Understanding Fasting Hypoglycaemia Through Case Study

Answers to Questions

The nature of the girl’s hypoglycaemia is fasting hypoglycaemia. Fasting glycemia occurs when a person is fasting for around 8 hours or longer. During this time the blood glucose level decreases to a level much lower than the normal range of 70 milligrams per decilitre. It is a condition of the body in which the body is unable to maintain sufficient level of blood glucose after certain a fasting (Yale, Paty & Senior, 2018). Fasting hypoglycaemia can occur due to use of some specific medicine or due to some defect in metabolic pathway which leads to the formation of glucose or conversion of stored glycogen to glucose during the period of fasting.

 Fasting for a long period of time causes a reduction of the source of glucose in the blood and is also associated with the reduction of the insulin level in the blood (Kondo et al., 2019). As a result of this, the reduction of insulin level mobilises the decomposition of fat in the body. However, during search prolong time of fasting the body produces excessive amount of ketone bodies which includes acetone, beta hydroxybutyric acid and acetoacetic acid. As a result of this, mobilization of fat decomposition causes metabolic acidosis during which levels of the reserve alkaloids have exceeded the normal range in the body. In association with the production of ketone bodies fasting causes a reduction in the level of stress hormone in the body which includes catecholamines and cor-tisol, however higher level of stress when combined with prolonged starvation causes severe metabolic acidosis in the body.

In case of this girl, 12-hour starvation have late to the condition of metabolic acidosis in her body.

The metabolic pathway that is likely to be compromised is the glycogenolysis or glycogen breakdown pathway. Glycogenolysis is the process by which the glycogen which is the primary carbohydrate that is stored in the liver as well as in the muscles of the animals is broken down to form glucose (Jayan & Vadakkan, 2019). This glucose produced from glycogen provides immediate energy to the body and maintains the level of glucose in the blood during prolonged fasting. Since the girl is suffering from fasting hypoglycaemia, it can be said that the glycogenolysis process is more likely to be compromised due to which the blood sugar level is decreased during the 12-hour fasting.

In Glucagon experiment it is observed that after an overnight fasting for 12 hours, when intramuscular dose of one milligram of glucagon failed to rise the plasma glucose concentration in the girl. However, as the same dose was administered 2 hours after the meal, plasma glucose level in her blood rose by around 3 mmol/L in 30 minutes. This indicates that during the 12-hour fasting, the glycogen stored in the liver and the muscles were utilised by glycogenolysis pathway to provide glucose in the bloodstream which would help to maintain the blood sugar level as well as meet the energy requirement of the body. As a result of this, the glucagon dose failed to raise the glucose level as the storage of glycogen in liver was exhausted (Ishibashi et al., 2020). However, after the meal the glycogen storage was field with the newly synthesized glycogen 2 which on administration of glucagon dose could increase the blood sugar level within a short period of time.

Answer 1a

The glucose tolerance test that was performed indicates that the girl is suffering from fasting hypoglycaemia. This is because with the increase a fasting time, the level of glucose is drastically reduced in the blood pausing a condition of hypoglycaemia in the girl (Eyth, Basit & Smith, 2020).

Galactose challenge test in the girl provided a result which showed that the level of collectors in the blood do not drastically fall as that of the glucose, which indicates that glucose is being used as the primary source of energy in the body (Saavedra, Aguirre & Gentina, 2020). The figure indicated that the libre is capable of converting galactose into glycogen.

After the challenge dose of fructose, the body might produce a smaller rise of the plasma glucose concentration post prandial. This is because fructose does not raise the blood glucose level accurately because it has lower glycaemic index as compared to other carbohydrates (Hammer et al., 2018). That is why it is usually used as an energy source for the diabetic patient for its aid glycaemic control in the body.

When fructose is accumulated in the blood it results from the inhibition of some enzymes which includes phosphorylase, fructose 1-.6 bisphosphate aldolase and fructokinase (Johnson et al., 2020). As a result of this the glycogenolysis and gluconeogenesis pathway add disrupted which leads to the reduction of formation of glucose in the body and causes severe hypoglycaemia. That is why after challenge dose of fructose severe hypoglycaemia was induced in the girl.

That liver tissue biopsy indicated that the glycogenesis pathway it taking place properly in the liver which resulted from the presence of normal levels of glycogen in it.

The presence of fat vacuoles in the liver indicates that the girl is suffering from fatty liver disease which enlarged the liver cells (Dauriz et al., 2019).

The enzyme which is defective in figure 5 is estimated to be phosphoenolpyruvate carboxylase which converts oxaloacetate into phosphoenolpyruvate.

This is due to the fact that due to defective phosphoenolpyruvate carboxylase which converts oxaloacetate into phosphor enol pyruvate, metabolic acidosis was observed in the patient (Liu et al., 2021). Defective phosphoenolpyruvate carboxylase enzyme causes the accumulation of lactic acid along with other toxic compounds in the blood which increases the amount of acid while decreasing the pH level of the blood.

Laboratory studies would help for definitive diagnosis of the defective enzyme. The level of ammonia, lactate, acetoacetate beta hydroxybutyrate and pirouette in the blood would indicate whether the phosphoenolpyruvate carboxylase enzyme is defective (Kondo et al., 2019).

Answer 1b

The plasma glucose level is tested twice which includes a 12-hour fasting and a post prandial time which is exactly 2 hours from the time the last meal husband consumed (Kopitar et al., 2020). Is the level of the plasma glucose being higher all lower than that of the normal level during each period of time then it can be assumed that the person is suffering from either hyperglycaemia or hypoglycaemia.

The plasma lactate levels are measured in laboratory by using Roche Diagnostics Cobas 6000 analyser (Tan & Wong, 2021). The normal lactate level is 0.6 to 3.1 mmol/L in  human beings. It is usually measured for determining the presence of lactic acidosis in the patient. The plasma lactate level indicates the presence of either higher or lower amount of lactic acid in the blood which might cause lactic acidosis in the patient.

The plasma pyruvate level a measured in laboratory by pyruvate assay protocol in which pyruvate is oxidised by the pyruvate oxidase for generating colour and fluorescence (Pendleton et al., 2019). As the intensity of the fluorescence is proportional to the content of the pyruvate, the concentration of the pyruvate can be accurately measured through this method.

The plasma ketone level in blood is measured by urine glucose test or by urine analysis. The urine method helps to measure the presence of acetoacetate or acetoacetate and acetone however it does not measure the presence of beta hydroxybutyrate (Sassa et al., 2019).

The selective method used for determining plasma free fatty acid is the gas chromatography following the esterification of target species to the corresponding fatty acid methyl esters. This method utilizes acid catalysed esterification in the methanolic solutions with varying severity for achieving conversion of reactive free fatty acids (Amores & Virto, 2019). The conversion of free fatty acid into fatty acid methyl esters requires rigorous reaction involving a large amount of heat for almost 2 hours.

The metabolic abnormality in this patient the differs from case one is that in this case the patient is fructose intolerance which indicates that an enzyme required for the conversion of fructose to dihydroxyacetone phosphate and glyceraldehyde is defective. As a result of this the fructose is unable to metabolise into other substance causing a rise in the glucose level and dysfunction of the liver ?(Kim et al., 2021).

The enzyme that is defective in the relevant metric pathway in figure 6 is the fructose 1 phosphate aldolase. Therefore, the fructose is not broken down to simpler substances causing a chemical change in the body.

Answer 1c

Fructose is the sweetest sugar among the others and is structurally related to glucose. However, it has lowest glycaemic index than any other sugars (Tappy, 2018). As a result of which, it does not affect the blood glucose level. Although, it is used as energy source for the diabetic patient due to its glycaemic control which do not increase the blood sugar level in diabetic patients and shows minor impact on it. For this property of fructose, health professionals recommend the use of fructose as sweetener start the diabetic patient. Therefore, although glucose and fructose are structurally related to each other, fructose do not interfere with the measurement of glucose in this case. However, since fructose is a ketose sugar, it might give positive result for sugar in blood.

The fructose that appears in urine might be a fraction of it that is derived from the dietary fructose along with hydrolysis of the dietary sucrose which escapes the fructose hepatic metabolism that is passed into systematic circulation (Buziau et al., 2020). The fructose is readily excreted through the urine which is not subjected to district hormonal regulation which is observed in case of glucose. Therefore, fructose can be measured by urine analysis in which the range of the amount of fructose in urine can be measured accurately.

In recent studies it has been observed that paradoxical imbalance in the phosphate metabolism is observed from the initial onset of hypoglycaemia. This imbalance indicates that there is a reduction of the high energy phosphates in the blood (Barros et al., 2019). Several studies have determined that there is a relation between low serum phosphate level and glucose intolerance along with insulin resistance. Fructose intolerance is observed in case of this patient were, withdrawing sugar from the diet resulted from rapid improvement in him. Fructose disappeared from urine sample as well as blood glucose level became normal. Since low serum phosphate level is associated with glucose intolerance and it is evident that glucose and fructose are structurally similar therefore, due to increased level of fructose in blood the plasma phosphate level reduced than the normal range.

From the liver function tests it can be interpreted that the presence of sugar in the diet resulted from presence of fructose in urine which indicated that metabolism pathway is being hampered in him. However, after the withdrawal of sugar fructose disappeared from the urine and blood glucose level returns to normal and the presence of jaundice faded (Chen et al., 2020). The liver restores its normal size which indicated that presence of photos in blood impaired the normal functions of liver and other metabolism due to presence of sugar intolerance in him. Person suffering from fructose intolerance win ingest fructose present in food, it may result from damage of liver and kidney in the patient. Jaundice is a common symptom for liver damage associated with enlargement of the liver and in severe cases chronic liver disease like cirrhosis may also be present.

Answer 2

Several studies have indicated that high amount of fructose intake with food might increase risk of the non-alcoholic fatty liver disease. It is a condition in which higher amount of fat gets stored in the liver cells. This fatty liver disease might lead to the inflammation of the liver causing damage to the liver tissues and sales which results for aggressive diseases like non-alcoholic steatohepatitis (Park et al., 2020). Several studies have determined that consuming higher amount of fructose for patients with fructose intolerance promotes search liver disease which damages the intestinal barrier and cause an inflammation of the liver. Fructose deposits fat on the liver tissues causing fatty liver in the patient.

Lower level of blood sugar is common among patient with among patient who is prescribed to administer insulin or who takes oral diabetes medicines. However, sometimes younger people who do not administer insulin or intake diabetic medications might also suffer from hypoglycaemia (Yale, Paty & Senior, 2018). This is because he might not have been consuming enough food that would help to balance the amount of blood sugar in him. Without sufficient amount of food intake, the action of insulin in the blood might cause a vigorous reduction of the blood sugar level since the amount of substrate for the enzyme has been reduced in the blood. Another reason for such hypoglycaemia can be skipping a meal or postponing the intake of the food for a prolonged time during which the body might exhaust the storage of glycogen in the liver causing a hypoglycaemia condition. Excessive amount of exercise and physical activity and not consuming enough food might also result from hypoglycaemia condition in the student.

From the laboratory result, the diagnosis that is most likely to be observed during the admission are fasting hypoglycaemia, reduced level of sodium, hyponatremia, uraemia, higher level of creatinine, excessive reduced level of cortisol and hypoglycaemia in blood. The level of insulin was also observed in the test result. All the laboratory analysis showed abnormalities in the range of all the metabolites in the diagnosis.

The abnormalities might be due to defective enzymatic activity in the patient. The condition of hypoglycaemia can also result from the abnormalities of the laboratory test of the student (Yale, Paty & Senior, 2018).

In the insulin stress test, it was observed that after 15 minutes of insulin administration symptoms of severe hypoglycaemia. That is why the test was to be aborted and intravenous injection of glucose had to be administered (Xirouchaki et al., 2021). The insulin stress test was positive as the glucose fasting was observed to be much lower than the normal level. The hypoglycaemia condition was because the level of glucose was lower and due to administration of insulin the condition worsen with severe hypoglycaemia.

Answer 3

The plasma glucose level is controlled by 2 main hormones which includes insulin and Glucagon. The insulin and Glucagon hormone are secreted by the pancreas. Glucagon breaks down glycogen to form glucose in the liver. The conversion of glycogen into glucose by Glucagon helps to maintain the blood sugar level in the body during fasting or prolonged absent of food intake by the individual. Glucagon helps to increase the amount of glucose in the blood. On the contrary, insulin is produced when the level of blood glucose is increased and so the action of insulin would help to reduce the excessive amount of glucose in the blood (Ojha et al., 2019).

Enzyme immunoassay is a technique that is used for detecting the presence of enzyme in the serum. The chromogenic substrate specific for the insulin enzyme is added which produces a coloured product (Maggio, 2018). This coloured product helps to accurately measure the amount of insulin in the serum. Intensity of the colour produced in the reaction is proportional to amount of enzyme that are bound to the substrate. Therefore, from intensity of the produced colour amount of enzyme can be calculated from it.

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Answer 4

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