Descriptions of conditions
Chylothorax
Chylothorax refers to the presence of lymphatic fluid in the pleural space secondary to leakage from the thoracic duct or one of its main tributaries. A tear or leak in the thoracic duct causes chylous fluid to collect in the pleural cavity, which can cause acute or chronic alterations in the pulmonary mechanics.
Symptoms are e.g. decreased breath sounds and milky white fluid in the chest.
Treatment options are surgery or dietary therapy. The aim of dietary therapy is to reduce the production of chyle by instituting TPN or a fat-restricted oral diet with medium-chain triglycerides.
Bibliography
Cormack, BE et al. (2004) Use of Monogen for pediatric postoperative chylothorax. Ann Thorac Surg.; 77(1):301-5
Cows’ Milk Allergy (CMA)
Cows’ Milk Allergy (CMA), also known as Cows’ Milk Protein Allergy (CMPA) is an adverse reaction to the protein in cow’s milk that involves the immune system. This condition can affect various body systems and symptoms can include vomiting, diarrhea, eczema, atopic dermatitis and asthma as well as failure-to-thrive. Nutritional therapy with an amino acid-based formula has been shown to be most effective in very sensitive children.
Bibliography:
de Boissieu D et al. Allergy to extensively hydrolyzed cow milk proteins in infants: identification and treatment with an amino acid-based formula. J Pediatr. 1997; 131:744-747
Eosinophilic esophagitis (EE)
Eosinophilic esophagitis (EE) is an inflammatory condition of the esophagus. Its principal cause is food allergy. Eosinophils, a type of white blood cells typically not present in the esophagus, are considered markers of inflammation and are elevated in EE. Symptoms of EE include:
- Reflux that does not respond to usual therapy (which includes proton pump inhibitors: a medicine which stops acid production in the stomach)
- Dysphagia
- Food impactions
- Nausea and Vomiting
- Failure to thrive Abdominal or chest pain
- Poor appetite
- Malnutrition
Diagnosis can only be confirmed through biopsy. The most effective treatment in EE is nutritional therapy with an amino acid-based formula.
Bibliography:
Markowitz, et al. Elemental diet is an effective treatment for eosinophilic esophagitis in children and adolescents. Am J Gastroenterol. 2003 Apr. 98(4):777-82.
Kelly KJ et al. Eosinophilc esophaghigitis attributed to gastroesophageal reflux: improved with an amino acid-based formula. Gastroenterology. 1995;109;1503-1512
Epilepsy
Epilepsy is the most common neurological disorders and can be defined as the condition of unprovoked, recurring seizures. It is thought that up to 5% of the world’s population may have some form of seizure in their life time. Only those with recurring seizures will be diagnosed with epilepsy. It can occur in male or female, adult or child.
The World Health Organization (WHO) estimates the prevalence to be approximately 8.2 per 1000 of the population. This equates to 50 million people across the world. It also means that there are approximately 100 million people who have either suffered from epilepsy, are suffering from epilepsy or will suffer from epilepsy.
Individuals with epilepsy may experience subtle interruptions of awareness and responsiveness to a major convulsion attack of the whole body. It cannot be considered as a single medical condition. There are many reasons why an individual would have these attacks, also known as seizures or fits.
Studies have shown that 70% of individuals diagnosed with Epilepsy can be treated successfully with anti epileptic drugs.
Many studies and sources, however, fail to mention the Ketogenic Therapy (or Ketogenic Diet as it is also known). The ketogenic diet should be tried more frequently then it is at the moment. If anti-epileptic drugs have had no impact on 2 occasions, then the Ketogenic Diet should be tried.
Bibliography
Kossoff EH, et al .Optimal clinical management of children receiving the ketogenic diet: Recommendations of the International Ketogenic Diet Study Group. Epilepsia. 2008 Sep 23.
Neal EG et al. The ketogenic diet for the treatment of childhood epilepsy: a randomized, controlled trial. Lancet Neurol 2008; 7: 500-506
Fatty Acid Oxidation Disorders (FAO)
Fatty Acid Oxidation Disorders (FAO) are a group of inherited metabolic conditions that lead to an accumulation of fatty acids and a decrease in cell energy metabolism. Each fatty acid oxidation disorder is associated with a specific enzyme defect in the fatty acid metabolic pathway. The utilization of dietary and stored fat is affected. FAO are classified into very short chain, medium chain, long chain and very long chain fatty acid oxidation disorders.
Treatment varies depending on the disorder. In general, nutrition therapy attempts to avoid fasting and limit the intake of the fatty acids that cannot be metabolized.
Bibliography
Stanley CA. Disorders of Fatty Acid Oxidation. In: Inborn Metabolic Diseases (Fernandes J et al editors); Berlin: Springer, 2000; 141-150
Gastroesophageal Reflux Disease (GERD)
Gastroesophageal Reflux Disease (GERD) is primarily a motility disorder whereas the lower esophageal sphincter is malfunctioning. This allows for the reflux of stomach content into the esophagus. Food allergy is the most common cause of secondary GERD. Symptoms are esophagitis, reflux, vomiting and failure to thrive.
An Amino acid-based formula is the preferred line of treatment.
Bibliography
Vandenplas. Symptoms, diagnosis, and management of colicky infants with regurgitation. ISPGHN 2002; 11: 1-8
De Boissieu et al. Allergy to extensively hydrolyzed cow’s milk protein in infants: identification and treatment with an amino acid-based formula. J Pediatr 1997;131:744-7.
Glutaric Aciduria Type I
Glutaric Aciduria Type I is a rare inherited disorder caused by a deficiency of glutaryl-CoA dehydrogenase, resulting in progressive neurological deterioration. The aim of dietary management is to limit lysine and tryptophan by means of a low protein diet. The protein requirements are met by supplementing the diet with a lysine-free and low tryptophan amino acid mixture if necessary.
Carnitine is routinely used, and riboflavin as a vitamin cofactor. Baclofen has also been recommended.
Emergency regimes are critical in periods of decompensation and catabolism.
Bibliography
Baric I, Zschoke J, Christensen B, Duran M, Goodman SI, Leonard JV, Muller E,
Morton DIJ, Superti-Purga A, Hoffman GF. Diagnosis and management of glutaric aciduria type I. J Inher Metab Dis. 1998;21:326-340
Monavari AA, Naughten ER. Prevention of cerebral palsy in Glutaric Aciduria type I by dietary management. Arch Dis Child 200;82:67-70
Homocystinuria
Classical Homocystinuria is an inherited disorder caused by Cystathione β-synthetase deficiency resulting in mental retardation, eye problems, and risk of thrombosis. The aim of dietary management is to prevent the accumulation of methionine by means of a low methionine diet. Protein requirements are met by supplementing the diet with a methionine-free amino acid mixture, which contains cystine.
Cystine levels should be monitored and may need supplementing depending upon the patient’s individual tolerance.
Betaine is often used to assist in re-methylation. Milder variants of Homocystinuria may be partially or totally vitamin B6 responsive. Folic acid supplementation may also be required.
Bibliography
Yap S, Naughten E. Homocystinuria due to cystathionine beta-synthase deficiency in Ireland: 25 years experience of a newborn screened and treated population with reference to clinical outcome and biochemical control. J Inher Metab Dis. 1998;21738-747.
Isovaleric Acidemia and Disorders of Leucin Metabolism
Isovaleric Acidemia (IVA) is a rare inherited disorder affecting leucine metabolism caused by a deficiency of isovaleryl-CoA dehydrogenase.
The disease can present itself in a variety of forms from a severe presentation to a much milder form. Symptoms will vary from individual to individual and include drowsiness, rapid breathing and vomiting. A spell in hospital is often necessary to stabilize the infant/child and the hospital team will provide information and guidance on how to manage the child’s condition.
The aim of dietary management is to limit dietary leucine intake and minimize formation of isovaleric acid by means of a low protein diet. The protein requirements are met by supplementing the diet with a leucine-free amino acid mixture if necessary.
Bibliography
de Baulny HO et al. Branched-chain organic acidurias. In: Inborn Metabolic Diseases (Fernandes J et al editors); Berlin: Springer, 2000; 196-212
Maple Syrup Urine Disease (MSUD)
Maple Syrup Urine Disease (MSUD) is a rare inherited disorder affecting the metabolism of leucine, isoleucine and valine.
The disease can present itself in a variety of forms from a severe presentation to a much milder form. Symptoms will vary from individual to individual and include drowsiness, rapid breathing and vomiting. A spell in hospital is often necessary to stabilize the infant/child and the hospital team will provide information and guidance on how to manage a child’s condition.
The aim of dietary management is to prevent the accumulation of the branched chain amino acids by means of a low protein diet. The protein requirements are met by supplementing the diet with a leucine-, isoleucine- and valine-free amino acid mixture, and by a small amount of natural protein to provide the necessary leucine, isoleucine and valine requirements. The natural protein intake is based on leucine requirements, and additional isoleucine and valine may be required as supplement.
Whilst dietary management is a key part of MSUD treatment there are milder variants of the disorder which are also vitamin responsive (thiamin).
Emergency regimes are required in periods of decompensation and catabolism.
Bibliography
Report of Medical Research Council on the Dietary Management of Phenylketonuria. Recommendations on the Dietary Management of Phenylketonuria. Arch. Dis. Child. 1993;68: 426-7
Lawson M, Shaw V (eds.). Clinical Paediatric Dietetics 2nd ed. Oxford:Blackwell Science, 2001.
DH Morton. “Diagnosis and Treatment of MSUD: A Study of 36 Patient” Pediatrics 2002; 109: 999-1008
Methylmalonic Acidemia and Propionic Acidemia
Methylmalonic Acidemia (MMA) and Propionic Acidemia (PPA) are disorders of propionate metabolism.
The disease can present itself in a variety of forms from a severe presentation to a much milder form. Symptoms will vary from individual to individual and include drowsiness, rapid breathing and vomiting. A spell in hospital is often necessary to stabilize the infant/child and the hospital team will provide information and guidance on how to manage a child’s condition.
The aim of dietary management is to limit production of propionate by restricting methionine, threonine, valine and isoleucine by means of a low protein diet. Protein requirements are met by supplementing the diet with a methionine-, threonine-, valine- and isoleucine-free amino acid mixture.
Carnitine is used as it may be effective in encouraging urinary propionyl-carnitine excretion and preventing carnitine depletion. Metranidazole is often prescribed to limit propionate production by gut bacteria.
Emergency regimes are required in periods of decompensation and catabolism.
Bibliography
de Baulny HO et al. Branched-chain organic acidurias. In: Inborn Metabolic Diseases (Fernandes J et al editors); Berlin: Springer, 2000; 196-212
Phenylketonuria (PKU)
Phenylketonuria (PKU) is an inherited disorder of phenylalanine metabolism, caused by a deficiency of the enzyme phenylalanine hydroxylase, which leads to mental retardation if untreated. The aim of dietary management is to prevent the accumulation of phenylalanine by means of a low phenylalanine diet. Protein requirements are met by supplementing the diet with a phenylalanine-free amino acid mixture. Phenylalanine requirements are met by including a small amount of natural protein in the diet. In certain circumstances (such as pregnancy) an additional tyrosine supplement may be required.
Bibliography
Dixon M., MacDonald A, White F. Disorders of Amino Acid Metabolism, Organic
Acidemias and Urea Cycle Defects, Phenylketonuria in Lawson M, Shaw V (eds.).
Clinical Paediatric Dietetics. Oxford: Blackwell Science, 2001, p233 - 294
NIH Consensus Statement. Phenylketonuria (PKU): Screening and Management. Volume 17, Number 3, October 2000. National Institutes of Health.
Report of Medical Research Council on the Dietary Management of Phenylketonuria. Recommendations on the Dietary Management of Phenylketonuria. Arch. Dis. Child. 1993: 68; 426-7.
Sulphite Oxidase Deficiency
Sulphite Oxidase deficiency is a rare inherited disorder affecting sulphite metabolism resulting in severe neurological dysfunction, mental retardation and lens dislocation. A clinically mild form is treatable with diet. Protein requirements are met by supplementing the diet with a cystine- and methionine-free amino acid mixture, in conjunction with a low methionine and cystine diet.
Bibliography
Touati G, Rusthoven E, Depondt E, et al. Dietary Therapy in two patients with a mild form of Sulphite Oxidase Deficiency. Evidence for clinical and biological improvement. J. Inher. Metab. Dis. 2000;23:45-53.
Tyrosinemia
There are several types of Tyrosinemia caused by disorders of tyrosine metabolism, which are relatively rare.
Tyrosinemia Type l
Tyrosinemia type I is caused by a deficiency of fumarylacetoacetate hydroxylase resulting in severe liver and kidney failure and eventually death. The aim of dietary management is to prevent the accumulation of phenylalanine, tyrosine and sometimes methionine by means of a low protein diet. The protein requirements are met by supplementing the diet with a tyrosine-, phenylalanine- and/or methionine-free amino acid mixture. If NTBC is prescribed then a phenylalanine- and tyrosine-free protein substitute is normally used. A phenylalanine-, tyrosine- and methionine-free protein substitute is used only when the patient is unresponsive to NTBC or it is unavailable. Whilst dietary management is important in Tyrosinemia, NTBC has significantly improved management and survival in Tyrosinemia type I.
Tyrosinemia Type II
Tyrosinemia type II is caused by a deficiency of tyrosine aminotransferase leading to eye lesions, skin lesions and neurological complications. The aim of dietary management is to prevent the accumulation of phenylalanine and tyrosine by means of a low protein diet. The protein requirements are met by supplementing the diet with a tyrosine- and phenylalanine-free amino acid mixture.
Tyrosinemia Type lll
Tyrosinemia type III is a very rare form of Tyrosinemia resulting in convulsions, ataxia and mental retardation. The aim of dietary management is to prevent the accumulation of phenylalanine and tyrosine by means of a low protein diet. The protein requirements are met by supplementing the diet with a tyrosine- and phenylalanine-free amino acid mixture.
Bibliography
Dixon M., MacDonald A, White F. Disorders of Amino Acid Metabolism, Organic Acidemias and Urea Cycle Defects, Phenylketonuria in Lawson M, Shaw V (eds.). Clinical Paediatric Dietetics. Oxford:Blackwell Science, 2001,p233-294.
Holme E, Linstedt S. Tyrosinemia type I and NTBC (2-(2-nitro-4-triflourom othylbenoyl)-1,3-cyclohexanedione). J. Inherit. Metab. Dis. 1998:21;507-517.
Ellaway CJ., Holme E, Standing S. et al. Outcome of Tyrosinemia type III. J. Inherit. Metab. Dis 2001:24;824-32.
Urea Cycle Disorders
Urea Cycle Disorders (UCD) are a group of inherited conditions, characterized by enzyme deficiencies of the urea cycle. The result is waste nitrogen accumulating as ammonia and glutamine, both of which are neurotoxic and may cause severe encephalopathy. The aim of dietary management is to restrict dietary protein by means of a low protein diet. The protein requirements are met by supplementing the diet with an essential amino acid mixture if necessary, and/or specific individual amino acids such as arginine and citrulline depending upon the type of Urea Cycle Defect. A high calorie diet is also an important aspect of dietary management
Sodium benzoate and phenylbutyrate are used in conjunction with diet therapy to facilitate the removal of nitrogen.
Emergency regimes are required in periods of decompensation and catabolism.
Bibliography
Leonard JV. Disorders of Urea Cycle. In: Inborn Metabolic Diseases (Fernandes J et al editors); Berlin: Springer, 2000; 213-222
|
