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Pentosuria : Chronic Congenital Pentosuria :A Harmless Metabolic Anomaly

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Pentosuria : Chronic Congenital Pentosuria :A Harmless Metabolic Anomaly University of Nebraska Medical Center DigitalCommons@UNMC MD Theses Special Collections 5-1-1941 Pentosuria : chronic congenital pentosuria :a harmless metabolic anomaly Vance V. Senter University of Nebraska Medical Center This manuscript is historical in nature and may not reflect current medical research and practice. Search PubMed for current research. Follow this and additional works at: https://digitalcommons.unmc.edu/mdtheses Part of the Medical Education Commons Recommended Citation Senter, Vance V., "Pentosuria : chronic congenital pentosuria :a harmless metabolic anomaly" (1941). MD Theses. 884. https://digitalcommons.unmc.edu/mdtheses/884 This Thesis is brought to you for free and open access by the Special Collections at DigitalCommons@UNMC. It has been accepted for inclusion in MD Theses by an authorized administrator of DigitalCommons@UNMC. For more information, please contact [email protected]. PENTCSlntIA: CBRCNIC CCNGENITlU:.1 PENTCSURIA, A HARMLESS METABCLIC ANCMALY. V.MTCE EDW.ARD S"R!>TTER. SEHIOR THESIS PhESENTED TC THE COLLEGE CF MEDI CINE UNIVERSITY CF NEBEASKA, 1941. Table of Contents. 1'.ntroducti on Page 1. Classificatic,n Page 5. Chronic P2nLcsuria, Acquired Type Paf e 8. Toxic Pentosuria Page 15. Aliment,ary Fentosuria Page 18. Cpmplicating Fentosuria Page 19. Chronic Congenital P0ntosuria Page 21. Structure of Urinary Pentose Page 22. Frequency Etiology Possible Relationship to Carbo­ , hydrate Metabolism Page 31. Possible Relationship to Protein Metabolism Page 33. Symptomatc logy Page 38. Diagnosis and Differentic.l. Diagnosis. Page 53. Prognosis Pae·e 64. Treatment Page 65. Conclusions Page 65. Bibliography Page 68. 481257 1. The presence of sugar in the urine is designated by the terms: glycosuria, glucosuria, and melli turia., Cf the three terms the first, glycosuria, is to be preferred because by translation from the Greek, it means "sweet urine" and is broader in its scope than glucosuria which actually only indicates glucose in the urine, or mellituria from the Greek which means "honey urine" as given by Dorland (10). When sugar is found in the urine:, it is quite true t.hat it is nearly always glucose; hence the term glu­ cosuria would be quite correct in most instances. Meire uncommonly, however, certain other sugars may be present e.s certain disacchar~es, lactose, galactose, fructose, and pentose (10). The finding of sugar in the uri:ae may be entirely physiological as for example its appearance fo llcwing excessive carbohydrate ingestion. This is appropriate­ ly termed alimentary glycosuria. It is simply the re· sult of the inability of t~e liver to synthesize to 2. to glycogen all of the sudden load of sugar trought to it from the int,estine. Hence there is some spi L.l over when the renal threshold is reached, and sugar appears in the urine. The sugar may be one of the hexoses as glucose or galactose or more uncommonly the disaccharides as sucrose or maltose. The diis­ accharides are found in the urine when large amounts have been ingested, and merely represent the in­ ability of t~1e liver to cope with the disaccharide molecule which has been picked up by the intestine(lO). Latctosuria is an occasional observation d!uring the latter part of' pregnancy and during the lactating period. It is more :frequent during the weaning period. Galactose is :found in the urine of' infants, v:hich fact is probably to be explained on the basis of' in­ complete conversion of' galactose into glycogen by liver action (10). Pathologically, lactosuria is seen in certain cases of gastric carcinoma possibly be­ cause of the lactose generated within the stomach which sugar is picked up directly :from the stomach wall (63) We must also mention pancreatic diabetes and renal glycosuria which will be cons1dered further in rela­ tion to the topic of discussion. Pancreatic diabetes is the most important and cowmen cause of glycosuria when considered clinically. 3. Hyperglycemia occurs here as the result of the slowed or incomplete tra11sformation of the mono­ hexose sugar to glycogen because cf either a rel­ ative or an absolute decrease of pancreatic hor­ mone. When the renal threnold for glucose is ex­ ceeded, the sugar flows over into the urine (10). Renal glycosuria is a type of glycosuria in which there is increased kidney penmeability to sugar. It is distinguished by the low blood sugar values in contrast to the heightened values of pancreat­ ic diabetes (10). Cther features will be noted JLater on. The reader should be convinced by this time,that glucose is only one cf many sugars found in the urine. And of these urinary sugara, the author has chosen pentosuria for dissertation. It is true that "pentosuria consti tu"t.es as yet little more th on a clinical curiosi ty"in the words of Solis­ Cohen (71),but it has suggested many questions, which answers when found,will doubtless be illum­ inating as to certain dark corners of the field of metabolism. The sugar in this condition is penta­ tomic in contrast to the other urinary sugars which are either mono or dihexoses. The condition is interesting because it seems to 4. be an he1·edi tary linl<ed ccndi ti on. It hc~s been con- sid.ered as part of many ccndi ticns to te later re­ lated. hece:c1tly it has led to tr~e sti;1mlation of research in the study cf pentose metabolism. Even though the coridi tion would be usually considered as unimportant it should be a stimulant as a curiosity to the medical scientist. Garrod (27) reviews the early literature of pen­ tosuria. Briefly, pentosuria was discovered onl~r a few years after the discovery of the existence of sugars of 1,,he pentose 2rcup. It was shcvm that aral,inose, the sugar obtained f'rcm gu..-:1 arctlic which had been previcusly claes1f1ed as a hexc se contained c,nly 5 carbon atoms. TY.is occurred as late as lbS7. Shortly a.fter\vard j~;:rlose, tl1e sugar obtained frcm w( cd, was 1_1roved to a pentose. In addition, many vegetable structures were found to contain pentcs­ ans, that is, polysaccharides which on hydrolysis yiel6. the pentoses. The first c2,se cf chronic pentosuria was reported bJ Salkowski and Jastrovn tz {@7) in 12.92. Salkowski considered the condition not as a disease entity, but rather as a harmless rr~etabclic ar.orr..aly which the author will substantiate in this thesis. This case happened to be a mcr:;::;hine aa.r.::ict, and thcugl. the opiate vvo.s stepped, pentose remc:.ined in the urine; hence the condition was knn;n as chronic essential pentosuria. Analyzing the urine cf tt...is addict these vvorke:es (67) only, coincidentally fcund t~at the urine con­ tained a sugar, the osazone of which had a melting point between 157 and 158 c. and was soluble in hot water. This was in contrast to the osazone obtc..in­ ed from glucose which had a higher melting point and was relatively insoluble in water. The low melt­ ing point of the osazone suegested tc these investi­ gators that the sugar present in their patient's urine was a pentose. Classification \'.i th Definition of Types. Classification is appro1'iate at this point to clarify our further discussion. Pentosuria has been classified in several ways, but as time has passed, the classification has been somewhat.as the follow­ ing, which is modified from Margolis (52). l. Chronic pentosuria:(a) Congenital;{b) ac'1_Uired 2. Temporary toxic pentosuria. 3. Alimentary pentosuria. 4. Complicating pentosuria. As regards chronic or essential pentosuria, this condition bears nc relation whatsoever to the diet of 6. the individual. There is no definite cause so far determined. Renal function is not impaired accord­ int to the knovm me'Ul ods of testing. Blood sugar levels are normal and remain within normal limits in spite cf the ingestion of large amounts of glu­ cose. There are no symptoms of true diabetes. Pen­ tose is present in the urine continuously fer an in­ definite number of years (39). Congenital chronic pentosuria refers to the type in which there is an inherited factor present. According to Garrod,(27) inborn errors of metabolism are nv.ont to occur in several members of a family, most often in brothers and sisters whose pa.rents do not share their pecul­ 1 iarity, and whose children are also iJ11mune. ' He cites statistics which demonstrate the occur-rence of the corr<moner anemalies of metabolism as being of higher incidence among males. It seems there is a de:fini te law governing its transmis,1ion • But according to Margolis (52) there are some cases which seem to nave been acquired. These are called acquired pent-0surias. Theoretically the congenital type should be present from birth, and other cases should be fcund in the family. In the acquired cases there occurs the presence of' continuous pent­ ()Suria in the urine of an individual who has pre- 7. viously not had reducing substances in his urine. such a condition is apparently brought on or aggra- vated by infections, nervous traumata, or ether traumata to the body. Most reviewers of literature have failed to men- tion toxic pentosuria, but it certainly has its place because the condition has been reported many times and is substantiated by experiment as will be / seen in the following. The condition is termed tem- porary and toxic because it occurs with the use of opiates, and certain of the barbiturates, and pyr­ amidon, and disappears when the particular drug is discontinued. As regards ancther division of the subject, ali­ mentary pentosuria,Rossen (65) defines it as a transi- tory phenomenon in which the pentoseA1n<W-/>f!<l.rs the urine of perfectly normal people after the ingestion of fresh fruits such as plums, pears, cherries, strawberrie~, and apples.
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