Body fluids malnutrition

Increasingly, the phase angle, which is based on the ratio between Xc and R, is becoming more widely accepted as a marker of nutritional status (5,33-35). Xc, which results from the capacitive properties of cell membranes and tissue interfaces, is usually reduced in malnutrition to a greater extent than R, which is related to the volume of body fluid. Therefore, it is assumed that Xc is an indicator of overall nutritional status and a reflection of the total amount of cell membrane in the body, specifically in the body cell mass. 

The total body water content increases in patients with severe protein malnutrition. The increase involves both the extracellular fluid, in which the water content may rise up to 400 ml/kg compared to 250 ml/kg in normal individuals, and in the intracellular fluid, in which the water content may reach values above 80%, compared to the normal 67% values in normally fed individuals. Fluid accumulation in the extracellular tissues leads to edema. The severity of the edema may be masked somewhat by the loss of body solids and fats. However, in the later stages of the disease, edema becomes obvious. The edema fluid is not distributed uniformly throughout the body of the victim—swelling usually starts in the inferior limbs, probably as a result of gravity and deficient circulation. The back of the hand and the face are frequently swollen. A patient with kwashiorkor— particularly an older patient— may have edema in the lower part of the body and be dehydrated in the upper part. In younger children, this does not occur because the upright position is not maintained constantly and does not play such an important role in the accumulation of fluid in the inferior limbs. The pathogenesis of the edema in protein deficiency is discussed in the section on body fluids. 

Although the sodium content in the body fluid and the tissues varies considerably in children with protein malnutrition, potassium depletion of various degrees of severity is a constant finding in severely malnourished children. Alterations in mineral metabolism observed in malnutrition may result from increased metabolic breakdown with a decrease in available energy sources. 

Bioenergetics Cell Specificity Inborn Errors of Metabolism Malnutrition Calcium and Phosphorus Iron and Bile Pigments Coagulopathies Hormones Body Fluids and Electrolytes... 

While low serum cholesterol levels have been observed in malnourished patients, largely as a result of decreased synthesis of lipoproteins in the liver, hypocholesterolemia occurs later in the course of malnutrition and is therefore not useful as a screening test. PEM usually results in low serum urea nitrogen (BUN), urinary urea, and total nitrogen. Estimation of 24-h urine creatinine excretion is also a valuable biochemical index of muscle mass (when there is no impairment in renal function). The urinary CHI is correlated to lean body mass and anthropometric measurements. In edematous patients, for whom the extracellular fluids contribute to body weight and spuriously high body mass index values, the decreased CHI values are especially useful in diagnosing malnutrition. 

Five million children worldwide die every year from malnutrition. In the UK it is usually precipitated by severe illness, but in developing countries it is more likely to be caused by poor diet. Kwashiorkor is most common in rural Africa and is due to deficiency of both protein and foods providing calories (PEM). It is characterized by painless pitting oedema, skin lesions, muscle wasting and GI infections. The excess fluid retention (oedema) can often mask loss of body tissue. 

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