tissue, manifest the earliest clinical symptoms of a riboflavin deficiency. These include pellagralike symptoms pellagra sine pellagra) lesions around the comer... 

An infection of the skin at the angles of the mouth, characterized by the epithelium protruding into ridges, giving the appearance of fissures. This is a symptom of riboflavin deficiency and of other diseases. But it can also be produced by poorly fitting dentures. 

Manifestations of riboflavin deficiency center around the following symptoms ... 

Vitamins, minerals, and electrolytes— Studies have shown that during moderate to severe stresses, more zinc, copper, magnesium, and calcium are lost in the urine. Furthermore, stress results in altered blood levels of vitamins A and C, and of zinc and iron. Also, part of the response to stress includes water and sodium retention, via veisopressin and aldosterone secretion. As for the water-soluble vitamins—thiamin, riboflavin, niacin, pyridoxine (B-6), pantothenic acid, folic acid, and vitamin C stress increases their requirement. However, no dietary recommendations are made for these nutrients for individuals under stressful situations. Still, it seems wise to supply some supplementation before deficiency symptoms appear. 

Many tissues are affected by riboflavin deficiency (aribofla-vinosis). Riboflavin deficiency requires 3-4 months of deprivation to manifest and symptoms include lesions on the lips, inflammation of the tongue, lowered levels of white and red blood cells, excessive sensitivity to pain and vascu-larisation of the cornea. Deficiency also results in decreased conversion of tryptophan into niacin. A test for deficiency is to measure glutathione reductase levels, which are depressed when riboflavin levels are low as are xanthine oxidase levels. There is a link between riboflavin deficiency in pregnancy and the development of pre-eclampsia. However, supplementation with riboflavin in a trial indicated that there was no effect on the prevention of pre-eclampsia. Alcoholics are at increased risk of riboflavin deficiency as... 

In foods vitamin B2 occurs free or combined both as FAD and FMN and complexed with proteins. Riboflavin is widely distributed in foodstnffs, but there are very few rich sources. Only yeast and liver contain more than 2mg/100g. Other good sources are milk, the white of eggs, fish roe, kidney, and leafy vegetables. Since riboflavin is continuously excreted in the urine, deficiency is qnite common when dietary intake is insufficient. The symptoms of deficiency are cracked and red lips, inflammation of the lining of the month and tongue, mouth ulcers, cracks at the comer of the mouth, and sore throat. Overdose of oral intake present low toxicity, probably explained by the limited capacity of the intestinal absorption mechanism [417]. 

Riboflavin vitamin Bf) deficiency results in local seborrheic dermatitis that may be limited to the face and scrotum. Other symptoms of ariboflavinosis include angular stomatitis, cheilitis, and glossitis. Specific ocular... 

The typical Bg avitaminosis is very similar to riboflavine and niacin deficiency and is manifested by eye, mouth, and nose lesions as well as neurological symptoms. 

Branched-chain ketoaciduria (commonly known as Maple Syrup Urine Disease MSUD) is another ailment that may be caused by thiamine deficiency. In MSUD, the oxidative decarboxylation of alpha-keto acids derived from, i.e. valine, isoleucine, and leucine, is blocked due to an inadequate supply of the coenzyme thiamine pyrophosphate (TPP). Clinical symptoms of MSUD include mental and physical retardation. Describe briefly the structure of Riboflavin (Vitamin B-2) and its biochemical role. 

Vitamin B2 (riboflavin) is a constituent of yeast extract and is incorporated into many vitamin preparations. Vitamin B2 deficiency is characterized by symptoms that include an inflamed tongue, dermatitis and a sensation of burning in the feet. In genuine cases of malnutrition, these symptoms will... 

Riboflavin-responsive MADD. Designation for patients suffering from multiple acyl-CoA dehydrogenation deficiency, a rare mitochondrial p-oxidation disease, whose clinical and biochemical symptoms recover upon dietary intake of high-doses of the vitamin riboflavin. 

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