Pediatric Gastroenterology Flashcards

Question

Anal fissure

Answer 1

* most common cause of lower GI bleeding * most cases secondary to constipation * may be the result of sexual abuse * constipation should not create bruising, scarring, anogenital warts or other STDs around the anus

Answer 2

* Broad class of disorders that is the result of an error in a metabolic pathway. * These errors can be from lack of an enzyme, its cofactors, biochemical transporters, and or buildup of a toxic compound. * These disorders are very rare. * IEM screening is included on the newborn screen. * **A negative newborn screen does not rule out disease.****** * When to suspect IEM? * These often present in the newborn period, but depending on the disorder and severity of disease it can present later on in life. * Times of stress can reveal IEM such as fever and fasting. – this is because the kid is stressed and does not have enough energy to compensate for these issues * Symptoms are varied and can include: * Lethargy * Seizures * Hypotonia * Sepsis-like picture * Vomiting * Poor feeding * Hypothermia * Abdominal distention (hepatomegaly) * IEM Categories: * Carbohydrate Metabolism Defects * Protein Metabolism Defects * Amino Acidopathies * Organic Acidopathies * Urea Cycle Defects * Fat Metabolism Defects * Storage Disorders Lysosomal, Peroxisomal, Glycogen * Mitochondria Disorders

Answer 3

* Testing for IEM is complicated and often requires the involvement of medical genetics. * Newborn screen uses tandem mass spectrometry to look for levels of acylcarnitines and amino acids in the blood. * Other testing: * Ammonia * Glucose * Plasma Amino Acids * Urine Organic Acids * Plasma acylcarnitine and carnitine analysis

Answer 4

* Absence of enzyme to breakdown carbohydrate. * Causes buildup of the substrate and this buildup becomes toxic and causes pathology. * Severity of illness depends on what enzyme is affected.

Answer 5

* Deficiency in galactose-1-phosphate uridyltransferase (GALT) * Autosomal Recessive * Presents in neonate following feeding with milk because body is unable to process galactose. * Symptoms: liver failure, renal abnormalities, cataracts, and learning disabilities * Often present with E.coli sepsis. * Treatment based on removal of galactose from the diet.

Answer 6

* Proteins are a string of amino acids that are broken down for energy and excess nitrogen needs to be excreted. * Amino Acidopathies: Result of problem with removing ammonia group from first step of protein metabolism. * Organic Acidopathies: Result of problem with removing intermediates of protein metabolism (deaminated proteins). * Urea Cycle Defects: Problems with cycle that allows for ammonia group to be converted to urea for removal from body. * - often occur when kid is sick and can't process * Amino Acidopathies: Build up of certain amino acids. No metabolic acidosis or hyperammonemia. * Organic Acidopathies: Build up of organic acids results in metabolic acidosis. No hyperammonemia. Presentation: lethargy, vomiting, coma, death. * Urea Cycle Defects: Defect in clearing ammonia. Hyperammonemia, no metabolic acidosis. Presentation: altered metal status, coma, seizure, death * Treatment for all of these include protein restricted diet.

Answer 7

* Deficiency in phenylanine hydroxylase that prevents metabolism of phenylalanine to tyrosine. * Phenylalanine and phenylketones builds up in the tissue and causes brain damage, microcephaly, and eczematous rash. * Treatment includes life long phenylalanine restriction. * Women with PKU are at risk for PKU syndrome. Phenylalanine is a teratogen.

Answer 8

* Fatty acid metabolism is necessary in the body to maintain energy during times of fasting. * Errors in fatty acid metabolism prevent the body from generating energy from fat stores to perform gluconeogenesis. * These disorders are classified by the enzyme that is absent. (Enzymes are classified by the length of the fatty acid chain they work on.) * Medium Chain acyl-CoA dehydrogenase (MCAD)- MOST COMMON * Short Chain acyl-CoA dehydrogenase (SCAD) * Long Chain acyl-CoA dehydrogenase (LCAD) * Very Long Chain acyl-CoA dehydrogenase (VLCAD)

Answer 9

* Symptoms appear in infancy or childhood when children have prolonged periods during fasting or increase metabolic stress (fever). * **Labs are significant for hypoketotic hypoglycemia.** * Acylcarnitine Profile: Demonstrates pattern of acylcarnitines that have built up as a result enzyme deficiency. * Presenting symptoms include: * Sudden death * Seizures * Lethargy

Answer 10

* most common one * MCAD breaks down medium chain fatty acids to short chain and acetyl Co-A. * Autosomal Recessive Disorder * Patients can present as early as day 2 or 3 of life with seizure or sudden death. * If caught prior to presentation (NBS – newborn screen), fasting states can be avoided and patients would be otherwise neurologically normal. * Carnitine supplementation is given as well – one of the reasons for. Carnitine supplementation – because you can’t break down fatty acids, you can’t break them down – carnitine is needed to shuttle them into and out of the cell – if you give more, you can move more fatty acids

Answer 11

* Glycogen- Glycogen is storage form of energy. Disease result of inability of body to metabolize glycogen stores. Patients pre * Lysosome- Organelles that are responsible for digesting large macromolecules. Defects can be in abnormal lysosome formation, enzyme deficiency, or in mechanisms involved in molecular transport. * Peroxisome- Organelles that are involved in multiple cellular functions including: biosynthesis of bile acids, membrane phospholipids, and B-oxidation of long-chain fatty acids. Defects in peroxisomal enzyme function and biogenesis.

Answer 12

* Mitochondria produce energy for the cell through oxidative phosphorylation. Disorders often affect organs with high energy needs: brain, muscle, and eye.