202:
36:
474:
273:
represents the mass of nitrogen within urea/volume, not the mass of whole urea. Each molecule of urea has two nitrogen atoms, each having molar mass 14 g/mol. To convert from mg/dL of blood urea nitrogen to mmol/L of urea:
624:
224:
BUN is usually reported in mg/dL in some countries (e.g. United States, Mexico, Italy, Austria, and
Germany). Elsewhere, the concentration of urea is reported in SI units as mmol/L.
271:
846:
279:
195:
216:, which is a genetic disorder inherited in an X-linked recessive pattern. OTC deficiency is also accompanied by hyperammonemia and high orotic acid levels.
839:
486:
712:
832:
755:
478:
Note that molar concentrations of urea and urea nitrogen are equal, because both nitrogen gas and urea has two nitrogen atoms.
809:
739:
688:
213:
1206:
1144:
679:
Lewis, Sharon Mantik; Dirksen, Shannon Ruff; Heitkemper, Margaret M.; Bucher, Linda; Harding, Mariann (5 December 2013).
800:
Loscalzo, Joseph; Fauci, Anthony S.; Kasper, Dennis L.; Hauser, Stephen; Longo, Dan; Jameson, J. Larry (2022-04-05).
773:
194:
The main causes of a decrease in BUN are malnutrition (low-protein diet), severe liver disease, anabolic state, and
205:
122:
1408:
121:
should contain 7 to 18 mg/dL (0.388 to 1 mmol/L) of urea nitrogen. Individual laboratories may have different
1345:
1101:
1403:
1037:
999:
83:
79:
75:
71:
1378:
180:, rapid cell destruction from infections, athletic activity, excessive muscle breakdown, and increased
161:
67:
201:
929:
1079:
469:{\displaystyle Urea_{mmol/L}=BUN_{mmol/L}=BUN_{mg/dL}*{\frac {10_{dL/L}}{14*2}}=BUN_{mg/dL}*0.3571}
173:
48:
1413:
1074:
942:
907:
188:
138:
229:
1340:
1194:
1089:
1032:
994:
1134:
1111:
1096:
1027:
1332:
1189:
1177:
1154:
1084:
1009:
877:
647:
20:
8:
1170:
1165:
1062:
652:
966:
887:
706:
1272:
1251:
919:
914:
805:
759:
735:
728:
694:
684:
642:
824:
802:
Harrison's
Principles of Internal Medicine, Twenty-First Edition (Vol.1 & Vol.2)
1362:
1019:
1216:
1355:
1350:
54:
1221:
1263:
1119:
892:
882:
165:
681:
Medical-surgical nursing : assessment and management of clinical problems
191:
has been found to be lowered in hypothyroidism and raised in hyperthyroidism.
149:
BUN is an indication of kidney health. The normal range is 2.1–7.1 mmol/
1397:
1306:
1285:
1199:
1124:
1057:
698:
619:{\displaystyle Urea_{mg/dL}=BUN_{mg/dL}*{\frac {60}{14*2}}=BUN_{mg/dL}*2.14}
1311:
1280:
1183:
872:
160:
The main causes of an increase in BUN are: high-protein diet, decrease in
1129:
1069:
1004:
957:
952:
947:
864:
169:
1049:
989:
976:
897:
856:
181:
134:
106:
1211:
1139:
937:
154:
110:
1301:
1233:
984:
102:
1241:
187:
Hypothyroidism can cause both decreased GFR and hypovolemia, but
114:
35:
1246:
130:
208:, comparing urea (yellow at right) to other blood constituents
725:
628:
Where 60 represents MW of urea and 14*2 MW of urea nitrogen.
177:
150:
126:
118:
62:
678:
637:
99:
40:
799:
481:
Convert BUN to urea in mg/dL by using following formula:
758:. Marshal University School of Medicine. Archived from
854:
489:
282:
232:
804:. New York: McGraw Hill Professional. p. 611.
727:
618:
468:
265:
1395:
98:) is a medical test that measures the amount of
105:found in blood. The liver produces urea in the
774:"Blood urea nitrogen (BUN) test - Mayo Clinic"
196:syndrome of inappropriate antidiuretic hormone
133:problems. It is not considered as reliable as
840:
734:. New York: McGraw-Hill Medical. Last page.
847:
833:
726:Tao Le; Vikas Bhushan; Deepak Rao (2007).
711:: CS1 maint: location missing publisher (
34:
19:"BUN" redirects here. For other uses, see
212:Another rare cause of a decreased BUN is
200:
748:
719:
1396:
828:
683:(9th ed.). St. Louis, Missouri.
214:ornithine transcarbamylase deficiency
795:
793:
674:
672:
670:
668:
1145:Glycogen phosphorylase isoenzyme BB
730:First Aid for the USMLE Step 1 2008
13:
14:
1425:
790:
665:
144:
206:Reference ranges for blood tests
176:, gastrointestinal hemorrhage,
766:
1:
1102:Comprehensive metabolic panel
658:
168:), decrease in blood volume (
129:. The test is used to detect
125:, as they may use different
7:
1038:Thyroid-stimulating hormone
1000:Total iron-binding capacity
631:
266:{\displaystyle BUN_{mg/dL}}
10:
1430:
1379:Elevated alpha-fetoprotein
162:glomerular filtration rate
109:as a waste product of the
18:
1371:
1331:
1324:
1294:
1271:
1262:
1232:
1153:
1110:
1048:
1018:
975:
928:
863:
61:
47:
33:
28:
219:
174:congestive heart failure
908:BUN-to-creatinine ratio
189:BUN-to-creatinine ratio
139:BUN-to-creatinine ratio
1341:Elevated transaminases
1033:Thyroid function tests
995:Transferrin saturation
855:Clinical biochemistry
620:
470:
267:
209:
117:. Normal human adult
1409:Diagnostic nephrology
1135:Lactate dehydrogenase
1097:Basic metabolic panel
1028:ACTH stimulation test
762:on December 16, 2014.
621:
471:
268:
204:
164:(GFR) (suggestive of
1155:Liver function tests
1010:Transferrin receptor
756:"Normal Lab Results"
648:Urea reduction ratio
487:
280:
230:
21:Bun (disambiguation)
1171:Serum total protein
1166:Human serum albumin
653:Urine urea nitrogen
92:Blood urea nitrogen
29:Blood urea nitrogen
1404:Chemical pathology
943:Arterial blood gas
778:www.mayoclinic.org
616:
466:
263:
210:
1391:
1390:
1387:
1386:
1320:
1319:
1273:Blood sugar level
1252:Pancreatic lipase
1090:Total cholesterol
920:Serum osmolal gap
915:Plasma osmolality
811:978-1-264-26851-1
741:978-0-07-149868-5
690:978-0-323-10089-2
643:Standardized Kt/V
575:
425:
89:
88:
1421:
1363:Hyperproteinemia
1329:
1328:
1269:
1268:
849:
842:
835:
826:
825:
816:
815:
797:
788:
787:
785:
784:
770:
764:
763:
752:
746:
745:
733:
723:
717:
716:
710:
702:
676:
625:
623:
622:
617:
609:
608:
601:
576:
574:
560:
555:
554:
547:
522:
521:
514:
475:
473:
472:
467:
459:
458:
451:
426:
424:
413:
412:
408:
392:
387:
386:
379:
354:
353:
349:
318:
317:
313:
272:
270:
269:
264:
262:
261:
254:
153:or 6–20 mg/
123:reference ranges
57:
38:
26:
25:
1429:
1428:
1424:
1423:
1422:
1420:
1419:
1418:
1394:
1393:
1392:
1383:
1367:
1356:Hypoalbuminemia
1351:Hypoproteinemia
1316:
1290:
1264:Small molecules
1258:
1228:
1149:
1106:
1044:
1014:
971:
961:
924:
859:
853:
822:
820:
819:
812:
798:
791:
782:
780:
772:
771:
767:
754:
753:
749:
742:
724:
720:
704:
703:
691:
677:
666:
661:
634:
597:
590:
586:
564:
559:
543:
536:
532:
510:
503:
499:
488:
485:
484:
447:
440:
436:
414:
404:
397:
393:
391:
375:
368:
364:
345:
332:
328:
309:
296:
292:
281:
278:
277:
250:
243:
239:
231:
228:
227:
222:
147:
141:blood studies.
53:
43:
24:
17:
12:
11:
5:
1427:
1417:
1416:
1414:Nitrogen cycle
1411:
1406:
1389:
1388:
1385:
1384:
1382:
1381:
1375:
1373:
1369:
1368:
1366:
1365:
1360:
1359:
1358:
1348:
1343:
1337:
1335:
1326:
1322:
1321:
1318:
1317:
1315:
1314:
1309:
1304:
1298:
1296:
1292:
1291:
1289:
1288:
1283:
1277:
1275:
1266:
1260:
1259:
1257:
1256:
1255:
1254:
1244:
1238:
1236:
1230:
1229:
1227:
1226:
1225:
1224:
1219:
1209:
1204:
1203:
1202:
1197:
1192:
1180:
1175:
1174:
1173:
1168:
1159:
1157:
1151:
1150:
1148:
1147:
1142:
1137:
1132:
1127:
1122:
1120:Cardiac marker
1116:
1114:
1112:Cardiovascular
1108:
1107:
1105:
1104:
1099:
1094:
1093:
1092:
1087:
1082:
1077:
1067:
1066:
1065:
1063:Hemoglobin A1c
1054:
1052:
1046:
1045:
1043:
1042:
1041:
1040:
1030:
1024:
1022:
1016:
1015:
1013:
1012:
1007:
1002:
997:
992:
987:
981:
979:
973:
972:
970:
969:
964:
959:
955:
950:
945:
940:
934:
932:
926:
925:
923:
922:
917:
912:
911:
910:
905:
900:
893:Renal function
890:
885:
880:
875:
869:
867:
861:
860:
852:
851:
844:
837:
829:
818:
817:
810:
789:
765:
747:
740:
718:
689:
663:
662:
660:
657:
656:
655:
650:
645:
640:
633:
630:
615:
612:
607:
604:
600:
596:
593:
589:
585:
582:
579:
573:
570:
567:
563:
558:
553:
550:
546:
542:
539:
535:
531:
528:
525:
520:
517:
513:
509:
506:
502:
498:
495:
492:
465:
462:
457:
454:
450:
446:
443:
439:
435:
432:
429:
423:
420:
417:
411:
407:
403:
400:
396:
390:
385:
382:
378:
374:
371:
367:
363:
360:
357:
352:
348:
344:
341:
338:
335:
331:
327:
324:
321:
316:
312:
308:
305:
302:
299:
295:
291:
288:
285:
260:
257:
253:
249:
246:
242:
238:
235:
221:
218:
166:kidney failure
146:
145:Interpretation
143:
87:
86:
65:
59:
58:
51:
45:
44:
39:
31:
30:
15:
9:
6:
4:
3:
2:
1426:
1415:
1412:
1410:
1407:
1405:
1402:
1401:
1399:
1380:
1377:
1376:
1374:
1370:
1364:
1361:
1357:
1354:
1353:
1352:
1349:
1347:
1344:
1342:
1339:
1338:
1336:
1334:
1330:
1327:
1323:
1313:
1310:
1308:
1307:Hyperuricemia
1305:
1303:
1300:
1299:
1297:
1293:
1287:
1286:Hyperglycemia
1284:
1282:
1279:
1278:
1276:
1274:
1270:
1267:
1265:
1261:
1253:
1250:
1249:
1248:
1245:
1243:
1240:
1239:
1237:
1235:
1231:
1223:
1220:
1218:
1215:
1214:
1213:
1210:
1208:
1205:
1201:
1200:AST/ALT ratio
1198:
1196:
1193:
1191:
1188:
1187:
1186:
1185:
1184:transaminases
1181:
1179:
1176:
1172:
1169:
1167:
1164:
1163:
1161:
1160:
1158:
1156:
1152:
1146:
1143:
1141:
1138:
1136:
1133:
1131:
1128:
1126:
1125:Troponin test
1123:
1121:
1118:
1117:
1115:
1113:
1109:
1103:
1100:
1098:
1095:
1091:
1088:
1086:
1085:Triglycerides
1083:
1081:
1078:
1076:
1073:
1072:
1071:
1068:
1064:
1061:
1060:
1059:
1058:Blood glucose
1056:
1055:
1053:
1051:
1047:
1039:
1036:
1035:
1034:
1031:
1029:
1026:
1025:
1023:
1021:
1017:
1011:
1008:
1006:
1003:
1001:
998:
996:
993:
991:
988:
986:
983:
982:
980:
978:
974:
968:
965:
963:
956:
954:
951:
949:
946:
944:
941:
939:
936:
935:
933:
931:
927:
921:
918:
916:
913:
909:
906:
904:
901:
899:
896:
895:
894:
891:
889:
886:
884:
881:
879:
876:
874:
871:
870:
868:
866:
862:
858:
850:
845:
843:
838:
836:
831:
830:
827:
823:
813:
807:
803:
796:
794:
779:
775:
769:
761:
757:
751:
743:
737:
732:
731:
722:
714:
708:
700:
696:
692:
686:
682:
675:
673:
671:
669:
664:
654:
651:
649:
646:
644:
641:
639:
636:
635:
629:
626:
613:
610:
605:
602:
598:
594:
591:
587:
583:
580:
577:
571:
568:
565:
561:
556:
551:
548:
544:
540:
537:
533:
529:
526:
523:
518:
515:
511:
507:
504:
500:
496:
493:
490:
482:
479:
476:
463:
460:
455:
452:
448:
444:
441:
437:
433:
430:
427:
421:
418:
415:
409:
405:
401:
398:
394:
388:
383:
380:
376:
372:
369:
365:
361:
358:
355:
350:
346:
342:
339:
336:
333:
329:
325:
322:
319:
314:
310:
306:
303:
300:
297:
293:
289:
286:
283:
275:
258:
255:
251:
247:
244:
240:
236:
233:
225:
217:
215:
207:
203:
199:
197:
192:
190:
185:
183:
179:
175:
171:
167:
163:
158:
156:
152:
142:
140:
136:
132:
128:
124:
120:
116:
112:
108:
104:
101:
97:
93:
85:
81:
77:
73:
69:
66:
64:
60:
56:
52:
50:
46:
42:
37:
32:
27:
22:
1346:Elevated ALP
1312:Hypouricemia
1281:Hypoglycemia
1217:Unconjugated
1182:
902:
865:Electrolytes
821:
801:
781:. Retrieved
777:
768:
760:the original
750:
729:
721:
680:
627:
483:
480:
477:
276:
226:
223:
211:
193:
186:
159:
148:
95:
91:
90:
1295:Nitrogenous
1130:CPK-MB test
1070:Lipid panel
1005:Transferrin
953:Bicarbonate
948:Base excess
857:blood tests
170:hypovolemia
1398:Categories
1222:Conjugated
1050:Metabolism
990:Serum iron
977:Iron tests
898:Creatinine
783:2019-05-13
659:References
182:catabolism
135:creatinine
107:urea cycle
16:Blood test
1212:Bilirubin
1162:Proteins
1140:Myoglobin
938:Anion gap
930:Acid-base
878:Potassium
707:cite book
699:228373703
611:∗
569:∗
557:∗
461:∗
419:∗
389:∗
111:digestion
1325:Proteins
1302:Azotemia
1234:Pancreas
1020:Hormones
985:Ferritin
883:Chloride
632:See also
103:nitrogen
1242:Amylase
967:Lactate
962:content
888:Calcium
115:protein
84:12962-7
80:12963-5
76:12961-9
72:59570-2
55:D001806
1247:Lipase
873:Sodium
808:
738:
697:
687:
464:0.3571
131:kidney
127:assays
68:6299-2
1372:Other
220:Units
178:fever
119:blood
63:LOINC
903:Urea
806:ISBN
736:ISBN
713:link
695:OCLC
685:ISBN
638:Kt/V
614:2.14
100:urea
49:MeSH
41:Urea
1333:LFT
1207:GGT
1195:AST
1190:ALT
1178:ALP
1080:HDL
1075:LDL
172:),
137:or
113:of
96:BUN
1400::
958:CO
792:^
776:.
709:}}
705:{{
693:.
667:^
566:14
562:60
416:14
395:10
198:.
184:.
157:.
155:dL
82:,
78:,
74:,
70:,
960:2
848:e
841:t
834:v
814:.
786:.
744:.
715:)
701:.
606:L
603:d
599:/
595:g
592:m
588:N
584:U
581:B
578:=
572:2
552:L
549:d
545:/
541:g
538:m
534:N
530:U
527:B
524:=
519:L
516:d
512:/
508:g
505:m
501:a
497:e
494:r
491:U
456:L
453:d
449:/
445:g
442:m
438:N
434:U
431:B
428:=
422:2
410:L
406:/
402:L
399:d
384:L
381:d
377:/
373:g
370:m
366:N
362:U
359:B
356:=
351:L
347:/
343:l
340:o
337:m
334:m
330:N
326:U
323:B
320:=
315:L
311:/
307:l
304:o
301:m
298:m
294:a
290:e
287:r
284:U
259:L
256:d
252:/
248:g
245:m
241:N
237:U
234:B
151:L
94:(
23:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
