Hypoglycemia laboratory findings: Difference between revisions

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{{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]], [[24-hour|24-hour fasting]] and identifying the cause after that.
Laboratory investigations of hypoglycemia depend on many tests: [[plasma glucose]] is usually <55-70 mg/dL, [[Insulin|insulin,]] [[c-peptide]], [[proinsulin]], [[sulfonylurea]] screen, [[beta-hydroxybutyrate]], and 24-hour fasting [[Glucose levels low|glucose level]] are another tests that are required to establish the etiology.


==Laboratory Findings==
==Laboratory Findings==
===Defining Hypoglycemia===
===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.
The following three characteristics should be present to diagnose hypoglycemia, which is called [[Whipple's triad]] and include:<ref name="pmid17127144">{{cite journal| author=Guettier JM, Gorden P| title=Hypoglycemia. | journal=Endocrinol Metab Clin North Am | year= 2006 | volume= 35 | issue= 4 | pages= 753-66, viii-ix | pmid=17127144 | doi=10.1016/j.ecl.2006.09.005 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17127144  }}</ref>
 
So, Dependence on three characters to diagnose hypoglycemia is the accepted method. It is called [[Whipple's triad]] which includes:
* 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 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 [[Mixed mea|mixed meal.]]
* 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 is usually <55-70 mg/dL.
**[[Insulin]]
**[[Insulin]]
**[[C-peptide]]
**[[C-peptide]]
**[[Proinsulin]]
**[[Proinsulin]]
**[[Sulfonylurea]] and [[Meglitinide|meglitinide screen]]
**[[Sulfonylurea]] and [[Meglitinide|meglitinide screen]]
**[[Beta-hydroxybutyrate]]
**[[Beta-hydroxybutyrate]]<ref name="pmid15886243">{{cite journal| author=Service FJ, O'Brien PC| title=Increasing serum betahydroxybutyrate concentrations during the 72-hour fast: evidence against hyperinsulinemic hypoglycemia. | journal=J Clin Endocrinol Metab | year= 2005 | volume= 90 | issue= 8 | pages= 4555-8 | pmid=15886243 | doi=10.1210/jc.2005-0033 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15886243  }}</ref>
{| class="wikitable"
{| class="wikitable"
!Fasting evaluation<ref name="pmid19088155">{{cite journal| author=Cryer PE, Axelrod L, Grossman AB, Heller SR, Montori VM, Seaquist ER et al.| title=Evaluation and management of adult hypoglycemic disorders: an Endocrine Society Clinical Practice Guideline. | journal=J Clin Endocrinol Metab | year= 2009 | volume= 94 | issue= 3 | pages= 709-28 | pmid=19088155 | doi=10.1210/jc.2008-1410 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19088155  }}</ref>
!Fasting evaluation<ref name="pmid19088155">{{cite journal| author=Cryer PE, Axelrod L, Grossman AB, Heller SR, Montori VM, Seaquist ER et al.| title=Evaluation and management of adult hypoglycemic disorders: an Endocrine Society Clinical Practice Guideline. | journal=J Clin Endocrinol Metab | year= 2009 | volume= 94 | issue= 3 | pages= 709-28 | pmid=19088155 | doi=10.1210/jc.2008-1410 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=19088155 }}</ref><ref name="pmid11095416">{{cite journal| author=Service FJ, Natt N| title=The prolonged fast. | journal=J Clin Endocrinol Metab | year= 2000 | volume= 85 | issue= 11 | pages= 3973-4 | pmid=11095416 | doi=10.1210/jcem.85.11.6934 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11095416 }}</ref>
!Mixed-meal evaluation<ref name="pmid235895422">{{cite journal| author=Seaquist ER, Anderson J, Childs B, Cryer P, Dagogo-Jack S, Fish L et al.| title=Hypoglycemia and diabetes: a report of a workgroup of the American Diabetes Association and the Endocrine Society. | journal=Diabetes Care | year= 2013 | volume= 36 | issue= 5 | pages= 1384-95 | pmid=23589542 | doi=10.2337/dc12-2480 | pmc=3631867 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=23589542  }}</ref>
!Mixed-meal evaluation<ref name="pmid235895422">{{cite journal| author=Seaquist ER, Anderson J, Childs B, Cryer P, Dagogo-Jack S, Fish L et al.| title=Hypoglycemia and diabetes: a report of a workgroup of the American Diabetes Association and the Endocrine Society. | journal=Diabetes Care | year= 2013 | volume= 36 | issue= 5 | pages= 1384-95 | pmid=23589542 | doi=10.2337/dc12-2480 | pmc=3631867 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=23589542  }}</ref>
|-
|-
|
|
* If prolonged fasting may result in an episode of symptomatic hypoglycemia, plasma glucose should be measured repeatedly during fasting.
* If prolonged fasting results 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, 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 results are equivocal, patient needs another confirmatory test, such as 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, blood glucose must be measured.
* 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.
|}
|}


=== [[24-hour|24-hour fasting]] ===
=== [[24-hour|24-hour fasting]] ===
* Increased release of [[glucagon]], [[epinephrine]], and [[cortisol]] is the most important factors that keep [[Blood sugar|blood glucose]] concentrations from falling during fasting.  
* Increased release of [[glucagon]], [[epinephrine]], and [[cortisol]] are the most important factors that keep [[Blood sugar|blood glucose]] concentrations from falling during fasting.  
* [[Gluconeogenesis]] is the most important factor of [[glucose]] production after a prolonged fast.<ref name="pmid8755648">{{cite journal| author=Landau BR, Wahren J, Chandramouli V, Schumann WC, Ekberg K, Kalhan SC| title=Contributions of gluconeogenesis to glucose production in the fasted state. | journal=J Clin Invest | year= 1996 | volume= 98 | issue= 2 | pages= 378-85 | pmid=8755648 | doi=10.1172/JCI118803 | pmc=507441 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8755648  }}</ref>  
* [[Gluconeogenesis]] is the most important factor of [[glucose]] production after a prolonged fast.<ref name="pmid8755648">{{cite journal| author=Landau BR, Wahren J, Chandramouli V, Schumann WC, Ekberg K, Kalhan SC| title=Contributions of gluconeogenesis to glucose production in the fasted state. | journal=J Clin Invest | year= 1996 | volume= 98 | issue= 2 | pages= 378-85 | pmid=8755648 | doi=10.1172/JCI118803 | pmc=507441 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8755648  }}</ref>  
* If there is a high level of insulin, [[gluconeogenesis]] will be inhibited causing hypoglycemia during fasting.
* If insulin level is high, [[gluconeogenesis]] will be inhibited causing hypoglycemia during fasting.<ref name="pmid6876881">{{cite journal| author=Hogan MJ, Service FJ, Sharbrough FW, Gerich JE| title=Oral glucose tolerance test compared with a mixed meal in the diagnosis of reactive hypoglycemia. A caveat on stimulation. | journal=Mayo Clin Proc | year= 1983 | volume= 58 | issue= 8 | pages= 491-6 | pmid=6876881 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=6876881  }}</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>
* The fasting should be stopped in any of the following conditions: <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
**Presence or absence of effects
**The purpose of the definition


=== Identifying the cause ===
=== 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:
The following table describes the possible causes of hypoglycemia.
{| class="wikitable"
{| class="wikitable"
!
!
!Plasma insulin
!Plasma insulin<ref name="pmid17609405">{{cite journal| author=Vezzosi D, Bennet A, Fauvel J, Caron P| title=Insulin, C-peptide and proinsulin for the biochemical diagnosis of hypoglycaemia related to endogenous hyperinsulinism. | journal=Eur J Endocrinol | year= 2007 | volume= 157 | issue= 1 | pages= 75-83 | pmid=17609405 | doi=10.1530/EJE-07-0109 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17609405  }}</ref>
![[C-peptide]]
!C-peptide<ref name="pmid17609405" />
![[proinsulin]]
!proinsulin
![[Sulfonylurea]] in plasma
!Sulfonylurea in plasma
!insulin or [[Insulin antibodies|insulin receptor antibodies]]
!insulin or insulin receptor antibodies
![[Postprandial]] symptoms
!Postprandial symptoms
!Fating symptoms
!Fasting symptoms
|-
|-
|[[Insulinoma]]
|[[Insulinoma]]
|high
|High
|high
|High
|high
|High
| -
| -
| -
| -
Line 73: Line 69:
| +
| +
|-
|-
|[[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
| + <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>
| +
| -
| -
| -
| -
| -
| -
|-
|-
|[[Autoimmune hypoglycemia]]
|[[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
| -
| -
| + <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>
| +  
| -
| -
| -
| -
|-
|-
|[[NIPHS]]*
|[[NIPHS]]*
|high
|High
|high
|High
|high
|High
| -
| -
| -
| -
Line 101: Line 97:
|-
|-
|Exogenous [[insulin]]
|Exogenous [[insulin]]
|high
|High
|low
|Low
|low
|Low
| -
| -
| -
| -
Line 110: Line 106:
|-
|-
|[[Non-islet|Non-islet cell tumors]]
|[[Non-islet|Non-islet cell tumors]]
|low
|Low
|low
|Low
|low
|Low
| -
| -
| -
| -
Line 123: Line 119:
Most of the neonatal hypoglycemias are transient but suspected cases as following should be investigated for metabolic diseases:   
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
* 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 132: Line 128:
* [[Free fatty acids]], [[Acylcarnitine hydrolase|acylcarnitine profile]], plasma free and total [[Carnitine|carnitine levels]]  
* [[Free fatty acids]], [[Acylcarnitine hydrolase|acylcarnitine profile]], plasma free and total [[Carnitine|carnitine levels]]  


* [[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>
 
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==
==References==
{{Reflist|2}}
{{Reflist|2}}

Latest revision as of 14:37, 16 November 2017

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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 is usually <55-70 mg/dL, insulin, c-peptide, proinsulin, sulfonylurea screen, beta-hydroxybutyrate, and 24-hour fasting glucose level are another tests that are required to establish the etiology.

Laboratory Findings

Defining Hypoglycemia

The following three characteristics should be present to diagnose hypoglycemia, which is called Whipple's triad and include:[1]

The strategy is to seek Whipple's triad under conditions in which hypoglycemia would be expected:

Fasting evaluation[3][4] Mixed-meal evaluation[5]
  • If prolonged fasting results in an episode of symptomatic hypoglycemia, plasma glucose should be measured repeatedly during fasting.
  • If symptoms occur and hypoglycemia is documented, other tests mentioned above should be performed.
  • If results are equivocal, patient needs another confirmatory test, such as 72-hour fast.
  • If symptoms appear within 5 hours after meals, we should suspect postprandial hypoglycemia.[6]
  • Recurrent sampling before and after meals for the following 5 hours will help diagnosis; If severe symptoms occur, blood glucose must be measured.
  • If Whipple's triad is demonstrated, sulfonylureas, meglitinides, and antibodies to insulin should also be measured.

24-hour fasting

  • The fasting should be stopped in any of the following conditions: [9]
    • 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:[10][11]
    • Measurement method
    • Age

Identifying the cause

The following table describes the possible causes of hypoglycemia.

Plasma insulin[12] C-peptide[12] proinsulin Sulfonylurea in plasma insulin or insulin receptor antibodies Postprandial symptoms Fasting symptoms
Insulinoma High High High - - - +
Oral hypoglycemics[13] High High High + - - -
Autoimmune hypoglycemia[14] 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?

References

  1. ↑ Guettier JM, Gorden P (2006). "Hypoglycemia". Endocrinol Metab Clin North Am. 35 (4): 753–66, viii–ix. doi:10.1016/j.ecl.2006.09.005. PMID 17127144.
  2. ↑ Service FJ, O'Brien PC (2005). "Increasing serum betahydroxybutyrate concentrations during the 72-hour fast: evidence against hyperinsulinemic hypoglycemia". J Clin Endocrinol Metab. 90 (8): 4555–8. doi:10.1210/jc.2005-0033. PMID 15886243.
  3. ↑ 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.
  4. ↑ Service FJ, Natt N (2000). "The prolonged fast". J Clin Endocrinol Metab. 85 (11): 3973–4. doi:10.1210/jcem.85.11.6934. PMID 11095416.
  5. ↑ 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.
  6. ↑ Service FJ (1999). "Diagnostic approach to adults with hypoglycemic disorders". Endocrinol Metab Clin North Am. 28 (3): 519–32, vi. PMID 10500929.
  7. ↑ 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.
  8. ↑ Hogan MJ, Service FJ, Sharbrough FW, Gerich JE (1983). "Oral glucose tolerance test compared with a mixed meal in the diagnosis of reactive hypoglycemia. A caveat on stimulation". Mayo Clin Proc. 58 (8): 491–6. PMID 6876881.
  9. ↑ Service FJ (1999). "Diagnostic approach to adults with hypoglycemic disorders". Endocrinol Metab Clin North Am. 28 (3): 519–32, vi. PMID 10500929.
  10. ↑ 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.
  11. ↑ 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.
  12. ↑ 12.0 12.1 Vezzosi D, Bennet A, Fauvel J, Caron P (2007). "Insulin, C-peptide and proinsulin for the biochemical diagnosis of hypoglycaemia related to endogenous hyperinsulinism". Eur J Endocrinol. 157 (1): 75–83. doi:10.1530/EJE-07-0109. PMID 17609405.
  13. ↑ 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.
  14. ↑ 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.
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