Hypoglycemia laboratory findings: Difference between revisions
No edit summary |
|||
Line 3: | Line 3: | ||
{{CMG}} {{AE}} {{MAD}} | {{CMG}} {{AE}} {{MAD}} | ||
==Overview== | ==Overview== | ||
Laboratory investigations of hypoglycemia depend on many tests: plasma glucose should be <55 mg/dL, [[Insulin|insulin,]] [[c-peptide]], [[proinsulin]], [[sulfonylurea]] screen, [[beta-hydroxybutyrate]], | Laboratory investigations of hypoglycemia depend on many tests: [[plasma glucose]] should be <55 mg/dL, [[Insulin|insulin,]] [[c-peptide]], [[proinsulin]], [[sulfonylurea]] screen, [[beta-hydroxybutyrate]], 24-hour fasting [[Glucose levels low|glucose level]] and identifying the cause after that. | ||
==Laboratory Findings== | ==Laboratory Findings== | ||
Line 12: | Line 12: | ||
* Symptoms of hypoglycemia | * Symptoms of hypoglycemia | ||
* A low [[plasma glucose]] concentration correlated with symptoms | * A low [[plasma glucose]] concentration correlated with symptoms | ||
* Correction of glucose level relieves symptoms | * Correction of [[Glucose levels low|glucose level]] relieves symptoms | ||
The strategy is to seek [[Whipple's triad]] under conditions in which hypoglycemia would be expected: | The strategy is to seek [[Whipple's triad]] under conditions in which hypoglycemia would be expected: | ||
* If the symptoms occur in the [[Fasting plasma glucose|fasting state]], that evaluation should be performed during fasting. | * If the symptoms occur in the [[Fasting plasma glucose|fasting state]], that evaluation should be performed during fasting. | ||
* If there is a compelling history of postprandial symptoms, it is reasonable to seek [[Whipple's triad]] with frequent, timed plasma [[Blood glucose monitoring|glucose measurements]] and recording of any symptoms after a | * If there is a compelling history of postprandial symptoms, it is reasonable to seek [[Whipple's triad]] with frequent, timed plasma [[Blood glucose monitoring|glucose measurements]] and recording of any symptoms after a mixed meal. | ||
* All of the following should be measured: | * All of the following should be measured: | ||
**[[Glucose]]: plasma glucose should be <55 mg/dL. | **[[Glucose]]: plasma glucose should be <55 mg/dL. | ||
Line 28: | Line 28: | ||
|- | |- | ||
| | | | ||
* If prolonged fasting may result in an episode of symptomatic hypoglycemia, plasma glucose should be measured repeatedly during fasting. | * If prolonged fasting may result in an episode of symptomatic hypoglycemia, [[plasma glucose]] should be measured repeatedly during fasting. | ||
* If symptoms occur and hypoglycemia is documented, the other tests mentioned above should be performed. | * If symptoms occur and hypoglycemia is documented, the other tests mentioned above should be performed. | ||
* If the results are equivocal so the patient needs another confirmatory test such as the [[72 hour|72-hour fast.]] | * If the results are equivocal so the patient needs another confirmatory test such as the [[72 hour|72-hour fast.]] | ||
| | | | ||
* If symptoms appear within 5 hours after meals, we should suspect postprandial hypoglycemia.<ref name="pmid105009292">{{cite journal| author=Service FJ| title=Diagnostic approach to adults with hypoglycemic disorders. | journal=Endocrinol Metab Clin North Am | year= 1999 | volume= 28 | issue= 3 | pages= 519-32, vi | pmid=10500929 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10500929 }}</ref> | * If symptoms appear within 5 hours after meals, we should suspect postprandial hypoglycemia.<ref name="pmid105009292">{{cite journal| author=Service FJ| title=Diagnostic approach to adults with hypoglycemic disorders. | journal=Endocrinol Metab Clin North Am | year= 1999 | volume= 28 | issue= 3 | pages= 519-32, vi | pmid=10500929 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10500929 }}</ref> | ||
* Recurrent sampling before and after meals for the following 5 hours will help diagnosis; If severe symptoms occur, the samples for glucose should be analyzed. | * Recurrent sampling before and after meals for the following 5 hours will help diagnosis; If severe symptoms occur, the samples for [[glucose]] should be analyzed. | ||
* If Whipple's triad is demonstrated, [[sulfonylureas]], [[Meglitinide|meglitinides]], and antibodies to insulin should also be measured. | * If [[Whipple's triad]] is demonstrated, [[sulfonylureas]], [[Meglitinide|meglitinides]], and antibodies to insulin should also be measured. | ||
|} | |} | ||
Line 44: | Line 44: | ||
* The fasting is ended when: <ref name="pmid10500929">{{cite journal| author=Service FJ| title=Diagnostic approach to adults with hypoglycemic disorders. | journal=Endocrinol Metab Clin North Am | year= 1999 | volume= 28 | issue= 3 | pages= 519-32, vi | pmid=10500929 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10500929 }}</ref> | * The fasting is ended when: <ref name="pmid10500929">{{cite journal| author=Service FJ| title=Diagnostic approach to adults with hypoglycemic disorders. | journal=Endocrinol Metab Clin North Am | year= 1999 | volume= 28 | issue= 3 | pages= 519-32, vi | pmid=10500929 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10500929 }}</ref> | ||
**Seventy-two hours have passed | **Seventy-two hours have passed | ||
**Plasma glucose concentration is ≤45 mg/dL | **[[Plasma glucose]] concentration is ≤45 mg/dL | ||
**Patient has symptoms or signs of hypoglycemia | **Patient has symptoms or signs of hypoglycemia | ||
* The precise level of glucose considered low enough to define hypoglycemia is dependent on:<ref name="Cornblath_1990">{{cite journal |author=Cornblath M, Schwartz R, Aynsley-Green A, Lloyd JK |title=Hypoglycemia in infancy: the need for a rational definition. A Ciba Foundation discussion meeting |journal=Pediatrics |volume=85 |issue=5 |pages=834-7 |year=1990 |pmid=2330247}}</ref><ref name="Cornblath_2000">{{cite journal |author=Cornblath M, Hawdon JM, Williams AF, Aynsley-Green A, Ward-Platt MP, Schwartz R, Kalhan SC |title=Controversies regarding definition of neonatal hypoglycemia: suggested operational thresholds |journal=Pediatrics |volume=105 |issue=5 |pages=1141-5 |year=2000 |pmid=10790476}}</ref> | * The precise level of [[glucose]] considered low enough to define hypoglycemia is dependent on:<ref name="Cornblath_1990">{{cite journal |author=Cornblath M, Schwartz R, Aynsley-Green A, Lloyd JK |title=Hypoglycemia in infancy: the need for a rational definition. A Ciba Foundation discussion meeting |journal=Pediatrics |volume=85 |issue=5 |pages=834-7 |year=1990 |pmid=2330247}}</ref><ref name="Cornblath_2000">{{cite journal |author=Cornblath M, Hawdon JM, Williams AF, Aynsley-Green A, Ward-Platt MP, Schwartz R, Kalhan SC |title=Controversies regarding definition of neonatal hypoglycemia: suggested operational thresholds |journal=Pediatrics |volume=105 |issue=5 |pages=1141-5 |year=2000 |pmid=10790476}}</ref> | ||
**Measurement method | **Measurement method | ||
**Age of the person | **Age of the person | ||
Line 60: | Line 60: | ||
![[proinsulin]] | ![[proinsulin]] | ||
![[Sulfonylurea]] in plasma | ![[Sulfonylurea]] in plasma | ||
!insulin or [[Insulin | ![[insulin]] or [[Insulin receptor|insulin receptor antibodies]] | ||
![[Postprandial]] symptoms | ![[Postprandial]] symptoms | ||
!Fating symptoms | !Fating symptoms | ||
Line 73: | Line 73: | ||
| + | | + | ||
|- | |- | ||
|[[Oral hypoglycemics]] | |[[Oral hypoglycemics]]<ref name="pmid9056803">{{cite journal| author=Perros P, Henderson AK, Carter DC, Toft AD| title=Lesson of the week. Are spontaneous hypoglycaemia, raised plasma insulin and C peptide concentrations, and abnormal pancreatic images enough to diagnose insulinoma? | journal=BMJ | year= 1997 | volume= 314 | issue= 7079 | pages= 496-7 | pmid=9056803 | doi= | pmc=2125998 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=9056803 }}</ref> | ||
|high | |high | ||
|high | |high | ||
|high | |high | ||
| + | | + | ||
| - | | - | ||
| - | | - | ||
| - | | - | ||
|- | |- | ||
|[[Autoimmune | |[[Autoimmune]] hypoglycemia<ref name="pmid19440117">{{cite journal| author=Lupsa BC, Chong AY, Cochran EK, Soos MA, Semple RK, Gorden P| title=Autoimmune forms of hypoglycemia. | journal=Medicine (Baltimore) | year= 2009 | volume= 88 | issue= 3 | pages= 141-53 | pmid=19440117 | doi=10.1097/MD.0b013e3181a5b42e | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19440117 }}</ref> | ||
|high | |high | ||
|high | |high | ||
|high | |high | ||
| - | | - | ||
| + | | + | ||
| - | | - | ||
| - | | - | ||
Line 124: | Line 124: | ||
* Hypoglycemia that requires prolonged high rates of [[dextrose]] infusion | * Hypoglycemia that requires prolonged high rates of [[dextrose]] infusion | ||
* [[Persistent hypoglycemia]] | * [[Persistent hypoglycemia]] | ||
* Neurologic symptoms | * [[Neurological|Neurologic]] symptoms | ||
* History or physical findings suggestive of metabolic disease | * History or physical findings suggestive of metabolic disease | ||
Line 134: | Line 134: | ||
* [[Growth hormone]] and [[Cortisol]]. | * [[Growth hormone]] and [[Cortisol]]. | ||
* [[Urine organic acids]] and [[Amino acids|serum amino acids.]] | * [[Urine organic acids]] and [[Amino acids|serum amino acids.]] | ||
Surveys of healthy children and adults show that plasma glucose below 60 mg/dL or above 100 mg/dL are found in less than 5% of samples after an overnight fast.<ref name="Meites">{{cite book |author=Samuel Meites, editor-in-chief; contributing editors, Gregory J. Buffone... [et al.] |title=Pediatric clinical chemistry: reference (normal) values |publisher=AACC Press |location=Washington, D.C |year=1989 |pages= |isbn=0-915274-47-7 |oclc= |doi=}}</ref> | Surveys of healthy children and adults show that [[plasma glucose]] below 60 mg/dL or above 100 mg/dL are found in less than 5% of samples after an overnight fast.<ref name="Meites">{{cite book |author=Samuel Meites, editor-in-chief; contributing editors, Gregory J. Buffone... [et al.] |title=Pediatric clinical chemistry: reference (normal) values |publisher=AACC Press |location=Washington, D.C |year=1989 |pages= |isbn=0-915274-47-7 |oclc= |doi=}}</ref> | ||
In infants and young children, up to 10% have been found to be below 60 mg/dL after an overnight fast. As the duration of fasting is extended, plasma glucose levels can fall further, even in healthy people. | In infants and young children, up to 10% have been found to be below 60 mg/dL after an overnight fast. As the duration of fasting is extended, [[plasma glucose]] levels can fall further, even in healthy people. | ||
In other words, many healthy people can occasionally have glucose levels in the hypoglycemic range without symptoms or disease. | In other words, many healthy people can occasionally have [[Glucose|glucose levels]] in the hypoglycemic range without symptoms or disease. | ||
==References== | ==References== | ||
{{Reflist|2}} | {{Reflist|2}} |
Revision as of 22:06, 19 September 2017
Hypoglycemia Microchapters |
Diagnosis |
---|
Treatment |
Case Studies |
Hypoglycemia laboratory findings On the Web |
American Roentgen Ray Society Images of Hypoglycemia laboratory findings |
Risk calculators and risk factors for Hypoglycemia laboratory findings |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Mohammed Abdelwahed M.D[2]
Overview
Laboratory investigations of hypoglycemia depend on many tests: plasma glucose should be <55 mg/dL, insulin, c-peptide, proinsulin, sulfonylurea screen, beta-hydroxybutyrate, 24-hour fasting glucose level and identifying the cause after that.
Laboratory Findings
Defining Hypoglycemia
Hypoglycemia can't be diagnosed only by measuring blood glucose level because it is misleading maneuver with high false positive results. The measurement should be repeated using a collection tube that contains an inhibitor of glycolysis and processing should not be delayed.
So, for hypoglycemia diagnosis to be made, the following 3 characteristics should be present, which is called Whipple's triad and includes:
- Symptoms of hypoglycemia
- A low plasma glucose concentration correlated with symptoms
- Correction of glucose level relieves symptoms
The strategy is to seek Whipple's triad under conditions in which hypoglycemia would be expected:
- If the symptoms occur in the fasting state, that evaluation should be performed during fasting.
- If there is a compelling history of postprandial symptoms, it is reasonable to seek Whipple's triad with frequent, timed plasma glucose measurements and recording of any symptoms after a mixed meal.
- All of the following should be measured:
- Glucose: plasma glucose should be <55 mg/dL.
- Insulin
- C-peptide
- Proinsulin
- Sulfonylurea and meglitinide screen
- Beta-hydroxybutyrate
Fasting evaluation[1] | Mixed-meal evaluation[2] |
---|---|
|
|
24-hour fasting
- Increased release of glucagon, epinephrine, and cortisol is the most important factors that keep blood glucose concentrations from falling during fasting.
- Gluconeogenesis is the most important factor of glucose production after a prolonged fast.[4]
- If there is a high level of insulin, gluconeogenesis will be inhibited causing hypoglycemia during fasting.
- The fasting is ended when: [5]
- Seventy-two hours have passed
- Plasma glucose concentration is ≤45 mg/dL
- Patient has symptoms or signs of hypoglycemia
- The precise level of glucose considered low enough to define hypoglycemia is dependent on:[6][7]
- Measurement method
- Age of the person
- Presence or absence of effects
- The purpose of the definition
Identifying the cause
After confirmation of hypoglycemia. Physicians should have history, signs and laboratory results sufficient to help them to identify the cause of hypoglycemia:
Plasma insulin | C-peptide | proinsulin | Sulfonylurea in plasma | insulin or insulin receptor antibodies | Postprandial symptoms | Fating symptoms | |
---|---|---|---|---|---|---|---|
Insulinoma | high | high | high | - | - | - | + |
Oral hypoglycemics[8] | high | high | high | + | - | - | - |
Autoimmune hypoglycemia[9] | high | high | high | - | + | - | - |
NIPHS* | high | high | high | - | - | + | - |
Exogenous insulin | high | low | low | - | - | - | - |
Non-islet cell tumors | low | low | low | - | - | - | - |
*(NIPHS) non-insulinoma pancreatogenous hypoglycemia syndrome
Neonatal hypoglycemia:
Most of the neonatal hypoglycemias are transient but suspected cases as following should be investigated for metabolic diseases:
- Hypoglycemia that requires prolonged high rates of dextrose infusion
- Persistent hypoglycemia
- Neurologic symptoms
- History or physical findings suggestive of metabolic disease
What to measure?
- Measure plasma insulin, plasma C-peptide and beta-hydroxybutyrate
- Blood pH, bicarbonate, and lactate
- Free fatty acids, acylcarnitine profile, plasma free and total carnitine levels
Surveys of healthy children and adults show that plasma glucose below 60 mg/dL or above 100 mg/dL are found in less than 5% of samples after an overnight fast.[10]
In infants and young children, up to 10% have been found to be below 60 mg/dL after an overnight fast. As the duration of fasting is extended, plasma glucose levels can fall further, even in healthy people.
In other words, many healthy people can occasionally have glucose levels in the hypoglycemic range without symptoms or disease.
References
- ↑ Cryer PE, Axelrod L, Grossman AB, Heller SR, Montori VM, Seaquist ER; et al. (2009). "Evaluation and management of adult hypoglycemic disorders: an Endocrine Society Clinical Practice Guideline". J Clin Endocrinol Metab. 94 (3): 709–28. doi:10.1210/jc.2008-1410. PMID 19088155.
- ↑ Seaquist ER, Anderson J, Childs B, Cryer P, Dagogo-Jack S, Fish L; et al. (2013). "Hypoglycemia and diabetes: a report of a workgroup of the American Diabetes Association and the Endocrine Society". Diabetes Care. 36 (5): 1384–95. doi:10.2337/dc12-2480. PMC 3631867. PMID 23589542.
- ↑ Service FJ (1999). "Diagnostic approach to adults with hypoglycemic disorders". Endocrinol Metab Clin North Am. 28 (3): 519–32, vi. PMID 10500929.
- ↑ Landau BR, Wahren J, Chandramouli V, Schumann WC, Ekberg K, Kalhan SC (1996). "Contributions of gluconeogenesis to glucose production in the fasted state". J Clin Invest. 98 (2): 378–85. doi:10.1172/JCI118803. PMC 507441. PMID 8755648.
- ↑ Service FJ (1999). "Diagnostic approach to adults with hypoglycemic disorders". Endocrinol Metab Clin North Am. 28 (3): 519–32, vi. PMID 10500929.
- ↑ Cornblath M, Schwartz R, Aynsley-Green A, Lloyd JK (1990). "Hypoglycemia in infancy: the need for a rational definition. A Ciba Foundation discussion meeting". Pediatrics. 85 (5): 834–7. PMID 2330247.
- ↑ Cornblath M, Hawdon JM, Williams AF, Aynsley-Green A, Ward-Platt MP, Schwartz R, Kalhan SC (2000). "Controversies regarding definition of neonatal hypoglycemia: suggested operational thresholds". Pediatrics. 105 (5): 1141–5. PMID 10790476.
- ↑ Perros P, Henderson AK, Carter DC, Toft AD (1997). "Lesson of the week. Are spontaneous hypoglycaemia, raised plasma insulin and C peptide concentrations, and abnormal pancreatic images enough to diagnose insulinoma?". BMJ. 314 (7079): 496–7. PMC 2125998. PMID 9056803.
- ↑ Lupsa BC, Chong AY, Cochran EK, Soos MA, Semple RK, Gorden P (2009). "Autoimmune forms of hypoglycemia". Medicine (Baltimore). 88 (3): 141–53. doi:10.1097/MD.0b013e3181a5b42e. PMID 19440117.
- ↑ Samuel Meites, editor-in-chief; contributing editors, Gregory J. Buffone... [et al.] (1989). Pediatric clinical chemistry: reference (normal) values. Washington, D.C: AACC Press. ISBN 0-915274-47-7.