1. INVESTIGATIONS AND DIFFERENTIALS OF HYPERGLYCAEMIC EMERGENCIES
ILERHUNMWUWA P.N (MBBS, Benin)
Senior Registrar
Endocrinology, Diabetes and Metabolism Unit

2. OUTLINE Investigations to confirm diagnosis and assess severity
Ancillary investigations
Investigations to establish precipitants
Differentials

3. INVESTIGATIONS TO CONFIRM DIAGNOSIS AND ASSESS SEVERITY
DKA(mild)
DKA( moderate)
DKA( severe)
HHS
Plasma glucose (mg/dl)
250
> 250
600
Urine ketones
++/+++ . May be negative.
+/Absent
Serum ketones *
++/+++
Serum osmolarity (mOsm/L)
Serum Osmolarity (in mOsm/L) = 2[Na++K] + plasma glucose + plasma urea
Normal Serum Osmolarity = mOsmol/L
Variable
> 320

4. ……contd DKA(mild) DKA(moderate) DKA(severe) HHS
Anion gap = (Na++K+) – (HCO3-+Cl-)
Normal anion gap = 10–12 mmol/L
> 10. Typically above 14
> 12. Typically above 14
> 12
Variable. Typically normal.
Serum bicarbonate (mEq/L)*
Normal value =
< 10
> 15
Arterial pH *
Normal arterial pH =
7.25 – 7.30
7.00 – 7.24
< 7.00
> 7.30
* Used to assess severity

5. ANCILIARY INVESTIGATIONS
Comments
Full blood count with differentials
Anemia, leukocytosis typical and does not indicate infection
Leukocyte counts commonly between to cells per uL
Leukocyte counts above suggests infection
Peripheral blood fiml important to establish infection
Electrolytes, urea and creatinine
Serum sodium typically low or near-normal in DKA but high in HHS
Serum potassium may be elevated, normal or low.
Azotemia may result from dehydration, or indicate renal failure as the precipitant.
Fasting lipid profile
Hypertriglyceridemia may account for pseudohypnatraemia and pseudonormoglycaemias
Serum lactate
Could be elevated in DKA
In the presence of normal plasma glucose, strongly suggests lactic acidosis.

6. INVESTIGATIONS TO ESTABLISH PRECIPITANTS
Urine m/c/s
Sputum m/c/s
Blood culture
Cardiac enzymes
ECG
Chest x-ray
Brain imaging
Thyroid function tests
Toxicology screening

7. DIFFERENTIAL DIAGNOSES
1. Other causes of acute abdomen e.g acute pancreatitis, peptic ulcer
disease
2. Other causes of altered sensorium e.g meningitis, cerebral malaria
3. Other causes of ketosis e.g starvation, alcohol ingestion
4. Other causes of high-anion gap metabolic acidosis e.g lactic
acidosis

8. SUMMARY
Investigations are needed to establish the type of hyperglycaemic
emergencies as this will ultimately influence the line of management.
It is very important to establish the precipitant as failure to do this
may result in poor response to treatment.
There are many conditions that can mimic the presentation of
hyperglycaemic emergencies and these must be sought for in the
history and consequently investigations.

9. REFERENCES Diabetes Care. 2009; 32(7): 1335- 1343.
Slovis CM, Mork VG, Slovis RJ, et al. Diabetic ketoacidosis and
infection: leukocyte count and differential as early predictors of
serious infection. Am J Emerg Med 1987; 5: 1-5.
Sheikh-Ali M, Karon BS, Basu A, et al. Can serum beta-
hydroxybutyrate be used to diagnose diabetic ketoacidosis? Diabetes
Care 2008; 31: